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NAME
gl - Standard OpenGL api.
DESCRIPTION
Standard OpenGL api. See www.opengl.org
Booleans are represented by integers 0 and 1.
DATA TYPES
clamp() = float():
0.0..1.0
enum() = non_neg_integer():
See wx/include/gl.hrl
matrix() = {float(), float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float(), float(), float(), float()}:
mem() = binary() | tuple():
Memory block
offset() = non_neg_integer():
Offset in memory block
EXPORTS
clearIndex(C) -> ok
Types:
C = float()
Specify the clear value for the color index buffers
gl:clearIndex specifies the index used by gl:clear/1 to clear the color index
buffers. C is not clamped. Rather, C is converted to a fixed-point value with
unspecified precision to the right of the binary point. The integer part of this
value is then masked with 2 m-1, where m is the number of bits in a color index
stored in the frame buffer.
See external documentation.
clearColor(Red, Green, Blue, Alpha) -> ok
Types:
Red = clamp()
Green = clamp()
Blue = clamp()
Alpha = clamp()
Specify clear values for the color buffers
gl:clearColor specifies the red, green, blue, and alpha values used by gl:clear/1
to clear the color buffers. Values specified by gl:clearColor are clamped to the
range [0 1].
See external documentation.
clear(Mask) -> ok
Types:
Mask = integer()
Clear buffers to preset values
gl:clear sets the bitplane area of the window to values previously selected by
gl:clearColor , gl:clearDepth, and gl:clearStencil. Multiple color buffers can be
cleared simultaneously by selecting more than one buffer at a time using
gl:drawBuffer/1 .
The pixel ownership test, the scissor test, dithering, and the buffer writemasks
affect the operation of gl:clear. The scissor box bounds the cleared region. Alpha
function, blend function, logical operation, stenciling, texture mapping, and
depth-buffering are ignored by gl:clear.
gl:clear takes a single argument that is the bitwise OR of several values
indicating which buffer is to be cleared.
The values are as follows:
?GL_COLOR_BUFFER_BIT: Indicates the buffers currently enabled for color writing.
?GL_DEPTH_BUFFER_BIT: Indicates the depth buffer.
?GL_STENCIL_BUFFER_BIT: Indicates the stencil buffer.
The value to which each buffer is cleared depends on the setting of the clear value
for that buffer.
See external documentation.
indexMask(Mask) -> ok
Types:
Mask = integer()
Control the writing of individual bits in the color index buffers
gl:indexMask controls the writing of individual bits in the color index buffers.
The least significant n bits of Mask , where n is the number of bits in a color
index buffer, specify a mask. Where a 1 (one) appears in the mask, it's possible to
write to the corresponding bit in the color index buffer (or buffers). Where a 0
(zero) appears, the corresponding bit is write-protected.
This mask is used only in color index mode, and it affects only the buffers
currently selected for writing (see gl:drawBuffer/1 ). Initially, all bits are
enabled for writing.
See external documentation.
colorMask(Red, Green, Blue, Alpha) -> ok
Types:
Red = 0 | 1
Green = 0 | 1
Blue = 0 | 1
Alpha = 0 | 1
Enable and disable writing of frame buffer color components
gl:colorMask and gl:colorMaski specify whether the individual color components in
the frame buffer can or cannot be written. gl:colorMaski sets the mask for a
specific draw buffer, whereas gl:colorMask sets the mask for all draw buffers. If
Red is ?GL_FALSE, for example, no change is made to the red component of any pixel
in any of the color buffers, regardless of the drawing operation attempted.
Changes to individual bits of components cannot be controlled. Rather, changes are
either enabled or disabled for entire color components.
See external documentation.
alphaFunc(Func, Ref) -> ok
Types:
Func = enum()
Ref = clamp()
Specify the alpha test function
The alpha test discards fragments depending on the outcome of a comparison between
an incoming fragment's alpha value and a constant reference value. gl:alphaFunc
specifies the reference value and the comparison function. The comparison is
performed only if alpha testing is enabled. By default, it is not enabled. (See
gl:enable/1 and gl:enable/1 of ?GL_ALPHA_TEST.)
Func and Ref specify the conditions under which the pixel is drawn. The incoming
alpha value is compared to Ref using the function specified by Func . If the value
passes the comparison, the incoming fragment is drawn if it also passes subsequent
stencil and depth buffer tests. If the value fails the comparison, no change is
made to the frame buffer at that pixel location. The comparison functions are as
follows:
?GL_NEVER: Never passes.
?GL_LESS: Passes if the incoming alpha value is less than the reference value.
?GL_EQUAL: Passes if the incoming alpha value is equal to the reference value.
?GL_LEQUAL: Passes if the incoming alpha value is less than or equal to the
reference value.
?GL_GREATER: Passes if the incoming alpha value is greater than the reference
value.
?GL_NOTEQUAL: Passes if the incoming alpha value is not equal to the reference
value.
?GL_GEQUAL: Passes if the incoming alpha value is greater than or equal to the
reference value.
?GL_ALWAYS: Always passes (initial value).
gl:alphaFunc operates on all pixel write operations, including those resulting from
the scan conversion of points, lines, polygons, and bitmaps, and from pixel draw
and copy operations. gl:alphaFunc does not affect screen clear operations.
See external documentation.
blendFunc(Sfactor, Dfactor) -> ok
Types:
Sfactor = enum()
Dfactor = enum()
Specify pixel arithmetic
Pixels can be drawn using a function that blends the incoming (source) RGBA values
with the RGBA values that are already in the frame buffer (the destination values).
Blending is initially disabled. Use gl:enable/1 and gl:enable/1 with argument
?GL_BLEND to enable and disable blending.
gl:blendFunc defines the operation of blending for all draw buffers when it is
enabled. gl:blendFunci defines the operation of blending for a single draw buffer
specified by Buf when enabled for that draw buffer. Sfactor specifies which method
is used to scale the source color components. Dfactor specifies which method is
used to scale the destination color components. Both parameters must be one of the
following symbolic constants: ?GL_ZERO, ?GL_ONE, ?GL_SRC_COLOR,
?GL_ONE_MINUS_SRC_COLOR , ?GL_DST_COLOR, ?GL_ONE_MINUS_DST_COLOR, ?GL_SRC_ALPHA,
?GL_ONE_MINUS_SRC_ALPHA , ?GL_DST_ALPHA, ?GL_ONE_MINUS_DST_ALPHA,
?GL_CONSTANT_COLOR, ?GL_ONE_MINUS_CONSTANT_COLOR , ?GL_CONSTANT_ALPHA,
?GL_ONE_MINUS_CONSTANT_ALPHA, ?GL_SRC_ALPHA_SATURATE , ?GL_SRC1_COLOR,
?GL_ONE_MINUS_SRC1_COLOR, ?GL_SRC1_ALPHA, and ?GL_ONE_MINUS_SRC1_ALPHA . The
possible methods are described in the following table. Each method defines four
scale factors, one each for red, green, blue, and alpha. In the table and in
subsequent equations, first source, second source and destination color components
are referred to as (R s0 G s0 B s0 A s0), (R s1 G s1 B s1 A s1) and (R d G d B d A
d), respectively. The color specified by gl:blendColor/4 is referred to as (R c G c
B c A c). They are understood to have integer values between 0 and (k R k G k B k
A), where
k c=2(m c)-1
and (m R m G m B m A) is the number of red, green, blue, and alpha bitplanes.
Source and destination scale factors are referred to as (s R s G s B s A) and (d R
d G d B d A). The scale factors described in the table, denoted (f R f G f B f A),
represent either source or destination factors. All scale factors have range [0
1].Parameter(f R f G f B f A)
?GL_ZERO (0 0 0 0)
?GL_ONE(1 1 1 1)
?GL_SRC_COLOR (R s0 k/R G s0 k/G B s0 k/B A s0 k/A)
?GL_ONE_MINUS_SRC_COLOR(1 1 1 1)-(R s0 k/R G s0 k/G B s0 k/B A s0 k/A)
?GL_DST_COLOR (R d k/R G d k/G B d k/B A d k/A)
?GL_ONE_MINUS_DST_COLOR(1 1 1 1)-(R d k/R G d k/G B d k/B A d k/A)
?GL_SRC_ALPHA (A s0 k/A A s0 k/A A s0 k/A A s0 k/A)
?GL_ONE_MINUS_SRC_ALPHA(1 1 1 1)-(A s0 k/A A s0 k/A A s0 k/A A s0 k/A)
?GL_DST_ALPHA (A d k/A A d k/A A d k/A A d k/A)
?GL_ONE_MINUS_DST_ALPHA(1 1 1 1)-(A d k/A A d k/A A d k/A A d k/A)
?GL_CONSTANT_COLOR (R c G c B c A c)
?GL_ONE_MINUS_CONSTANT_COLOR(1 1 1 1)-(R c G c B c A c)
?GL_CONSTANT_ALPHA(A c A c A c A c)
?GL_ONE_MINUS_CONSTANT_ALPHA (1 1 1 1)-(A c A c A c A c)
?GL_SRC_ALPHA_SATURATE(i i i 1)
?GL_SRC1_COLOR (R s1 k/R G s1 k/G B s1 k/B A s1 k/A)
?GL_ONE_MINUS_SRC1_COLOR(1 1 1 1)-(R s1 k/R G s1 k/G B s1 k/B A s1 k/A)
?GL_SRC1_ALPHA (A s1 k/A A s1 k/A A s1 k/A A s1 k/A)
?GL_ONE_MINUS_SRC1_ALPHA(1 1 1 1)-(A s1 k/A A s1 k/A A s1 k/A A s1 k/A)
In the table,
i=min(A s k A-A d) k/A
To determine the blended RGBA values of a pixel, the system uses the following
equations:
R d=min(k R R s s R+R d d R) G d=min(k G G s s G+G d d G) B d=min(k B B s s B+B d d
B) A d=min(k A A s s A+A d d A)
Despite the apparent precision of the above equations, blending arithmetic is not
exactly specified, because blending operates with imprecise integer color values.
However, a blend factor that should be equal to 1 is guaranteed not to modify its
multiplicand, and a blend factor equal to 0 reduces its multiplicand to 0. For
example, when Sfactor is ?GL_SRC_ALPHA , Dfactor is ?GL_ONE_MINUS_SRC_ALPHA, and A
s is equal to k A, the equations reduce to simple replacement:
R d=R s G d=G s B d=B s A d=A s
See external documentation.
logicOp(Opcode) -> ok
Types:
Opcode = enum()
Specify a logical pixel operation for rendering
gl:logicOp specifies a logical operation that, when enabled, is applied between the
incoming RGBA color and the RGBA color at the corresponding location in the frame
buffer. To enable or disable the logical operation, call gl:enable/1 and
gl:enable/1 using the symbolic constant ?GL_COLOR_LOGIC_OP. The initial value is
disabled.OpcodeResulting Operation
?GL_CLEAR 0
?GL_SET 1
?GL_COPY s
?GL_COPY_INVERTED ~s
?GL_NOOP d
?GL_INVERT ~d
?GL_AND s & d
?GL_NAND ~(s & d)
?GL_OR s | d
?GL_NOR ~(s | d)
?GL_XOR s ^ d
?GL_EQUIV ~(s ^ d)
?GL_AND_REVERSE s & ~d
?GL_AND_INVERTED ~s & d
?GL_OR_REVERSE s | ~d
?GL_OR_INVERTED ~s | d
Opcode is a symbolic constant chosen from the list above. In the explanation of the
logical operations, s represents the incoming color and d represents the color in
the frame buffer. Standard C-language operators are used. As these bitwise
operators suggest, the logical operation is applied independently to each bit pair
of the source and destination colors.
See external documentation.
cullFace(Mode) -> ok
Types:
Mode = enum()
Specify whether front- or back-facing facets can be culled
gl:cullFace specifies whether front- or back-facing facets are culled (as specified
by mode) when facet culling is enabled. Facet culling is initially disabled. To
enable and disable facet culling, call the gl:enable/1 and gl:enable/1 commands
with the argument ?GL_CULL_FACE. Facets include triangles, quadrilaterals,
polygons, and rectangles.
gl:frontFace/1 specifies which of the clockwise and counterclockwise facets are
front-facing and back-facing. See gl:frontFace/1 .
See external documentation.
frontFace(Mode) -> ok
Types:
Mode = enum()
Define front- and back-facing polygons
In a scene composed entirely of opaque closed surfaces, back-facing polygons are
never visible. Eliminating these invisible polygons has the obvious benefit of
speeding up the rendering of the image. To enable and disable elimination of back-
facing polygons, call gl:enable/1 and gl:enable/1 with argument ?GL_CULL_FACE.
The projection of a polygon to window coordinates is said to have clockwise winding
if an imaginary object following the path from its first vertex, its second vertex,
and so on, to its last vertex, and finally back to its first vertex, moves in a
clockwise direction about the interior of the polygon. The polygon's winding is
said to be counterclockwise if the imaginary object following the same path moves
in a counterclockwise direction about the interior of the polygon. gl:frontFace
specifies whether polygons with clockwise winding in window coordinates, or
counterclockwise winding in window coordinates, are taken to be front-facing.
Passing ?GL_CCW to Mode selects counterclockwise polygons as front-facing; ?GL_CW
selects clockwise polygons as front-facing. By default, counterclockwise polygons
are taken to be front-facing.
See external documentation.
pointSize(Size) -> ok
Types:
Size = float()
Specify the diameter of rasterized points
gl:pointSize specifies the rasterized diameter of points. If point size mode is
disabled (see gl:enable/1 with parameter ?GL_PROGRAM_POINT_SIZE), this value will
be used to rasterize points. Otherwise, the value written to the shading language
built-in variable gl_PointSize will be used.
See external documentation.
lineWidth(Width) -> ok
Types:
Width = float()
Specify the width of rasterized lines
gl:lineWidth specifies the rasterized width of both aliased and antialiased lines.
Using a line width other than 1 has different effects, depending on whether line
antialiasing is enabled. To enable and disable line antialiasing, call gl:enable/1
and gl:enable/1 with argument ?GL_LINE_SMOOTH. Line antialiasing is initially
disabled.
If line antialiasing is disabled, the actual width is determined by rounding the
supplied width to the nearest integer. (If the rounding results in the value 0, it
is as if the line width were 1.) If |Δ x|>=|Δ y|, i pixels are filled
in each column that is rasterized, where i is the rounded value of Width .
Otherwise, i pixels are filled in each row that is rasterized.
If antialiasing is enabled, line rasterization produces a fragment for each pixel
square that intersects the region lying within the rectangle having width equal to
the current line width, length equal to the actual length of the line, and centered
on the mathematical line segment. The coverage value for each fragment is the
window coordinate area of the intersection of the rectangular region with the
corresponding pixel square. This value is saved and used in the final rasterization
step.
Not all widths can be supported when line antialiasing is enabled. If an
unsupported width is requested, the nearest supported width is used. Only width 1
is guaranteed to be supported; others depend on the implementation. Likewise, there
is a range for aliased line widths as well. To query the range of supported widths
and the size difference between supported widths within the range, call
gl:getBooleanv/1 with arguments ?GL_ALIASED_LINE_WIDTH_RANGE ,
?GL_SMOOTH_LINE_WIDTH_RANGE, and ?GL_SMOOTH_LINE_WIDTH_GRANULARITY.
See external documentation.
lineStipple(Factor, Pattern) -> ok
Types:
Factor = integer()
Pattern = integer()
Specify the line stipple pattern
Line stippling masks out certain fragments produced by rasterization; those
fragments will not be drawn. The masking is achieved by using three parameters: the
16-bit line stipple pattern Pattern , the repeat count Factor , and an integer
stipple counter s.
Counter s is reset to 0 whenever gl:'begin'/1 is called and before each line
segment of a gl:'begin'/1 (?GL_LINES)/ gl:'begin'/1 sequence is generated. It is
incremented after each fragment of a unit width aliased line segment is generated
or after each i fragments of an i width line segment are generated. The i fragments
associated with count s are masked out if
Pattern bit (s/factor)% 16
is 0, otherwise these fragments are sent to the frame buffer. Bit zero of Pattern
is the least significant bit.
Antialiased lines are treated as a sequence of 1×width rectangles for purposes of
stippling. Whether rectangle s is rasterized or not depends on the fragment rule
described for aliased lines, counting rectangles rather than groups of fragments.
To enable and disable line stippling, call gl:enable/1 and gl:enable/1 with
argument ?GL_LINE_STIPPLE. When enabled, the line stipple pattern is applied as
described above. When disabled, it is as if the pattern were all 1's. Initially,
line stippling is disabled.
See external documentation.
polygonMode(Face, Mode) -> ok
Types:
Face = enum()
Mode = enum()
Select a polygon rasterization mode
gl:polygonMode controls the interpretation of polygons for rasterization. Face
describes which polygons Mode applies to: both front and back-facing polygons
(?GL_FRONT_AND_BACK ). The polygon mode affects only the final rasterization of
polygons. In particular, a polygon's vertices are lit and the polygon is clipped
and possibly culled before these modes are applied.
Three modes are defined and can be specified in Mode :
?GL_POINT: Polygon vertices that are marked as the start of a boundary edge are
drawn as points. Point attributes such as ?GL_POINT_SIZE and ?GL_POINT_SMOOTH
control the rasterization of the points. Polygon rasterization attributes other
than ?GL_POLYGON_MODE have no effect.
?GL_LINE: Boundary edges of the polygon are drawn as line segments. Line attributes
such as ?GL_LINE_WIDTH and ?GL_LINE_SMOOTH control the rasterization of the lines.
Polygon rasterization attributes other than ?GL_POLYGON_MODE have no effect.
?GL_FILL: The interior of the polygon is filled. Polygon attributes such as
?GL_POLYGON_SMOOTH control the rasterization of the polygon.
See external documentation.
polygonOffset(Factor, Units) -> ok
Types:
Factor = float()
Units = float()
Set the scale and units used to calculate depth values
When ?GL_POLYGON_OFFSET_FILL, ?GL_POLYGON_OFFSET_LINE, or ?GL_POLYGON_OFFSET_POINT
is enabled, each fragment's depth value will be offset after it is interpolated
from the depth values of the appropriate vertices. The value of the offset is
factor×DZ+r×units, where DZ is a measurement of the change in depth relative to the
screen area of the polygon, and r is the smallest value that is guaranteed to
produce a resolvable offset for a given implementation. The offset is added before
the depth test is performed and before the value is written into the depth buffer.
gl:polygonOffset is useful for rendering hidden-line images, for applying decals to
surfaces, and for rendering solids with highlighted edges.
See external documentation.
polygonStipple(Mask) -> ok
Types:
Mask = binary()
Set the polygon stippling pattern
Polygon stippling, like line stippling (see gl:lineStipple/2 ), masks out certain
fragments produced by rasterization, creating a pattern. Stippling is independent
of polygon antialiasing.
Pattern is a pointer to a 32×32 stipple pattern that is stored in memory just like
the pixel data supplied to a gl:drawPixels/5 call with height and width both equal
to 32, a pixel format of ?GL_COLOR_INDEX, and data type of ?GL_BITMAP . That is,
the stipple pattern is represented as a 32×32 array of 1-bit color indices packed
in unsigned bytes. gl:pixelStoref/2 parameters like ?GL_UNPACK_SWAP_BYTES and
?GL_UNPACK_LSB_FIRST affect the assembling of the bits into a stipple pattern.
Pixel transfer operations (shift, offset, pixel map) are not applied to the stipple
image, however.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a stipple pattern is specified, Pattern is treated as
a byte offset into the buffer object's data store.
To enable and disable polygon stippling, call gl:enable/1 and gl:enable/1 with
argument ?GL_POLYGON_STIPPLE. Polygon stippling is initially disabled. If it's
enabled, a rasterized polygon fragment with window coordinates x w and y w is sent
to the next stage of the GL if and only if the ( x w% 32)th bit in the ( y w% 32)th
row of the stipple pattern is 1 (one). When polygon stippling is disabled, it is as
if the stipple pattern consists of all 1's.
See external documentation.
getPolygonStipple() -> binary()
Return the polygon stipple pattern
gl:getPolygonStipple returns to Pattern a 32×32 polygon stipple pattern. The
pattern is packed into memory as if gl:readPixels/7 with both height and width of
32, type of ?GL_BITMAP, and format of ?GL_COLOR_INDEX were called, and the stipple
pattern were stored in an internal 32×32 color index buffer. Unlike gl:readPixels/7
, however, pixel transfer operations (shift, offset, pixel map) are not applied to
the returned stipple image.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a polygon stipple pattern is requested, Pattern is treated
as a byte offset into the buffer object's data store.
See external documentation.
edgeFlag(Flag) -> ok
Types:
Flag = 0 | 1
Flag edges as either boundary or nonboundary
Each vertex of a polygon, separate triangle, or separate quadrilateral specified
between a gl:'begin'/1 / gl:'begin'/1 pair is marked as the start of either a
boundary or nonboundary edge. If the current edge flag is true when the vertex is
specified, the vertex is marked as the start of a boundary edge. Otherwise, the
vertex is marked as the start of a nonboundary edge. gl:edgeFlag sets the edge flag
bit to ?GL_TRUE if Flag is ?GL_TRUE and to ?GL_FALSE otherwise.
The vertices of connected triangles and connected quadrilaterals are always marked
as boundary, regardless of the value of the edge flag.
Boundary and nonboundary edge flags on vertices are significant only if
?GL_POLYGON_MODE is set to ?GL_POINT or ?GL_LINE. See gl:polygonMode/2 .
See external documentation.
edgeFlagv(Flag) -> ok
Types:
Flag = {Flag::0 | 1}
Equivalent to edgeFlag(Flag).
scissor(X, Y, Width, Height) -> ok
Types:
X = integer()
Y = integer()
Width = integer()
Height = integer()
Define the scissor box
gl:scissor defines a rectangle, called the scissor box, in window coordinates. The
first two arguments, X and Y , specify the lower left corner of the box. Width and
Height specify the width and height of the box.
To enable and disable the scissor test, call gl:enable/1 and gl:enable/1 with
argument ?GL_SCISSOR_TEST. The test is initially disabled. While the test is
enabled, only pixels that lie within the scissor box can be modified by drawing
commands. Window coordinates have integer values at the shared corners of frame
buffer pixels. glScissor(0,0,1,1) allows modification of only the lower left pixel
in the window, and glScissor(0,0,0,0) doesn't allow modification of any pixels in
the window.
When the scissor test is disabled, it is as though the scissor box includes the
entire window.
See external documentation.
clipPlane(Plane, Equation) -> ok
Types:
Plane = enum()
Equation = {float(), float(), float(), float()}
Specify a plane against which all geometry is clipped
Geometry is always clipped against the boundaries of a six-plane frustum in x, y ,
and z. gl:clipPlane allows the specification of additional planes, not necessarily
perpendicular to the x, y, or z axis, against which all geometry is clipped. To
determine the maximum number of additional clipping planes, call gl:getBooleanv/1
with argument ?GL_MAX_CLIP_PLANES. All implementations support at least six such
clipping planes. Because the resulting clipping region is the intersection of the
defined half-spaces, it is always convex.
gl:clipPlane specifies a half-space using a four-component plane equation. When
gl:clipPlane is called, Equation is transformed by the inverse of the modelview
matrix and stored in the resulting eye coordinates. Subsequent changes to the
modelview matrix have no effect on the stored plane-equation components. If the dot
product of the eye coordinates of a vertex with the stored plane equation
components is positive or zero, the vertex is in with respect to that clipping
plane. Otherwise, it is out.
To enable and disable clipping planes, call gl:enable/1 and gl:enable/1 with the
argument ?GL_CLIP_PLANEi, where i is the plane number.
All clipping planes are initially defined as (0, 0, 0, 0) in eye coordinates and
are disabled.
See external documentation.
getClipPlane(Plane) -> {float(), float(), float(), float()}
Types:
Plane = enum()
Return the coefficients of the specified clipping plane
gl:getClipPlane returns in Equation the four coefficients of the plane equation for
Plane .
See external documentation.
drawBuffer(Mode) -> ok
Types:
Mode = enum()
Specify which color buffers are to be drawn into
When colors are written to the frame buffer, they are written into the color
buffers specified by gl:drawBuffer. The specifications are as follows:
?GL_NONE: No color buffers are written.
?GL_FRONT_LEFT: Only the front left color buffer is written.
?GL_FRONT_RIGHT: Only the front right color buffer is written.
?GL_BACK_LEFT: Only the back left color buffer is written.
?GL_BACK_RIGHT: Only the back right color buffer is written.
?GL_FRONT: Only the front left and front right color buffers are written. If there
is no front right color buffer, only the front left color buffer is written.
?GL_BACK: Only the back left and back right color buffers are written. If there is
no back right color buffer, only the back left color buffer is written.
?GL_LEFT: Only the front left and back left color buffers are written. If there is
no back left color buffer, only the front left color buffer is written.
?GL_RIGHT: Only the front right and back right color buffers are written. If there
is no back right color buffer, only the front right color buffer is written.
?GL_FRONT_AND_BACK: All the front and back color buffers (front left, front right,
back left, back right) are written. If there are no back color buffers, only the
front left and front right color buffers are written. If there are no right color
buffers, only the front left and back left color buffers are written. If there are
no right or back color buffers, only the front left color buffer is written.
If more than one color buffer is selected for drawing, then blending or logical
operations are computed and applied independently for each color buffer and can
produce different results in each buffer.
Monoscopic contexts include only left buffers, and stereoscopic contexts include
both left and right buffers. Likewise, single-buffered contexts include only front
buffers, and double-buffered contexts include both front and back buffers. The
context is selected at GL initialization.
See external documentation.
readBuffer(Mode) -> ok
Types:
Mode = enum()
Select a color buffer source for pixels
gl:readBuffer specifies a color buffer as the source for subsequent gl:readPixels/7
, gl:copyTexImage1D/7 , gl:copyTexImage2D/8 , gl:copyTexSubImage1D/6 ,
gl:copyTexSubImage2D/8 , and gl:copyTexSubImage3D/9 commands. Mode accepts one of
twelve or more predefined values. In a fully configured system, ?GL_FRONT,
?GL_LEFT, and ?GL_FRONT_LEFT all name the front left buffer, ?GL_FRONT_RIGHT and
?GL_RIGHT name the front right buffer, and ?GL_BACK_LEFT and ?GL_BACK name the back
left buffer. Further more, the constants ?GL_COLOR_ATTACHMENTi may be used to
indicate the ith color attachment where i ranges from zero to the value of
?GL_MAX_COLOR_ATTACHMENTS minus one.
Nonstereo double-buffered configurations have only a front left and a back left
buffer. Single-buffered configurations have a front left and a front right buffer
if stereo, and only a front left buffer if nonstereo. It is an error to specify a
nonexistent buffer to gl:readBuffer .
Mode is initially ?GL_FRONT in single-buffered configurations and ?GL_BACK in
double-buffered configurations.
See external documentation.
enable(Cap) -> ok
Types:
Cap = enum()
Enable or disable server-side GL capabilities
gl:enable and gl:enable/1 enable and disable various capabilities. Use
gl:isEnabled/1 or gl:getBooleanv/1 to determine the current setting of any
capability. The initial value for each capability with the exception of ?GL_DITHER
and ?GL_MULTISAMPLE is ?GL_FALSE. The initial value for ?GL_DITHER and
?GL_MULTISAMPLE is ?GL_TRUE.
Both gl:enable and gl:enable/1 take a single argument, Cap , which can assume one
of the following values:
Some of the GL's capabilities are indexed. gl:enablei and gl:disablei enable and
disable indexed capabilities.
?GL_BLEND: If enabled, blend the computed fragment color values with the values in
the color buffers. See gl:blendFunc/2 .
?GL_CLIP_DISTANCEi: If enabled, clip geometry against user-defined half space i.
?GL_COLOR_LOGIC_OP: If enabled, apply the currently selected logical operation to
the computed fragment color and color buffer values. See gl:logicOp/1 .
?GL_CULL_FACE: If enabled, cull polygons based on their winding in window
coordinates. See gl:cullFace/1 .
?GL_DEPTH_CLAMP: If enabled, the -w c≤ z c≤ w c plane equation is ignored by
view volume clipping (effectively, there is no near or far plane clipping). See
gl:depthRange/2 .
?GL_DEPTH_TEST: If enabled, do depth comparisons and update the depth buffer. Note
that even if the depth buffer exists and the depth mask is non-zero, the depth
buffer is not updated if the depth test is disabled. See gl:depthFunc/1 and
gl:depthRange/2 .
?GL_DITHER: If enabled, dither color components or indices before they are written
to the color buffer.
?GL_FRAMEBUFFER_SRGB: If enabled and the value of
?GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING for the framebuffer attachment
corresponding to the destination buffer is ?GL_SRGB, the R, G, and B destination
color values (after conversion from fixed-point to floating-point) are considered
to be encoded for the sRGB color space and hence are linearized prior to their use
in blending.
?GL_LINE_SMOOTH: If enabled, draw lines with correct filtering. Otherwise, draw
aliased lines. See gl:lineWidth/1 .
?GL_MULTISAMPLE: If enabled, use multiple fragment samples in computing the final
color of a pixel. See gl:sampleCoverage/2 .
?GL_POLYGON_OFFSET_FILL: If enabled, and if the polygon is rendered in ?GL_FILL
mode, an offset is added to depth values of a polygon's fragments before the depth
comparison is performed. See gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_LINE: If enabled, and if the polygon is rendered in ?GL_LINE
mode, an offset is added to depth values of a polygon's fragments before the depth
comparison is performed. See gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_POINT: If enabled, an offset is added to depth values of a
polygon's fragments before the depth comparison is performed, if the polygon is
rendered in ?GL_POINT mode. See gl:polygonOffset/2 .
?GL_POLYGON_SMOOTH: If enabled, draw polygons with proper filtering. Otherwise,
draw aliased polygons. For correct antialiased polygons, an alpha buffer is needed
and the polygons must be sorted front to back.
?GL_PRIMITIVE_RESTART: Enables primitive restarting. If enabled, any one of the
draw commands which transfers a set of generic attribute array elements to the GL
will restart the primitive when the index of the vertex is equal to the primitive
restart index. See gl:primitiveRestartIndex/1 .
?GL_SAMPLE_ALPHA_TO_COVERAGE: If enabled, compute a temporary coverage value where
each bit is determined by the alpha value at the corresponding sample location. The
temporary coverage value is then ANDed with the fragment coverage value.
?GL_SAMPLE_ALPHA_TO_ONE: If enabled, each sample alpha value is replaced by the
maximum representable alpha value.
?GL_SAMPLE_COVERAGE: If enabled, the fragment's coverage is ANDed with the
temporary coverage value. If ?GL_SAMPLE_COVERAGE_INVERT is set to ?GL_TRUE, invert
the coverage value. See gl:sampleCoverage/2 .
?GL_SAMPLE_SHADING: If enabled, the active fragment shader is run once for each
covered sample, or at fraction of this rate as determined by the current value of
?GL_MIN_SAMPLE_SHADING_VALUE . See gl:minSampleShading/1 .
?GL_SAMPLE_MASK: If enabled, the sample coverage mask generated for a fragment
during rasterization will be ANDed with the value of ?GL_SAMPLE_MASK_VALUE before
shading occurs. See gl:sampleMaski/2 .
?GL_SCISSOR_TEST: If enabled, discard fragments that are outside the scissor
rectangle. See gl:scissor/4 .
?GL_STENCIL_TEST: If enabled, do stencil testing and update the stencil buffer. See
gl:stencilFunc/3 and gl:stencilOp/3 .
?GL_TEXTURE_CUBE_MAP_SEAMLESS: If enabled, cubemap textures are sampled such that
when linearly sampling from the border between two adjacent faces, texels from both
faces are used to generate the final sample value. When disabled, texels from only
a single face are used to construct the final sample value.
?GL_PROGRAM_POINT_SIZE: If enabled and a vertex or geometry shader is active, then
the derived point size is taken from the (potentially clipped) shader builtin
?gl_PointSize and clamped to the implementation-dependent point size range.
See external documentation.
disable(Cap) -> ok
Types:
Cap = enum()
See enable/1
isEnabled(Cap) -> 0 | 1
Types:
Cap = enum()
Test whether a capability is enabled
gl:isEnabled returns ?GL_TRUE if Cap is an enabled capability and returns ?GL_FALSE
otherwise. Boolean states that are indexed may be tested with gl:isEnabledi . For
gl:isEnabledi, Index specifies the index of the capability to test. Index must be
between zero and the count of indexed capabilities for Cap . Initially all
capabilities except ?GL_DITHER are disabled; ?GL_DITHER is initially enabled.
The following capabilities are accepted for Cap :ConstantSee
?GL_BLENDgl:blendFunc/2 , gl:logicOp/1
?GL_CLIP_DISTANCEigl:enable/1
?GL_COLOR_LOGIC_OPgl:logicOp/1
?GL_CULL_FACEgl:cullFace/1
?GL_DEPTH_CLAMPgl:enable/1
?GL_DEPTH_TESTgl:depthFunc/1 , gl:depthRange/2
?GL_DITHERgl:enable/1
?GL_FRAMEBUFFER_SRGBgl:enable/1
?GL_LINE_SMOOTHgl:lineWidth/1
?GL_MULTISAMPLEgl:sampleCoverage/2
?GL_POLYGON_SMOOTHgl:polygonMode/2
?GL_POLYGON_OFFSET_FILLgl:polygonOffset/2
?GL_POLYGON_OFFSET_LINEgl:polygonOffset/2
?GL_POLYGON_OFFSET_POINTgl:polygonOffset/2
?GL_PROGRAM_POINT_SIZEgl:enable/1
?GL_PRIMITIVE_RESTARTgl:enable/1 , gl:primitiveRestartIndex/1
?GL_SAMPLE_ALPHA_TO_COVERAGEgl:sampleCoverage/2
?GL_SAMPLE_ALPHA_TO_ONEgl:sampleCoverage/2
?GL_SAMPLE_COVERAGEgl:sampleCoverage/2
?GL_SAMPLE_MASKgl:enable/1
?GL_SCISSOR_TESTgl:scissor/4
?GL_STENCIL_TESTgl:stencilFunc/3 , gl:stencilOp/3
?GL_TEXTURE_CUBEMAP_SEAMLESSgl:enable/1
See external documentation.
enableClientState(Cap) -> ok
Types:
Cap = enum()
Enable or disable client-side capability
gl:enableClientState and gl:enableClientState/1 enable or disable individual
client-side capabilities. By default, all client-side capabilities are disabled.
Both gl:enableClientState and gl:enableClientState/1 take a single argument, Cap ,
which can assume one of the following values:
?GL_COLOR_ARRAY: If enabled, the color array is enabled for writing and used during
rendering when gl:arrayElement/1 , gl:drawArrays/3 , gl:drawElements/4 ,
gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see glMultiDrawElements is called.
See gl:colorPointer/4 .
?GL_EDGE_FLAG_ARRAY: If enabled, the edge flag array is enabled for writing and
used during rendering when gl:arrayElement/1 , gl:drawArrays/3 , gl:drawElements/4
, gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see glMultiDrawElements is
called. See gl:edgeFlagPointer/2 .
?GL_FOG_COORD_ARRAY: If enabled, the fog coordinate array is enabled for writing
and used during rendering when gl:arrayElement/1 , gl:drawArrays/3 ,
gl:drawElements/4 , gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see
glMultiDrawElements is called. See gl:fogCoordPointer/3 .
?GL_INDEX_ARRAY: If enabled, the index array is enabled for writing and used during
rendering when gl:arrayElement/1 , gl:drawArrays/3 , gl:drawElements/4 ,
gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see glMultiDrawElements is called.
See gl:indexPointer/3 .
?GL_NORMAL_ARRAY: If enabled, the normal array is enabled for writing and used
during rendering when gl:arrayElement/1 , gl:drawArrays/3 , gl:drawElements/4 ,
gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see glMultiDrawElements is called.
See gl:normalPointer/3 .
?GL_SECONDARY_COLOR_ARRAY: If enabled, the secondary color array is enabled for
writing and used during rendering when gl:arrayElement/1 , gl:drawArrays/3 ,
gl:drawElements/4 , gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see
glMultiDrawElements is called. See gl:colorPointer/4 .
?GL_TEXTURE_COORD_ARRAY: If enabled, the texture coordinate array is enabled for
writing and used during rendering when gl:arrayElement/1 , gl:drawArrays/3 ,
gl:drawElements/4 , gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see
glMultiDrawElements is called. See gl:texCoordPointer/4 .
?GL_VERTEX_ARRAY: If enabled, the vertex array is enabled for writing and used
during rendering when gl:arrayElement/1 , gl:drawArrays/3 , gl:drawElements/4 ,
gl:drawRangeElements/6 gl:multiDrawArrays/3 , or see glMultiDrawElements is called.
See gl:vertexPointer/4 .
See external documentation.
disableClientState(Cap) -> ok
Types:
Cap = enum()
See enableClientState/1
getBooleanv(Pname) -> [0 | 1]
Types:
Pname = enum()
Return the value or values of a selected parameter
These four commands return values for simple state variables in GL. Pname is a
symbolic constant indicating the state variable to be returned, and Params is a
pointer to an array of the indicated type in which to place the returned data.
Type conversion is performed if Params has a different type than the state variable
value being requested. If gl:getBooleanv is called, a floating-point (or integer)
value is converted to ?GL_FALSE if and only if it is 0.0 (or 0). Otherwise, it is
converted to ?GL_TRUE. If gl:getIntegerv is called, boolean values are returned as
?GL_TRUE or ?GL_FALSE, and most floating-point values are rounded to the nearest
integer value. Floating-point colors and normals, however, are returned with a
linear mapping that maps 1.0 to the most positive representable integer value and
-1.0 to the most negative representable integer value. If gl:getFloatv or
gl:getDoublev is called, boolean values are returned as ?GL_TRUE or ?GL_FALSE, and
integer values are converted to floating-point values.
The following symbolic constants are accepted by Pname :
?GL_ACTIVE_TEXTURE: Params returns a single value indicating the active
multitexture unit. The initial value is ?GL_TEXTURE0. See gl:activeTexture/1 .
?GL_ALIASED_LINE_WIDTH_RANGE: Params returns a pair of values indicating the range
of widths supported for aliased lines. See gl:lineWidth/1 .
?GL_ARRAY_BUFFER_BINDING: Params returns a single value, the name of the buffer
object currently bound to the target ?GL_ARRAY_BUFFER. If no buffer object is bound
to this target, 0 is returned. The initial value is 0. See gl:bindBuffer/2 .
?GL_BLEND: Params returns a single boolean value indicating whether blending is
enabled. The initial value is ?GL_FALSE. See gl:blendFunc/2 .
?GL_BLEND_COLOR: Params returns four values, the red, green, blue, and alpha values
which are the components of the blend color. See gl:blendColor/4 .
?GL_BLEND_DST_ALPHA: Params returns one value, the symbolic constant identifying
the alpha destination blend function. The initial value is ?GL_ZERO. See
gl:blendFunc/2 and gl:blendFuncSeparate/4 .
?GL_BLEND_DST_RGB: Params returns one value, the symbolic constant identifying the
RGB destination blend function. The initial value is ?GL_ZERO. See gl:blendFunc/2
and gl:blendFuncSeparate/4 .
?GL_BLEND_EQUATION_RGB: Params returns one value, a symbolic constant indicating
whether the RGB blend equation is ?GL_FUNC_ADD, ?GL_FUNC_SUBTRACT,
?GL_FUNC_REVERSE_SUBTRACT , ?GL_MIN or ?GL_MAX. See gl:blendEquationSeparate/2 .
?GL_BLEND_EQUATION_ALPHA: Params returns one value, a symbolic constant indicating
whether the Alpha blend equation is ?GL_FUNC_ADD, ?GL_FUNC_SUBTRACT ,
?GL_FUNC_REVERSE_SUBTRACT, ?GL_MIN or ?GL_MAX. See gl:blendEquationSeparate/2 .
?GL_BLEND_SRC_ALPHA: Params returns one value, the symbolic constant identifying
the alpha source blend function. The initial value is ?GL_ONE. See gl:blendFunc/2
and gl:blendFuncSeparate/4 .
?GL_BLEND_SRC_RGB: Params returns one value, the symbolic constant identifying the
RGB source blend function. The initial value is ?GL_ONE. See gl:blendFunc/2 and
gl:blendFuncSeparate/4 .
?GL_COLOR_CLEAR_VALUE: Params returns four values: the red, green, blue, and alpha
values used to clear the color buffers. Integer values, if requested, are linearly
mapped from the internal floating-point representation such that 1.0 returns the
most positive representable integer value, and -1.0 returns the most negative
representable integer value. The initial value is (0, 0, 0, 0). See gl:clearColor/4
.
?GL_COLOR_LOGIC_OP: Params returns a single boolean value indicating whether a
fragment's RGBA color values are merged into the framebuffer using a logical
operation. The initial value is ?GL_FALSE. See gl:logicOp/1 .
?GL_COLOR_WRITEMASK: Params returns four boolean values: the red, green, blue, and
alpha write enables for the color buffers. The initial value is (?GL_TRUE,
?GL_TRUE, ?GL_TRUE, ?GL_TRUE). See gl:colorMask/4 .
?GL_COMPRESSED_TEXTURE_FORMATS: Params returns a list of symbolic constants of
length ?GL_NUM_COMPRESSED_TEXTURE_FORMATS indicating which compressed texture
formats are available. See gl:compressedTexImage2D/8 .
?GL_CONTEXT_FLAGS: Params returns one value, the flags with which the context was
created (such as debugging functionality).
?GL_CULL_FACE: Params returns a single boolean value indicating whether polygon
culling is enabled. The initial value is ?GL_FALSE. See gl:cullFace/1 .
?GL_CURRENT_PROGRAM: Params returns one value, the name of the program object that
is currently active, or 0 if no program object is active. See gl:useProgram/1 .
?GL_DEPTH_CLEAR_VALUE: Params returns one value, the value that is used to clear
the depth buffer. Integer values, if requested, are linearly mapped from the
internal floating-point representation such that 1.0 returns the most positive
representable integer value, and -1.0 returns the most negative representable
integer value. The initial value is 1. See gl:clearDepth/1 .
?GL_DEPTH_FUNC: Params returns one value, the symbolic constant that indicates the
depth comparison function. The initial value is ?GL_LESS. See gl:depthFunc/1 .
?GL_DEPTH_RANGE: Params returns two values: the near and far mapping limits for the
depth buffer. Integer values, if requested, are linearly mapped from the internal
floating-point representation such that 1.0 returns the most positive representable
integer value, and -1.0 returns the most negative representable integer value. The
initial value is (0, 1). See gl:depthRange/2 .
?GL_DEPTH_TEST: Params returns a single boolean value indicating whether depth
testing of fragments is enabled. The initial value is ?GL_FALSE. See gl:depthFunc/1
and gl:depthRange/2 .
?GL_DEPTH_WRITEMASK: Params returns a single boolean value indicating if the depth
buffer is enabled for writing. The initial value is ?GL_TRUE. See gl:depthMask/1 .
?GL_DITHER: Params returns a single boolean value indicating whether dithering of
fragment colors and indices is enabled. The initial value is ?GL_TRUE.
?GL_DOUBLEBUFFER: Params returns a single boolean value indicating whether double
buffering is supported.
?GL_DRAW_BUFFER: Params returns one value, a symbolic constant indicating which
buffers are being drawn to. See gl:drawBuffer/1 . The initial value is ?GL_BACK if
there are back buffers, otherwise it is ?GL_FRONT.
?GL_DRAW_BUFFERi: Params returns one value, a symbolic constant indicating which
buffers are being drawn to by the corresponding output color. See gl:drawBuffers/1
. The initial value of ?GL_DRAW_BUFFER0 is ?GL_BACK if there are back buffers,
otherwise it is ?GL_FRONT. The initial values of draw buffers for all other output
colors is ?GL_NONE.
?GL_DRAW_FRAMEBUFFER_BINDING: Params returns one value, the name of the framebuffer
object currently bound to the ?GL_DRAW_FRAMEBUFFER target. If the default
framebuffer is bound, this value will be zero. The initial value is zero. See
gl:bindFramebuffer/2 .
?GL_READ_FRAMEBUFFER_BINDING: Params returns one value, the name of the framebuffer
object currently bound to the ?GL_READ_FRAMEBUFFER target. If the default
framebuffer is bound, this value will be zero. The initial value is zero. See
gl:bindFramebuffer/2 .
?GL_ELEMENT_ARRAY_BUFFER_BINDING: Params returns a single value, the name of the
buffer object currently bound to the target ?GL_ELEMENT_ARRAY_BUFFER. If no buffer
object is bound to this target, 0 is returned. The initial value is 0. See
gl:bindBuffer/2 .
?GL_FRAGMENT_SHADER_DERIVATIVE_HINT: Params returns one value, a symbolic constant
indicating the mode of the derivative accuracy hint for fragment shaders. The
initial value is ?GL_DONT_CARE. See gl:hint/2 .
?GL_IMPLEMENTATION_COLOR_READ_FORMAT: Params returns a single GLenum value
indicating the implementation's preferred pixel data format. See gl:readPixels/7 .
?GL_IMPLEMENTATION_COLOR_READ_TYPE: Params returns a single GLenum value indicating
the implementation's preferred pixel data type. See gl:readPixels/7 .
?GL_LINE_SMOOTH: Params returns a single boolean value indicating whether
antialiasing of lines is enabled. The initial value is ?GL_FALSE. See
gl:lineWidth/1 .
?GL_LINE_SMOOTH_HINT: Params returns one value, a symbolic constant indicating the
mode of the line antialiasing hint. The initial value is ?GL_DONT_CARE. See
gl:hint/2 .
?GL_LINE_WIDTH: Params returns one value, the line width as specified with
gl:lineWidth/1 . The initial value is 1.
?GL_LAYER_PROVOKING_VERTEX: Params returns one value, the implementation dependent
specifc vertex of a primitive that is used to select the rendering layer. If the
value returned is equivalent to ?GL_PROVOKING_VERTEX, then the vertex selection
follows the convention specified by gl:provokingVertex/1 . If the value returned is
equivalent to ?GL_FIRST_VERTEX_CONVENTION, then the selection is always taken from
the first vertex in the primitive. If the value returned is equivalent to
?GL_LAST_VERTEX_CONVENTION , then the selection is always taken from the last
vertex in the primitive. If the value returned is equivalent to
?GL_UNDEFINED_VERTEX, then the selection is not guaranteed to be taken from any
specific vertex in the primitive.
?GL_LINE_WIDTH_GRANULARITY: Params returns one value, the width difference between
adjacent supported widths for antialiased lines. See gl:lineWidth/1 .
?GL_LINE_WIDTH_RANGE: Params returns two values: the smallest and largest supported
widths for antialiased lines. See gl:lineWidth/1 .
?GL_LOGIC_OP_MODE: Params returns one value, a symbolic constant indicating the
selected logic operation mode. The initial value is ?GL_COPY. See gl:logicOp/1 .
?GL_MAJOR_VERSION: Params returns one value, the major version number of the OpenGL
API supported by the current context.
?GL_MAX_3D_TEXTURE_SIZE: Params returns one value, a rough estimate of the largest
3D texture that the GL can handle. The value must be at least 64. Use
?GL_PROXY_TEXTURE_3D to determine if a texture is too large. See gl:texImage3D/10 .
?GL_MAX_ARRAY_TEXTURE_LAYERS: Params returns one value. The value indicates the
maximum number of layers allowed in an array texture, and must be at least 256. See
gl:texImage2D/9 .
?GL_MAX_CLIP_DISTANCES: Params returns one value, the maximum number of
application-defined clipping distances. The value must be at least 8.
?GL_MAX_COLOR_TEXTURE_SAMPLES: Params returns one value, the maximum number of
samples in a color multisample texture.
?GL_MAX_COMBINED_ATOMIC_COUNTERS: Params returns a single value, the maximum number
of atomic counters available to all active shaders.
?GL_MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS: Params returns one value, the number
of words for fragment shader uniform variables in all uniform blocks (including
default). The value must be at least 1. See gl:uniform1f/2 .
?GL_MAX_COMBINED_GEOMETRY_UNIFORM_COMPONENTS: Params returns one value, the number
of words for geometry shader uniform variables in all uniform blocks (including
default). The value must be at least 1. See gl:uniform1f/2 .
?GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS: Params returns one value, the maximum
supported texture image units that can be used to access texture maps from the
vertex shader and the fragment processor combined. If both the vertex shader and
the fragment processing stage access the same texture image unit, then that counts
as using two texture image units against this limit. The value must be at least 48.
See gl:activeTexture/1 .
?GL_MAX_COMBINED_UNIFORM_BLOCKS: Params returns one value, the maximum number of
uniform blocks per program. The value must be at least 36. See
gl:uniformBlockBinding/3 .
?GL_MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS: Params returns one value, the number of
words for vertex shader uniform variables in all uniform blocks (including
default). The value must be at least 1. See gl:uniform1f/2 .
?GL_MAX_CUBE_MAP_TEXTURE_SIZE: Params returns one value. The value gives a rough
estimate of the largest cube-map texture that the GL can handle. The value must be
at least 1024. Use ?GL_PROXY_TEXTURE_CUBE_MAP to determine if a texture is too
large. See gl:texImage2D/9 .
?GL_MAX_DEPTH_TEXTURE_SAMPLES: Params returns one value, the maximum number of
samples in a multisample depth or depth-stencil texture.
?GL_MAX_DRAW_BUFFERS: Params returns one value, the maximum number of simultaneous
outputs that may be written in a fragment shader. The value must be at least 8. See
gl:drawBuffers/1 .
?GL_MAX_DUALSOURCE_DRAW_BUFFERS: Params returns one value, the maximum number of
active draw buffers when using dual-source blending. The value must be at least 1.
See gl:blendFunc/2 and gl:blendFuncSeparate/4 .
?GL_MAX_ELEMENTS_INDICES: Params returns one value, the recommended maximum number
of vertex array indices. See gl:drawRangeElements/6 .
?GL_MAX_ELEMENTS_VERTICES: Params returns one value, the recommended maximum number
of vertex array vertices. See gl:drawRangeElements/6 .
?GL_MAX_FRAGMENT_ATOMIC_COUNTERS: Params returns a single value, the maximum number
of atomic counters available to fragment shaders.
?GL_MAX_FRAGMENT_INPUT_COMPONENTS: Params returns one value, the maximum number of
components of the inputs read by the fragment shader, which must be at least 128.
?GL_MAX_FRAGMENT_UNIFORM_COMPONENTS: Params returns one value, the maximum number
of individual floating-point, integer, or boolean values that can be held in
uniform variable storage for a fragment shader. The value must be at least 1024.
See gl:uniform1f/2 .
?GL_MAX_FRAGMENT_UNIFORM_VECTORS: Params returns one value, the maximum number of
individual 4-vectors of floating-point, integer, or boolean values that can be held
in uniform variable storage for a fragment shader. The value is equal to the value
of ?GL_MAX_FRAGMENT_UNIFORM_COMPONENTS divided by 4 and must be at least 256. See
gl:uniform1f/2 .
?GL_MAX_FRAGMENT_UNIFORM_BLOCKS: Params returns one value, the maximum number of
uniform blocks per fragment shader. The value must be at least 12. See
gl:uniformBlockBinding/3 .
?GL_MAX_GEOMETRY_ATOMIC_COUNTERS: Params returns a single value, the maximum number
of atomic counters available to geometry shaders.
?GL_MAX_GEOMETRY_INPUT_COMPONENTS: Params returns one value, the maximum number of
components of inputs read by a geometry shader, which must be at least 64.
?GL_MAX_GEOMETRY_OUTPUT_COMPONENTS: Params returns one value, the maximum number of
components of outputs written by a geometry shader, which must be at least 128.
?GL_MAX_GEOMETRY_TEXTURE_IMAGE_UNITS: Params returns one value, the maximum
supported texture image units that can be used to access texture maps from the
geometry shader. The value must be at least 16. See gl:activeTexture/1 .
?GL_MAX_GEOMETRY_UNIFORM_BLOCKS: Params returns one value, the maximum number of
uniform blocks per geometry shader. The value must be at least 12. See
gl:uniformBlockBinding/3 .
?GL_MAX_GEOMETRY_UNIFORM_COMPONENTS: Params returns one value, the maximum number
of individual floating-point, integer, or boolean values that can be held in
uniform variable storage for a geometry shader. The value must be at least 1024.
See gl:uniform1f/2 .
?GL_MAX_INTEGER_SAMPLES: Params returns one value, the maximum number of samples
supported in integer format multisample buffers.
?GL_MIN_MAP_BUFFER_ALIGNMENT: Params returns one value, the minimum alignment in
basic machine units of pointers returned fromsee glMapBuffer and see
glMapBufferRange . This value must be a power of two and must be at least 64.
?GL_MAX_PROGRAM_TEXEL_OFFSET: Params returns one value, the maximum texel offset
allowed in a texture lookup, which must be at least 7.
?GL_MIN_PROGRAM_TEXEL_OFFSET: Params returns one value, the minimum texel offset
allowed in a texture lookup, which must be at most -8.
?GL_MAX_RECTANGLE_TEXTURE_SIZE: Params returns one value. The value gives a rough
estimate of the largest rectangular texture that the GL can handle. The value must
be at least 1024. Use ?GL_PROXY_RECTANGLE_TEXTURE to determine if a texture is too
large. See gl:texImage2D/9 .
?GL_MAX_RENDERBUFFER_SIZE: Params returns one value. The value indicates the
maximum supported size for renderbuffers. See gl:framebufferRenderbuffer/4 .
?GL_MAX_SAMPLE_MASK_WORDS: Params returns one value, the maximum number of sample
mask words.
?GL_MAX_SERVER_WAIT_TIMEOUT: Params returns one value, the maximum gl:waitSync/3
timeout interval.
?GL_MAX_TESS_CONTROL_ATOMIC_COUNTERS: Params returns a single value, the maximum
number of atomic counters available to tessellation control shaders.
?GL_MAX_TESS_EVALUATION_ATOMIC_COUNTERS: Params returns a single value, the maximum
number of atomic counters available to tessellation evaluation shaders.
?GL_MAX_TEXTURE_BUFFER_SIZE: Params returns one value. The value gives the maximum
number of texels allowed in the texel array of a texture buffer object. Value must
be at least 65536.
?GL_MAX_TEXTURE_IMAGE_UNITS: Params returns one value, the maximum supported
texture image units that can be used to access texture maps from the fragment
shader. The value must be at least 16. See gl:activeTexture/1 .
?GL_MAX_TEXTURE_LOD_BIAS: Params returns one value, the maximum, absolute value of
the texture level-of-detail bias. The value must be at least 2.0.
?GL_MAX_TEXTURE_SIZE: Params returns one value. The value gives a rough estimate of
the largest texture that the GL can handle. The value must be at least 1024. Use a
proxy texture target such as ?GL_PROXY_TEXTURE_1D or ?GL_PROXY_TEXTURE_2D to
determine if a texture is too large. See gl:texImage1D/8 and gl:texImage2D/9 .
?GL_MAX_UNIFORM_BUFFER_BINDINGS: Params returns one value, the maximum number of
uniform buffer binding points on the context, which must be at least 36.
?GL_MAX_UNIFORM_BLOCK_SIZE: Params returns one value, the maximum size in basic
machine units of a uniform block, which must be at least 16384.
?GL_MAX_VARYING_COMPONENTS: Params returns one value, the number components for
varying variables, which must be at least 60.
?GL_MAX_VARYING_VECTORS: Params returns one value, the number 4-vectors for varying
variables, which is equal to the value of ?GL_MAX_VARYING_COMPONENTS and must be at
least 15.
?GL_MAX_VARYING_FLOATS: Params returns one value, the maximum number of
interpolators available for processing varying variables used by vertex and
fragment shaders. This value represents the number of individual floating-point
values that can be interpolated; varying variables declared as vectors, matrices,
and arrays will all consume multiple interpolators. The value must be at least 32.
?GL_MAX_VERTEX_ATOMIC_COUNTERS: Params returns a single value, the maximum number
of atomic counters available to vertex shaders.
?GL_MAX_VERTEX_ATTRIBS: Params returns one value, the maximum number of 4-component
generic vertex attributes accessible to a vertex shader. The value must be at least
16. See gl:vertexAttrib1d/2 .
?GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS: Params returns one value, the maximum supported
texture image units that can be used to access texture maps from the vertex shader.
The value may be at least 16. See gl:activeTexture/1 .
?GL_MAX_VERTEX_UNIFORM_COMPONENTS: Params returns one value, the maximum number of
individual floating-point, integer, or boolean values that can be held in uniform
variable storage for a vertex shader. The value must be at least 1024. See
gl:uniform1f/2 .
?GL_MAX_VERTEX_UNIFORM_VECTORS: Params returns one value, the maximum number of
4-vectors that may be held in uniform variable storage for the vertex shader. The
value of ?GL_MAX_VERTEX_UNIFORM_VECTORS is equal to the value of
?GL_MAX_VERTEX_UNIFORM_COMPONENTS and must be at least 256.
?GL_MAX_VERTEX_OUTPUT_COMPONENTS: Params returns one value, the maximum number of
components of output written by a vertex shader, which must be at least 64.
?GL_MAX_VERTEX_UNIFORM_BLOCKS: Params returns one value, the maximum number of
uniform blocks per vertex shader. The value must be at least 12. See
gl:uniformBlockBinding/3 .
?GL_MAX_VIEWPORT_DIMS: Params returns two values: the maximum supported width and
height of the viewport. These must be at least as large as the visible dimensions
of the display being rendered to. See gl:viewport/4 .
?GL_MAX_VIEWPORTS: Params returns one value, the maximum number of simultaneous
viewports that are supported. The value must be at least 16. See
gl:viewportIndexedf/5 .
?GL_MINOR_VERSION: Params returns one value, the minor version number of the OpenGL
API supported by the current context.
?GL_NUM_COMPRESSED_TEXTURE_FORMATS: Params returns a single integer value
indicating the number of available compressed texture formats. The minimum value is
4. See gl:compressedTexImage2D/8 .
?GL_NUM_EXTENSIONS: Params returns one value, the number of extensions supported by
the GL implementation for the current context. See gl:getString/1 .
?GL_NUM_PROGRAM_BINARY_FORMATS: Params returns one value, the number of program
binary formats supported by the implementation.
?GL_NUM_SHADER_BINARY_FORMATS: Params returns one value, the number of binary
shader formats supported by the implementation. If this value is greater than zero,
then the implementation supports loading binary shaders. If it is zero, then the
loading of binary shaders by the implementation is not supported.
?GL_PACK_ALIGNMENT: Params returns one value, the byte alignment used for writing
pixel data to memory. The initial value is 4. See gl:pixelStoref/2 .
?GL_PACK_IMAGE_HEIGHT: Params returns one value, the image height used for writing
pixel data to memory. The initial value is 0. See gl:pixelStoref/2 .
?GL_PACK_LSB_FIRST: Params returns a single boolean value indicating whether
single-bit pixels being written to memory are written first to the least
significant bit of each unsigned byte. The initial value is ?GL_FALSE. See
gl:pixelStoref/2 .
?GL_PACK_ROW_LENGTH: Params returns one value, the row length used for writing
pixel data to memory. The initial value is 0. See gl:pixelStoref/2 .
?GL_PACK_SKIP_IMAGES: Params returns one value, the number of pixel images skipped
before the first pixel is written into memory. The initial value is 0. See
gl:pixelStoref/2 .
?GL_PACK_SKIP_PIXELS: Params returns one value, the number of pixel locations
skipped before the first pixel is written into memory. The initial value is 0. See
gl:pixelStoref/2 .
?GL_PACK_SKIP_ROWS: Params returns one value, the number of rows of pixel locations
skipped before the first pixel is written into memory. The initial value is 0. See
gl:pixelStoref/2 .
?GL_PACK_SWAP_BYTES: Params returns a single boolean value indicating whether the
bytes of two-byte and four-byte pixel indices and components are swapped before
being written to memory. The initial value is ?GL_FALSE. See gl:pixelStoref/2 .
?GL_PIXEL_PACK_BUFFER_BINDING: Params returns a single value, the name of the
buffer object currently bound to the target ?GL_PIXEL_PACK_BUFFER. If no buffer
object is bound to this target, 0 is returned. The initial value is 0. See
gl:bindBuffer/2 .
?GL_PIXEL_UNPACK_BUFFER_BINDING: Params returns a single value, the name of the
buffer object currently bound to the target ?GL_PIXEL_UNPACK_BUFFER. If no buffer
object is bound to this target, 0 is returned. The initial value is 0. See
gl:bindBuffer/2 .
?GL_POINT_FADE_THRESHOLD_SIZE: Params returns one value, the point size threshold
for determining the point size. See gl:pointParameterf/2 .
?GL_PRIMITIVE_RESTART_INDEX: Params returns one value, the current primitive
restart index. The initial value is 0. See gl:primitiveRestartIndex/1 .
?GL_PROGRAM_BINARY_FORMATS: Params an array of ?GL_NUM_PROGRAM_BINARY_FORMATS
values, indicating the proram binary formats supported by the implementation.
?GL_PROGRAM_PIPELINE_BINDING: Params a single value, the name of the currently
bound program pipeline object, or zero if no program pipeline object is bound. See
gl:bindProgramPipeline/1 .
?GL_PROVOKING_VERTEX: Params returns one value, the currently selected provoking
vertex convention. The initial value is ?GL_LAST_VERTEX_CONVENTION. See
gl:provokingVertex/1 .
?GL_POINT_SIZE: Params returns one value, the point size as specified by
gl:pointSize/1 . The initial value is 1.
?GL_POINT_SIZE_GRANULARITY: Params returns one value, the size difference between
adjacent supported sizes for antialiased points. See gl:pointSize/1 .
?GL_POINT_SIZE_RANGE: Params returns two values: the smallest and largest supported
sizes for antialiased points. The smallest size must be at most 1, and the largest
size must be at least 1. See gl:pointSize/1 .
?GL_POLYGON_OFFSET_FACTOR: Params returns one value, the scaling factor used to
determine the variable offset that is added to the depth value of each fragment
generated when a polygon is rasterized. The initial value is 0. See
gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_UNITS: Params returns one value. This value is multiplied by an
implementation-specific value and then added to the depth value of each fragment
generated when a polygon is rasterized. The initial value is 0. See
gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_FILL: Params returns a single boolean value indicating whether
polygon offset is enabled for polygons in fill mode. The initial value is ?GL_FALSE
. See gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_LINE: Params returns a single boolean value indicating whether
polygon offset is enabled for polygons in line mode. The initial value is ?GL_FALSE
. See gl:polygonOffset/2 .
?GL_POLYGON_OFFSET_POINT: Params returns a single boolean value indicating whether
polygon offset is enabled for polygons in point mode. The initial value is
?GL_FALSE . See gl:polygonOffset/2 .
?GL_POLYGON_SMOOTH: Params returns a single boolean value indicating whether
antialiasing of polygons is enabled. The initial value is ?GL_FALSE. See
gl:polygonMode/2 .
?GL_POLYGON_SMOOTH_HINT: Params returns one value, a symbolic constant indicating
the mode of the polygon antialiasing hint. The initial value is ?GL_DONT_CARE. See
gl:hint/2 .
?GL_READ_BUFFER: Params returns one value, a symbolic constant indicating which
color buffer is selected for reading. The initial value is ?GL_BACK if there is a
back buffer, otherwise it is ?GL_FRONT. See gl:readPixels/7 .
?GL_RENDERBUFFER_BINDING: Params returns a single value, the name of the
renderbuffer object currently bound to the target ?GL_RENDERBUFFER. If no
renderbuffer object is bound to this target, 0 is returned. The initial value is 0.
See gl:bindRenderbuffer/2 .
?GL_SAMPLE_BUFFERS: Params returns a single integer value indicating the number of
sample buffers associated with the framebuffer. See gl:sampleCoverage/2 .
?GL_SAMPLE_COVERAGE_VALUE: Params returns a single positive floating-point value
indicating the current sample coverage value. See gl:sampleCoverage/2 .
?GL_SAMPLE_COVERAGE_INVERT: Params returns a single boolean value indicating if the
temporary coverage value should be inverted. See gl:sampleCoverage/2 .
?GL_SAMPLER_BINDING: Params returns a single value, the name of the sampler object
currently bound to the active texture unit. The initial value is 0. See
gl:bindSampler/2 .
?GL_SAMPLES: Params returns a single integer value indicating the coverage mask
size. See gl:sampleCoverage/2 .
?GL_SCISSOR_BOX: Params returns four values: the x and y window coordinates of the
scissor box, followed by its width and height. Initially the x and y window
coordinates are both 0 and the width and height are set to the size of the window.
See gl:scissor/4 .
?GL_SCISSOR_TEST: Params returns a single boolean value indicating whether
scissoring is enabled. The initial value is ?GL_FALSE. See gl:scissor/4 .
?GL_SHADER_COMPILER: Params returns a single boolean value indicating whether an
online shader compiler is present in the implementation. All desktop OpenGL
implementations must support online shader compilations, and therefore the value of
?GL_SHADER_COMPILER will always be ?GL_TRUE.
?GL_SMOOTH_LINE_WIDTH_RANGE: Params returns a pair of values indicating the range
of widths supported for smooth (antialiased) lines. See gl:lineWidth/1 .
?GL_SMOOTH_LINE_WIDTH_GRANULARITY: Params returns a single value indicating the
level of quantization applied to smooth line width parameters.
?GL_STENCIL_BACK_FAIL: Params returns one value, a symbolic constant indicating
what action is taken for back-facing polygons when the stencil test fails. The
initial value is ?GL_KEEP. See gl:stencilOpSeparate/4 .
?GL_STENCIL_BACK_FUNC: Params returns one value, a symbolic constant indicating
what function is used for back-facing polygons to compare the stencil reference
value with the stencil buffer value. The initial value is ?GL_ALWAYS. See
gl:stencilFuncSeparate/4 .
?GL_STENCIL_BACK_PASS_DEPTH_FAIL: Params returns one value, a symbolic constant
indicating what action is taken for back-facing polygons when the stencil test
passes, but the depth test fails. The initial value is ?GL_KEEP. See
gl:stencilOpSeparate/4 .
?GL_STENCIL_BACK_PASS_DEPTH_PASS: Params returns one value, a symbolic constant
indicating what action is taken for back-facing polygons when the stencil test
passes and the depth test passes. The initial value is ?GL_KEEP. See
gl:stencilOpSeparate/4 .
?GL_STENCIL_BACK_REF: Params returns one value, the reference value that is
compared with the contents of the stencil buffer for back-facing polygons. The
initial value is 0. See gl:stencilFuncSeparate/4 .
?GL_STENCIL_BACK_VALUE_MASK: Params returns one value, the mask that is used for
back-facing polygons to mask both the stencil reference value and the stencil
buffer value before they are compared. The initial value is all 1's. See
gl:stencilFuncSeparate/4 .
?GL_STENCIL_BACK_WRITEMASK: Params returns one value, the mask that controls
writing of the stencil bitplanes for back-facing polygons. The initial value is all
1's. See gl:stencilMaskSeparate/2 .
?GL_STENCIL_CLEAR_VALUE: Params returns one value, the index to which the stencil
bitplanes are cleared. The initial value is 0. See gl:clearStencil/1 .
?GL_STENCIL_FAIL: Params returns one value, a symbolic constant indicating what
action is taken when the stencil test fails. The initial value is ?GL_KEEP. See
gl:stencilOp/3 . This stencil state only affects non-polygons and front-facing
polygons. Back-facing polygons use separate stencil state. See
gl:stencilOpSeparate/4 .
?GL_STENCIL_FUNC: Params returns one value, a symbolic constant indicating what
function is used to compare the stencil reference value with the stencil buffer
value. The initial value is ?GL_ALWAYS. See gl:stencilFunc/3 . This stencil state
only affects non-polygons and front-facing polygons. Back-facing polygons use
separate stencil state. See gl:stencilFuncSeparate/4 .
?GL_STENCIL_PASS_DEPTH_FAIL: Params returns one value, a symbolic constant
indicating what action is taken when the stencil test passes, but the depth test
fails. The initial value is ?GL_KEEP. See gl:stencilOp/3 . This stencil state only
affects non-polygons and front-facing polygons. Back-facing polygons use separate
stencil state. See gl:stencilOpSeparate/4 .
?GL_STENCIL_PASS_DEPTH_PASS: Params returns one value, a symbolic constant
indicating what action is taken when the stencil test passes and the depth test
passes. The initial value is ?GL_KEEP. See gl:stencilOp/3 . This stencil state only
affects non-polygons and front-facing polygons. Back-facing polygons use separate
stencil state. See gl:stencilOpSeparate/4 .
?GL_STENCIL_REF: Params returns one value, the reference value that is compared
with the contents of the stencil buffer. The initial value is 0. See
gl:stencilFunc/3 . This stencil state only affects non-polygons and front-facing
polygons. Back-facing polygons use separate stencil state. See
gl:stencilFuncSeparate/4 .
?GL_STENCIL_TEST: Params returns a single boolean value indicating whether stencil
testing of fragments is enabled. The initial value is ?GL_FALSE. See
gl:stencilFunc/3 and gl:stencilOp/3 .
?GL_STENCIL_VALUE_MASK: Params returns one value, the mask that is used to mask
both the stencil reference value and the stencil buffer value before they are
compared. The initial value is all 1's. See gl:stencilFunc/3 . This stencil state
only affects non-polygons and front-facing polygons. Back-facing polygons use
separate stencil state. See gl:stencilFuncSeparate/4 .
?GL_STENCIL_WRITEMASK: Params returns one value, the mask that controls writing of
the stencil bitplanes. The initial value is all 1's. See gl:stencilMask/1 . This
stencil state only affects non-polygons and front-facing polygons. Back-facing
polygons use separate stencil state. See gl:stencilMaskSeparate/2 .
?GL_STEREO: Params returns a single boolean value indicating whether stereo buffers
(left and right) are supported.
?GL_SUBPIXEL_BITS: Params returns one value, an estimate of the number of bits of
subpixel resolution that are used to position rasterized geometry in window
coordinates. The value must be at least 4.
?GL_TEXTURE_BINDING_1D: Params returns a single value, the name of the texture
currently bound to the target ?GL_TEXTURE_1D. The initial value is 0. See
gl:bindTexture/2 .
?GL_TEXTURE_BINDING_1D_ARRAY: Params returns a single value, the name of the
texture currently bound to the target ?GL_TEXTURE_1D_ARRAY. The initial value is 0.
See gl:bindTexture/2 .
?GL_TEXTURE_BINDING_2D: Params returns a single value, the name of the texture
currently bound to the target ?GL_TEXTURE_2D. The initial value is 0. See
gl:bindTexture/2 .
?GL_TEXTURE_BINDING_2D_ARRAY: Params returns a single value, the name of the
texture currently bound to the target ?GL_TEXTURE_2D_ARRAY. The initial value is 0.
See gl:bindTexture/2 .
?GL_TEXTURE_BINDING_2D_MULTISAMPLE: Params returns a single value, the name of the
texture currently bound to the target ?GL_TEXTURE_2D_MULTISAMPLE. The initial value
is 0. See gl:bindTexture/2 .
?GL_TEXTURE_BINDING_2D_MULTISAMPLE_ARRAY: Params returns a single value, the name
of the texture currently bound to the target ?GL_TEXTURE_2D_MULTISAMPLE_ARRAY . The
initial value is 0. See gl:bindTexture/2 .
?GL_TEXTURE_BINDING_3D: Params returns a single value, the name of the texture
currently bound to the target ?GL_TEXTURE_3D. The initial value is 0. See
gl:bindTexture/2 .
?GL_TEXTURE_BINDING_BUFFER: Params returns a single value, the name of the texture
currently bound to the target ?GL_TEXTURE_BUFFER. The initial value is 0. See
gl:bindTexture/2 .
?GL_TEXTURE_BINDING_CUBE_MAP: Params returns a single value, the name of the
texture currently bound to the target ?GL_TEXTURE_CUBE_MAP. The initial value is 0.
See gl:bindTexture/2 .
?GL_TEXTURE_BINDING_RECTANGLE: Params returns a single value, the name of the
texture currently bound to the target ?GL_TEXTURE_RECTANGLE. The initial value is
0. See gl:bindTexture/2 .
?GL_TEXTURE_COMPRESSION_HINT: Params returns a single value indicating the mode of
the texture compression hint. The initial value is ?GL_DONT_CARE.
?GL_TEXTURE_BUFFER_BINDING: Params returns a single value, the name of the texture
buffer object currently bound. The initial value is 0. See gl:bindBuffer/2 .
?GL_TIMESTAMP: Params returns a single value, the 64-bit value of the current GL
time. See gl:queryCounter/2 .
?GL_TRANSFORM_FEEDBACK_BUFFER_BINDING: When used with non-indexed variants of
gl:get (such as gl:getIntegerv), Params returns a single value, the name of the
buffer object currently bound to the target ?GL_TRANSFORM_FEEDBACK_BUFFER. If no
buffer object is bound to this target, 0 is returned. When used with indexed
variants of gl:get (such as gl:getIntegeri_v), Params returns a single value, the
name of the buffer object bound to the indexed transform feedback attribute stream.
The initial value is 0 for all targets. See gl:bindBuffer/2 , gl:bindBufferBase/3 ,
and gl:bindBufferRange/5 .
?GL_TRANSFORM_FEEDBACK_BUFFER_START: When used with indexed variants of gl:get
(such as gl:getInteger64i_v), Params returns a single value, the start offset of
the binding range for each transform feedback attribute stream. The initial value
is 0 for all streams. See gl:bindBufferRange/5 .
?GL_TRANSFORM_FEEDBACK_BUFFER_SIZE: When used with indexed variants of gl:get (such
as gl:getInteger64i_v), Params returns a single value, the size of the binding
range for each transform feedback attribute stream. The initial value is 0 for all
streams. See gl:bindBufferRange/5 .
?GL_UNIFORM_BUFFER_BINDING: When used with non-indexed variants of gl:get (such as
gl:getIntegerv), Params returns a single value, the name of the buffer object
currently bound to the target ?GL_UNIFORM_BUFFER. If no buffer object is bound to
this target, 0 is returned. When used with indexed variants of gl:get (such as
gl:getIntegeri_v), Params returns a single value, the name of the buffer object
bound to the indexed uniform buffer binding point. The initial value is 0 for all
targets. See gl:bindBuffer/2 , gl:bindBufferBase/3 , and gl:bindBufferRange/5 .
?GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT: Params returns a single value, the minimum
required alignment for uniform buffer sizes and offset. The initial value is 1. See
gl:uniformBlockBinding/3 .
?GL_UNIFORM_BUFFER_SIZE: When used with indexed variants of gl:get (such as
gl:getInteger64i_v), Params returns a single value, the size of the binding range
for each indexed uniform buffer binding. The initial value is 0 for all bindings.
See gl:bindBufferRange/5 .
?GL_UNIFORM_BUFFER_START: When used with indexed variants of gl:get (such as
gl:getInteger64i_v), Params returns a single value, the start offset of the binding
range for each indexed uniform buffer binding. The initial value is 0 for all
bindings. See gl:bindBufferRange/5 .
?GL_UNPACK_ALIGNMENT: Params returns one value, the byte alignment used for reading
pixel data from memory. The initial value is 4. See gl:pixelStoref/2 .
?GL_UNPACK_IMAGE_HEIGHT: Params returns one value, the image height used for
reading pixel data from memory. The initial is 0. See gl:pixelStoref/2 .
?GL_UNPACK_LSB_FIRST: Params returns a single boolean value indicating whether
single-bit pixels being read from memory are read first from the least significant
bit of each unsigned byte. The initial value is ?GL_FALSE. See gl:pixelStoref/2 .
?GL_UNPACK_ROW_LENGTH: Params returns one value, the row length used for reading
pixel data from memory. The initial value is 0. See gl:pixelStoref/2 .
?GL_UNPACK_SKIP_IMAGES: Params returns one value, the number of pixel images
skipped before the first pixel is read from memory. The initial value is 0. See
gl:pixelStoref/2 .
?GL_UNPACK_SKIP_PIXELS: Params returns one value, the number of pixel locations
skipped before the first pixel is read from memory. The initial value is 0. See
gl:pixelStoref/2 .
?GL_UNPACK_SKIP_ROWS: Params returns one value, the number of rows of pixel
locations skipped before the first pixel is read from memory. The initial value is
0. See gl:pixelStoref/2 .
?GL_UNPACK_SWAP_BYTES: Params returns a single boolean value indicating whether the
bytes of two-byte and four-byte pixel indices and components are swapped after
being read from memory. The initial value is ?GL_FALSE. See gl:pixelStoref/2 .
?GL_VERTEX_PROGRAM_POINT_SIZE: Params returns a single boolean value indicating
whether vertex program point size mode is enabled. If enabled, and a vertex shader
is active, then the point size is taken from the shader built-in gl_PointSize. If
disabled, and a vertex shader is active, then the point size is taken from the
point state as specified by gl:pointSize/1 . The initial value is ?GL_FALSE.
?GL_VIEWPORT: When used with non-indexed variants of gl:get (such as gl:getIntegerv
), Params returns four values: the x and y window coordinates of the viewport,
followed by its width and height. Initially the x and y window coordinates are both
set to 0, and the width and height are set to the width and height of the window
into which the GL will do its rendering. See gl:viewport/4 . When used with indexed
variants of gl:get (such as gl:getIntegeri_v), Params returns four values: the x
and y window coordinates of the indexed viewport, followed by its width and height.
Initially the x and y window coordinates are both set to 0, and the width and
height are set to the width and height of the window into which the GL will do its
rendering. See gl:viewportIndexedf/5 .
?GL_VIEWPORT_BOUNDS_RANGE: Params returns two values, the minimum and maximum
viewport bounds range. The minimum range should be at least [-32768, 32767].
?GL_VIEWPORT_INDEX_PROVOKING_VERTEX: Params returns one value, the implementation
dependent specifc vertex of a primitive that is used to select the viewport index.
If the value returned is equivalent to ?GL_PROVOKING_VERTEX, then the vertex
selection follows the convention specified by gl:provokingVertex/1 . If the value
returned is equivalent to ?GL_FIRST_VERTEX_CONVENTION, then the selection is always
taken from the first vertex in the primitive. If the value returned is equivalent
to ?GL_LAST_VERTEX_CONVENTION , then the selection is always taken from the last
vertex in the primitive. If the value returned is equivalent to
?GL_UNDEFINED_VERTEX, then the selection is not guaranteed to be taken from any
specific vertex in the primitive.
?GL_VIEWPORT_SUBPIXEL_BITS: Params returns a single value, the number of bits of
sub-pixel precision which the GL uses to interpret the floating point viewport
bounds. The minimum value is 0.
Many of the boolean parameters can also be queried more easily using gl:isEnabled/1
.
See external documentation.
getDoublev(Pname) -> [float()]
Types:
Pname = enum()
See getBooleanv/1
getFloatv(Pname) -> [float()]
Types:
Pname = enum()
See getBooleanv/1
getIntegerv(Pname) -> [integer()]
Types:
Pname = enum()
See getBooleanv/1
pushAttrib(Mask) -> ok
Types:
Mask = integer()
Push and pop the server attribute stack
gl:pushAttrib takes one argument, a mask that indicates which groups of state
variables to save on the attribute stack. Symbolic constants are used to set bits
in the mask. Mask is typically constructed by specifying the bitwise-or of several
of these constants together. The special mask ?GL_ALL_ATTRIB_BITS can be used to
save all stackable states.
The symbolic mask constants and their associated GL state are as follows (the
second column lists which attributes are saved):?GL_ACCUM_BUFFER_BIT Accumulation
buffer clear value
?GL_COLOR_BUFFER_BIT?GL_ALPHA_TEST enable bit
Alpha test function and reference value
?GL_BLEND enable bit
Blending source and destination functions
Constant blend color
Blending equation
?GL_DITHER enable bit
?GL_DRAW_BUFFER setting
?GL_COLOR_LOGIC_OP enable bit
?GL_INDEX_LOGIC_OP enable bit
Logic op function
Color mode and index mode clear values
Color mode and index mode writemasks
?GL_CURRENT_BIT Current RGBA color
Current color index
Current normal vector
Current texture coordinates
Current raster position
?GL_CURRENT_RASTER_POSITION_VALID flag
RGBA color associated with current raster position
Color index associated with current raster position
Texture coordinates associated with current raster position
?GL_EDGE_FLAG flag
?GL_DEPTH_BUFFER_BIT?GL_DEPTH_TEST enable bit
Depth buffer test function
Depth buffer clear value
?GL_DEPTH_WRITEMASK enable bit
?GL_ENABLE_BIT?GL_ALPHA_TEST flag
?GL_AUTO_NORMAL flag
?GL_BLEND flag
Enable bits for the user-definable clipping planes
?GL_COLOR_MATERIAL
?GL_CULL_FACE flag
?GL_DEPTH_TEST flag
?GL_DITHER flag
?GL_FOG flag
?GL_LIGHTi where ?0 <= i < ?GL_MAX_LIGHTS
?GL_LIGHTING flag
?GL_LINE_SMOOTH flag
?GL_LINE_STIPPLE flag
?GL_COLOR_LOGIC_OP flag
?GL_INDEX_LOGIC_OP flag
?GL_MAP1_x where x is a map type
?GL_MAP2_x where x is a map type
?GL_MULTISAMPLE flag
?GL_NORMALIZE flag
?GL_POINT_SMOOTH flag
?GL_POLYGON_OFFSET_LINE flag
?GL_POLYGON_OFFSET_FILL flag
?GL_POLYGON_OFFSET_POINT flag
?GL_POLYGON_SMOOTH flag
?GL_POLYGON_STIPPLE flag
?GL_SAMPLE_ALPHA_TO_COVERAGE flag
?GL_SAMPLE_ALPHA_TO_ONE flag
?GL_SAMPLE_COVERAGE flag
?GL_SCISSOR_TEST flag
?GL_STENCIL_TEST flag
?GL_TEXTURE_1D flag
?GL_TEXTURE_2D flag
?GL_TEXTURE_3D flag
Flags ?GL_TEXTURE_GEN_x where x is S, T, R, or Q
?GL_EVAL_BIT?GL_MAP1_x enable bits, where x is a map type
?GL_MAP2_x enable bits, where x is a map type
1D grid endpoints and divisions
2D grid endpoints and divisions
?GL_AUTO_NORMAL enable bit
?GL_FOG_BIT?GL_FOG enable bit
Fog color
Fog density
Linear fog start
Linear fog end
Fog index
?GL_FOG_MODE value
?GL_HINT_BIT?GL_PERSPECTIVE_CORRECTION_HINT setting
?GL_POINT_SMOOTH_HINT setting
?GL_LINE_SMOOTH_HINT setting
?GL_POLYGON_SMOOTH_HINT setting
?GL_FOG_HINT setting
?GL_GENERATE_MIPMAP_HINT setting
?GL_TEXTURE_COMPRESSION_HINT setting
?GL_LIGHTING_BIT?GL_COLOR_MATERIAL enable bit
?GL_COLOR_MATERIAL_FACE value
Color material parameters that are tracking the current color
Ambient scene color
?GL_LIGHT_MODEL_LOCAL_VIEWER value
?GL_LIGHT_MODEL_TWO_SIDE setting
?GL_LIGHTING enable bit
Enable bit for each light
Ambient, diffuse, and specular intensity for each light
Direction, position, exponent, and cutoff angle for each light
Constant, linear, and quadratic attenuation factors for each light
Ambient, diffuse, specular, and emissive color for each material
Ambient, diffuse, and specular color indices for each material
Specular exponent for each material
?GL_SHADE_MODEL setting
?GL_LINE_BIT?GL_LINE_SMOOTH flag
?GL_LINE_STIPPLE enable bit
Line stipple pattern and repeat counter
Line width
?GL_LIST_BIT?GL_LIST_BASE setting
?GL_MULTISAMPLE_BIT?GL_MULTISAMPLE flag
?GL_SAMPLE_ALPHA_TO_COVERAGE flag
?GL_SAMPLE_ALPHA_TO_ONE flag
?GL_SAMPLE_COVERAGE flag
?GL_SAMPLE_COVERAGE_VALUE value
?GL_SAMPLE_COVERAGE_INVERT value
?GL_PIXEL_MODE_BIT?GL_RED_BIAS and ?GL_RED_SCALE settings
?GL_GREEN_BIAS and ?GL_GREEN_SCALE values
?GL_BLUE_BIAS and ?GL_BLUE_SCALE
?GL_ALPHA_BIAS and ?GL_ALPHA_SCALE
?GL_DEPTH_BIAS and ?GL_DEPTH_SCALE
?GL_INDEX_OFFSET and ?GL_INDEX_SHIFT values
?GL_MAP_COLOR and ?GL_MAP_STENCIL flags
?GL_ZOOM_X and ?GL_ZOOM_Y factors
?GL_READ_BUFFER setting
?GL_POINT_BIT?GL_POINT_SMOOTH flag
Point size
?GL_POLYGON_BIT?GL_CULL_FACE enable bit
?GL_CULL_FACE_MODE value
?GL_FRONT_FACE indicator
?GL_POLYGON_MODE setting
?GL_POLYGON_SMOOTH flag
?GL_POLYGON_STIPPLE enable bit
?GL_POLYGON_OFFSET_FILL flag
?GL_POLYGON_OFFSET_LINE flag
?GL_POLYGON_OFFSET_POINT flag
?GL_POLYGON_OFFSET_FACTOR
?GL_POLYGON_OFFSET_UNITS
?GL_POLYGON_STIPPLE_BIT Polygon stipple image
?GL_SCISSOR_BIT?GL_SCISSOR_TEST flag
Scissor box
?GL_STENCIL_BUFFER_BIT?GL_STENCIL_TEST enable bit
Stencil function and reference value
Stencil value mask
Stencil fail, pass, and depth buffer pass actions
Stencil buffer clear value
Stencil buffer writemask
?GL_TEXTURE_BIT Enable bits for the four texture coordinates
Border color for each texture image
Minification function for each texture image
Magnification function for each texture image
Texture coordinates and wrap mode for each texture image
Color and mode for each texture environment
Enable bits ?GL_TEXTURE_GEN_x, x is S, T, R, and Q
?GL_TEXTURE_GEN_MODE setting for S, T, R, and Q
gl:texGend/3 plane equations for S, T, R, and Q
Current texture bindings (for example, ?GL_TEXTURE_BINDING_2D)
?GL_TRANSFORM_BIT Coefficients of the six clipping planes
Enable bits for the user-definable clipping planes
?GL_MATRIX_MODE value
?GL_NORMALIZE flag
?GL_RESCALE_NORMAL flag
?GL_VIEWPORT_BIT Depth range (near and far)
Viewport origin and extent
gl:pushAttrib/1 restores the values of the state variables saved with the last
gl:pushAttrib command. Those not saved are left unchanged.
It is an error to push attributes onto a full stack or to pop attributes off an
empty stack. In either case, the error flag is set and no other change is made to
GL state.
Initially, the attribute stack is empty.
See external documentation.
popAttrib() -> ok
See pushAttrib/1
pushClientAttrib(Mask) -> ok
Types:
Mask = integer()
Push and pop the client attribute stack
gl:pushClientAttrib takes one argument, a mask that indicates which groups of
client-state variables to save on the client attribute stack. Symbolic constants
are used to set bits in the mask. Mask is typically constructed by specifying the
bitwise-or of several of these constants together. The special mask
?GL_CLIENT_ALL_ATTRIB_BITS can be used to save all stackable client state.
The symbolic mask constants and their associated GL client state are as follows
(the second column lists which attributes are saved):
?GL_CLIENT_PIXEL_STORE_BIT Pixel storage modes ?GL_CLIENT_VERTEX_ARRAY_BIT Vertex
arrays (and enables)
gl:pushClientAttrib/1 restores the values of the client-state variables saved with
the last gl:pushClientAttrib. Those not saved are left unchanged.
It is an error to push attributes onto a full client attribute stack or to pop
attributes off an empty stack. In either case, the error flag is set, and no other
change is made to GL state.
Initially, the client attribute stack is empty.
See external documentation.
popClientAttrib() -> ok
See pushClientAttrib/1
renderMode(Mode) -> integer()
Types:
Mode = enum()
Set rasterization mode
gl:renderMode sets the rasterization mode. It takes one argument, Mode , which can
assume one of three predefined values:
?GL_RENDER: Render mode. Primitives are rasterized, producing pixel fragments,
which are written into the frame buffer. This is the normal mode and also the
default mode.
?GL_SELECT: Selection mode. No pixel fragments are produced, and no change to the
frame buffer contents is made. Instead, a record of the names of primitives that
would have been drawn if the render mode had been ?GL_RENDER is returned in a
select buffer, which must be created (see gl:selectBuffer/2 ) before selection mode
is entered.
?GL_FEEDBACK: Feedback mode. No pixel fragments are produced, and no change to the
frame buffer contents is made. Instead, the coordinates and attributes of vertices
that would have been drawn if the render mode had been ?GL_RENDER is returned in a
feedback buffer, which must be created (see gl:feedbackBuffer/3 ) before feedback
mode is entered.
The return value of gl:renderMode is determined by the render mode at the time
gl:renderMode is called, rather than by Mode . The values returned for the three
render modes are as follows:
?GL_RENDER: 0.
?GL_SELECT: The number of hit records transferred to the select buffer.
?GL_FEEDBACK: The number of values (not vertices) transferred to the feedback
buffer.
See the gl:selectBuffer/2 and gl:feedbackBuffer/3 reference pages for more details
concerning selection and feedback operation.
See external documentation.
getError() -> enum()
Return error information
gl:getError returns the value of the error flag. Each detectable error is assigned
a numeric code and symbolic name. When an error occurs, the error flag is set to
the appropriate error code value. No other errors are recorded until gl:getError is
called, the error code is returned, and the flag is reset to ?GL_NO_ERROR. If a
call to gl:getError returns ?GL_NO_ERROR, there has been no detectable error since
the last call to gl:getError , or since the GL was initialized.
To allow for distributed implementations, there may be several error flags. If any
single error flag has recorded an error, the value of that flag is returned and
that flag is reset to ?GL_NO_ERROR when gl:getError is called. If more than one
flag has recorded an error, gl:getError returns and clears an arbitrary error flag
value. Thus, gl:getError should always be called in a loop, until it returns
?GL_NO_ERROR , if all error flags are to be reset.
Initially, all error flags are set to ?GL_NO_ERROR.
The following errors are currently defined:
?GL_NO_ERROR: No error has been recorded. The value of this symbolic constant is
guaranteed to be 0.
?GL_INVALID_ENUM: An unacceptable value is specified for an enumerated argument.
The offending command is ignored and has no other side effect than to set the error
flag.
?GL_INVALID_VALUE: A numeric argument is out of range. The offending command is
ignored and has no other side effect than to set the error flag.
?GL_INVALID_OPERATION: The specified operation is not allowed in the current state.
The offending command is ignored and has no other side effect than to set the error
flag.
?GL_INVALID_FRAMEBUFFER_OPERATION: The framebuffer object is not complete. The
offending command is ignored and has no other side effect than to set the error
flag.
?GL_OUT_OF_MEMORY: There is not enough memory left to execute the command. The
state of the GL is undefined, except for the state of the error flags, after this
error is recorded.
When an error flag is set, results of a GL operation are undefined only if
?GL_OUT_OF_MEMORY has occurred. In all other cases, the command generating the
error is ignored and has no effect on the GL state or frame buffer contents. If the
generating command returns a value, it returns 0. If gl:getError itself generates
an error, it returns 0.
See external documentation.
getString(Name) -> string()
Types:
Name = enum()
Return a string describing the current GL connection
gl:getString returns a pointer to a static string describing some aspect of the
current GL connection. Name can be one of the following:
?GL_VENDOR: Returns the company responsible for this GL implementation. This name
does not change from release to release.
?GL_RENDERER: Returns the name of the renderer. This name is typically specific to
a particular configuration of a hardware platform. It does not change from release
to release.
?GL_VERSION: Returns a version or release number.
?GL_SHADING_LANGUAGE_VERSION: Returns a version or release number for the shading
language.
gl:getStringi returns a pointer to a static string indexed by Index . Name can be
one of the following:
?GL_EXTENSIONS: For gl:getStringi only, returns the extension string supported by
the implementation at Index .
Strings ?GL_VENDOR and ?GL_RENDERER together uniquely specify a platform. They do
not change from release to release and should be used by platform-recognition
algorithms.
The ?GL_VERSION and ?GL_SHADING_LANGUAGE_VERSION strings begin with a version
number. The version number uses one of these forms:
major_number.minor_numbermajor_number.minor_number.release_number
Vendor-specific information may follow the version number. Its format depends on
the implementation, but a space always separates the version number and the vendor-
specific information.
All strings are null-terminated.
See external documentation.
finish() -> ok
Block until all GL execution is complete
gl:finish does not return until the effects of all previously called GL commands
are complete. Such effects include all changes to GL state, all changes to
connection state, and all changes to the frame buffer contents.
See external documentation.
flush() -> ok
Force execution of GL commands in finite time
Different GL implementations buffer commands in several different locations,
including network buffers and the graphics accelerator itself. gl:flush empties all
of these buffers, causing all issued commands to be executed as quickly as they are
accepted by the actual rendering engine. Though this execution may not be completed
in any particular time period, it does complete in finite time.
Because any GL program might be executed over a network, or on an accelerator that
buffers commands, all programs should call gl:flush whenever they count on having
all of their previously issued commands completed. For example, call gl:flush
before waiting for user input that depends on the generated image.
See external documentation.
hint(Target, Mode) -> ok
Types:
Target = enum()
Mode = enum()
Specify implementation-specific hints
Certain aspects of GL behavior, when there is room for interpretation, can be
controlled with hints. A hint is specified with two arguments. Target is a symbolic
constant indicating the behavior to be controlled, and Mode is another symbolic
constant indicating the desired behavior. The initial value for each Target is
?GL_DONT_CARE . Mode can be one of the following:
?GL_FASTEST: The most efficient option should be chosen.
?GL_NICEST: The most correct, or highest quality, option should be chosen.
?GL_DONT_CARE: No preference.
Though the implementation aspects that can be hinted are well defined, the
interpretation of the hints depends on the implementation. The hint aspects that
can be specified with Target , along with suggested semantics, are as follows:
?GL_FRAGMENT_SHADER_DERIVATIVE_HINT: Indicates the accuracy of the derivative
calculation for the GL shading language fragment processing built-in functions:
?dFdx , ?dFdy, and ?fwidth.
?GL_LINE_SMOOTH_HINT: Indicates the sampling quality of antialiased lines. If a
larger filter function is applied, hinting ?GL_NICEST can result in more pixel
fragments being generated during rasterization.
?GL_POLYGON_SMOOTH_HINT: Indicates the sampling quality of antialiased polygons.
Hinting ?GL_NICEST can result in more pixel fragments being generated during
rasterization, if a larger filter function is applied.
?GL_TEXTURE_COMPRESSION_HINT: Indicates the quality and performance of the
compressing texture images. Hinting ?GL_FASTEST indicates that texture images
should be compressed as quickly as possible, while ?GL_NICEST indicates that
texture images should be compressed with as little image quality loss as possible.
?GL_NICEST should be selected if the texture is to be retrieved by
gl:getCompressedTexImage/3 for reuse.
See external documentation.
clearDepth(Depth) -> ok
Types:
Depth = clamp()
Specify the clear value for the depth buffer
gl:clearDepth specifies the depth value used by gl:clear/1 to clear the depth
buffer. Values specified by gl:clearDepth are clamped to the range [0 1].
See external documentation.
depthFunc(Func) -> ok
Types:
Func = enum()
Specify the value used for depth buffer comparisons
gl:depthFunc specifies the function used to compare each incoming pixel depth value
with the depth value present in the depth buffer. The comparison is performed only
if depth testing is enabled. (See gl:enable/1 and gl:enable/1 of ?GL_DEPTH_TEST .)
Func specifies the conditions under which the pixel will be drawn. The comparison
functions are as follows:
?GL_NEVER: Never passes.
?GL_LESS: Passes if the incoming depth value is less than the stored depth value.
?GL_EQUAL: Passes if the incoming depth value is equal to the stored depth value.
?GL_LEQUAL: Passes if the incoming depth value is less than or equal to the stored
depth value.
?GL_GREATER: Passes if the incoming depth value is greater than the stored depth
value.
?GL_NOTEQUAL: Passes if the incoming depth value is not equal to the stored depth
value.
?GL_GEQUAL: Passes if the incoming depth value is greater than or equal to the
stored depth value.
?GL_ALWAYS: Always passes.
The initial value of Func is ?GL_LESS. Initially, depth testing is disabled. If
depth testing is disabled or if no depth buffer exists, it is as if the depth test
always passes.
See external documentation.
depthMask(Flag) -> ok
Types:
Flag = 0 | 1
Enable or disable writing into the depth buffer
gl:depthMask specifies whether the depth buffer is enabled for writing. If Flag is
?GL_FALSE, depth buffer writing is disabled. Otherwise, it is enabled. Initially,
depth buffer writing is enabled.
See external documentation.
depthRange(Near_val, Far_val) -> ok
Types:
Near_val = clamp()
Far_val = clamp()
Specify mapping of depth values from normalized device coordinates to window
coordinates
After clipping and division by w, depth coordinates range from -1 to 1,
corresponding to the near and far clipping planes. gl:depthRange specifies a linear
mapping of the normalized depth coordinates in this range to window depth
coordinates. Regardless of the actual depth buffer implementation, window
coordinate depth values are treated as though they range from 0 through 1 (like
color components). Thus, the values accepted by gl:depthRange are both clamped to
this range before they are accepted.
The setting of (0,1) maps the near plane to 0 and the far plane to 1. With this
mapping, the depth buffer range is fully utilized.
See external documentation.
clearAccum(Red, Green, Blue, Alpha) -> ok
Types:
Red = float()
Green = float()
Blue = float()
Alpha = float()
Specify clear values for the accumulation buffer
gl:clearAccum specifies the red, green, blue, and alpha values used by gl:clear/1
to clear the accumulation buffer.
Values specified by gl:clearAccum are clamped to the range [-1 1].
See external documentation.
accum(Op, Value) -> ok
Types:
Op = enum()
Value = float()
Operate on the accumulation buffer
The accumulation buffer is an extended-range color buffer. Images are not rendered
into it. Rather, images rendered into one of the color buffers are added to the
contents of the accumulation buffer after rendering. Effects such as antialiasing
(of points, lines, and polygons), motion blur, and depth of field can be created by
accumulating images generated with different transformation matrices.
Each pixel in the accumulation buffer consists of red, green, blue, and alpha
values. The number of bits per component in the accumulation buffer depends on the
implementation. You can examine this number by calling gl:getBooleanv/1 four times,
with arguments ?GL_ACCUM_RED_BITS, ?GL_ACCUM_GREEN_BITS, ?GL_ACCUM_BLUE_BITS, and
?GL_ACCUM_ALPHA_BITS . Regardless of the number of bits per component, the range of
values stored by each component is [-1 1]. The accumulation buffer pixels are
mapped one-to-one with frame buffer pixels.
gl:accum operates on the accumulation buffer. The first argument, Op , is a
symbolic constant that selects an accumulation buffer operation. The second
argument, Value , is a floating-point value to be used in that operation. Five
operations are specified: ?GL_ACCUM , ?GL_LOAD, ?GL_ADD, ?GL_MULT, and ?GL_RETURN.
All accumulation buffer operations are limited to the area of the current scissor
box and applied identically to the red, green, blue, and alpha components of each
pixel. If a gl:accum operation results in a value outside the range [-1 1], the
contents of an accumulation buffer pixel component are undefined.
The operations are as follows:
?GL_ACCUM: Obtains R, G, B, and A values from the buffer currently selected for
reading (see gl:readBuffer/1 ). Each component value is divided by 2 n-1, where n
is the number of bits allocated to each color component in the currently selected
buffer. The result is a floating-point value in the range [0 1], which is
multiplied by Value and added to the corresponding pixel component in the
accumulation buffer, thereby updating the accumulation buffer.
?GL_LOAD: Similar to ?GL_ACCUM, except that the current value in the accumulation
buffer is not used in the calculation of the new value. That is, the R, G, B, and A
values from the currently selected buffer are divided by 2 n-1, multiplied by Value
, and then stored in the corresponding accumulation buffer cell, overwriting the
current value.
?GL_ADD: Adds Value to each R, G, B, and A in the accumulation buffer.
?GL_MULT: Multiplies each R, G, B, and A in the accumulation buffer by Value and
returns the scaled component to its corresponding accumulation buffer location.
?GL_RETURN: Transfers accumulation buffer values to the color buffer or buffers
currently selected for writing. Each R, G, B, and A component is multiplied by
Value , then multiplied by 2 n-1, clamped to the range [0 2 n-1], and stored in the
corresponding display buffer cell. The only fragment operations that are applied to
this transfer are pixel ownership, scissor, dithering, and color writemasks.
To clear the accumulation buffer, call gl:clearAccum/4 with R, G, B, and A values
to set it to, then call gl:clear/1 with the accumulation buffer enabled.
See external documentation.
matrixMode(Mode) -> ok
Types:
Mode = enum()
Specify which matrix is the current matrix
gl:matrixMode sets the current matrix mode. Mode can assume one of four values:
?GL_MODELVIEW: Applies subsequent matrix operations to the modelview matrix stack.
?GL_PROJECTION: Applies subsequent matrix operations to the projection matrix
stack.
?GL_TEXTURE: Applies subsequent matrix operations to the texture matrix stack.
?GL_COLOR: Applies subsequent matrix operations to the color matrix stack.
To find out which matrix stack is currently the target of all matrix operations,
call gl:getBooleanv/1 with argument ?GL_MATRIX_MODE. The initial value is
?GL_MODELVIEW.
See external documentation.
ortho(Left, Right, Bottom, Top, Near_val, Far_val) -> ok
Types:
Left = float()
Right = float()
Bottom = float()
Top = float()
Near_val = float()
Far_val = float()
Multiply the current matrix with an orthographic matrix
gl:ortho describes a transformation that produces a parallel projection. The
current matrix (see gl:matrixMode/1 ) is multiplied by this matrix and the result
replaces the current matrix, as if gl:multMatrixd/1 were called with the following
matrix as its argument:
((2/(right-left)) 0 0(t x) 0(2/(top-bottom)) 0(t y) 0 0(-2/(farVal-nearVal))(t z) 0
0 0 1)
where t x=-((right+left)/(right-left)) t y=-((top+bottom)/(top-bottom)) t
z=-((farVal+nearVal)/(farVal-nearVal))
Typically, the matrix mode is ?GL_PROJECTION, and (left bottom-nearVal) and (right
top-nearVal) specify the points on the near clipping plane that are mapped to the
lower left and upper right corners of the window, respectively, assuming that the
eye is located at (0, 0, 0). -farVal specifies the location of the far clipping
plane. Both NearVal and FarVal can be either positive or negative.
Use gl:pushMatrix/0 and gl:pushMatrix/0 to save and restore the current matrix
stack.
See external documentation.
frustum(Left, Right, Bottom, Top, Near_val, Far_val) -> ok
Types:
Left = float()
Right = float()
Bottom = float()
Top = float()
Near_val = float()
Far_val = float()
Multiply the current matrix by a perspective matrix
gl:frustum describes a perspective matrix that produces a perspective projection.
The current matrix (see gl:matrixMode/1 ) is multiplied by this matrix and the
result replaces the current matrix, as if gl:multMatrixd/1 were called with the
following matrix as its argument:
[((2 nearVal)/(right-left)) 0 A 0 0((2 nearVal)/(top-bottom)) B 0 0 0 C D 0 0 -1 0]
A=(right+left)/(right-left)
B=(top+bottom)/(top-bottom)
C=-((farVal+nearVal)/(farVal-nearVal))
D=-((2 farVal nearVal)/(farVal-nearVal))
Typically, the matrix mode is ?GL_PROJECTION, and (left bottom-nearVal) and (right
top-nearVal) specify the points on the near clipping plane that are mapped to the
lower left and upper right corners of the window, assuming that the eye is located
at (0, 0, 0). -farVal specifies the location of the far clipping plane. Both
NearVal and FarVal must be positive.
Use gl:pushMatrix/0 and gl:pushMatrix/0 to save and restore the current matrix
stack.
See external documentation.
viewport(X, Y, Width, Height) -> ok
Types:
X = integer()
Y = integer()
Width = integer()
Height = integer()
Set the viewport
gl:viewport specifies the affine transformation of x and y from normalized device
coordinates to window coordinates. Let (x nd y nd) be normalized device
coordinates. Then the window coordinates (x w y w) are computed as follows:
x w=(x nd+1) (width/2)+x
y w=(y nd+1) (height/2)+y
Viewport width and height are silently clamped to a range that depends on the
implementation. To query this range, call gl:getBooleanv/1 with argument
?GL_MAX_VIEWPORT_DIMS.
See external documentation.
pushMatrix() -> ok
Push and pop the current matrix stack
There is a stack of matrices for each of the matrix modes. In ?GL_MODELVIEW mode,
the stack depth is at least 32. In the other modes, ?GL_COLOR, ?GL_PROJECTION , and
?GL_TEXTURE, the depth is at least 2. The current matrix in any mode is the matrix
on the top of the stack for that mode.
gl:pushMatrix pushes the current matrix stack down by one, duplicating the current
matrix. That is, after a gl:pushMatrix call, the matrix on top of the stack is
identical to the one below it.
gl:pushMatrix/0 pops the current matrix stack, replacing the current matrix with
the one below it on the stack.
Initially, each of the stacks contains one matrix, an identity matrix.
It is an error to push a full matrix stack or to pop a matrix stack that contains
only a single matrix. In either case, the error flag is set and no other change is
made to GL state.
See external documentation.
popMatrix() -> ok
See pushMatrix/0
loadIdentity() -> ok
Replace the current matrix with the identity matrix
gl:loadIdentity replaces the current matrix with the identity matrix. It is
semantically equivalent to calling gl:loadMatrixd/1 with the identity matrix
((1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1))
but in some cases it is more efficient.
See external documentation.
loadMatrixd(M) -> ok
Types:
M = matrix()
Replace the current matrix with the specified matrix
gl:loadMatrix replaces the current matrix with the one whose elements are specified
by M . The current matrix is the projection matrix, modelview matrix, or texture
matrix, depending on the current matrix mode (see gl:matrixMode/1 ).
The current matrix, M, defines a transformation of coordinates. For instance,
assume M refers to the modelview matrix. If v=(v[0] v[1] v[2] v[3]) is the set of
object coordinates of a vertex, and M points to an array of 16 single- or double-
precision floating-point values m={m[0] m[1] ... m[15]}, then the modelview
transformation M(v) does the following:
M(v)=(m[0] m[4] m[8] m[12] m[1] m[5] m[9] m[13] m[2] m[6] m[10] m[14] m[3] m[7]
m[11] m[15])×(v[0] v[1] v[2] v[3])
Projection and texture transformations are similarly defined.
See external documentation.
loadMatrixf(M) -> ok
Types:
M = matrix()
See loadMatrixd/1
multMatrixd(M) -> ok
Types:
M = matrix()
Multiply the current matrix with the specified matrix
gl:multMatrix multiplies the current matrix with the one specified using M , and
replaces the current matrix with the product.
The current matrix is determined by the current matrix mode (see gl:matrixMode/1 ).
It is either the projection matrix, modelview matrix, or the texture matrix.
See external documentation.
multMatrixf(M) -> ok
Types:
M = matrix()
See multMatrixd/1
rotated(Angle, X, Y, Z) -> ok
Types:
Angle = float()
X = float()
Y = float()
Z = float()
Multiply the current matrix by a rotation matrix
gl:rotate produces a rotation of Angle degrees around the vector (x y z). The
current matrix (see gl:matrixMode/1 ) is multiplied by a rotation matrix with the
product replacing the current matrix, as if gl:multMatrixd/1 were called with the
following matrix as its argument:
(x 2(1-c)+c x y(1-c)-z s x z(1-c)+y s 0 y x(1-c)+z s y 2(1-c)+c y z(1-c)-x s 0 x
z(1-c)-y s y z(1-c)+x s z 2(1-c)+c 0 0 0 0 1)
Where c=cos(angle), s=sin(angle), and ||(x y z)||=1 (if not, the GL will normalize
this vector).
If the matrix mode is either ?GL_MODELVIEW or ?GL_PROJECTION, all objects drawn
after gl:rotate is called are rotated. Use gl:pushMatrix/0 and gl:pushMatrix/0 to
save and restore the unrotated coordinate system.
See external documentation.
rotatef(Angle, X, Y, Z) -> ok
Types:
Angle = float()
X = float()
Y = float()
Z = float()
See rotated/4
scaled(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
Multiply the current matrix by a general scaling matrix
gl:scale produces a nonuniform scaling along the x, y, and z axes. The three
parameters indicate the desired scale factor along each of the three axes.
The current matrix (see gl:matrixMode/1 ) is multiplied by this scale matrix, and
the product replaces the current matrix as if gl:multMatrixd/1 were called with the
following matrix as its argument:
(x 0 0 0 0 y 0 0 0 0 z 0 0 0 0 1)
If the matrix mode is either ?GL_MODELVIEW or ?GL_PROJECTION, all objects drawn
after gl:scale is called are scaled.
Use gl:pushMatrix/0 and gl:pushMatrix/0 to save and restore the unscaled coordinate
system.
See external documentation.
scalef(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See scaled/3
translated(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
Multiply the current matrix by a translation matrix
gl:translate produces a translation by (x y z). The current matrix (see
gl:matrixMode/1 ) is multiplied by this translation matrix, with the product
replacing the current matrix, as if gl:multMatrixd/1 were called with the following
matrix for its argument:
(1 0 0 x 0 1 0 y 0 0 1 z 0 0 0 1)
If the matrix mode is either ?GL_MODELVIEW or ?GL_PROJECTION, all objects drawn
after a call to gl:translate are translated.
Use gl:pushMatrix/0 and gl:pushMatrix/0 to save and restore the untranslated
coordinate system.
See external documentation.
translatef(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See translated/3
isList(List) -> 0 | 1
Types:
List = integer()
Determine if a name corresponds to a display list
gl:isList returns ?GL_TRUE if List is the name of a display list and returns
?GL_FALSE if it is not, or if an error occurs.
A name returned by gl:genLists/1 , but not yet associated with a display list by
calling gl:newList/2 , is not the name of a display list.
See external documentation.
deleteLists(List, Range) -> ok
Types:
List = integer()
Range = integer()
Delete a contiguous group of display lists
gl:deleteLists causes a contiguous group of display lists to be deleted. List is
the name of the first display list to be deleted, and Range is the number of
display lists to delete. All display lists d with list<= d<= list+range-1 are
deleted.
All storage locations allocated to the specified display lists are freed, and the
names are available for reuse at a later time. Names within the range that do not
have an associated display list are ignored. If Range is 0, nothing happens.
See external documentation.
genLists(Range) -> integer()
Types:
Range = integer()
Generate a contiguous set of empty display lists
gl:genLists has one argument, Range . It returns an integer n such that Range
contiguous empty display lists, named n, n+1, ..., n+range-1, are created. If Range
is 0, if there is no group of Range contiguous names available, or if any error is
generated, no display lists are generated, and 0 is returned.
See external documentation.
newList(List, Mode) -> ok
Types:
List = integer()
Mode = enum()
Create or replace a display list
Display lists are groups of GL commands that have been stored for subsequent
execution. Display lists are created with gl:newList. All subsequent commands are
placed in the display list, in the order issued, until gl:endList/0 is called.
gl:newList has two arguments. The first argument, List , is a positive integer that
becomes the unique name for the display list. Names can be created and reserved
with gl:genLists/1 and tested for uniqueness with gl:isList/1 . The second
argument, Mode , is a symbolic constant that can assume one of two values:
?GL_COMPILE: Commands are merely compiled.
?GL_COMPILE_AND_EXECUTE: Commands are executed as they are compiled into the
display list.
Certain commands are not compiled into the display list but are executed
immediately, regardless of the display-list mode. These commands are
gl:areTexturesResident/1 , gl:colorPointer/4 , gl:deleteLists/2 ,
gl:deleteTextures/1 , gl:enableClientState/1 , gl:edgeFlagPointer/2 ,
gl:enableClientState/1 , gl:feedbackBuffer/3 , gl:finish/0 , gl:flush/0 ,
gl:genLists/1 , gl:genTextures/1 , gl:indexPointer/3 , gl:interleavedArrays/3 ,
gl:isEnabled/1 , gl:isList/1 , gl:isTexture/1 , gl:normalPointer/3 ,
gl:pushClientAttrib/1 , gl:pixelStoref/2 , gl:pushClientAttrib/1 , gl:readPixels/7
, gl:renderMode/1 , gl:selectBuffer/2 , gl:texCoordPointer/4 , gl:vertexPointer/4 ,
and all of the gl:getBooleanv/1 commands.
Similarly, gl:texImage1D/8 , gl:texImage2D/9 , and gl:texImage3D/10 are executed
immediately and not compiled into the display list when their first argument is
?GL_PROXY_TEXTURE_1D, ?GL_PROXY_TEXTURE_1D, or ?GL_PROXY_TEXTURE_3D , respectively.
When the ARB_imaging extension is supported, gl:histogram/4 executes immediately
when its argument is ?GL_PROXY_HISTOGRAM. Similarly, gl:colorTable/6 executes
immediately when its first argument is ?GL_PROXY_COLOR_TABLE,
?GL_PROXY_POST_CONVOLUTION_COLOR_TABLE , or
?GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE.
For OpenGL versions 1.3 and greater, or when the ARB_multitexture extension is
supported, gl:clientActiveTexture/1 is not compiled into display lists, but
executed immediately.
When gl:endList/0 is encountered, the display-list definition is completed by
associating the list with the unique name List (specified in the gl:newList
command). If a display list with name List already exists, it is replaced only when
gl:endList/0 is called.
See external documentation.
endList() -> ok
glBeginList
See external documentation.
callList(List) -> ok
Types:
List = integer()
Execute a display list
gl:callList causes the named display list to be executed. The commands saved in the
display list are executed in order, just as if they were called without using a
display list. If List has not been defined as a display list, gl:callList is
ignored.
gl:callList can appear inside a display list. To avoid the possibility of infinite
recursion resulting from display lists calling one another, a limit is placed on
the nesting level of display lists during display-list execution. This limit is at
least 64, and it depends on the implementation.
GL state is not saved and restored across a call to gl:callList. Thus, changes made
to GL state during the execution of a display list remain after execution of the
display list is completed. Use gl:pushAttrib/1 , gl:pushAttrib/1 , gl:pushMatrix/0
, and gl:pushMatrix/0 to preserve GL state across gl:callList calls.
See external documentation.
callLists(Lists) -> ok
Types:
Lists = [integer()]
Execute a list of display lists
gl:callLists causes each display list in the list of names passed as Lists to be
executed. As a result, the commands saved in each display list are executed in
order, just as if they were called without using a display list. Names of display
lists that have not been defined are ignored.
gl:callLists provides an efficient means for executing more than one display list.
Type allows lists with various name formats to be accepted. The formats are as
follows:
?GL_BYTE: Lists is treated as an array of signed bytes, each in the range -128
through 127.
?GL_UNSIGNED_BYTE: Lists is treated as an array of unsigned bytes, each in the
range 0 through 255.
?GL_SHORT: Lists is treated as an array of signed two-byte integers, each in the
range -32768 through 32767.
?GL_UNSIGNED_SHORT: Lists is treated as an array of unsigned two-byte integers,
each in the range 0 through 65535.
?GL_INT: Lists is treated as an array of signed four-byte integers.
?GL_UNSIGNED_INT: Lists is treated as an array of unsigned four-byte integers.
?GL_FLOAT: Lists is treated as an array of four-byte floating-point values.
?GL_2_BYTES: Lists is treated as an array of unsigned bytes. Each pair of bytes
specifies a single display-list name. The value of the pair is computed as 256
times the unsigned value of the first byte plus the unsigned value of the second
byte.
?GL_3_BYTES: Lists is treated as an array of unsigned bytes. Each triplet of bytes
specifies a single display-list name. The value of the triplet is computed as 65536
times the unsigned value of the first byte, plus 256 times the unsigned value of
the second byte, plus the unsigned value of the third byte.
?GL_4_BYTES: Lists is treated as an array of unsigned bytes. Each quadruplet of
bytes specifies a single display-list name. The value of the quadruplet is computed
as 16777216 times the unsigned value of the first byte, plus 65536 times the
unsigned value of the second byte, plus 256 times the unsigned value of the third
byte, plus the unsigned value of the fourth byte.
The list of display-list names is not null-terminated. Rather, N specifies how many
names are to be taken from Lists .
An additional level of indirection is made available with the gl:listBase/1
command, which specifies an unsigned offset that is added to each display-list name
specified in Lists before that display list is executed.
gl:callLists can appear inside a display list. To avoid the possibility of infinite
recursion resulting from display lists calling one another, a limit is placed on
the nesting level of display lists during display-list execution. This limit must
be at least 64, and it depends on the implementation.
GL state is not saved and restored across a call to gl:callLists. Thus, changes
made to GL state during the execution of the display lists remain after execution
is completed. Use gl:pushAttrib/1 , gl:pushAttrib/1 , gl:pushMatrix/0 , and
gl:pushMatrix/0 to preserve GL state across gl:callLists calls.
See external documentation.
listBase(Base) -> ok
Types:
Base = integer()
set the display-list base for
gl:callLists/1
gl:callLists/1 specifies an array of offsets. Display-list names are generated by
adding Base to each offset. Names that reference valid display lists are executed;
the others are ignored.
See external documentation.
begin(Mode) -> ok
Types:
Mode = enum()
Delimit the vertices of a primitive or a group of like primitives
gl:'begin' and gl:'begin'/1 delimit the vertices that define a primitive or a group
of like primitives. gl:'begin' accepts a single argument that specifies in which of
ten ways the vertices are interpreted. Taking n as an integer count starting at
one, and N as the total number of vertices specified, the interpretations are as
follows:
?GL_POINTS: Treats each vertex as a single point. Vertex n defines point n. N
points are drawn.
?GL_LINES: Treats each pair of vertices as an independent line segment. Vertices 2
n-1 and 2 n define line n. N/2 lines are drawn.
?GL_LINE_STRIP: Draws a connected group of line segments from the first vertex to
the last. Vertices n and n+1 define line n. N-1 lines are drawn.
?GL_LINE_LOOP: Draws a connected group of line segments from the first vertex to
the last, then back to the first. Vertices n and n+1 define line n. The last line,
however, is defined by vertices N and 1. N lines are drawn.
?GL_TRIANGLES: Treats each triplet of vertices as an independent triangle. Vertices
3 n-2, 3 n-1, and 3 n define triangle n. N/3 triangles are drawn.
?GL_TRIANGLE_STRIP: Draws a connected group of triangles. One triangle is defined
for each vertex presented after the first two vertices. For odd n, vertices n, n+1,
and n+2 define triangle n. For even n, vertices n+1, n, and n+2 define triangle n.
N-2 triangles are drawn.
?GL_TRIANGLE_FAN: Draws a connected group of triangles. One triangle is defined for
each vertex presented after the first two vertices. Vertices 1, n+1, and n+2 define
triangle n. N-2 triangles are drawn.
?GL_QUADS: Treats each group of four vertices as an independent quadrilateral.
Vertices 4 n-3, 4 n-2, 4 n-1, and 4 n define quadrilateral n. N/4 quadrilaterals
are drawn.
?GL_QUAD_STRIP: Draws a connected group of quadrilaterals. One quadrilateral is
defined for each pair of vertices presented after the first pair. Vertices 2 n-1, 2
n, 2 n+2, and 2 n+1 define quadrilateral n. N/2-1 quadrilaterals are drawn. Note
that the order in which vertices are used to construct a quadrilateral from strip
data is different from that used with independent data.
?GL_POLYGON: Draws a single, convex polygon. Vertices 1 through N define this
polygon.
Only a subset of GL commands can be used between gl:'begin' and gl:'begin'/1 . The
commands are gl:vertex2d/2 , gl:color3b/3 , gl:secondaryColor3b/3 , gl:indexd/1 ,
gl:normal3b/3 , gl:fogCoordf/1 , gl:texCoord1d/1 , gl:multiTexCoord1d/2 ,
gl:vertexAttrib1d/2 , gl:evalCoord1d/1 , gl:evalPoint1/1 , gl:arrayElement/1 ,
gl:materialf/3 , and gl:edgeFlag/1 . Also, it is acceptable to use gl:callList/1 or
gl:callLists/1 to execute display lists that include only the preceding commands.
If any other GL command is executed between gl:'begin' and gl:'begin'/1 , the error
flag is set and the command is ignored.
Regardless of the value chosen for Mode , there is no limit to the number of
vertices that can be defined between gl:'begin' and gl:'begin'/1 . Lines,
triangles, quadrilaterals, and polygons that are incompletely specified are not
drawn. Incomplete specification results when either too few vertices are provided
to specify even a single primitive or when an incorrect multiple of vertices is
specified. The incomplete primitive is ignored; the rest are drawn.
The minimum specification of vertices for each primitive is as follows: 1 for a
point, 2 for a line, 3 for a triangle, 4 for a quadrilateral, and 3 for a polygon.
Modes that require a certain multiple of vertices are ?GL_LINES (2), ?GL_TRIANGLES
(3), ?GL_QUADS (4), and ?GL_QUAD_STRIP (2).
See external documentation.
end() -> ok
See 'begin'/1
vertex2d(X, Y) -> ok
Types:
X = float()
Y = float()
Specify a vertex
gl:vertex commands are used within gl:'begin'/1 / gl:'begin'/1 pairs to specify
point, line, and polygon vertices. The current color, normal, texture coordinates,
and fog coordinate are associated with the vertex when gl:vertex is called.
When only x and y are specified, z defaults to 0 and w defaults to 1. When x, y,
and z are specified, w defaults to 1.
See external documentation.
vertex2f(X, Y) -> ok
Types:
X = float()
Y = float()
See vertex2d/2
vertex2i(X, Y) -> ok
Types:
X = integer()
Y = integer()
See vertex2d/2
vertex2s(X, Y) -> ok
Types:
X = integer()
Y = integer()
See vertex2d/2
vertex3d(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See vertex2d/2
vertex3f(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See vertex2d/2
vertex3i(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See vertex2d/2
vertex3s(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See vertex2d/2
vertex4d(X, Y, Z, W) -> ok
Types:
X = float()
Y = float()
Z = float()
W = float()
See vertex2d/2
vertex4f(X, Y, Z, W) -> ok
Types:
X = float()
Y = float()
Z = float()
W = float()
See vertex2d/2
vertex4i(X, Y, Z, W) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertex2d/2
vertex4s(X, Y, Z, W) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertex2d/2
vertex2dv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to vertex2d(X, Y).
vertex2fv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to vertex2f(X, Y).
vertex2iv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to vertex2i(X, Y).
vertex2sv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to vertex2s(X, Y).
vertex3dv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to vertex3d(X, Y, Z).
vertex3fv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to vertex3f(X, Y, Z).
vertex3iv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to vertex3i(X, Y, Z).
vertex3sv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to vertex3s(X, Y, Z).
vertex4dv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to vertex4d(X, Y, Z, W).
vertex4fv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to vertex4f(X, Y, Z, W).
vertex4iv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertex4i(X, Y, Z, W).
vertex4sv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertex4s(X, Y, Z, W).
normal3b(Nx, Ny, Nz) -> ok
Types:
Nx = integer()
Ny = integer()
Nz = integer()
Set the current normal vector
The current normal is set to the given coordinates whenever gl:normal is issued.
Byte, short, or integer arguments are converted to floating-point format with a
linear mapping that maps the most positive representable integer value to 1.0 and
the most negative representable integer value to -1.0.
Normals specified with gl:normal need not have unit length. If ?GL_NORMALIZE is
enabled, then normals of any length specified with gl:normal are normalized after
transformation. If ?GL_RESCALE_NORMAL is enabled, normals are scaled by a scaling
factor derived from the modelview matrix. ?GL_RESCALE_NORMAL requires that the
originally specified normals were of unit length, and that the modelview matrix
contain only uniform scales for proper results. To enable and disable
normalization, call gl:enable/1 and gl:enable/1 with either ?GL_NORMALIZE or
?GL_RESCALE_NORMAL. Normalization is initially disabled.
See external documentation.
normal3d(Nx, Ny, Nz) -> ok
Types:
Nx = float()
Ny = float()
Nz = float()
See normal3b/3
normal3f(Nx, Ny, Nz) -> ok
Types:
Nx = float()
Ny = float()
Nz = float()
See normal3b/3
normal3i(Nx, Ny, Nz) -> ok
Types:
Nx = integer()
Ny = integer()
Nz = integer()
See normal3b/3
normal3s(Nx, Ny, Nz) -> ok
Types:
Nx = integer()
Ny = integer()
Nz = integer()
See normal3b/3
normal3bv(V) -> ok
Types:
V = {Nx::integer(), Ny::integer(), Nz::integer()}
Equivalent to normal3b(Nx, Ny, Nz).
normal3dv(V) -> ok
Types:
V = {Nx::float(), Ny::float(), Nz::float()}
Equivalent to normal3d(Nx, Ny, Nz).
normal3fv(V) -> ok
Types:
V = {Nx::float(), Ny::float(), Nz::float()}
Equivalent to normal3f(Nx, Ny, Nz).
normal3iv(V) -> ok
Types:
V = {Nx::integer(), Ny::integer(), Nz::integer()}
Equivalent to normal3i(Nx, Ny, Nz).
normal3sv(V) -> ok
Types:
V = {Nx::integer(), Ny::integer(), Nz::integer()}
Equivalent to normal3s(Nx, Ny, Nz).
indexd(C) -> ok
Types:
C = float()
Set the current color index
gl:index updates the current (single-valued) color index. It takes one argument,
the new value for the current color index.
The current index is stored as a floating-point value. Integer values are converted
directly to floating-point values, with no special mapping. The initial value is 1.
Index values outside the representable range of the color index buffer are not
clamped. However, before an index is dithered (if enabled) and written to the frame
buffer, it is converted to fixed-point format. Any bits in the integer portion of
the resulting fixed-point value that do not correspond to bits in the frame buffer
are masked out.
See external documentation.
indexf(C) -> ok
Types:
C = float()
See indexd/1
indexi(C) -> ok
Types:
C = integer()
See indexd/1
indexs(C) -> ok
Types:
C = integer()
See indexd/1
indexub(C) -> ok
Types:
C = integer()
See indexd/1
indexdv(C) -> ok
Types:
C = {C::float()}
Equivalent to indexd(C).
indexfv(C) -> ok
Types:
C = {C::float()}
Equivalent to indexf(C).
indexiv(C) -> ok
Types:
C = {C::integer()}
Equivalent to indexi(C).
indexsv(C) -> ok
Types:
C = {C::integer()}
Equivalent to indexs(C).
indexubv(C) -> ok
Types:
C = {C::integer()}
Equivalent to indexub(C).
color3b(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Set the current color
The GL stores both a current single-valued color index and a current four-valued
RGBA color. gl:color sets a new four-valued RGBA color. gl:color has two major
variants: gl:color3 and gl:color4. gl:color3 variants specify new red, green, and
blue values explicitly and set the current alpha value to 1.0 (full intensity)
implicitly. gl:color4 variants specify all four color components explicitly.
gl:color3b, gl:color4b, gl:color3s, gl:color4s, gl:color3i, and gl:color4i take
three or four signed byte, short, or long integers as arguments. When v is appended
to the name, the color commands can take a pointer to an array of such values.
Current color values are stored in floating-point format, with unspecified mantissa
and exponent sizes. Unsigned integer color components, when specified, are linearly
mapped to floating-point values such that the largest representable value maps to
1.0 (full intensity), and 0 maps to 0.0 (zero intensity). Signed integer color
components, when specified, are linearly mapped to floating-point values such that
the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. (Note that this mapping does not convert 0
precisely to 0.0.) Floating-point values are mapped directly.
Neither floating-point nor signed integer values are clamped to the range [0 1]
before the current color is updated. However, color components are clamped to this
range before they are interpolated or written into a color buffer.
See external documentation.
color3d(Red, Green, Blue) -> ok
Types:
Red = float()
Green = float()
Blue = float()
See color3b/3
color3f(Red, Green, Blue) -> ok
Types:
Red = float()
Green = float()
Blue = float()
See color3b/3
color3i(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See color3b/3
color3s(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See color3b/3
color3ub(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See color3b/3
color3ui(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See color3b/3
color3us(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See color3b/3
color4b(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color4d(Red, Green, Blue, Alpha) -> ok
Types:
Red = float()
Green = float()
Blue = float()
Alpha = float()
See color3b/3
color4f(Red, Green, Blue, Alpha) -> ok
Types:
Red = float()
Green = float()
Blue = float()
Alpha = float()
See color3b/3
color4i(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color4s(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color4ub(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color4ui(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color4us(Red, Green, Blue, Alpha) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Alpha = integer()
See color3b/3
color3bv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3b(Red, Green, Blue).
color3dv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float()}
Equivalent to color3d(Red, Green, Blue).
color3fv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float()}
Equivalent to color3f(Red, Green, Blue).
color3iv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3i(Red, Green, Blue).
color3sv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3s(Red, Green, Blue).
color3ubv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3ub(Red, Green, Blue).
color3uiv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3ui(Red, Green, Blue).
color3usv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to color3us(Red, Green, Blue).
color4bv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4b(Red, Green, Blue, Alpha).
color4dv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float(), Alpha::float()}
Equivalent to color4d(Red, Green, Blue, Alpha).
color4fv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float(), Alpha::float()}
Equivalent to color4f(Red, Green, Blue, Alpha).
color4iv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4i(Red, Green, Blue, Alpha).
color4sv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4s(Red, Green, Blue, Alpha).
color4ubv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4ub(Red, Green, Blue, Alpha).
color4uiv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4ui(Red, Green, Blue, Alpha).
color4usv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer(), Alpha::integer()}
Equivalent to color4us(Red, Green, Blue, Alpha).
texCoord1d(S) -> ok
Types:
S = float()
Set the current texture coordinates
gl:texCoord specifies texture coordinates in one, two, three, or four dimensions.
gl:texCoord1 sets the current texture coordinates to (s 0 0 1); a call to
gl:texCoord2 sets them to (s t 0 1). Similarly, gl:texCoord3 specifies the texture
coordinates as (s t r 1), and gl:texCoord4 defines all four components explicitly
as (s t r q).
The current texture coordinates are part of the data that is associated with each
vertex and with the current raster position. Initially, the values for s, t, r ,
and q are (0, 0, 0, 1).
See external documentation.
texCoord1f(S) -> ok
Types:
S = float()
See texCoord1d/1
texCoord1i(S) -> ok
Types:
S = integer()
See texCoord1d/1
texCoord1s(S) -> ok
Types:
S = integer()
See texCoord1d/1
texCoord2d(S, T) -> ok
Types:
S = float()
T = float()
See texCoord1d/1
texCoord2f(S, T) -> ok
Types:
S = float()
T = float()
See texCoord1d/1
texCoord2i(S, T) -> ok
Types:
S = integer()
T = integer()
See texCoord1d/1
texCoord2s(S, T) -> ok
Types:
S = integer()
T = integer()
See texCoord1d/1
texCoord3d(S, T, R) -> ok
Types:
S = float()
T = float()
R = float()
See texCoord1d/1
texCoord3f(S, T, R) -> ok
Types:
S = float()
T = float()
R = float()
See texCoord1d/1
texCoord3i(S, T, R) -> ok
Types:
S = integer()
T = integer()
R = integer()
See texCoord1d/1
texCoord3s(S, T, R) -> ok
Types:
S = integer()
T = integer()
R = integer()
See texCoord1d/1
texCoord4d(S, T, R, Q) -> ok
Types:
S = float()
T = float()
R = float()
Q = float()
See texCoord1d/1
texCoord4f(S, T, R, Q) -> ok
Types:
S = float()
T = float()
R = float()
Q = float()
See texCoord1d/1
texCoord4i(S, T, R, Q) -> ok
Types:
S = integer()
T = integer()
R = integer()
Q = integer()
See texCoord1d/1
texCoord4s(S, T, R, Q) -> ok
Types:
S = integer()
T = integer()
R = integer()
Q = integer()
See texCoord1d/1
texCoord1dv(V) -> ok
Types:
V = {S::float()}
Equivalent to texCoord1d(S).
texCoord1fv(V) -> ok
Types:
V = {S::float()}
Equivalent to texCoord1f(S).
texCoord1iv(V) -> ok
Types:
V = {S::integer()}
Equivalent to texCoord1i(S).
texCoord1sv(V) -> ok
Types:
V = {S::integer()}
Equivalent to texCoord1s(S).
texCoord2dv(V) -> ok
Types:
V = {S::float(), T::float()}
Equivalent to texCoord2d(S, T).
texCoord2fv(V) -> ok
Types:
V = {S::float(), T::float()}
Equivalent to texCoord2f(S, T).
texCoord2iv(V) -> ok
Types:
V = {S::integer(), T::integer()}
Equivalent to texCoord2i(S, T).
texCoord2sv(V) -> ok
Types:
V = {S::integer(), T::integer()}
Equivalent to texCoord2s(S, T).
texCoord3dv(V) -> ok
Types:
V = {S::float(), T::float(), R::float()}
Equivalent to texCoord3d(S, T, R).
texCoord3fv(V) -> ok
Types:
V = {S::float(), T::float(), R::float()}
Equivalent to texCoord3f(S, T, R).
texCoord3iv(V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer()}
Equivalent to texCoord3i(S, T, R).
texCoord3sv(V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer()}
Equivalent to texCoord3s(S, T, R).
texCoord4dv(V) -> ok
Types:
V = {S::float(), T::float(), R::float(), Q::float()}
Equivalent to texCoord4d(S, T, R, Q).
texCoord4fv(V) -> ok
Types:
V = {S::float(), T::float(), R::float(), Q::float()}
Equivalent to texCoord4f(S, T, R, Q).
texCoord4iv(V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer(), Q::integer()}
Equivalent to texCoord4i(S, T, R, Q).
texCoord4sv(V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer(), Q::integer()}
Equivalent to texCoord4s(S, T, R, Q).
rasterPos2d(X, Y) -> ok
Types:
X = float()
Y = float()
Specify the raster position for pixel operations
The GL maintains a 3D position in window coordinates. This position, called the
raster position, is used to position pixel and bitmap write operations. It is
maintained with subpixel accuracy. See gl:bitmap/7 , gl:drawPixels/5 , and
gl:copyPixels/5 .
The current raster position consists of three window coordinates ( x, y, z), a clip
coordinate value ( w), an eye coordinate distance, a valid bit, and associated
color data and texture coordinates. The w coordinate is a clip coordinate, because
w is not projected to window coordinates. gl:rasterPos4 specifies object
coordinates x, y, z, and w explicitly. gl:rasterPos3 specifies object coordinate x,
y, and z explicitly, while w is implicitly set to 1. gl:rasterPos2 uses the
argument values for x and y while implicitly setting z and w to 0 and 1.
The object coordinates presented by gl:rasterPos are treated just like those of a
gl:vertex2d/2 command: They are transformed by the current modelview and projection
matrices and passed to the clipping stage. If the vertex is not culled, then it is
projected and scaled to window coordinates, which become the new current raster
position, and the ?GL_CURRENT_RASTER_POSITION_VALID flag is set. If the vertex is
culled, then the valid bit is cleared and the current raster position and
associated color and texture coordinates are undefined.
The current raster position also includes some associated color data and texture
coordinates. If lighting is enabled, then ?GL_CURRENT_RASTER_COLOR (in RGBA mode)
or ?GL_CURRENT_RASTER_INDEX (in color index mode) is set to the color produced by
the lighting calculation (see gl:lightf/3 , gl:lightModelf/2 , and gl:shadeModel/1
). If lighting is disabled, current color (in RGBA mode, state variable
?GL_CURRENT_COLOR) or color index (in color index mode, state variable
?GL_CURRENT_INDEX) is used to update the current raster color.
?GL_CURRENT_RASTER_SECONDARY_COLOR (in RGBA mode) is likewise updated.
Likewise, ?GL_CURRENT_RASTER_TEXTURE_COORDS is updated as a function of
?GL_CURRENT_TEXTURE_COORDS , based on the texture matrix and the texture generation
functions (see gl:texGend/3 ). Finally, the distance from the origin of the eye
coordinate system to the vertex as transformed by only the modelview matrix
replaces ?GL_CURRENT_RASTER_DISTANCE.
Initially, the current raster position is (0, 0, 0, 1), the current raster distance
is 0, the valid bit is set, the associated RGBA color is (1, 1, 1, 1), the
associated color index is 1, and the associated texture coordinates are (0, 0, 0,
1). In RGBA mode, ?GL_CURRENT_RASTER_INDEX is always 1; in color index mode, the
current raster RGBA color always maintains its initial value.
See external documentation.
rasterPos2f(X, Y) -> ok
Types:
X = float()
Y = float()
See rasterPos2d/2
rasterPos2i(X, Y) -> ok
Types:
X = integer()
Y = integer()
See rasterPos2d/2
rasterPos2s(X, Y) -> ok
Types:
X = integer()
Y = integer()
See rasterPos2d/2
rasterPos3d(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See rasterPos2d/2
rasterPos3f(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See rasterPos2d/2
rasterPos3i(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See rasterPos2d/2
rasterPos3s(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See rasterPos2d/2
rasterPos4d(X, Y, Z, W) -> ok
Types:
X = float()
Y = float()
Z = float()
W = float()
See rasterPos2d/2
rasterPos4f(X, Y, Z, W) -> ok
Types:
X = float()
Y = float()
Z = float()
W = float()
See rasterPos2d/2
rasterPos4i(X, Y, Z, W) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
W = integer()
See rasterPos2d/2
rasterPos4s(X, Y, Z, W) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
W = integer()
See rasterPos2d/2
rasterPos2dv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to rasterPos2d(X, Y).
rasterPos2fv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to rasterPos2f(X, Y).
rasterPos2iv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to rasterPos2i(X, Y).
rasterPos2sv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to rasterPos2s(X, Y).
rasterPos3dv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to rasterPos3d(X, Y, Z).
rasterPos3fv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to rasterPos3f(X, Y, Z).
rasterPos3iv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to rasterPos3i(X, Y, Z).
rasterPos3sv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to rasterPos3s(X, Y, Z).
rasterPos4dv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to rasterPos4d(X, Y, Z, W).
rasterPos4fv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to rasterPos4f(X, Y, Z, W).
rasterPos4iv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to rasterPos4i(X, Y, Z, W).
rasterPos4sv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to rasterPos4s(X, Y, Z, W).
rectd(X1, Y1, X2, Y2) -> ok
Types:
X1 = float()
Y1 = float()
X2 = float()
Y2 = float()
Draw a rectangle
gl:rect supports efficient specification of rectangles as two corner points. Each
rectangle command takes four arguments, organized either as two consecutive pairs
of (x y) coordinates or as two pointers to arrays, each containing an (x y) pair.
The resulting rectangle is defined in the z=0 plane.
gl:rect( X1 , Y1 , X2 , Y2 ) is exactly equivalent to the following sequence:
glBegin(?GL_POLYGON); glVertex2( X1 , Y1 ); glVertex2( X2 , Y1 ); glVertex2( X2 ,
Y2 ); glVertex2( X1 , Y2 ); glEnd(); Note that if the second vertex is above and to
the right of the first vertex, the rectangle is constructed with a counterclockwise
winding.
See external documentation.
rectf(X1, Y1, X2, Y2) -> ok
Types:
X1 = float()
Y1 = float()
X2 = float()
Y2 = float()
See rectd/4
recti(X1, Y1, X2, Y2) -> ok
Types:
X1 = integer()
Y1 = integer()
X2 = integer()
Y2 = integer()
See rectd/4
rects(X1, Y1, X2, Y2) -> ok
Types:
X1 = integer()
Y1 = integer()
X2 = integer()
Y2 = integer()
See rectd/4
rectdv(V1, V2) -> ok
Types:
V1 = {float(), float()}
V2 = {float(), float()}
See rectd/4
rectfv(V1, V2) -> ok
Types:
V1 = {float(), float()}
V2 = {float(), float()}
See rectd/4
rectiv(V1, V2) -> ok
Types:
V1 = {integer(), integer()}
V2 = {integer(), integer()}
See rectd/4
rectsv(V1, V2) -> ok
Types:
V1 = {integer(), integer()}
V2 = {integer(), integer()}
See rectd/4
vertexPointer(Size, Type, Stride, Ptr) -> ok
Types:
Size = integer()
Type = enum()
Stride = integer()
Ptr = offset() | mem()
Define an array of vertex data
gl:vertexPointer specifies the location and data format of an array of vertex
coordinates to use when rendering. Size specifies the number of coordinates per
vertex, and must be 2, 3, or 4. Type specifies the data type of each coordinate,
and Stride specifies the byte stride from one vertex to the next, allowing vertices
and attributes to be packed into a single array or stored in separate arrays.
(Single-array storage may be more efficient on some implementations; see
gl:interleavedArrays/3 .)
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a vertex array is specified, Pointer is treated as a byte
offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as vertex array client-side state
(?GL_VERTEX_ARRAY_BUFFER_BINDING).
When a vertex array is specified, Size , Type , Stride , and Pointer are saved as
client-side state, in addition to the current vertex array buffer object binding.
To enable and disable the vertex array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_VERTEX_ARRAY. If enabled, the vertex
array is used when gl:arrayElement/1 , gl:drawArrays/3 , gl:multiDrawArrays/3 ,
gl:drawElements/4 , see glMultiDrawElements , or gl:drawRangeElements/6 is called.
See external documentation.
normalPointer(Type, Stride, Ptr) -> ok
Types:
Type = enum()
Stride = integer()
Ptr = offset() | mem()
Define an array of normals
gl:normalPointer specifies the location and data format of an array of normals to
use when rendering. Type specifies the data type of each normal coordinate, and
Stride specifies the byte stride from one normal to the next, allowing vertices and
attributes to be packed into a single array or stored in separate arrays. (Single-
array storage may be more efficient on some implementations; see
gl:interleavedArrays/3 .)
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a normal array is specified, Pointer is treated as a byte
offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as normal vertex array client-side state
(?GL_NORMAL_ARRAY_BUFFER_BINDING ).
When a normal array is specified, Type , Stride , and Pointer are saved as client-
side state, in addition to the current vertex array buffer object binding.
To enable and disable the normal array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_NORMAL_ARRAY. If enabled, the normal
array is used when gl:drawArrays/3 , gl:multiDrawArrays/3 , gl:drawElements/4 , see
glMultiDrawElements, gl:drawRangeElements/6 , or gl:arrayElement/1 is called.
See external documentation.
colorPointer(Size, Type, Stride, Ptr) -> ok
Types:
Size = integer()
Type = enum()
Stride = integer()
Ptr = offset() | mem()
Define an array of colors
gl:colorPointer specifies the location and data format of an array of color
components to use when rendering. Size specifies the number of components per
color, and must be 3 or 4. Type specifies the data type of each color component,
and Stride specifies the byte stride from one color to the next, allowing vertices
and attributes to be packed into a single array or stored in separate arrays.
(Single-array storage may be more efficient on some implementations; see
gl:interleavedArrays/3 .)
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a color array is specified, Pointer is treated as a byte
offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as color vertex array client-side state
(?GL_COLOR_ARRAY_BUFFER_BINDING).
When a color array is specified, Size , Type , Stride , and Pointer are saved as
client-side state, in addition to the current vertex array buffer object binding.
To enable and disable the color array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_COLOR_ARRAY. If enabled, the color
array is used when gl:drawArrays/3 , gl:multiDrawArrays/3 , gl:drawElements/4 , see
glMultiDrawElements, gl:drawRangeElements/6 , or gl:arrayElement/1 is called.
See external documentation.
indexPointer(Type, Stride, Ptr) -> ok
Types:
Type = enum()
Stride = integer()
Ptr = offset() | mem()
Define an array of color indexes
gl:indexPointer specifies the location and data format of an array of color indexes
to use when rendering. Type specifies the data type of each color index and Stride
specifies the byte stride from one color index to the next, allowing vertices and
attributes to be packed into a single array or stored in separate arrays.
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a color index array is specified, Pointer is treated as a
byte offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as color index vertex array client-side state
(?GL_INDEX_ARRAY_BUFFER_BINDING ).
When a color index array is specified, Type , Stride , and Pointer are saved as
client-side state, in addition to the current vertex array buffer object binding.
To enable and disable the color index array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_INDEX_ARRAY. If enabled, the color
index array is used when gl:drawArrays/3 , gl:multiDrawArrays/3 , gl:drawElements/4
, see glMultiDrawElements , gl:drawRangeElements/6 , or gl:arrayElement/1 is
called.
See external documentation.
texCoordPointer(Size, Type, Stride, Ptr) -> ok
Types:
Size = integer()
Type = enum()
Stride = integer()
Ptr = offset() | mem()
Define an array of texture coordinates
gl:texCoordPointer specifies the location and data format of an array of texture
coordinates to use when rendering. Size specifies the number of coordinates per
texture coordinate set, and must be 1, 2, 3, or 4. Type specifies the data type of
each texture coordinate, and Stride specifies the byte stride from one texture
coordinate set to the next, allowing vertices and attributes to be packed into a
single array or stored in separate arrays. (Single-array storage may be more
efficient on some implementations; see gl:interleavedArrays/3 .)
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a texture coordinate array is specified, Pointer is treated
as a byte offset into the buffer object's data store. Also, the buffer object
binding (?GL_ARRAY_BUFFER_BINDING ) is saved as texture coordinate vertex array
client-side state (?GL_TEXTURE_COORD_ARRAY_BUFFER_BINDING ).
When a texture coordinate array is specified, Size , Type , Stride , and Pointer
are saved as client-side state, in addition to the current vertex array buffer
object binding.
To enable and disable a texture coordinate array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_TEXTURE_COORD_ARRAY. If enabled, the
texture coordinate array is used when gl:arrayElement/1 , gl:drawArrays/3 ,
gl:multiDrawArrays/3 , gl:drawElements/4 , see glMultiDrawElements, or
gl:drawRangeElements/6 is called.
See external documentation.
edgeFlagPointer(Stride, Ptr) -> ok
Types:
Stride = integer()
Ptr = offset() | mem()
Define an array of edge flags
gl:edgeFlagPointer specifies the location and data format of an array of boolean
edge flags to use when rendering. Stride specifies the byte stride from one edge
flag to the next, allowing vertices and attributes to be packed into a single array
or stored in separate arrays.
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while an edge flag array is specified, Pointer is treated as a
byte offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as edge flag vertex array client-side state
(?GL_EDGE_FLAG_ARRAY_BUFFER_BINDING ).
When an edge flag array is specified, Stride and Pointer are saved as client-side
state, in addition to the current vertex array buffer object binding.
To enable and disable the edge flag array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_EDGE_FLAG_ARRAY. If enabled, the edge
flag array is used when gl:drawArrays/3 , gl:multiDrawArrays/3 , gl:drawElements/4
, see glMultiDrawElements , gl:drawRangeElements/6 , or gl:arrayElement/1 is
called.
See external documentation.
arrayElement(I) -> ok
Types:
I = integer()
Render a vertex using the specified vertex array element
gl:arrayElement commands are used within gl:'begin'/1 / gl:'begin'/1 pairs to
specify vertex and attribute data for point, line, and polygon primitives. If
?GL_VERTEX_ARRAY is enabled when gl:arrayElement is called, a single vertex is
drawn, using vertex and attribute data taken from location I of the enabled arrays.
If ?GL_VERTEX_ARRAY is not enabled, no drawing occurs but the attributes
corresponding to the enabled arrays are modified.
Use gl:arrayElement to construct primitives by indexing vertex data, rather than by
streaming through arrays of data in first-to-last order. Because each call
specifies only a single vertex, it is possible to explicitly specify per-primitive
attributes such as a single normal for each triangle.
Changes made to array data between the execution of gl:'begin'/1 and the
corresponding execution of gl:'begin'/1 may affect calls to gl:arrayElement that
are made within the same gl:'begin'/1 / gl:'begin'/1 period in nonsequential ways.
That is, a call to gl:arrayElement that precedes a change to array data may access
the changed data, and a call that follows a change to array data may access
original data.
See external documentation.
drawArrays(Mode, First, Count) -> ok
Types:
Mode = enum()
First = integer()
Count = integer()
Render primitives from array data
gl:drawArrays specifies multiple geometric primitives with very few subroutine
calls. Instead of calling a GL procedure to pass each individual vertex, normal,
texture coordinate, edge flag, or color, you can prespecify separate arrays of
vertices, normals, and colors and use them to construct a sequence of primitives
with a single call to gl:drawArrays .
When gl:drawArrays is called, it uses Count sequential elements from each enabled
array to construct a sequence of geometric primitives, beginning with element First
. Mode specifies what kind of primitives are constructed and how the array elements
construct those primitives.
Vertex attributes that are modified by gl:drawArrays have an unspecified value
after gl:drawArrays returns. Attributes that aren't modified remain well defined.
See external documentation.
drawElements(Mode, Count, Type, Indices) -> ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Render primitives from array data
gl:drawElements specifies multiple geometric primitives with very few subroutine
calls. Instead of calling a GL function to pass each individual vertex, normal,
texture coordinate, edge flag, or color, you can prespecify separate arrays of
vertices, normals, and so on, and use them to construct a sequence of primitives
with a single call to gl:drawElements .
When gl:drawElements is called, it uses Count sequential elements from an enabled
array, starting at Indices to construct a sequence of geometric primitives. Mode
specifies what kind of primitives are constructed and how the array elements
construct these primitives. If more than one array is enabled, each is used.
Vertex attributes that are modified by gl:drawElements have an unspecified value
after gl:drawElements returns. Attributes that aren't modified maintain their
previous values.
See external documentation.
interleavedArrays(Format, Stride, Pointer) -> ok
Types:
Format = enum()
Stride = integer()
Pointer = offset() | mem()
Simultaneously specify and enable several interleaved arrays
gl:interleavedArrays lets you specify and enable individual color, normal, texture
and vertex arrays whose elements are part of a larger aggregate array element. For
some implementations, this is more efficient than specifying the arrays separately.
If Stride is 0, the aggregate elements are stored consecutively. Otherwise, Stride
bytes occur between the beginning of one aggregate array element and the beginning
of the next aggregate array element.
Format serves as a key describing the extraction of individual arrays from the
aggregate array. If Format contains a T, then texture coordinates are extracted
from the interleaved array. If C is present, color values are extracted. If N is
present, normal coordinates are extracted. Vertex coordinates are always extracted.
The digits 2, 3, and 4 denote how many values are extracted. F indicates that
values are extracted as floating-point values. Colors may also be extracted as 4
unsigned bytes if 4UB follows the C. If a color is extracted as 4 unsigned bytes,
the vertex array element which follows is located at the first possible floating-
point aligned address.
See external documentation.
shadeModel(Mode) -> ok
Types:
Mode = enum()
Select flat or smooth shading
GL primitives can have either flat or smooth shading. Smooth shading, the default,
causes the computed colors of vertices to be interpolated as the primitive is
rasterized, typically assigning different colors to each resulting pixel fragment.
Flat shading selects the computed color of just one vertex and assigns it to all
the pixel fragments generated by rasterizing a single primitive. In either case,
the computed color of a vertex is the result of lighting if lighting is enabled, or
it is the current color at the time the vertex was specified if lighting is
disabled.
Flat and smooth shading are indistinguishable for points. Starting when
gl:'begin'/1 is issued and counting vertices and primitives from 1, the GL gives
each flat-shaded line segment i the computed color of vertex i+1, its second
vertex. Counting similarly from 1, the GL gives each flat-shaded polygon the
computed color of the vertex listed in the following table. This is the last vertex
to specify the polygon in all cases except single polygons, where the first vertex
specifies the flat-shaded color.Primitive Type of Polygon iVertex
Single polygon ( i== 1) 1
Triangle strip i+2
Triangle fan i+2
Independent triangle 3 i
Quad strip 2 i+2
Independent quad 4 i
Flat and smooth shading are specified by gl:shadeModel with Mode set to ?GL_FLAT
and ?GL_SMOOTH, respectively.
See external documentation.
lightf(Light, Pname, Param) -> ok
Types:
Light = enum()
Pname = enum()
Param = float()
Set light source parameters
gl:light sets the values of individual light source parameters. Light names the
light and is a symbolic name of the form ?GL_LIGHT i, where i ranges from 0 to the
value of ?GL_MAX_LIGHTS - 1. Pname specifies one of ten light source parameters,
again by symbolic name. Params is either a single value or a pointer to an array
that contains the new values.
To enable and disable lighting calculation, call gl:enable/1 and gl:enable/1 with
argument ?GL_LIGHTING. Lighting is initially disabled. When it is enabled, light
sources that are enabled contribute to the lighting calculation. Light source i is
enabled and disabled using gl:enable/1 and gl:enable/1 with argument ?GL_LIGHT i.
The ten light parameters are as follows:
?GL_AMBIENT: Params contains four integer or floating-point values that specify the
ambient RGBA intensity of the light. Integer values are mapped linearly such that
the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial ambient light
intensity is (0, 0, 0, 1).
?GL_DIFFUSE: Params contains four integer or floating-point values that specify the
diffuse RGBA intensity of the light. Integer values are mapped linearly such that
the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial value for
?GL_LIGHT0 is (1, 1, 1, 1); for other lights, the initial value is (0, 0, 0, 1).
?GL_SPECULAR: Params contains four integer or floating-point values that specify
the specular RGBA intensity of the light. Integer values are mapped linearly such
that the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial value for
?GL_LIGHT0 is (1, 1, 1, 1); for other lights, the initial value is (0, 0, 0, 1).
?GL_POSITION: Params contains four integer or floating-point values that specify
the position of the light in homogeneous object coordinates. Both integer and
floating-point values are mapped directly. Neither integer nor floating-point
values are clamped.
The position is transformed by the modelview matrix when gl:light is called (just
as if it were a point), and it is stored in eye coordinates. If the w component of
the position is 0, the light is treated as a directional source. Diffuse and
specular lighting calculations take the light's direction, but not its actual
position, into account, and attenuation is disabled. Otherwise, diffuse and
specular lighting calculations are based on the actual location of the light in eye
coordinates, and attenuation is enabled. The initial position is (0, 0, 1, 0);
thus, the initial light source is directional, parallel to, and in the direction of
the -z axis.
?GL_SPOT_DIRECTION: Params contains three integer or floating-point values that
specify the direction of the light in homogeneous object coordinates. Both integer
and floating-point values are mapped directly. Neither integer nor floating-point
values are clamped.
The spot direction is transformed by the upper 3x3 of the modelview matrix when
gl:light is called, and it is stored in eye coordinates. It is significant only
when ?GL_SPOT_CUTOFF is not 180, which it is initially. The initial direction is (0
0 -1).
?GL_SPOT_EXPONENT: Params is a single integer or floating-point value that
specifies the intensity distribution of the light. Integer and floating-point
values are mapped directly. Only values in the range [0 128] are accepted.
Effective light intensity is attenuated by the cosine of the angle between the
direction of the light and the direction from the light to the vertex being
lighted, raised to the power of the spot exponent. Thus, higher spot exponents
result in a more focused light source, regardless of the spot cutoff angle (see
?GL_SPOT_CUTOFF, next paragraph). The initial spot exponent is 0, resulting in
uniform light distribution.
?GL_SPOT_CUTOFF: Params is a single integer or floating-point value that specifies
the maximum spread angle of a light source. Integer and floating-point values are
mapped directly. Only values in the range [0 90] and the special value 180 are
accepted. If the angle between the direction of the light and the direction from
the light to the vertex being lighted is greater than the spot cutoff angle, the
light is completely masked. Otherwise, its intensity is controlled by the spot
exponent and the attenuation factors. The initial spot cutoff is 180, resulting in
uniform light distribution.
?GL_CONSTANT_ATTENUATION
?GL_LINEAR_ATTENUATION
?GL_QUADRATIC_ATTENUATION: Params is a single integer or floating-point value that
specifies one of the three light attenuation factors. Integer and floating-point
values are mapped directly. Only nonnegative values are accepted. If the light is
positional, rather than directional, its intensity is attenuated by the reciprocal
of the sum of the constant factor, the linear factor times the distance between the
light and the vertex being lighted, and the quadratic factor times the square of
the same distance. The initial attenuation factors are (1, 0, 0), resulting in no
attenuation.
See external documentation.
lighti(Light, Pname, Param) -> ok
Types:
Light = enum()
Pname = enum()
Param = integer()
See lightf/3
lightfv(Light, Pname, Params) -> ok
Types:
Light = enum()
Pname = enum()
Params = {float()}
See lightf/3
lightiv(Light, Pname, Params) -> ok
Types:
Light = enum()
Pname = enum()
Params = {integer()}
See lightf/3
getLightfv(Light, Pname) -> {float(), float(), float(), float()}
Types:
Light = enum()
Pname = enum()
Return light source parameter values
gl:getLight returns in Params the value or values of a light source parameter.
Light names the light and is a symbolic name of the form ?GL_LIGHT i where i ranges
from 0 to the value of ?GL_MAX_LIGHTS - 1. ?GL_MAX_LIGHTS is an implementation
dependent constant that is greater than or equal to eight. Pname specifies one of
ten light source parameters, again by symbolic name.
The following parameters are defined:
?GL_AMBIENT: Params returns four integer or floating-point values representing the
ambient intensity of the light source. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer value, and -1.0 maps to the most negative
representable integer value. If the internal value is outside the range [-1 1], the
corresponding integer return value is undefined. The initial value is (0, 0, 0, 1).
?GL_DIFFUSE: Params returns four integer or floating-point values representing the
diffuse intensity of the light source. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer value, and -1.0 maps to the most negative
representable integer value. If the internal value is outside the range [-1 1], the
corresponding integer return value is undefined. The initial value for ?GL_LIGHT0
is (1, 1, 1, 1); for other lights, the initial value is (0, 0, 0, 0).
?GL_SPECULAR: Params returns four integer or floating-point values representing the
specular intensity of the light source. Integer values, when requested, are
linearly mapped from the internal floating-point representation such that 1.0 maps
to the most positive representable integer value, and -1.0 maps to the most
negative representable integer value. If the internal value is outside the range
[-1 1], the corresponding integer return value is undefined. The initial value for
?GL_LIGHT0 is (1, 1, 1, 1); for other lights, the initial value is (0, 0, 0, 0).
?GL_POSITION: Params returns four integer or floating-point values representing the
position of the light source. Integer values, when requested, are computed by
rounding the internal floating-point values to the nearest integer value. The
returned values are those maintained in eye coordinates. They will not be equal to
the values specified using gl:lightf/3 , unless the modelview matrix was identity
at the time gl:lightf/3 was called. The initial value is (0, 0, 1, 0).
?GL_SPOT_DIRECTION: Params returns three integer or floating-point values
representing the direction of the light source. Integer values, when requested, are
computed by rounding the internal floating-point values to the nearest integer
value. The returned values are those maintained in eye coordinates. They will not
be equal to the values specified using gl:lightf/3 , unless the modelview matrix
was identity at the time gl:lightf/3 was called. Although spot direction is
normalized before being used in the lighting equation, the returned values are the
transformed versions of the specified values prior to normalization. The initial
value is (0 0 -1).
?GL_SPOT_EXPONENT: Params returns a single integer or floating-point value
representing the spot exponent of the light. An integer value, when requested, is
computed by rounding the internal floating-point representation to the nearest
integer. The initial value is 0.
?GL_SPOT_CUTOFF: Params returns a single integer or floating-point value
representing the spot cutoff angle of the light. An integer value, when requested,
is computed by rounding the internal floating-point representation to the nearest
integer. The initial value is 180.
?GL_CONSTANT_ATTENUATION: Params returns a single integer or floating-point value
representing the constant (not distance-related) attenuation of the light. An
integer value, when requested, is computed by rounding the internal floating-point
representation to the nearest integer. The initial value is 1.
?GL_LINEAR_ATTENUATION: Params returns a single integer or floating-point value
representing the linear attenuation of the light. An integer value, when requested,
is computed by rounding the internal floating-point representation to the nearest
integer. The initial value is 0.
?GL_QUADRATIC_ATTENUATION: Params returns a single integer or floating-point value
representing the quadratic attenuation of the light. An integer value, when
requested, is computed by rounding the internal floating-point representation to
the nearest integer. The initial value is 0.
See external documentation.
getLightiv(Light, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Light = enum()
Pname = enum()
See getLightfv/2
lightModelf(Pname, Param) -> ok
Types:
Pname = enum()
Param = float()
Set the lighting model parameters
gl:lightModel sets the lighting model parameter. Pname names a parameter and Params
gives the new value. There are three lighting model parameters:
?GL_LIGHT_MODEL_AMBIENT: Params contains four integer or floating-point values that
specify the ambient RGBA intensity of the entire scene. Integer values are mapped
linearly such that the most positive representable value maps to 1.0, and the most
negative representable value maps to -1.0. Floating-point values are mapped
directly. Neither integer nor floating-point values are clamped. The initial
ambient scene intensity is (0.2, 0.2, 0.2, 1.0).
?GL_LIGHT_MODEL_COLOR_CONTROL: Params must be either ?GL_SEPARATE_SPECULAR_COLOR or
?GL_SINGLE_COLOR. ?GL_SINGLE_COLOR specifies that a single color is generated from
the lighting computation for a vertex. ?GL_SEPARATE_SPECULAR_COLOR specifies that
the specular color computation of lighting be stored separately from the remainder
of the lighting computation. The specular color is summed into the generated
fragment's color after the application of texture mapping (if enabled). The initial
value is ?GL_SINGLE_COLOR.
?GL_LIGHT_MODEL_LOCAL_VIEWER: Params is a single integer or floating-point value
that specifies how specular reflection angles are computed. If Params is 0 (or
0.0), specular reflection angles take the view direction to be parallel to and in
the direction of the -z axis, regardless of the location of the vertex in eye
coordinates. Otherwise, specular reflections are computed from the origin of the
eye coordinate system. The initial value is 0.
?GL_LIGHT_MODEL_TWO_SIDE: Params is a single integer or floating-point value that
specifies whether one- or two-sided lighting calculations are done for polygons. It
has no effect on the lighting calculations for points, lines, or bitmaps. If Params
is 0 (or 0.0), one-sided lighting is specified, and only the front material
parameters are used in the lighting equation. Otherwise, two-sided lighting is
specified. In this case, vertices of back-facing polygons are lighted using the
back material parameters and have their normals reversed before the lighting
equation is evaluated. Vertices of front-facing polygons are always lighted using
the front material parameters, with no change to their normals. The initial value
is 0.
In RGBA mode, the lighted color of a vertex is the sum of the material emission
intensity, the product of the material ambient reflectance and the lighting model
full-scene ambient intensity, and the contribution of each enabled light source.
Each light source contributes the sum of three terms: ambient, diffuse, and
specular. The ambient light source contribution is the product of the material
ambient reflectance and the light's ambient intensity. The diffuse light source
contribution is the product of the material diffuse reflectance, the light's
diffuse intensity, and the dot product of the vertex's normal with the normalized
vector from the vertex to the light source. The specular light source contribution
is the product of the material specular reflectance, the light's specular
intensity, and the dot product of the normalized vertex-to-eye and vertex-to-light
vectors, raised to the power of the shininess of the material. All three light
source contributions are attenuated equally based on the distance from the vertex
to the light source and on light source direction, spread exponent, and spread
cutoff angle. All dot products are replaced with 0 if they evaluate to a negative
value.
The alpha component of the resulting lighted color is set to the alpha value of the
material diffuse reflectance.
In color index mode, the value of the lighted index of a vertex ranges from the
ambient to the specular values passed to gl:materialf/3 using ?GL_COLOR_INDEXES.
Diffuse and specular coefficients, computed with a (.30, .59, .11) weighting of the
lights' colors, the shininess of the material, and the same reflection and
attenuation equations as in the RGBA case, determine how much above ambient the
resulting index is.
See external documentation.
lightModeli(Pname, Param) -> ok
Types:
Pname = enum()
Param = integer()
See lightModelf/2
lightModelfv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {float()}
See lightModelf/2
lightModeliv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {integer()}
See lightModelf/2
materialf(Face, Pname, Param) -> ok
Types:
Face = enum()
Pname = enum()
Param = float()
Specify material parameters for the lighting model
gl:material assigns values to material parameters. There are two matched sets of
material parameters. One, the front-facing set, is used to shade points, lines,
bitmaps, and all polygons (when two-sided lighting is disabled), or just front-
facing polygons (when two-sided lighting is enabled). The other set, back-facing,
is used to shade back-facing polygons only when two-sided lighting is enabled.
Refer to the gl:lightModelf/2 reference page for details concerning one- and two-
sided lighting calculations.
gl:material takes three arguments. The first, Face , specifies whether the
?GL_FRONT materials, the ?GL_BACK materials, or both ?GL_FRONT_AND_BACK materials
will be modified. The second, Pname , specifies which of several parameters in one
or both sets will be modified. The third, Params , specifies what value or values
will be assigned to the specified parameter.
Material parameters are used in the lighting equation that is optionally applied to
each vertex. The equation is discussed in the gl:lightModelf/2 reference page. The
parameters that can be specified using gl:material, and their interpretations by
the lighting equation, are as follows:
?GL_AMBIENT: Params contains four integer or floating-point values that specify the
ambient RGBA reflectance of the material. Integer values are mapped linearly such
that the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial ambient
reflectance for both front- and back-facing materials is (0.2, 0.2, 0.2, 1.0).
?GL_DIFFUSE: Params contains four integer or floating-point values that specify the
diffuse RGBA reflectance of the material. Integer values are mapped linearly such
that the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial diffuse
reflectance for both front- and back-facing materials is (0.8, 0.8, 0.8, 1.0).
?GL_SPECULAR: Params contains four integer or floating-point values that specify
the specular RGBA reflectance of the material. Integer values are mapped linearly
such that the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. Floating-point values are mapped directly.
Neither integer nor floating-point values are clamped. The initial specular
reflectance for both front- and back-facing materials is (0, 0, 0, 1).
?GL_EMISSION: Params contains four integer or floating-point values that specify
the RGBA emitted light intensity of the material. Integer values are mapped
linearly such that the most positive representable value maps to 1.0, and the most
negative representable value maps to -1.0. Floating-point values are mapped
directly. Neither integer nor floating-point values are clamped. The initial
emission intensity for both front- and back-facing materials is (0, 0, 0, 1).
?GL_SHININESS: Params is a single integer or floating-point value that specifies
the RGBA specular exponent of the material. Integer and floating-point values are
mapped directly. Only values in the range [0 128] are accepted. The initial
specular exponent for both front- and back-facing materials is 0.
?GL_AMBIENT_AND_DIFFUSE: Equivalent to calling gl:material twice with the same
parameter values, once with ?GL_AMBIENT and once with ?GL_DIFFUSE.
?GL_COLOR_INDEXES: Params contains three integer or floating-point values
specifying the color indices for ambient, diffuse, and specular lighting. These
three values, and ?GL_SHININESS, are the only material values used by the color
index mode lighting equation. Refer to the gl:lightModelf/2 reference page for a
discussion of color index lighting.
See external documentation.
materiali(Face, Pname, Param) -> ok
Types:
Face = enum()
Pname = enum()
Param = integer()
See materialf/3
materialfv(Face, Pname, Params) -> ok
Types:
Face = enum()
Pname = enum()
Params = {float()}
See materialf/3
materialiv(Face, Pname, Params) -> ok
Types:
Face = enum()
Pname = enum()
Params = {integer()}
See materialf/3
getMaterialfv(Face, Pname) -> {float(), float(), float(), float()}
Types:
Face = enum()
Pname = enum()
Return material parameters
gl:getMaterial returns in Params the value or values of parameter Pname of material
Face . Six parameters are defined:
?GL_AMBIENT: Params returns four integer or floating-point values representing the
ambient reflectance of the material. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer value, and -1.0 maps to the most negative
representable integer value. If the internal value is outside the range [-1 1], the
corresponding integer return value is undefined. The initial value is (0.2, 0.2,
0.2, 1.0)
?GL_DIFFUSE: Params returns four integer or floating-point values representing the
diffuse reflectance of the material. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer value, and -1.0 maps to the most negative
representable integer value. If the internal value is outside the range [-1 1], the
corresponding integer return value is undefined. The initial value is (0.8, 0.8,
0.8, 1.0).
?GL_SPECULAR: Params returns four integer or floating-point values representing the
specular reflectance of the material. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer value, and -1.0 maps to the most negative
representable integer value. If the internal value is outside the range [-1 1], the
corresponding integer return value is undefined. The initial value is (0, 0, 0, 1).
?GL_EMISSION: Params returns four integer or floating-point values representing the
emitted light intensity of the material. Integer values, when requested, are
linearly mapped from the internal floating-point representation such that 1.0 maps
to the most positive representable integer value, and -1.0 maps to the most
negative representable integer value. If the internal value is outside the range
[-1 1], the corresponding integer return value is undefined. The initial value is
(0, 0, 0, 1).
?GL_SHININESS: Params returns one integer or floating-point value representing the
specular exponent of the material. Integer values, when requested, are computed by
rounding the internal floating-point value to the nearest integer value. The
initial value is 0.
?GL_COLOR_INDEXES: Params returns three integer or floating-point values
representing the ambient, diffuse, and specular indices of the material. These
indices are used only for color index lighting. (All the other parameters are used
only for RGBA lighting.) Integer values, when requested, are computed by rounding
the internal floating-point values to the nearest integer values.
See external documentation.
getMaterialiv(Face, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Face = enum()
Pname = enum()
See getMaterialfv/2
colorMaterial(Face, Mode) -> ok
Types:
Face = enum()
Mode = enum()
Cause a material color to track the current color
gl:colorMaterial specifies which material parameters track the current color. When
?GL_COLOR_MATERIAL is enabled, the material parameter or parameters specified by
Mode , of the material or materials specified by Face , track the current color at
all times.
To enable and disable ?GL_COLOR_MATERIAL, call gl:enable/1 and gl:enable/1 with
argument ?GL_COLOR_MATERIAL. ?GL_COLOR_MATERIAL is initially disabled.
See external documentation.
pixelZoom(Xfactor, Yfactor) -> ok
Types:
Xfactor = float()
Yfactor = float()
Specify the pixel zoom factors
gl:pixelZoom specifies values for the x and y zoom factors. During the execution of
gl:drawPixels/5 or gl:copyPixels/5 , if ( xr, yr) is the current raster position,
and a given element is in the mth row and nth column of the pixel rectangle, then
pixels whose centers are in the rectangle with corners at
( xr+n. xfactor, yr+m. yfactor)
( xr+(n+1). xfactor, yr+(m+1). yfactor)
are candidates for replacement. Any pixel whose center lies on the bottom or left
edge of this rectangular region is also modified.
Pixel zoom factors are not limited to positive values. Negative zoom factors
reflect the resulting image about the current raster position.
See external documentation.
pixelStoref(Pname, Param) -> ok
Types:
Pname = enum()
Param = float()
Set pixel storage modes
gl:pixelStore sets pixel storage modes that affect the operation of subsequent
gl:readPixels/7 as well as the unpacking of texture patterns (see gl:texImage1D/8 ,
gl:texImage2D/9 , gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 ,
gl:texSubImage1D/7 ), gl:compressedTexImage1D/7 , gl:compressedTexImage2D/8 ,
gl:compressedTexImage3D/9 , gl:compressedTexSubImage1D/7 ,
gl:compressedTexSubImage2D/9 or gl:compressedTexSubImage1D/7 .
Pname is a symbolic constant indicating the parameter to be set, and Param is the
new value. Six of the twelve storage parameters affect how pixel data is returned
to client memory. They are as follows:
?GL_PACK_SWAP_BYTES: If true, byte ordering for multibyte color components, depth
components, or stencil indices is reversed. That is, if a four-byte component
consists of bytes b 0, b 1, b 2, b 3, it is stored in memory as b 3, b 2, b 1, b 0
if ?GL_PACK_SWAP_BYTES is true. ?GL_PACK_SWAP_BYTES has no effect on the memory
order of components within a pixel, only on the order of bytes within components or
indices. For example, the three components of a ?GL_RGB format pixel are always
stored with red first, green second, and blue third, regardless of the value of
?GL_PACK_SWAP_BYTES.
?GL_PACK_LSB_FIRST: If true, bits are ordered within a byte from least significant
to most significant; otherwise, the first bit in each byte is the most significant
one.
?GL_PACK_ROW_LENGTH: If greater than 0, ?GL_PACK_ROW_LENGTH defines the number of
pixels in a row. If the first pixel of a row is placed at location p in memory,
then the location of the first pixel of the next row is obtained by skipping
k={n l(a/s) |(s n l)/a| s>= a s< a)
components or indices, where n is the number of components or indices in a pixel, l
is the number of pixels in a row (?GL_PACK_ROW_LENGTH if it is greater than 0, the
width argument to the pixel routine otherwise), a is the value of
?GL_PACK_ALIGNMENT , and s is the size, in bytes, of a single component (if a< s,
then it is as if a= s). In the case of 1-bit values, the location of the next row
is obtained by skipping
k=8 a |(n l)/(8 a)|
components or indices.
The word component in this description refers to the nonindex values red, green,
blue, alpha, and depth. Storage format ?GL_RGB, for example, has three components
per pixel: first red, then green, and finally blue.
?GL_PACK_IMAGE_HEIGHT: If greater than 0, ?GL_PACK_IMAGE_HEIGHT defines the number
of pixels in an image three-dimensional texture volume, where image is defined by
all pixels sharing the same third dimension index. If the first pixel of a row is
placed at location p in memory, then the location of the first pixel of the next
row is obtained by skipping
k={n l h(a/s) |(s n l h)/a| s>= a s< a)
components or indices, where n is the number of components or indices in a pixel, l
is the number of pixels in a row (?GL_PACK_ROW_LENGTH if it is greater than 0, the
width argument to gl:texImage3D/10 otherwise), h is the number of rows in a pixel
image (?GL_PACK_IMAGE_HEIGHT if it is greater than 0, the height argument to the
gl:texImage3D/10 routine otherwise), a is the value of ?GL_PACK_ALIGNMENT , and s
is the size, in bytes, of a single component (if a< s, then it is as if a=s).
The word component in this description refers to the nonindex values red, green,
blue, alpha, and depth. Storage format ?GL_RGB, for example, has three components
per pixel: first red, then green, and finally blue.
?GL_PACK_SKIP_PIXELS, ?GL_PACK_SKIP_ROWS, and ?GL_PACK_SKIP_IMAGES
These values are provided as a convenience to the programmer; they provide no
functionality that cannot be duplicated simply by incrementing the pointer passed
to gl:readPixels/7 . Setting ?GL_PACK_SKIP_PIXELS to i is equivalent to
incrementing the pointer by i n components or indices, where n is the number of
components or indices in each pixel. Setting ?GL_PACK_SKIP_ROWS to j is equivalent
to incrementing the pointer by j m components or indices, where m is the number of
components or indices per row, as just computed in the ?GL_PACK_ROW_LENGTH section.
Setting ?GL_PACK_SKIP_IMAGES to k is equivalent to incrementing the pointer by k p,
where p is the number of components or indices per image, as computed in the
?GL_PACK_IMAGE_HEIGHT section.
?GL_PACK_ALIGNMENT: Specifies the alignment requirements for the start of each
pixel row in memory. The allowable values are 1 (byte-alignment), 2 (rows aligned
to even-numbered bytes), 4 (word-alignment), and 8 (rows start on double-word
boundaries).
The other six of the twelve storage parameters affect how pixel data is read from
client memory. These values are significant for gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 , and gl:texSubImage1D/7
They are as follows:
?GL_UNPACK_SWAP_BYTES: If true, byte ordering for multibyte color components, depth
components, or stencil indices is reversed. That is, if a four-byte component
consists of bytes b 0, b 1, b 2, b 3, it is taken from memory as b 3, b 2, b 1, b 0
if ?GL_UNPACK_SWAP_BYTES is true. ?GL_UNPACK_SWAP_BYTES has no effect on the memory
order of components within a pixel, only on the order of bytes within components or
indices. For example, the three components of a ?GL_RGB format pixel are always
stored with red first, green second, and blue third, regardless of the value of
?GL_UNPACK_SWAP_BYTES.
?GL_UNPACK_LSB_FIRST: If true, bits are ordered within a byte from least
significant to most significant; otherwise, the first bit in each byte is the most
significant one.
?GL_UNPACK_ROW_LENGTH: If greater than 0, ?GL_UNPACK_ROW_LENGTH defines the number
of pixels in a row. If the first pixel of a row is placed at location p in memory,
then the location of the first pixel of the next row is obtained by skipping
k={n l(a/s) |(s n l)/a| s>= a s< a)
components or indices, where n is the number of components or indices in a pixel, l
is the number of pixels in a row (?GL_UNPACK_ROW_LENGTH if it is greater than 0,
the width argument to the pixel routine otherwise), a is the value of
?GL_UNPACK_ALIGNMENT , and s is the size, in bytes, of a single component (if a< s,
then it is as if a= s). In the case of 1-bit values, the location of the next row
is obtained by skipping
k=8 a |(n l)/(8 a)|
components or indices.
The word component in this description refers to the nonindex values red, green,
blue, alpha, and depth. Storage format ?GL_RGB, for example, has three components
per pixel: first red, then green, and finally blue.
?GL_UNPACK_IMAGE_HEIGHT: If greater than 0, ?GL_UNPACK_IMAGE_HEIGHT defines the
number of pixels in an image of a three-dimensional texture volume. Where image is
defined by all pixel sharing the same third dimension index. If the first pixel of
a row is placed at location p in memory, then the location of the first pixel of
the next row is obtained by skipping
k={n l h(a/s) |(s n l h)/a| s>= a s< a)
components or indices, where n is the number of components or indices in a pixel, l
is the number of pixels in a row (?GL_UNPACK_ROW_LENGTH if it is greater than 0,
the width argument to gl:texImage3D/10 otherwise), h is the number of rows in an
image (?GL_UNPACK_IMAGE_HEIGHT if it is greater than 0, the height argument to
gl:texImage3D/10 otherwise), a is the value of ?GL_UNPACK_ALIGNMENT, and s is the
size, in bytes, of a single component (if a< s, then it is as if a=s).
The word component in this description refers to the nonindex values red, green,
blue, alpha, and depth. Storage format ?GL_RGB, for example, has three components
per pixel: first red, then green, and finally blue.
?GL_UNPACK_SKIP_PIXELS and ?GL_UNPACK_SKIP_ROWS
These values are provided as a convenience to the programmer; they provide no
functionality that cannot be duplicated by incrementing the pointer passed to
gl:texImage1D/8 , gl:texImage2D/9 , gl:texSubImage1D/7 or gl:texSubImage1D/7 .
Setting ?GL_UNPACK_SKIP_PIXELS to i is equivalent to incrementing the pointer by i
n components or indices, where n is the number of components or indices in each
pixel. Setting ?GL_UNPACK_SKIP_ROWS to j is equivalent to incrementing the pointer
by j k components or indices, where k is the number of components or indices per
row, as just computed in the ?GL_UNPACK_ROW_LENGTH section.
?GL_UNPACK_ALIGNMENT: Specifies the alignment requirements for the start of each
pixel row in memory. The allowable values are 1 (byte-alignment), 2 (rows aligned
to even-numbered bytes), 4 (word-alignment), and 8 (rows start on double-word
boundaries).
The following table gives the type, initial value, and range of valid values for
each storage parameter that can be set with gl:pixelStore.PnameTypeInitial
ValueValid Range
?GL_PACK_SWAP_BYTES boolean false true or false
?GL_PACK_LSB_FIRST boolean false true or false
?GL_PACK_ROW_LENGTH integer 0 [0)
?GL_PACK_IMAGE_HEIGHT integer 0 [0)
?GL_PACK_SKIP_ROWS integer 0 [0)
?GL_PACK_SKIP_PIXELS integer 0 [0)
?GL_PACK_SKIP_IMAGES integer 0 [0)
?GL_PACK_ALIGNMENT integer 4 1, 2, 4, or 8
?GL_UNPACK_SWAP_BYTES boolean false true or false
?GL_UNPACK_LSB_FIRST boolean false true or false
?GL_UNPACK_ROW_LENGTH integer 0 [0)
?GL_UNPACK_IMAGE_HEIGHT integer 0 [0)
?GL_UNPACK_SKIP_ROWS integer 0 [0)
?GL_UNPACK_SKIP_PIXELS integer 0 [0)
?GL_UNPACK_SKIP_IMAGES integer 0 [0)
?GL_UNPACK_ALIGNMENT integer 4 1, 2, 4, or 8
gl:pixelStoref can be used to set any pixel store parameter. If the parameter type
is boolean, then if Param is 0, the parameter is false; otherwise it is set to
true. If Pname is a integer type parameter, Param is rounded to the nearest
integer.
Likewise, gl:pixelStorei can also be used to set any of the pixel store parameters.
Boolean parameters are set to false if Param is 0 and true otherwise.
See external documentation.
pixelStorei(Pname, Param) -> ok
Types:
Pname = enum()
Param = integer()
See pixelStoref/2
pixelTransferf(Pname, Param) -> ok
Types:
Pname = enum()
Param = float()
Set pixel transfer modes
gl:pixelTransfer sets pixel transfer modes that affect the operation of subsequent
gl:copyPixels/5 , gl:copyTexImage1D/7 , gl:copyTexImage2D/8 ,
gl:copyTexSubImage1D/6 , gl:copyTexSubImage2D/8 , gl:copyTexSubImage3D/9 ,
gl:drawPixels/5 , gl:readPixels/7 , gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 , and gl:texSubImage1D/7
commands. Additionally, if the ARB_imaging subset is supported, the routines
gl:colorTable/6 , gl:colorSubTable/6 , gl:convolutionFilter1D/6 ,
gl:convolutionFilter2D/7 , gl:histogram/4 , gl:minmax/3 , and
gl:separableFilter2D/8 are also affected. The algorithms that are specified by
pixel transfer modes operate on pixels after they are read from the frame buffer (
gl:copyPixels/5 gl:copyTexImage1D/7 , gl:copyTexImage2D/8 , gl:copyTexSubImage1D/6
, gl:copyTexSubImage2D/8 , gl:copyTexSubImage3D/9 , and gl:readPixels/7 ), or
unpacked from client memory ( gl:drawPixels/5 , gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 , and gl:texSubImage1D/7
). Pixel transfer operations happen in the same order, and in the same manner,
regardless of the command that resulted in the pixel operation. Pixel storage modes
(see gl:pixelStoref/2 ) control the unpacking of pixels being read from client
memory and the packing of pixels being written back into client memory.
Pixel transfer operations handle four fundamental pixel types: color, color index ,
depth, and stencil. Color pixels consist of four floating-point values with
unspecified mantissa and exponent sizes, scaled such that 0 represents zero
intensity and 1 represents full intensity. Color indices comprise a single fixed-
point value, with unspecified precision to the right of the binary point. Depth
pixels comprise a single floating-point value, with unspecified mantissa and
exponent sizes, scaled such that 0.0 represents the minimum depth buffer value, and
1.0 represents the maximum depth buffer value. Finally, stencil pixels comprise a
single fixed-point value, with unspecified precision to the right of the binary
point.
The pixel transfer operations performed on the four basic pixel types are as
follows:
Color: Each of the four color components is multiplied by a scale factor, then
added to a bias factor. That is, the red component is multiplied by ?GL_RED_SCALE,
then added to ?GL_RED_BIAS; the green component is multiplied by ?GL_GREEN_SCALE ,
then added to ?GL_GREEN_BIAS; the blue component is multiplied by ?GL_BLUE_SCALE ,
then added to ?GL_BLUE_BIAS; and the alpha component is multiplied by
?GL_ALPHA_SCALE , then added to ?GL_ALPHA_BIAS. After all four color components are
scaled and biased, each is clamped to the range [0 1]. All color, scale, and bias
values are specified with gl:pixelTransfer.
If ?GL_MAP_COLOR is true, each color component is scaled by the size of the
corresponding color-to-color map, then replaced by the contents of that map indexed
by the scaled component. That is, the red component is scaled by
?GL_PIXEL_MAP_R_TO_R_SIZE, then replaced by the contents of ?GL_PIXEL_MAP_R_TO_R
indexed by itself. The green component is scaled by ?GL_PIXEL_MAP_G_TO_G_SIZE, then
replaced by the contents of ?GL_PIXEL_MAP_G_TO_G indexed by itself. The blue
component is scaled by ?GL_PIXEL_MAP_B_TO_B_SIZE, then replaced by the contents of
?GL_PIXEL_MAP_B_TO_B indexed by itself. And the alpha component is scaled by
?GL_PIXEL_MAP_A_TO_A_SIZE, then replaced by the contents of ?GL_PIXEL_MAP_A_TO_A
indexed by itself. All components taken from the maps are then clamped to the range
[0 1]. ?GL_MAP_COLOR is specified with gl:pixelTransfer. The contents of the
various maps are specified with gl:pixelMapfv/3 .
If the ARB_imaging extension is supported, each of the four color components may be
scaled and biased after transformation by the color matrix. That is, the red
component is multiplied by ?GL_POST_COLOR_MATRIX_RED_SCALE, then added to
?GL_POST_COLOR_MATRIX_RED_BIAS ; the green component is multiplied by
?GL_POST_COLOR_MATRIX_GREEN_SCALE, then added to ?GL_POST_COLOR_MATRIX_GREEN_BIAS;
the blue component is multiplied by ?GL_POST_COLOR_MATRIX_BLUE_SCALE , then added
to ?GL_POST_COLOR_MATRIX_BLUE_BIAS; and the alpha component is multiplied by
?GL_POST_COLOR_MATRIX_ALPHA_SCALE, then added to ?GL_POST_COLOR_MATRIX_ALPHA_BIAS .
After all four color components are scaled and biased, each is clamped to the range
[0 1].
Similarly, if the ARB_imaging extension is supported, each of the four color
components may be scaled and biased after processing by the enabled convolution
filter. That is, the red component is multiplied by ?GL_POST_CONVOLUTION_RED_SCALE,
then added to ?GL_POST_CONVOLUTION_RED_BIAS ; the green component is multiplied by
?GL_POST_CONVOLUTION_GREEN_SCALE, then added to ?GL_POST_CONVOLUTION_GREEN_BIAS;
the blue component is multiplied by ?GL_POST_CONVOLUTION_BLUE_SCALE , then added to
?GL_POST_CONVOLUTION_BLUE_BIAS; and the alpha component is multiplied by
?GL_POST_CONVOLUTION_ALPHA_SCALE, then added to ?GL_POST_CONVOLUTION_ALPHA_BIAS .
After all four color components are scaled and biased, each is clamped to the range
[0 1].
Color index: Each color index is shifted left by ?GL_INDEX_SHIFT bits; any bits
beyond the number of fraction bits carried by the fixed-point index are filled with
zeros. If ?GL_INDEX_SHIFT is negative, the shift is to the right, again zero
filled. Then ?GL_INDEX_OFFSET is added to the index. ?GL_INDEX_SHIFT and
?GL_INDEX_OFFSET are specified with gl:pixelTransfer.
From this point, operation diverges depending on the required format of the
resulting pixels. If the resulting pixels are to be written to a color index
buffer, or if they are being read back to client memory in ?GL_COLOR_INDEX format,
the pixels continue to be treated as indices. If ?GL_MAP_COLOR is true, each index
is masked by 2 n-1 , where n is ?GL_PIXEL_MAP_I_TO_I_SIZE, then replaced by the
contents of ?GL_PIXEL_MAP_I_TO_I indexed by the masked value. ?GL_MAP_COLOR is
specified with gl:pixelTransfer . The contents of the index map is specified with
gl:pixelMapfv/3 .
If the resulting pixels are to be written to an RGBA color buffer, or if they are
read back to client memory in a format other than ?GL_COLOR_INDEX, the pixels are
converted from indices to colors by referencing the four maps ?GL_PIXEL_MAP_I_TO_R,
?GL_PIXEL_MAP_I_TO_G , ?GL_PIXEL_MAP_I_TO_B, and ?GL_PIXEL_MAP_I_TO_A. Before being
dereferenced, the index is masked by 2 n-1, where n is ?GL_PIXEL_MAP_I_TO_R_SIZE
for the red map, ?GL_PIXEL_MAP_I_TO_G_SIZE for the green map,
?GL_PIXEL_MAP_I_TO_B_SIZE for the blue map, and ?GL_PIXEL_MAP_I_TO_A_SIZE for the
alpha map. All components taken from the maps are then clamped to the range [0 1].
The contents of the four maps is specified with gl:pixelMapfv/3 .
Depth: Each depth value is multiplied by ?GL_DEPTH_SCALE, added to ?GL_DEPTH_BIAS ,
then clamped to the range [0 1].
Stencil: Each index is shifted ?GL_INDEX_SHIFT bits just as a color index is, then
added to ?GL_INDEX_OFFSET. If ?GL_MAP_STENCIL is true, each index is masked by 2
n-1, where n is ?GL_PIXEL_MAP_S_TO_S_SIZE, then replaced by the contents of
?GL_PIXEL_MAP_S_TO_S indexed by the masked value.
The following table gives the type, initial value, and range of valid values for
each of the pixel transfer parameters that are set with
gl:pixelTransfer.PnameTypeInitial ValueValid Range
?GL_MAP_COLOR boolean false true/false
?GL_MAP_STENCIL boolean false true/false
?GL_INDEX_SHIFT integer 0 (-)
?GL_INDEX_OFFSET integer 0 (-)
?GL_RED_SCALE float 1 (-)
?GL_GREEN_SCALE float 1 (-)
?GL_BLUE_SCALE float 1 (-)
?GL_ALPHA_SCALE float 1 (-)
?GL_DEPTH_SCALE float 1 (-)
?GL_RED_BIAS float 0 (-)
?GL_GREEN_BIAS float 0 (-)
?GL_BLUE_BIAS float 0 (-)
?GL_ALPHA_BIAS float 0 (-)
?GL_DEPTH_BIAS float 0 (-)
?GL_POST_COLOR_MATRIX_RED_SCALE float 1 (-)
?GL_POST_COLOR_MATRIX_GREEN_SCALE float 1 (-)
?GL_POST_COLOR_MATRIX_BLUE_SCALE float 1 (-)
?GL_POST_COLOR_MATRIX_ALPHA_SCALE float 1 (-)
?GL_POST_COLOR_MATRIX_RED_BIAS float 0 (-)
?GL_POST_COLOR_MATRIX_GREEN_BIAS float 0 (-)
?GL_POST_COLOR_MATRIX_BLUE_BIAS float 0 (-)
?GL_POST_COLOR_MATRIX_ALPHA_BIAS float 0 (-)
?GL_POST_CONVOLUTION_RED_SCALE float 1 (-)
?GL_POST_CONVOLUTION_GREEN_SCALE float 1 (-)
?GL_POST_CONVOLUTION_BLUE_SCALE float 1 (-)
?GL_POST_CONVOLUTION_ALPHA_SCALE float 1 (-)
?GL_POST_CONVOLUTION_RED_BIAS float 0 (-)
?GL_POST_CONVOLUTION_GREEN_BIAS float 0 (-)
?GL_POST_CONVOLUTION_BLUE_BIAS float 0 (-)
?GL_POST_CONVOLUTION_ALPHA_BIAS float 0 (-)
gl:pixelTransferf can be used to set any pixel transfer parameter. If the parameter
type is boolean, 0 implies false and any other value implies true. If Pname is an
integer parameter, Param is rounded to the nearest integer.
Likewise, gl:pixelTransferi can be used to set any of the pixel transfer
parameters. Boolean parameters are set to false if Param is 0 and to true
otherwise. Param is converted to floating point before being assigned to real-
valued parameters.
See external documentation.
pixelTransferi(Pname, Param) -> ok
Types:
Pname = enum()
Param = integer()
See pixelTransferf/2
pixelMapfv(Map, Mapsize, Values) -> ok
Types:
Map = enum()
Mapsize = integer()
Values = binary()
Set up pixel transfer maps
gl:pixelMap sets up translation tables, or maps, used by gl:copyPixels/5 ,
gl:copyTexImage1D/7 , gl:copyTexImage2D/8 , gl:copyTexSubImage1D/6 ,
gl:copyTexSubImage2D/8 , gl:copyTexSubImage3D/9 , gl:drawPixels/5 , gl:readPixels/7
, gl:texImage1D/8 , gl:texImage2D/9 , gl:texImage3D/10 , gl:texSubImage1D/7 ,
gl:texSubImage1D/7 , and gl:texSubImage1D/7 . Additionally, if the ARB_imaging
subset is supported, the routines gl:colorTable/6 , gl:colorSubTable/6 ,
gl:convolutionFilter1D/6 , gl:convolutionFilter2D/7 , gl:histogram/4 , gl:minmax/3
, and gl:separableFilter2D/8 . Use of these maps is described completely in the
gl:pixelTransferf/2 reference page, and partly in the reference pages for the pixel
and texture image commands. Only the specification of the maps is described in this
reference page.
Map is a symbolic map name, indicating one of ten maps to set. Mapsize specifies
the number of entries in the map, and Values is a pointer to an array of Mapsize
map values.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a pixel transfer map is specified, Values is treated
as a byte offset into the buffer object's data store.
The ten maps are as follows:
?GL_PIXEL_MAP_I_TO_I: Maps color indices to color indices.
?GL_PIXEL_MAP_S_TO_S: Maps stencil indices to stencil indices.
?GL_PIXEL_MAP_I_TO_R: Maps color indices to red components.
?GL_PIXEL_MAP_I_TO_G: Maps color indices to green components.
?GL_PIXEL_MAP_I_TO_B: Maps color indices to blue components.
?GL_PIXEL_MAP_I_TO_A: Maps color indices to alpha components.
?GL_PIXEL_MAP_R_TO_R: Maps red components to red components.
?GL_PIXEL_MAP_G_TO_G: Maps green components to green components.
?GL_PIXEL_MAP_B_TO_B: Maps blue components to blue components.
?GL_PIXEL_MAP_A_TO_A: Maps alpha components to alpha components.
The entries in a map can be specified as single-precision floating-point numbers,
unsigned short integers, or unsigned int integers. Maps that store color component
values (all but ?GL_PIXEL_MAP_I_TO_I and ?GL_PIXEL_MAP_S_TO_S) retain their values
in floating-point format, with unspecified mantissa and exponent sizes. Floating-
point values specified by gl:pixelMapfv are converted directly to the internal
floating-point format of these maps, then clamped to the range [0,1]. Unsigned
integer values specified by gl:pixelMapusv and gl:pixelMapuiv are converted
linearly such that the largest representable integer maps to 1.0, and 0 maps to
0.0.
Maps that store indices, ?GL_PIXEL_MAP_I_TO_I and ?GL_PIXEL_MAP_S_TO_S, retain
their values in fixed-point format, with an unspecified number of bits to the right
of the binary point. Floating-point values specified by gl:pixelMapfv are converted
directly to the internal fixed-point format of these maps. Unsigned integer values
specified by gl:pixelMapusv and gl:pixelMapuiv specify integer values, with all 0's
to the right of the binary point.
The following table shows the initial sizes and values for each of the maps. Maps
that are indexed by either color or stencil indices must have Mapsize = 2 n for
some n or the results are undefined. The maximum allowable size for each map
depends on the implementation and can be determined by calling gl:getBooleanv/1
with argument ?GL_MAX_PIXEL_MAP_TABLE . The single maximum applies to all maps; it
is at least 32.MapLookup IndexLookup ValueInitial SizeInitial Value
?GL_PIXEL_MAP_I_TO_I color index color index 1 0
?GL_PIXEL_MAP_S_TO_S stencil index stencil index 1 0
?GL_PIXEL_MAP_I_TO_R color index R 1 0
?GL_PIXEL_MAP_I_TO_G color index G 1 0
?GL_PIXEL_MAP_I_TO_B color index B 1 0
?GL_PIXEL_MAP_I_TO_A color index A 1 0
?GL_PIXEL_MAP_R_TO_R R R 1 0
?GL_PIXEL_MAP_G_TO_G G G 1 0
?GL_PIXEL_MAP_B_TO_B B B 1 0
?GL_PIXEL_MAP_A_TO_A A A 1 0
See external documentation.
pixelMapuiv(Map, Mapsize, Values) -> ok
Types:
Map = enum()
Mapsize = integer()
Values = binary()
See pixelMapfv/3
pixelMapusv(Map, Mapsize, Values) -> ok
Types:
Map = enum()
Mapsize = integer()
Values = binary()
See pixelMapfv/3
getPixelMapfv(Map, Values) -> ok
Types:
Map = enum()
Values = mem()
Return the specified pixel map
See the gl:pixelMapfv/3 reference page for a description of the acceptable values
for the Map parameter. gl:getPixelMap returns in Data the contents of the pixel map
specified in Map . Pixel maps are used during the execution of gl:readPixels/7 ,
gl:drawPixels/5 , gl:copyPixels/5 , gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 , gl:texSubImage1D/7 ,
gl:copyTexImage1D/7 , gl:copyTexImage2D/8 , gl:copyTexSubImage1D/6 ,
gl:copyTexSubImage2D/8 , and gl:copyTexSubImage3D/9 . to map color indices, stencil
indices, color components, and depth components to other values.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a pixel map is requested, Data is treated as a byte offset
into the buffer object's data store.
Unsigned integer values, if requested, are linearly mapped from the internal fixed
or floating-point representation such that 1.0 maps to the largest representable
integer value, and 0.0 maps to 0. Return unsigned integer values are undefined if
the map value was not in the range [0,1].
To determine the required size of Map , call gl:getBooleanv/1 with the appropriate
symbolic constant.
See external documentation.
getPixelMapuiv(Map, Values) -> ok
Types:
Map = enum()
Values = mem()
See getPixelMapfv/2
getPixelMapusv(Map, Values) -> ok
Types:
Map = enum()
Values = mem()
See getPixelMapfv/2
bitmap(Width, Height, Xorig, Yorig, Xmove, Ymove, Bitmap) -> ok
Types:
Width = integer()
Height = integer()
Xorig = float()
Yorig = float()
Xmove = float()
Ymove = float()
Bitmap = offset() | mem()
Draw a bitmap
A bitmap is a binary image. When drawn, the bitmap is positioned relative to the
current raster position, and frame buffer pixels corresponding to 1's in the bitmap
are written using the current raster color or index. Frame buffer pixels
corresponding to 0's in the bitmap are not modified.
gl:bitmap takes seven arguments. The first pair specifies the width and height of
the bitmap image. The second pair specifies the location of the bitmap origin
relative to the lower left corner of the bitmap image. The third pair of arguments
specifies x and y offsets to be added to the current raster position after the
bitmap has been drawn. The final argument is a pointer to the bitmap image itself.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a bitmap image is specified, Bitmap is treated as a
byte offset into the buffer object's data store.
The bitmap image is interpreted like image data for the gl:drawPixels/5 command,
with Width and Height corresponding to the width and height arguments of that
command, and with type set to ?GL_BITMAP and format set to ?GL_COLOR_INDEX . Modes
specified using gl:pixelStoref/2 affect the interpretation of bitmap image data;
modes specified using gl:pixelTransferf/2 do not.
If the current raster position is invalid, gl:bitmap is ignored. Otherwise, the
lower left corner of the bitmap image is positioned at the window coordinates
x w=|x r-x o|
y w=|y r-y o|
where (x r y r) is the raster position and (x o y o) is the bitmap origin.
Fragments are then generated for each pixel corresponding to a 1 (one) in the
bitmap image. These fragments are generated using the current raster z coordinate,
color or color index, and current raster texture coordinates. They are then treated
just as if they had been generated by a point, line, or polygon, including texture
mapping, fogging, and all per-fragment operations such as alpha and depth testing.
After the bitmap has been drawn, the x and y coordinates of the current raster
position are offset by Xmove and Ymove . No change is made to the z coordinate of
the current raster position, or to the current raster color, texture coordinates,
or index.
See external documentation.
readPixels(X, Y, Width, Height, Format, Type, Pixels) -> ok
Types:
X = integer()
Y = integer()
Width = integer()
Height = integer()
Format = enum()
Type = enum()
Pixels = mem()
Read a block of pixels from the frame buffer
gl:readPixels returns pixel data from the frame buffer, starting with the pixel
whose lower left corner is at location ( X , Y ), into client memory starting at
location Data . Several parameters control the processing of the pixel data before
it is placed into client memory. These parameters are set with gl:pixelStoref/2 .
This reference page describes the effects on gl:readPixels of most, but not all of
the parameters specified by these three commands.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a block of pixels is requested, Data is treated as a byte
offset into the buffer object's data store rather than a pointer to client memory.
gl:readPixels returns values from each pixel with lower left corner at (x+i y+j)
for 0<= i< width and 0<= j< height. This pixel is said to be the ith pixel in the
jth row. Pixels are returned in row order from the lowest to the highest row, left
to right in each row.
Format specifies the format for the returned pixel values; accepted values are:
?GL_STENCIL_INDEX: Stencil values are read from the stencil buffer. Each index is
converted to fixed point, shifted left or right depending on the value and sign of
?GL_INDEX_SHIFT , and added to ?GL_INDEX_OFFSET. If ?GL_MAP_STENCIL is ?GL_TRUE,
indices are replaced by their mappings in the table ?GL_PIXEL_MAP_S_TO_S.
?GL_DEPTH_COMPONENT: Depth values are read from the depth buffer. Each component is
converted to floating point such that the minimum depth value maps to 0 and the
maximum value maps to 1. Each component is then multiplied by ?GL_DEPTH_SCALE,
added to ?GL_DEPTH_BIAS , and finally clamped to the range [0 1].
?GL_DEPTH_STENCIL: Values are taken from both the depth and stencil buffers. The
Type parameter must be ?GL_UNSIGNED_INT_24_8 or ?GL_FLOAT_32_UNSIGNED_INT_24_8_REV
.
?GL_RED
?GL_GREEN
?GL_BLUE
?GL_RGB
?GL_BGR
?GL_RGBA
?GL_BGRA: Finally, the indices or components are converted to the proper format, as
specified by Type . If Format is ?GL_STENCIL_INDEX and Type is not ?GL_FLOAT, each
index is masked with the mask value given in the following table. If Type is
?GL_FLOAT, then each integer index is converted to single-precision floating-point
format.
If Format is ?GL_RED, ?GL_GREEN, ?GL_BLUE, ?GL_RGB, ?GL_BGR , ?GL_RGBA, or ?GL_BGRA
and Type is not ?GL_FLOAT, each component is multiplied by the multiplier shown in
the following table. If type is ?GL_FLOAT, then each component is passed as is (or
converted to the client's single-precision floating-point format if it is different
from the one used by the GL).TypeIndex MaskComponent Conversion
?GL_UNSIGNED_BYTE 2 8-1(2 8-1) c
?GL_BYTE 2 7-1((2 8-1) c-1)/2
?GL_UNSIGNED_SHORT 2 16-1(2 16-1) c
?GL_SHORT 2 15-1((2 16-1) c-1)/2
?GL_UNSIGNED_INT 2 32-1(2 32-1) c
?GL_INT 2 31-1((2 32-1) c-1)/2
?GL_HALF_FLOAT none c
?GL_FLOAT none c
?GL_UNSIGNED_BYTE_3_3_2 2 N-1(2 N-1) c
?GL_UNSIGNED_BYTE_2_3_3_REV 2 N-1(2 N-1) c
?GL_UNSIGNED_SHORT_5_6_5 2 N-1 (2 N-1) c
?GL_UNSIGNED_SHORT_5_6_5_REV 2 N-1(2 N-1) c
?GL_UNSIGNED_SHORT_4_4_4_4 2 N-1(2 N-1) c
?GL_UNSIGNED_SHORT_4_4_4_4_REV 2 N-1(2 N-1) c
?GL_UNSIGNED_SHORT_5_5_5_1 2 N-1(2 N-1) c
?GL_UNSIGNED_SHORT_1_5_5_5_REV 2 N-1 (2 N-1) c
?GL_UNSIGNED_INT_8_8_8_8 2 N-1(2 N-1) c
?GL_UNSIGNED_INT_8_8_8_8_REV 2 N-1(2 N-1) c
?GL_UNSIGNED_INT_10_10_10_2 2 N-1(2 N-1) c
?GL_UNSIGNED_INT_2_10_10_10_REV 2 N-1(2 N-1) c
?GL_UNSIGNED_INT_24_8 2 N-1(2 N-1) c
?GL_UNSIGNED_INT_10F_11F_11F_REV -- Special
?GL_UNSIGNED_INT_5_9_9_9_REV -- Special
?GL_FLOAT_32_UNSIGNED_INT_24_8_REV none c (Depth Only)
Return values are placed in memory as follows. If Format is ?GL_STENCIL_INDEX ,
?GL_DEPTH_COMPONENT, ?GL_RED, ?GL_GREEN, or ?GL_BLUE, a single value is returned
and the data for the ith pixel in the jth row is placed in location (j) width+i.
?GL_RGB and ?GL_BGR return three values, ?GL_RGBA and ?GL_BGRA return four values
for each pixel, with all values corresponding to a single pixel occupying
contiguous space in Data . Storage parameters set by gl:pixelStoref/2 , such as
?GL_PACK_LSB_FIRST and ?GL_PACK_SWAP_BYTES, affect the way that data is written
into memory. See gl:pixelStoref/2 for a description.
See external documentation.
drawPixels(Width, Height, Format, Type, Pixels) -> ok
Types:
Width = integer()
Height = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
Write a block of pixels to the frame buffer
gl:drawPixels reads pixel data from memory and writes it into the frame buffer
relative to the current raster position, provided that the raster position is
valid. Use gl:rasterPos2d/2 or gl:windowPos2d/2 to set the current raster position;
use gl:getBooleanv/1 with argument ?GL_CURRENT_RASTER_POSITION_VALID to determine
if the specified raster position is valid, and gl:getBooleanv/1 with argument
?GL_CURRENT_RASTER_POSITION to query the raster position.
Several parameters define the encoding of pixel data in memory and control the
processing of the pixel data before it is placed in the frame buffer. These
parameters are set with four commands: gl:pixelStoref/2 , gl:pixelTransferf/2 ,
gl:pixelMapfv/3 , and gl:pixelZoom/2 . This reference page describes the effects on
gl:drawPixels of many, but not all, of the parameters specified by these four
commands.
Data is read from Data as a sequence of signed or unsigned bytes, signed or
unsigned shorts, signed or unsigned integers, or single-precision floating-point
values, depending on Type . When Type is one of ?GL_UNSIGNED_BYTE, ?GL_BYTE,
?GL_UNSIGNED_SHORT , ?GL_SHORT, ?GL_UNSIGNED_INT, ?GL_INT, or ?GL_FLOAT each of
these bytes, shorts, integers, or floating-point values is interpreted as one color
or depth component, or one index, depending on Format . When Type is one of
?GL_UNSIGNED_BYTE_3_3_2 , ?GL_UNSIGNED_SHORT_5_6_5, ?GL_UNSIGNED_SHORT_4_4_4_4,
?GL_UNSIGNED_SHORT_5_5_5_1 , ?GL_UNSIGNED_INT_8_8_8_8, or
?GL_UNSIGNED_INT_10_10_10_2, each unsigned value is interpreted as containing all
the components for a single pixel, with the color components arranged according to
Format . When Type is one of ?GL_UNSIGNED_BYTE_2_3_3_REV ,
?GL_UNSIGNED_SHORT_5_6_5_REV, ?GL_UNSIGNED_SHORT_4_4_4_4_REV,
?GL_UNSIGNED_SHORT_1_5_5_5_REV , ?GL_UNSIGNED_INT_8_8_8_8_REV, or
?GL_UNSIGNED_INT_2_10_10_10_REV, each unsigned value is interpreted as containing
all color components, specified by Format , for a single pixel in a reversed order.
Indices are always treated individually. Color components are treated as groups of
one, two, three, or four values, again based on Format . Both individual indices
and groups of components are referred to as pixels. If Type is ?GL_BITMAP, the data
must be unsigned bytes, and Format must be either ?GL_COLOR_INDEX or
?GL_STENCIL_INDEX. Each unsigned byte is treated as eight 1-bit pixels, with bit
ordering determined by ?GL_UNPACK_LSB_FIRST (see gl:pixelStoref/2 ).
width×height pixels are read from memory, starting at location Data . By default,
these pixels are taken from adjacent memory locations, except that after all Width
pixels are read, the read pointer is advanced to the next four-byte boundary. The
four-byte row alignment is specified by gl:pixelStoref/2 with argument
?GL_UNPACK_ALIGNMENT , and it can be set to one, two, four, or eight bytes. Other
pixel store parameters specify different read pointer advancements, both before the
first pixel is read and after all Width pixels are read. See the gl:pixelStoref/2
reference page for details on these options.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a block of pixels is specified, Data is treated as a
byte offset into the buffer object's data store.
The width×height pixels that are read from memory are each operated on in the same
way, based on the values of several parameters specified by gl:pixelTransferf/2 and
gl:pixelMapfv/3 . The details of these operations, as well as the target buffer
into which the pixels are drawn, are specific to the format of the pixels, as
specified by Format . Format can assume one of 13 symbolic values:
?GL_COLOR_INDEX: Each pixel is a single value, a color index. It is converted to
fixed-point format, with an unspecified number of bits to the right of the binary
point, regardless of the memory data type. Floating-point values convert to true
fixed-point values. Signed and unsigned integer data is converted with all fraction
bits set to 0. Bitmap data convert to either 0 or 1.
Each fixed-point index is then shifted left by ?GL_INDEX_SHIFT bits and added to
?GL_INDEX_OFFSET . If ?GL_INDEX_SHIFT is negative, the shift is to the right. In
either case, zero bits fill otherwise unspecified bit locations in the result.
If the GL is in RGBA mode, the resulting index is converted to an RGBA pixel with
the help of the ?GL_PIXEL_MAP_I_TO_R, ?GL_PIXEL_MAP_I_TO_G, ?GL_PIXEL_MAP_I_TO_B ,
and ?GL_PIXEL_MAP_I_TO_A tables. If the GL is in color index mode, and if
?GL_MAP_COLOR is true, the index is replaced with the value that it references in
lookup table ?GL_PIXEL_MAP_I_TO_I . Whether the lookup replacement of the index is
done or not, the integer part of the index is then ANDed with 2 b-1, where b is the
number of bits in a color index buffer.
The GL then converts the resulting indices or RGBA colors to fragments by attaching
the current raster position z coordinate and texture coordinates to each pixel,
then assigning x and y window coordinates to the nth fragment such that x n=x r+n%
width
y n=y r+|n/width|
where (x r y r) is the current raster position. These pixel fragments are then
treated just like the fragments generated by rasterizing points, lines, or
polygons. Texture mapping, fog, and all the fragment operations are applied before
the fragments are written to the frame buffer.
?GL_STENCIL_INDEX: Each pixel is a single value, a stencil index. It is converted
to fixed-point format, with an unspecified number of bits to the right of the
binary point, regardless of the memory data type. Floating-point values convert to
true fixed-point values. Signed and unsigned integer data is converted with all
fraction bits set to 0. Bitmap data convert to either 0 or 1.
Each fixed-point index is then shifted left by ?GL_INDEX_SHIFT bits, and added to
?GL_INDEX_OFFSET. If ?GL_INDEX_SHIFT is negative, the shift is to the right. In
either case, zero bits fill otherwise unspecified bit locations in the result. If
?GL_MAP_STENCIL is true, the index is replaced with the value that it references in
lookup table ?GL_PIXEL_MAP_S_TO_S. Whether the lookup replacement of the index is
done or not, the integer part of the index is then ANDed with 2 b-1, where b is the
number of bits in the stencil buffer. The resulting stencil indices are then
written to the stencil buffer such that the nth index is written to location
x n=x r+n% width
y n=y r+|n/width|
where (x r y r) is the current raster position. Only the pixel ownership test, the
scissor test, and the stencil writemask affect these write operations.
?GL_DEPTH_COMPONENT: Each pixel is a single-depth component. Floating-point data is
converted directly to an internal floating-point format with unspecified precision.
Signed integer data is mapped linearly to the internal floating-point format such
that the most positive representable integer value maps to 1.0, and the most
negative representable value maps to -1.0. Unsigned integer data is mapped
similarly: the largest integer value maps to 1.0, and 0 maps to 0.0. The resulting
floating-point depth value is then multiplied by ?GL_DEPTH_SCALE and added to
?GL_DEPTH_BIAS. The result is clamped to the range [0 1].
The GL then converts the resulting depth components to fragments by attaching the
current raster position color or color index and texture coordinates to each pixel,
then assigning x and y window coordinates to the nth fragment such that
x n=x r+n% width
y n=y r+|n/width|
where (x r y r) is the current raster position. These pixel fragments are then
treated just like the fragments generated by rasterizing points, lines, or
polygons. Texture mapping, fog, and all the fragment operations are applied before
the fragments are written to the frame buffer.
?GL_RGBA
?GL_BGRA: Each pixel is a four-component group: For ?GL_RGBA, the red component is
first, followed by green, followed by blue, followed by alpha; for ?GL_BGRA the
order is blue, green, red and then alpha. Floating-point values are converted
directly to an internal floating-point format with unspecified precision. Signed
integer values are mapped linearly to the internal floating-point format such that
the most positive representable integer value maps to 1.0, and the most negative
representable value maps to -1.0. (Note that this mapping does not convert 0
precisely to 0.0.) Unsigned integer data is mapped similarly: The largest integer
value maps to 1.0, and 0 maps to 0.0. The resulting floating-point color values are
then multiplied by ?GL_c_SCALE and added to ?GL_c_BIAS, where c is RED, GREEN,
BLUE, and ALPHA for the respective color components. The results are clamped to the
range [0 1].
If ?GL_MAP_COLOR is true, each color component is scaled by the size of lookup
table ?GL_PIXEL_MAP_c_TO_c, then replaced by the value that it references in that
table. c is R, G, B, or A respectively.
The GL then converts the resulting RGBA colors to fragments by attaching the
current raster position z coordinate and texture coordinates to each pixel, then
assigning x and y window coordinates to the nth fragment such that
x n=x r+n% width
y n=y r+|n/width|
where (x r y r) is the current raster position. These pixel fragments are then
treated just like the fragments generated by rasterizing points, lines, or
polygons. Texture mapping, fog, and all the fragment operations are applied before
the fragments are written to the frame buffer.
?GL_RED: Each pixel is a single red component. This component is converted to the
internal floating-point format in the same way the red component of an RGBA pixel
is. It is then converted to an RGBA pixel with green and blue set to 0, and alpha
set to 1. After this conversion, the pixel is treated as if it had been read as an
RGBA pixel.
?GL_GREEN: Each pixel is a single green component. This component is converted to
the internal floating-point format in the same way the green component of an RGBA
pixel is. It is then converted to an RGBA pixel with red and blue set to 0, and
alpha set to 1. After this conversion, the pixel is treated as if it had been read
as an RGBA pixel.
?GL_BLUE: Each pixel is a single blue component. This component is converted to the
internal floating-point format in the same way the blue component of an RGBA pixel
is. It is then converted to an RGBA pixel with red and green set to 0, and alpha
set to 1. After this conversion, the pixel is treated as if it had been read as an
RGBA pixel.
?GL_ALPHA: Each pixel is a single alpha component. This component is converted to
the internal floating-point format in the same way the alpha component of an RGBA
pixel is. It is then converted to an RGBA pixel with red, green, and blue set to 0.
After this conversion, the pixel is treated as if it had been read as an RGBA
pixel.
?GL_RGB
?GL_BGR: Each pixel is a three-component group: red first, followed by green,
followed by blue; for ?GL_BGR, the first component is blue, followed by green and
then red. Each component is converted to the internal floating-point format in the
same way the red, green, and blue components of an RGBA pixel are. The color triple
is converted to an RGBA pixel with alpha set to 1. After this conversion, the pixel
is treated as if it had been read as an RGBA pixel.
?GL_LUMINANCE: Each pixel is a single luminance component. This component is
converted to the internal floating-point format in the same way the red component
of an RGBA pixel is. It is then converted to an RGBA pixel with red, green, and
blue set to the converted luminance value, and alpha set to 1. After this
conversion, the pixel is treated as if it had been read as an RGBA pixel.
?GL_LUMINANCE_ALPHA: Each pixel is a two-component group: luminance first, followed
by alpha. The two components are converted to the internal floating-point format in
the same way the red component of an RGBA pixel is. They are then converted to an
RGBA pixel with red, green, and blue set to the converted luminance value, and
alpha set to the converted alpha value. After this conversion, the pixel is treated
as if it had been read as an RGBA pixel.
The following table summarizes the meaning of the valid constants for the type
parameter:TypeCorresponding Type
?GL_UNSIGNED_BYTE unsigned 8-bit integer
?GL_BYTE signed 8-bit integer
?GL_BITMAP single bits in unsigned 8-bit integers
?GL_UNSIGNED_SHORT unsigned 16-bit integer
?GL_SHORT signed 16-bit integer
?GL_UNSIGNED_INT unsigned 32-bit integer
?GL_INT 32-bit integer
?GL_FLOAT single-precision floating-point
?GL_UNSIGNED_BYTE_3_3_2 unsigned 8-bit integer
?GL_UNSIGNED_BYTE_2_3_3_REV unsigned 8-bit integer with reversed component ordering
?GL_UNSIGNED_SHORT_5_6_5 unsigned 16-bit integer
?GL_UNSIGNED_SHORT_5_6_5_REV unsigned 16-bit integer with reversed component
ordering
?GL_UNSIGNED_SHORT_4_4_4_4 unsigned 16-bit integer
?GL_UNSIGNED_SHORT_4_4_4_4_REV unsigned 16-bit integer with reversed component
ordering
?GL_UNSIGNED_SHORT_5_5_5_1 unsigned 16-bit integer
?GL_UNSIGNED_SHORT_1_5_5_5_REV unsigned 16-bit integer with reversed component
ordering
?GL_UNSIGNED_INT_8_8_8_8 unsigned 32-bit integer
?GL_UNSIGNED_INT_8_8_8_8_REV unsigned 32-bit integer with reversed component
ordering
?GL_UNSIGNED_INT_10_10_10_2 unsigned 32-bit integer
?GL_UNSIGNED_INT_2_10_10_10_REV unsigned 32-bit integer with reversed component
ordering
The rasterization described so far assumes pixel zoom factors of 1. If
gl:pixelZoom/2 is used to change the x and y pixel zoom factors, pixels are
converted to fragments as follows. If (x r y r) is the current raster position, and
a given pixel is in the nth column and mth row of the pixel rectangle, then
fragments are generated for pixels whose centers are in the rectangle with corners
at
(x r+(zoom x) n y r+(zoom y) m)
(x r+(zoom x)(n+1) y r+(zoom y)(m+1))
where zoom x is the value of ?GL_ZOOM_X and zoom y is the value of ?GL_ZOOM_Y .
See external documentation.
copyPixels(X, Y, Width, Height, Type) -> ok
Types:
X = integer()
Y = integer()
Width = integer()
Height = integer()
Type = enum()
Copy pixels in the frame buffer
gl:copyPixels copies a screen-aligned rectangle of pixels from the specified frame
buffer location to a region relative to the current raster position. Its operation
is well defined only if the entire pixel source region is within the exposed
portion of the window. Results of copies from outside the window, or from regions
of the window that are not exposed, are hardware dependent and undefined.
X and Y specify the window coordinates of the lower left corner of the rectangular
region to be copied. Width and Height specify the dimensions of the rectangular
region to be copied. Both Width and Height must not be negative.
Several parameters control the processing of the pixel data while it is being
copied. These parameters are set with three commands: gl:pixelTransferf/2 ,
gl:pixelMapfv/3 , and gl:pixelZoom/2 . This reference page describes the effects on
gl:copyPixels of most, but not all, of the parameters specified by these three
commands.
gl:copyPixels copies values from each pixel with the lower left-hand corner at (x+i
y+j) for 0<= i< width and 0<= j< height. This pixel is said to be the ith pixel in
the jth row. Pixels are copied in row order from the lowest to the highest row,
left to right in each row.
Type specifies whether color, depth, or stencil data is to be copied. The details
of the transfer for each data type are as follows:
?GL_COLOR: Indices or RGBA colors are read from the buffer currently specified as
the read source buffer (see gl:readBuffer/1 ). If the GL is in color index mode,
each index that is read from this buffer is converted to a fixed-point format with
an unspecified number of bits to the right of the binary point. Each index is then
shifted left by ?GL_INDEX_SHIFT bits, and added to ?GL_INDEX_OFFSET. If
?GL_INDEX_SHIFT is negative, the shift is to the right. In either case, zero bits
fill otherwise unspecified bit locations in the result. If ?GL_MAP_COLOR is true,
the index is replaced with the value that it references in lookup table
?GL_PIXEL_MAP_I_TO_I. Whether the lookup replacement of the index is done or not,
the integer part of the index is then ANDed with 2 b-1, where b is the number of
bits in a color index buffer.
If the GL is in RGBA mode, the red, green, blue, and alpha components of each pixel
that is read are converted to an internal floating-point format with unspecified
precision. The conversion maps the largest representable component value to 1.0,
and component value 0 to 0.0. The resulting floating-point color values are then
multiplied by ?GL_c_SCALE and added to ?GL_c_BIAS, where c is RED, GREEN, BLUE, and
ALPHA for the respective color components. The results are clamped to the range
[0,1]. If ?GL_MAP_COLOR is true, each color component is scaled by the size of
lookup table ?GL_PIXEL_MAP_c_TO_c , then replaced by the value that it references
in that table. c is R, G, B, or A.
If the ARB_imaging extension is supported, the color values may be additionally
processed by color-table lookups, color-matrix transformations, and convolution
filters.
The GL then converts the resulting indices or RGBA colors to fragments by attaching
the current raster position z coordinate and texture coordinates to each pixel,
then assigning window coordinates (x r+i y r+j), where (x r y r) is the current
raster position, and the pixel was the ith pixel in the jth row. These pixel
fragments are then treated just like the fragments generated by rasterizing points,
lines, or polygons. Texture mapping, fog, and all the fragment operations are
applied before the fragments are written to the frame buffer.
?GL_DEPTH: Depth values are read from the depth buffer and converted directly to an
internal floating-point format with unspecified precision. The resulting floating-
point depth value is then multiplied by ?GL_DEPTH_SCALE and added to ?GL_DEPTH_BIAS
. The result is clamped to the range [0,1].
The GL then converts the resulting depth components to fragments by attaching the
current raster position color or color index and texture coordinates to each pixel,
then assigning window coordinates (x r+i y r+j), where (x r y r) is the current
raster position, and the pixel was the ith pixel in the jth row. These pixel
fragments are then treated just like the fragments generated by rasterizing points,
lines, or polygons. Texture mapping, fog, and all the fragment operations are
applied before the fragments are written to the frame buffer.
?GL_STENCIL: Stencil indices are read from the stencil buffer and converted to an
internal fixed-point format with an unspecified number of bits to the right of the
binary point. Each fixed-point index is then shifted left by ?GL_INDEX_SHIFT bits,
and added to ?GL_INDEX_OFFSET. If ?GL_INDEX_SHIFT is negative, the shift is to the
right. In either case, zero bits fill otherwise unspecified bit locations in the
result. If ?GL_MAP_STENCIL is true, the index is replaced with the value that it
references in lookup table ?GL_PIXEL_MAP_S_TO_S. Whether the lookup replacement of
the index is done or not, the integer part of the index is then ANDed with 2 b-1,
where b is the number of bits in the stencil buffer. The resulting stencil indices
are then written to the stencil buffer such that the index read from the ith
location of the jth row is written to location (x r+i y r+j), where (x r y r) is
the current raster position. Only the pixel ownership test, the scissor test, and
the stencil writemask affect these write operations.
The rasterization described thus far assumes pixel zoom factors of 1.0. If
gl:pixelZoom/2 is used to change the x and y pixel zoom factors, pixels are
converted to fragments as follows. If (x r y r) is the current raster position, and
a given pixel is in the ith location in the jth row of the source pixel rectangle,
then fragments are generated for pixels whose centers are in the rectangle with
corners at
(x r+(zoom x) i y r+(zoom y) j)
and
(x r+(zoom x)(i+1) y r+(zoom y)(j+1))
where zoom x is the value of ?GL_ZOOM_X and zoom y is the value of ?GL_ZOOM_Y .
See external documentation.
stencilFunc(Func, Ref, Mask) -> ok
Types:
Func = enum()
Ref = integer()
Mask = integer()
Set front and back function and reference value for stencil testing
Stenciling, like depth-buffering, enables and disables drawing on a per-pixel
basis. Stencil planes are first drawn into using GL drawing primitives, then
geometry and images are rendered using the stencil planes to mask out portions of
the screen. Stenciling is typically used in multipass rendering algorithms to
achieve special effects, such as decals, outlining, and constructive solid geometry
rendering.
The stencil test conditionally eliminates a pixel based on the outcome of a
comparison between the reference value and the value in the stencil buffer. To
enable and disable the test, call gl:enable/1 and gl:enable/1 with argument
?GL_STENCIL_TEST . To specify actions based on the outcome of the stencil test,
call gl:stencilOp/3 or gl:stencilOpSeparate/4 .
There can be two separate sets of Func , Ref , and Mask parameters; one affects
back-facing polygons, and the other affects front-facing polygons as well as other
non-polygon primitives. gl:stencilFunc/3 sets both front and back stencil state to
the same values. Use gl:stencilFuncSeparate/4 to set front and back stencil state
to different values.
Func is a symbolic constant that determines the stencil comparison function. It
accepts one of eight values, shown in the following list. Ref is an integer
reference value that is used in the stencil comparison. It is clamped to the range
[0 2 n-1], where n is the number of bitplanes in the stencil buffer. Mask is
bitwise ANDed with both the reference value and the stored stencil value, with the
ANDed values participating in the comparison.
If stencil represents the value stored in the corresponding stencil buffer
location, the following list shows the effect of each comparison function that can
be specified by Func . Only if the comparison succeeds is the pixel passed through
to the next stage in the rasterization process (see gl:stencilOp/3 ). All tests
treat stencil values as unsigned integers in the range [0 2 n-1], where n is the
number of bitplanes in the stencil buffer.
The following values are accepted by Func :
?GL_NEVER: Always fails.
?GL_LESS: Passes if ( Ref & Mask ) < ( stencil & Mask ).
?GL_LEQUAL: Passes if ( Ref & Mask ) <= ( stencil & Mask ).
?GL_GREATER: Passes if ( Ref & Mask ) > ( stencil & Mask ).
?GL_GEQUAL: Passes if ( Ref & Mask ) >= ( stencil & Mask ).
?GL_EQUAL: Passes if ( Ref & Mask ) = ( stencil & Mask ).
?GL_NOTEQUAL: Passes if ( Ref & Mask ) != ( stencil & Mask ).
?GL_ALWAYS: Always passes.
See external documentation.
stencilMask(Mask) -> ok
Types:
Mask = integer()
Control the front and back writing of individual bits in the stencil planes
gl:stencilMask controls the writing of individual bits in the stencil planes. The
least significant n bits of Mask , where n is the number of bits in the stencil
buffer, specify a mask. Where a 1 appears in the mask, it's possible to write to
the corresponding bit in the stencil buffer. Where a 0 appears, the corresponding
bit is write-protected. Initially, all bits are enabled for writing.
There can be two separate Mask writemasks; one affects back-facing polygons, and
the other affects front-facing polygons as well as other non-polygon primitives.
gl:stencilMask/1 sets both front and back stencil writemasks to the same values.
Use gl:stencilMaskSeparate/2 to set front and back stencil writemasks to different
values.
See external documentation.
stencilOp(Fail, Zfail, Zpass) -> ok
Types:
Fail = enum()
Zfail = enum()
Zpass = enum()
Set front and back stencil test actions
Stenciling, like depth-buffering, enables and disables drawing on a per-pixel
basis. You draw into the stencil planes using GL drawing primitives, then render
geometry and images, using the stencil planes to mask out portions of the screen.
Stenciling is typically used in multipass rendering algorithms to achieve special
effects, such as decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome of a
comparison between the value in the stencil buffer and a reference value. To enable
and disable the test, call gl:enable/1 and gl:enable/1 with argument
?GL_STENCIL_TEST ; to control it, call gl:stencilFunc/3 or gl:stencilFuncSeparate/4
.
There can be two separate sets of Sfail , Dpfail , and Dppass parameters; one
affects back-facing polygons, and the other affects front-facing polygons as well
as other non-polygon primitives. gl:stencilOp/3 sets both front and back stencil
state to the same values. Use gl:stencilOpSeparate/4 to set front and back stencil
state to different values.
gl:stencilOp takes three arguments that indicate what happens to the stored stencil
value while stenciling is enabled. If the stencil test fails, no change is made to
the pixel's color or depth buffers, and Sfail specifies what happens to the stencil
buffer contents. The following eight actions are possible.
?GL_KEEP: Keeps the current value.
?GL_ZERO: Sets the stencil buffer value to 0.
?GL_REPLACE: Sets the stencil buffer value to ref, as specified by gl:stencilFunc/3
.
?GL_INCR: Increments the current stencil buffer value. Clamps to the maximum
representable unsigned value.
?GL_INCR_WRAP: Increments the current stencil buffer value. Wraps stencil buffer
value to zero when incrementing the maximum representable unsigned value.
?GL_DECR: Decrements the current stencil buffer value. Clamps to 0.
?GL_DECR_WRAP: Decrements the current stencil buffer value. Wraps stencil buffer
value to the maximum representable unsigned value when decrementing a stencil
buffer value of zero.
?GL_INVERT: Bitwise inverts the current stencil buffer value.
Stencil buffer values are treated as unsigned integers. When incremented and
decremented, values are clamped to 0 and 2 n-1, where n is the value returned by
querying ?GL_STENCIL_BITS .
The other two arguments to gl:stencilOp specify stencil buffer actions that depend
on whether subsequent depth buffer tests succeed ( Dppass ) or fail ( Dpfail ) (see
gl:depthFunc/1 ). The actions are specified using the same eight symbolic constants
as Sfail . Note that Dpfail is ignored when there is no depth buffer, or when the
depth buffer is not enabled. In these cases, Sfail and Dppass specify stencil
action when the stencil test fails and passes, respectively.
See external documentation.
clearStencil(S) -> ok
Types:
S = integer()
Specify the clear value for the stencil buffer
gl:clearStencil specifies the index used by gl:clear/1 to clear the stencil buffer.
S is masked with 2 m-1, where m is the number of bits in the stencil buffer.
See external documentation.
texGend(Coord, Pname, Param) -> ok
Types:
Coord = enum()
Pname = enum()
Param = float()
Control the generation of texture coordinates
gl:texGen selects a texture-coordinate generation function or supplies coefficients
for one of the functions. Coord names one of the (s, t, r, q ) texture coordinates;
it must be one of the symbols ?GL_S, ?GL_T, ?GL_R , or ?GL_Q. Pname must be one of
three symbolic constants: ?GL_TEXTURE_GEN_MODE , ?GL_OBJECT_PLANE, or
?GL_EYE_PLANE. If Pname is ?GL_TEXTURE_GEN_MODE , then Params chooses a mode, one
of ?GL_OBJECT_LINEAR, ?GL_EYE_LINEAR , ?GL_SPHERE_MAP, ?GL_NORMAL_MAP, or
?GL_REFLECTION_MAP. If Pname is either ?GL_OBJECT_PLANE or ?GL_EYE_PLANE, Params
contains coefficients for the corresponding texture generation function.
If the texture generation function is ?GL_OBJECT_LINEAR, the function
g=p 1×x o+p 2×y o+p 3×z o+p 4×w o
is used, where g is the value computed for the coordinate named in Coord , p 1, p
2, p 3, and p 4 are the four values supplied in Params , and x o, y o, z o, and w o
are the object coordinates of the vertex. This function can be used, for example,
to texture-map terrain using sea level as a reference plane (defined by p 1, p 2, p
3, and p 4). The altitude of a terrain vertex is computed by the ?GL_OBJECT_LINEAR
coordinate generation function as its distance from sea level; that altitude can
then be used to index the texture image to map white snow onto peaks and green
grass onto foothills.
If the texture generation function is ?GL_EYE_LINEAR, the function
g=(p 1)"×x e+(p 2)"×y e+(p 3)"×z e+(p 4)"×w e
is used, where
((p 1)" (p 2)" (p 3)" (p 4)")=(p 1 p 2 p 3 p 4) M -1
and x e, y e, z e, and w e are the eye coordinates of the vertex, p 1, p 2, p 3,
and p 4 are the values supplied in Params , and M is the modelview matrix when
gl:texGen is invoked. If M is poorly conditioned or singular, texture coordinates
generated by the resulting function may be inaccurate or undefined.
Note that the values in Params define a reference plane in eye coordinates. The
modelview matrix that is applied to them may not be the same one in effect when the
polygon vertices are transformed. This function establishes a field of texture
coordinates that can produce dynamic contour lines on moving objects.
If the texture generation function is ?GL_SPHERE_MAP and Coord is either ?GL_S or
?GL_T, s and t texture coordinates are generated as follows. Let u be the unit
vector pointing from the origin to the polygon vertex (in eye coordinates). Let n
sup prime be the current normal, after transformation to eye coordinates. Let
f=(f x f y f z) T be the reflection vector such that
f=u-2 n" (n") T u
Finally, let m=2 ((f x) 2+(f y) 2+(f z+1) 2). Then the values assigned to the s and
t texture coordinates are
s=f x/m+1/2
t=f y/m+1/2
To enable or disable a texture-coordinate generation function, call gl:enable/1 or
gl:enable/1 with one of the symbolic texture-coordinate names (?GL_TEXTURE_GEN_S ,
?GL_TEXTURE_GEN_T, ?GL_TEXTURE_GEN_R, or ?GL_TEXTURE_GEN_Q) as the argument. When
enabled, the specified texture coordinate is computed according to the generating
function associated with that coordinate. When disabled, subsequent vertices take
the specified texture coordinate from the current set of texture coordinates.
Initially, all texture generation functions are set to ?GL_EYE_LINEAR and are
disabled. Both s plane equations are (1, 0, 0, 0), both t plane equations are (0,
1, 0, 0), and all r and q plane equations are (0, 0, 0, 0).
When the ARB_multitexture extension is supported, gl:texGen sets the texture
generation parameters for the currently active texture unit, selected with
gl:activeTexture/1 .
See external documentation.
texGenf(Coord, Pname, Param) -> ok
Types:
Coord = enum()
Pname = enum()
Param = float()
See texGend/3
texGeni(Coord, Pname, Param) -> ok
Types:
Coord = enum()
Pname = enum()
Param = integer()
See texGend/3
texGendv(Coord, Pname, Params) -> ok
Types:
Coord = enum()
Pname = enum()
Params = {float()}
See texGend/3
texGenfv(Coord, Pname, Params) -> ok
Types:
Coord = enum()
Pname = enum()
Params = {float()}
See texGend/3
texGeniv(Coord, Pname, Params) -> ok
Types:
Coord = enum()
Pname = enum()
Params = {integer()}
See texGend/3
getTexGendv(Coord, Pname) -> {float(), float(), float(), float()}
Types:
Coord = enum()
Pname = enum()
Return texture coordinate generation parameters
gl:getTexGen returns in Params selected parameters of a texture coordinate
generation function that was specified using gl:texGend/3 . Coord names one of the
(s, t, r, q) texture coordinates, using the symbolic constant ?GL_S, ?GL_T, ?GL_R,
or ?GL_Q.
Pname specifies one of three symbolic names:
?GL_TEXTURE_GEN_MODE: Params returns the single-valued texture generation function,
a symbolic constant. The initial value is ?GL_EYE_LINEAR.
?GL_OBJECT_PLANE: Params returns the four plane equation coefficients that specify
object linear-coordinate generation. Integer values, when requested, are mapped
directly from the internal floating-point representation.
?GL_EYE_PLANE: Params returns the four plane equation coefficients that specify eye
linear-coordinate generation. Integer values, when requested, are mapped directly
from the internal floating-point representation. The returned values are those
maintained in eye coordinates. They are not equal to the values specified using
gl:texGend/3 , unless the modelview matrix was identity when gl:texGend/3 was
called.
See external documentation.
getTexGenfv(Coord, Pname) -> {float(), float(), float(), float()}
Types:
Coord = enum()
Pname = enum()
See getTexGendv/2
getTexGeniv(Coord, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Coord = enum()
Pname = enum()
See getTexGendv/2
texEnvf(Target, Pname, Param) -> ok
Types:
Target = enum()
Pname = enum()
Param = float()
glTexEnvf
See external documentation.
texEnvi(Target, Pname, Param) -> ok
Types:
Target = enum()
Pname = enum()
Param = integer()
glTexEnvi
See external documentation.
texEnvfv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {float()}
Set texture environment parameters
A texture environment specifies how texture values are interpreted when a fragment
is textured. When Target is ?GL_TEXTURE_FILTER_CONTROL, Pname must be
?GL_TEXTURE_LOD_BIAS . When Target is ?GL_TEXTURE_ENV, Pname can be
?GL_TEXTURE_ENV_MODE , ?GL_TEXTURE_ENV_COLOR, ?GL_COMBINE_RGB, ?GL_COMBINE_ALPHA,
?GL_RGB_SCALE , ?GL_ALPHA_SCALE, ?GL_SRC0_RGB, ?GL_SRC1_RGB, ?GL_SRC2_RGB,
?GL_SRC0_ALPHA , ?GL_SRC1_ALPHA, or ?GL_SRC2_ALPHA.
If Pname is ?GL_TEXTURE_ENV_MODE, then Params is (or points to) the symbolic name
of a texture function. Six texture functions may be specified: ?GL_ADD ,
?GL_MODULATE, ?GL_DECAL, ?GL_BLEND, ?GL_REPLACE, or ?GL_COMBINE .
The following table shows the correspondence of filtered texture values R t, G t, B
t, A t, L t, I t to texture source components. C s and A s are used by the texture
functions described below. Texture Base Internal Format C s A s
?GL_ALPHA (0, 0, 0) A t
?GL_LUMINANCE ( L t, L t, L t ) 1
?GL_LUMINANCE_ALPHA ( L t, L t, L t ) A t
?GL_INTENSITY ( I t, I t, I t ) I t
?GL_RGB ( R t, G t, B t ) 1
?GL_RGBA ( R t, G t, B t ) A t
A texture function acts on the fragment to be textured using the texture image
value that applies to the fragment (see gl:texParameterf/3 ) and produces an RGBA
color for that fragment. The following table shows how the RGBA color is produced
for each of the first five texture functions that can be chosen. C is a triple of
color values (RGB) and A is the associated alpha value. RGBA values extracted from
a texture image are in the range [0,1]. The subscript p refers to the color
computed from the previous texture stage (or the incoming fragment if processing
texture stage 0), the subscript s to the texture source color, the subscript c to
the texture environment color, and the subscript v indicates a value produced by
the texture function. Texture Base Internal Format ?Value?GL_REPLACE Function
?GL_MODULATE Function ?GL_DECAL Function ?GL_BLEND Function ?GL_ADD Function
?GL_ALPHA C v= C p C p undefined C p C p
A v= A s A p A s A v=A p A s A p A s
?GL_LUMINANCE C v= C s C p C s undefined C p (1-C s)+C c C s C p+C s
(or 1) A v= A p A p A p A p
?GL_LUMINANCE_ALPHA C v= C s C p C s undefined C p (1-C s)+C c C s C p+C s
(or 2) A v= A s A p A s A p A s A p A s
?GL_INTENSITY C v= C s C p C s undefined C p (1-C s)+C c C s C p+C s
A v= A s A p A s A p (1-A s)+A c A s A p+A s
?GL_RGB C v= C s C p C s C s C p (1-C s)+C c C s C p+C s
(or 3) A v= A p A p A p A p A p
?GL_RGBA C v= C s C p C s C p (1-A s)+C s A s C p (1-C s)+C c C s C p+C s
(or 4) A v= A s A p A s A p A p A s A p A s
If Pname is ?GL_TEXTURE_ENV_MODE, and Params is ?GL_COMBINE, the form of the
texture function depends on the values of ?GL_COMBINE_RGB and ?GL_COMBINE_ALPHA .
The following describes how the texture sources, as specified by ?GL_SRC0_RGB,
?GL_SRC1_RGB , ?GL_SRC2_RGB, ?GL_SRC0_ALPHA, ?GL_SRC1_ALPHA, and ?GL_SRC2_ALPHA ,
are combined to produce a final texture color. In the following tables, ?GL_SRC0_c
is represented by Arg0, ?GL_SRC1_c is represented by Arg1, and ?GL_SRC2_c is
represented by Arg2.
?GL_COMBINE_RGB accepts any of ?GL_REPLACE, ?GL_MODULATE, ?GL_ADD , ?GL_ADD_SIGNED,
?GL_INTERPOLATE, ?GL_SUBTRACT, ?GL_DOT3_RGB, or
?GL_DOT3_RGBA.?GL_COMBINE_RGBTexture Function
?GL_REPLACE Arg0
?GL_MODULATE Arg0×Arg1
?GL_ADD Arg0+Arg1
?GL_ADD_SIGNED Arg0+Arg1-0.5
?GL_INTERPOLATE Arg0×Arg2+Arg1×(1- Arg2)
?GL_SUBTRACT Arg0-Arg1
?GL_DOT3_RGB or ?GL_DOT3_RGBA 4×((((Arg0 r)-0.5)×((Arg1 r)-0.5))+(((Arg0
g)-0.5)×((Arg1 g)-0.5))+(((Arg0 b)-0.5)×((Arg1 b)-0.5)))
The scalar results for ?GL_DOT3_RGB and ?GL_DOT3_RGBA are placed into each of the 3
(RGB) or 4 (RGBA) components on output.
Likewise, ?GL_COMBINE_ALPHA accepts any of ?GL_REPLACE, ?GL_MODULATE, ?GL_ADD,
?GL_ADD_SIGNED, ?GL_INTERPOLATE, or ?GL_SUBTRACT. The following table describes how
alpha values are combined:?GL_COMBINE_ALPHATexture Function
?GL_REPLACE Arg0
?GL_MODULATE Arg0×Arg1
?GL_ADD Arg0+Arg1
?GL_ADD_SIGNED Arg0+Arg1-0.5
?GL_INTERPOLATE Arg0×Arg2+Arg1×(1- Arg2)
?GL_SUBTRACT Arg0-Arg1
In the following tables, the value C s represents the color sampled from the
currently bound texture, C c represents the constant texture-environment color, C f
represents the primary color of the incoming fragment, and C p represents the color
computed from the previous texture stage or C f if processing texture stage 0.
Likewise, A s, A c, A f, and A p represent the respective alpha values.
The following table describes the values assigned to Arg0, Arg1, and Arg2 based
upon the RGB sources and operands:?GL_SRCn_RGB?GL_OPERANDn_RGBArgument Value
?GL_TEXTURE?GL_SRC_COLOR(C s)
?GL_ONE_MINUS_SRC_COLOR 1-(C s)
?GL_SRC_ALPHA(A s)
?GL_ONE_MINUS_SRC_ALPHA 1-(A s)
?GL_TEXTUREn?GL_SRC_COLOR(C s)
?GL_ONE_MINUS_SRC_COLOR 1-(C s)
?GL_SRC_ALPHA (A s)
?GL_ONE_MINUS_SRC_ALPHA 1-(A s)
?GL_CONSTANT?GL_SRC_COLOR(C c)
?GL_ONE_MINUS_SRC_COLOR 1-(C c)
?GL_SRC_ALPHA(A c)
?GL_ONE_MINUS_SRC_ALPHA 1-(A c)
?GL_PRIMARY_COLOR?GL_SRC_COLOR(C f)
?GL_ONE_MINUS_SRC_COLOR 1-(C f)
?GL_SRC_ALPHA(A f)
?GL_ONE_MINUS_SRC_ALPHA 1-(A f)
?GL_PREVIOUS?GL_SRC_COLOR (C p)
?GL_ONE_MINUS_SRC_COLOR 1-(C p)
?GL_SRC_ALPHA(A p)
?GL_ONE_MINUS_SRC_ALPHA 1-(A p)
For ?GL_TEXTUREn sources, C s and A s represent the color and alpha, respectively,
produced from texture stage n.
The follow table describes the values assigned to Arg0, Arg1, and Arg2 based upon
the alpha sources and operands:?GL_SRCn_ALPHA?GL_OPERANDn_ALPHAArgument Value
?GL_TEXTURE?GL_SRC_ALPHA(A s)
?GL_ONE_MINUS_SRC_ALPHA 1-(A s)
?GL_TEXTUREn?GL_SRC_ALPHA(A s)
?GL_ONE_MINUS_SRC_ALPHA 1-(A s)
?GL_CONSTANT?GL_SRC_ALPHA(A c)
?GL_ONE_MINUS_SRC_ALPHA 1-(A c)
?GL_PRIMARY_COLOR?GL_SRC_ALPHA(A f)
?GL_ONE_MINUS_SRC_ALPHA 1-(A f)
?GL_PREVIOUS?GL_SRC_ALPHA(A p)
?GL_ONE_MINUS_SRC_ALPHA 1-(A p)
The RGB and alpha results of the texture function are multipled by the values of
?GL_RGB_SCALE and ?GL_ALPHA_SCALE, respectively, and clamped to the range [0 1].
If Pname is ?GL_TEXTURE_ENV_COLOR, Params is a pointer to an array that holds an
RGBA color consisting of four values. Integer color components are interpreted
linearly such that the most positive integer maps to 1.0, and the most negative
integer maps to -1.0. The values are clamped to the range [0,1] when they are
specified. C c takes these four values.
If Pname is ?GL_TEXTURE_LOD_BIAS, the value specified is added to the texture
level-of-detail parameter, that selects which mipmap, or mipmaps depending upon the
selected ?GL_TEXTURE_MIN_FILTER, will be sampled.
?GL_TEXTURE_ENV_MODE defaults to ?GL_MODULATE and ?GL_TEXTURE_ENV_COLOR defaults to
(0, 0, 0, 0).
If Target is ?GL_POINT_SPRITE and Pname is ?GL_COORD_REPLACE, the boolean value
specified is used to either enable or disable point sprite texture coordinate
replacement. The default value is ?GL_FALSE.
See external documentation.
texEnviv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer()}
See texEnvfv/3
getTexEnvfv(Target, Pname) -> {float(), float(), float(), float()}
Types:
Target = enum()
Pname = enum()
Return texture environment parameters
gl:getTexEnv returns in Params selected values of a texture environment that was
specified with gl:texEnvfv/3 . Target specifies a texture environment.
When Target is ?GL_TEXTURE_FILTER_CONTROL, Pname must be ?GL_TEXTURE_LOD_BIAS .
When Target is ?GL_POINT_SPRITE, Pname must be ?GL_COORD_REPLACE . When Target is
?GL_TEXTURE_ENV, Pname can be ?GL_TEXTURE_ENV_MODE , ?GL_TEXTURE_ENV_COLOR,
?GL_COMBINE_RGB, ?GL_COMBINE_ALPHA, ?GL_RGB_SCALE , ?GL_ALPHA_SCALE, ?GL_SRC0_RGB,
?GL_SRC1_RGB, ?GL_SRC2_RGB, ?GL_SRC0_ALPHA, ?GL_SRC1_ALPHA, or ?GL_SRC2_ALPHA.
Pname names a specific texture environment parameter, as follows:
?GL_TEXTURE_ENV_MODE: Params returns the single-valued texture environment mode, a
symbolic constant. The initial value is ?GL_MODULATE.
?GL_TEXTURE_ENV_COLOR: Params returns four integer or floating-point values that
are the texture environment color. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0 maps to the
most positive representable integer, and -1.0 maps to the most negative
representable integer. The initial value is (0, 0, 0, 0).
?GL_TEXTURE_LOD_BIAS: Params returns a single floating-point value that is the
texture level-of-detail bias. The initial value is 0.
?GL_COMBINE_RGB: Params returns a single symbolic constant value representing the
current RGB combine mode. The initial value is ?GL_MODULATE.
?GL_COMBINE_ALPHA: Params returns a single symbolic constant value representing the
current alpha combine mode. The initial value is ?GL_MODULATE.
?GL_SRC0_RGB: Params returns a single symbolic constant value representing the
texture combiner zero's RGB source. The initial value is ?GL_TEXTURE.
?GL_SRC1_RGB: Params returns a single symbolic constant value representing the
texture combiner one's RGB source. The initial value is ?GL_PREVIOUS.
?GL_SRC2_RGB: Params returns a single symbolic constant value representing the
texture combiner two's RGB source. The initial value is ?GL_CONSTANT.
?GL_SRC0_ALPHA: Params returns a single symbolic constant value representing the
texture combiner zero's alpha source. The initial value is ?GL_TEXTURE.
?GL_SRC1_ALPHA: Params returns a single symbolic constant value representing the
texture combiner one's alpha source. The initial value is ?GL_PREVIOUS.
?GL_SRC2_ALPHA: Params returns a single symbolic constant value representing the
texture combiner two's alpha source. The initial value is ?GL_CONSTANT.
?GL_OPERAND0_RGB: Params returns a single symbolic constant value representing the
texture combiner zero's RGB operand. The initial value is ?GL_SRC_COLOR.
?GL_OPERAND1_RGB: Params returns a single symbolic constant value representing the
texture combiner one's RGB operand. The initial value is ?GL_SRC_COLOR.
?GL_OPERAND2_RGB: Params returns a single symbolic constant value representing the
texture combiner two's RGB operand. The initial value is ?GL_SRC_ALPHA.
?GL_OPERAND0_ALPHA: Params returns a single symbolic constant value representing
the texture combiner zero's alpha operand. The initial value is ?GL_SRC_ALPHA.
?GL_OPERAND1_ALPHA: Params returns a single symbolic constant value representing
the texture combiner one's alpha operand. The initial value is ?GL_SRC_ALPHA.
?GL_OPERAND2_ALPHA: Params returns a single symbolic constant value representing
the texture combiner two's alpha operand. The initial value is ?GL_SRC_ALPHA.
?GL_RGB_SCALE: Params returns a single floating-point value representing the
current RGB texture combiner scaling factor. The initial value is 1.0.
?GL_ALPHA_SCALE: Params returns a single floating-point value representing the
current alpha texture combiner scaling factor. The initial value is 1.0.
?GL_COORD_REPLACE: Params returns a single boolean value representing the current
point sprite texture coordinate replacement enable state. The initial value is
?GL_FALSE .
See external documentation.
getTexEnviv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
See getTexEnvfv/2
texParameterf(Target, Pname, Param) -> ok
Types:
Target = enum()
Pname = enum()
Param = float()
Set texture parameters
gl:texParameter assigns the value or values in Params to the texture parameter
specified as Pname . Target defines the target texture, either ?GL_TEXTURE_1D ,
?GL_TEXTURE_2D, ?GL_TEXTURE_1D_ARRAY, ?GL_TEXTURE_2D_ARRAY, ?GL_TEXTURE_RECTANGLE ,
or ?GL_TEXTURE_3D. The following symbols are accepted in Pname :
?GL_TEXTURE_BASE_LEVEL: Specifies the index of the lowest defined mipmap level.
This is an integer value. The initial value is 0.
?GL_TEXTURE_BORDER_COLOR: The data in Params specifies four values that define the
border values that should be used for border texels. If a texel is sampled from the
border of the texture, the values of ?GL_TEXTURE_BORDER_COLOR are interpreted as an
RGBA color to match the texture's internal format and substituted for the non-
existent texel data. If the texture contains depth components, the first component
of ?GL_TEXTURE_BORDER_COLOR is interpreted as a depth value. The initial value is (
0.0, 0.0, 0.0, 0.0 ).
If the values for ?GL_TEXTURE_BORDER_COLOR are specified with gl:texParameterIiv or
gl:texParameterIuiv, the values are stored unmodified with an internal data type of
integer. If specified with gl:texParameteriv, they are converted to floating point
with the following equation: f=2 c+1 2 b-/1. If specified with gl:texParameterfv ,
they are stored unmodified as floating-point values.
?GL_TEXTURE_COMPARE_FUNC: Specifies the comparison operator used when
?GL_TEXTURE_COMPARE_MODE is set to ?GL_COMPARE_REF_TO_TEXTURE. Permissible values
are:Texture Comparison FunctionComputed result
?GL_LEQUAL result={1.0 0.0 r<=(D t) r>(D t))
?GL_GEQUAL result={1.0 0.0 r>=(D t) r<(D t))
?GL_LESS result={1.0 0.0 r<(D t) r>=(D t))
?GL_GREATER result={1.0 0.0 r>(D t) r<=(D t))
?GL_EQUAL result={1.0 0.0 r=(D t) r≠ (D t))
?GL_NOTEQUAL result={1.0 0.0 r≠(D t) r=(D t))
?GL_ALWAYS result=1.0
?GL_NEVER result=0.0
where r is the current interpolated texture coordinate, and D t is the depth
texture value sampled from the currently bound depth texture. result is assigned to
the the red channel.
?GL_TEXTURE_COMPARE_MODE: Specifies the texture comparison mode for currently bound
depth textures. That is, a texture whose internal format is ?GL_DEPTH_COMPONENT_* ;
see gl:texImage2D/9 ) Permissible values are:
?GL_COMPARE_REF_TO_TEXTURE: Specifies that the interpolated and clamped r texture
coordinate should be compared to the value in the currently bound depth texture.
See the discussion of ?GL_TEXTURE_COMPARE_FUNC for details of how the comparison is
evaluated. The result of the comparison is assigned to the red channel.
?GL_NONE: Specifies that the red channel should be assigned the appropriate value
from the currently bound depth texture.
?GL_TEXTURE_LOD_BIAS: Params specifies a fixed bias value that is to be added to
the level-of-detail parameter for the texture before texture sampling. The
specified value is added to the shader-supplied bias value (if any) and
subsequently clamped into the implementation-defined range [( - bias max)(bias
max)], where bias max is the value of the implementation defined constant
?GL_MAX_TEXTURE_LOD_BIAS. The initial value is 0.0.
?GL_TEXTURE_MIN_FILTER: The texture minifying function is used whenever the level-
of-detail function used when sampling from the texture determines that the texture
should be minified. There are six defined minifying functions. Two of them use
either the nearest texture elements or a weighted average of multiple texture
elements to compute the texture value. The other four use mipmaps.
A mipmap is an ordered set of arrays representing the same image at progressively
lower resolutions. If the texture has dimensions 2 n×2 m, there are max(n m)+1
mipmaps. The first mipmap is the original texture, with dimensions 2 n×2 m. Each
subsequent mipmap has dimensions 2(k-1)×2(l-1), where 2 k×2 l are the dimensions of
the previous mipmap, until either k=0 or l=0. At that point, subsequent mipmaps
have dimension 1×2(l-1) or 2(k-1)×1 until the final mipmap, which has dimension
1×1. To define the mipmaps, call gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:copyTexImage1D/7 , or gl:copyTexImage2D/8 with the level
argument indicating the order of the mipmaps. Level 0 is the original texture;
level max(n m) is the final 1×1 mipmap.
Params supplies a function for minifying the texture as one of the following:
?GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan
distance) to the specified texture coordinates.
?GL_LINEAR: Returns the weighted average of the four texture elements that are
closest to the specified texture coordinates. These can include items wrapped or
repeated from other parts of a texture, depending on the values of
?GL_TEXTURE_WRAP_S and ?GL_TEXTURE_WRAP_T , and on the exact mapping.
?GL_NEAREST_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size
of the pixel being textured and uses the ?GL_NEAREST criterion (the texture element
closest to the specified texture coordinates) to produce a texture value.
?GL_LINEAR_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size of
the pixel being textured and uses the ?GL_LINEAR criterion (a weighted average of
the four texture elements that are closest to the specified texture coordinates) to
produce a texture value.
?GL_NEAREST_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size
of the pixel being textured and uses the ?GL_NEAREST criterion (the texture element
closest to the specified texture coordinates ) to produce a texture value from each
mipmap. The final texture value is a weighted average of those two values.
?GL_LINEAR_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size
of the pixel being textured and uses the ?GL_LINEAR criterion (a weighted average
of the texture elements that are closest to the specified texture coordinates) to
produce a texture value from each mipmap. The final texture value is a weighted
average of those two values.
As more texture elements are sampled in the minification process, fewer aliasing
artifacts will be apparent. While the ?GL_NEAREST and ?GL_LINEAR minification
functions can be faster than the other four, they sample only one or multiple
texture elements to determine the texture value of the pixel being rendered and can
produce moire patterns or ragged transitions. The initial value of
?GL_TEXTURE_MIN_FILTER is ?GL_NEAREST_MIPMAP_LINEAR .
?GL_TEXTURE_MAG_FILTER: The texture magnification function is used whenever the
level-of-detail function used when sampling from the texture determines that the
texture should be magified. It sets the texture magnification function to either
?GL_NEAREST or ?GL_LINEAR (see below). ?GL_NEAREST is generally faster than
?GL_LINEAR , but it can produce textured images with sharper edges because the
transition between texture elements is not as smooth. The initial value of
?GL_TEXTURE_MAG_FILTER is ?GL_LINEAR .
?GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan
distance) to the specified texture coordinates.
?GL_LINEAR: Returns the weighted average of the texture elements that are closest
to the specified texture coordinates. These can include items wrapped or repeated
from other parts of a texture, depending on the values of ?GL_TEXTURE_WRAP_S and
?GL_TEXTURE_WRAP_T , and on the exact mapping.
?GL_TEXTURE_MIN_LOD: Sets the minimum level-of-detail parameter. This floating-
point value limits the selection of highest resolution mipmap (lowest mipmap
level). The initial value is -1000.
?GL_TEXTURE_MAX_LOD: Sets the maximum level-of-detail parameter. This floating-
point value limits the selection of the lowest resolution mipmap (highest mipmap
level). The initial value is 1000.
?GL_TEXTURE_MAX_LEVEL: Sets the index of the highest defined mipmap level. This is
an integer value. The initial value is 1000.
?GL_TEXTURE_SWIZZLE_R: Sets the swizzle that will be applied to the r component of
a texel before it is returned to the shader. Valid values for Param are ?GL_RED ,
?GL_GREEN, ?GL_BLUE, ?GL_ALPHA, ?GL_ZERO and ?GL_ONE. If ?GL_TEXTURE_SWIZZLE_R is
?GL_RED, the value for r will be taken from the first channel of the fetched texel.
If ?GL_TEXTURE_SWIZZLE_R is ?GL_GREEN , the value for r will be taken from the
second channel of the fetched texel. If ?GL_TEXTURE_SWIZZLE_R is ?GL_BLUE, the
value for r will be taken from the third channel of the fetched texel. If
?GL_TEXTURE_SWIZZLE_R is ?GL_ALPHA, the value for r will be taken from the fourth
channel of the fetched texel. If ?GL_TEXTURE_SWIZZLE_R is ?GL_ZERO , the value for
r will be subtituted with 0.0. If ?GL_TEXTURE_SWIZZLE_R is ?GL_ONE , the value for
r will be subtituted with 1.0. The initial value is ?GL_RED.
?GL_TEXTURE_SWIZZLE_G: Sets the swizzle that will be applied to the g component of
a texel before it is returned to the shader. Valid values for Param and their
effects are similar to those of ?GL_TEXTURE_SWIZZLE_R. The initial value is
?GL_GREEN .
?GL_TEXTURE_SWIZZLE_B: Sets the swizzle that will be applied to the b component of
a texel before it is returned to the shader. Valid values for Param and their
effects are similar to those of ?GL_TEXTURE_SWIZZLE_R. The initial value is
?GL_BLUE .
?GL_TEXTURE_SWIZZLE_A: Sets the swizzle that will be applied to the a component of
a texel before it is returned to the shader. Valid values for Param and their
effects are similar to those of ?GL_TEXTURE_SWIZZLE_R. The initial value is
?GL_ALPHA .
?GL_TEXTURE_SWIZZLE_RGBA: Sets the swizzles that will be applied to the r, g, b,
and a components of a texel before they are returned to the shader. Valid values
for Params and their effects are similar to those of ?GL_TEXTURE_SWIZZLE_R, except
that all channels are specified simultaneously. Setting the value of
?GL_TEXTURE_SWIZZLE_RGBA is equivalent (assuming no errors are generated) to
setting the parameters of each of ?GL_TEXTURE_SWIZZLE_R , ?GL_TEXTURE_SWIZZLE_G,
?GL_TEXTURE_SWIZZLE_B, and ?GL_TEXTURE_SWIZZLE_A successively.
?GL_TEXTURE_WRAP_S: Sets the wrap parameter for texture coordinate s to either
?GL_CLAMP_TO_EDGE , ?GL_CLAMP_TO_BORDER, ?GL_MIRRORED_REPEAT, or ?GL_REPEAT.
?GL_CLAMP_TO_EDGE causes s coordinates to be clamped to the range [(1 2/N) 1-(1
2/N)], where N is the size of the texture in the direction of clamping.
?GL_CLAMP_TO_BORDER evaluates s coordinates in a similar manner to
?GL_CLAMP_TO_EDGE. However, in cases where clamping would have occurred in
?GL_CLAMP_TO_EDGE mode, the fetched texel data is substituted with the values
specified by ?GL_TEXTURE_BORDER_COLOR. ?GL_REPEAT causes the integer part of the s
coordinate to be ignored; the GL uses only the fractional part, thereby creating a
repeating pattern. ?GL_MIRRORED_REPEAT causes the s coordinate to be set to the
fractional part of the texture coordinate if the integer part of s is even; if the
integer part of s is odd, then the s texture coordinate is set to 1- frac(s), where
frac(s) represents the fractional part of s. Initially, ?GL_TEXTURE_WRAP_S is set
to ?GL_REPEAT.
?GL_TEXTURE_WRAP_T: Sets the wrap parameter for texture coordinate t to either
?GL_CLAMP_TO_EDGE , ?GL_CLAMP_TO_BORDER, ?GL_MIRRORED_REPEAT, or ?GL_REPEAT. See
the discussion under ?GL_TEXTURE_WRAP_S. Initially, ?GL_TEXTURE_WRAP_T is set to
?GL_REPEAT.
?GL_TEXTURE_WRAP_R: Sets the wrap parameter for texture coordinate r to either
?GL_CLAMP_TO_EDGE , ?GL_CLAMP_TO_BORDER, ?GL_MIRRORED_REPEAT, or ?GL_REPEAT. See
the discussion under ?GL_TEXTURE_WRAP_S. Initially, ?GL_TEXTURE_WRAP_R is set to
?GL_REPEAT.
See external documentation.
texParameteri(Target, Pname, Param) -> ok
Types:
Target = enum()
Pname = enum()
Param = integer()
See texParameterf/3
texParameterfv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {float()}
See texParameterf/3
texParameteriv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer()}
See texParameterf/3
getTexParameterfv(Target, Pname) -> {float(), float(), float(), float()}
Types:
Target = enum()
Pname = enum()
Return texture parameter values
gl:getTexParameter returns in Params the value or values of the texture parameter
specified as Pname . Target defines the target texture. ?GL_TEXTURE_1D,
?GL_TEXTURE_2D, ?GL_TEXTURE_3D, ?GL_TEXTURE_1D_ARRAY, ?GL_TEXTURE_2D_ARRAY ,
?GL_TEXTURE_RECTANGLE, ?GL_TEXTURE_CUBE_MAP, ?GL_TEXTURE_CUBE_MAP_ARRAY specify
one-, two-, or three-dimensional, one-dimensional array, two-dimensional array,
rectangle, cube-mapped or cube-mapped array texturing, respectively. Pname accepts
the same symbols as gl:texParameterf/3 , with the same interpretations:
?GL_TEXTURE_MAG_FILTER: Returns the single-valued texture magnification filter, a
symbolic constant. The initial value is ?GL_LINEAR.
?GL_TEXTURE_MIN_FILTER: Returns the single-valued texture minification filter, a
symbolic constant. The initial value is ?GL_NEAREST_MIPMAP_LINEAR.
?GL_TEXTURE_MIN_LOD: Returns the single-valued texture minimum level-of-detail
value. The initial value is -1000.
?GL_TEXTURE_MAX_LOD: Returns the single-valued texture maximum level-of-detail
value. The initial value is 1000.
?GL_TEXTURE_BASE_LEVEL: Returns the single-valued base texture mipmap level. The
initial value is 0.
?GL_TEXTURE_MAX_LEVEL: Returns the single-valued maximum texture mipmap array
level. The initial value is 1000.
?GL_TEXTURE_SWIZZLE_R: Returns the red component swizzle. The initial value is
?GL_RED .
?GL_TEXTURE_SWIZZLE_G: Returns the green component swizzle. The initial value is
?GL_GREEN .
?GL_TEXTURE_SWIZZLE_B: Returns the blue component swizzle. The initial value is
?GL_BLUE .
?GL_TEXTURE_SWIZZLE_A: Returns the alpha component swizzle. The initial value is
?GL_ALPHA .
?GL_TEXTURE_SWIZZLE_RGBA: Returns the component swizzle for all channels in a
single query.
?GL_TEXTURE_WRAP_S: Returns the single-valued wrapping function for texture
coordinate s, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_WRAP_T: Returns the single-valued wrapping function for texture
coordinate t, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_WRAP_R: Returns the single-valued wrapping function for texture
coordinate r, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_BORDER_COLOR: Returns four integer or floating-point numbers that
comprise the RGBA color of the texture border. Floating-point values are returned
in the range [0 1]. Integer values are returned as a linear mapping of the internal
floating-point representation such that 1.0 maps to the most positive representable
integer and -1.0 maps to the most negative representable integer. The initial value
is (0, 0, 0, 0).
?GL_TEXTURE_COMPARE_MODE: Returns a single-valued texture comparison mode, a
symbolic constant. The initial value is ?GL_NONE. See gl:texParameterf/3 .
?GL_TEXTURE_COMPARE_FUNC: Returns a single-valued texture comparison function, a
symbolic constant. The initial value is ?GL_LEQUAL. See gl:texParameterf/3 .
In addition to the parameters that may be set with gl:texParameterf/3 ,
gl:getTexParameter accepts the following read-only parameters:
?GL_TEXTURE_IMMUTABLE_FORMAT: Returns non-zero if the texture has an immutable
format. Textures become immutable if their storage is specified with
gl:texStorage1D/4 , gl:texStorage2D/5 or gl:texStorage3D/6 . The initial value is
?GL_FALSE .
See external documentation.
getTexParameteriv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
See getTexParameterfv/2
getTexLevelParameterfv(Target, Level, Pname) -> {float()}
Types:
Target = enum()
Level = integer()
Pname = enum()
Return texture parameter values for a specific level of detail
gl:getTexLevelParameter returns in Params texture parameter values for a specific
level-of-detail value, specified as Level . Target defines the target texture,
either ?GL_TEXTURE_1D, ?GL_TEXTURE_2D, ?GL_TEXTURE_3D, ?GL_PROXY_TEXTURE_1D ,
?GL_PROXY_TEXTURE_2D, ?GL_PROXY_TEXTURE_3D, ?GL_TEXTURE_CUBE_MAP_POSITIVE_X ,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_X, ?GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Y , ?GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or ?GL_PROXY_TEXTURE_CUBE_MAP .
?GL_MAX_TEXTURE_SIZE, and ?GL_MAX_3D_TEXTURE_SIZE are not really descriptive
enough. It has to report the largest square texture image that can be accommodated
with mipmaps and borders, but a long skinny texture, or a texture without mipmaps
and borders, may easily fit in texture memory. The proxy targets allow the user to
more accurately query whether the GL can accommodate a texture of a given
configuration. If the texture cannot be accommodated, the texture state variables,
which may be queried with gl:getTexLevelParameter , are set to 0. If the texture
can be accommodated, the texture state values will be set as they would be set for
a non-proxy target.
Pname specifies the texture parameter whose value or values will be returned.
The accepted parameter names are as follows:
?GL_TEXTURE_WIDTH: Params returns a single value, the width of the texture image.
This value includes the border of the texture image. The initial value is 0.
?GL_TEXTURE_HEIGHT: Params returns a single value, the height of the texture image.
This value includes the border of the texture image. The initial value is 0.
?GL_TEXTURE_DEPTH: Params returns a single value, the depth of the texture image.
This value includes the border of the texture image. The initial value is 0.
?GL_TEXTURE_INTERNAL_FORMAT: Params returns a single value, the internal format of
the texture image.
?GL_TEXTURE_RED_TYPE,
?GL_TEXTURE_GREEN_TYPE,
?GL_TEXTURE_BLUE_TYPE,
?GL_TEXTURE_ALPHA_TYPE,
?GL_TEXTURE_DEPTH_TYPE: The data type used to store the component. The types
?GL_NONE , ?GL_SIGNED_NORMALIZED, ?GL_UNSIGNED_NORMALIZED, ?GL_FLOAT, ?GL_INT , and
?GL_UNSIGNED_INT may be returned to indicate signed normalized fixed-point,
unsigned normalized fixed-point, floating-point, integer unnormalized, and unsigned
integer unnormalized components, respectively.
?GL_TEXTURE_RED_SIZE,
?GL_TEXTURE_GREEN_SIZE,
?GL_TEXTURE_BLUE_SIZE,
?GL_TEXTURE_ALPHA_SIZE,
?GL_TEXTURE_DEPTH_SIZE: The internal storage resolution of an individual component.
The resolution chosen by the GL will be a close match for the resolution requested
by the user with the component argument of gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:copyTexImage1D/7 , and gl:copyTexImage2D/8 . The initial
value is 0.
?GL_TEXTURE_COMPRESSED: Params returns a single boolean value indicating if the
texture image is stored in a compressed internal format. The initiali value is
?GL_FALSE .
?GL_TEXTURE_COMPRESSED_IMAGE_SIZE: Params returns a single integer value, the
number of unsigned bytes of the compressed texture image that would be returned
from gl:getCompressedTexImage/3 .
See external documentation.
getTexLevelParameteriv(Target, Level, Pname) -> {integer()}
Types:
Target = enum()
Level = integer()
Pname = enum()
See getTexLevelParameterfv/3
texImage1D(Target, Level, InternalFormat, Width, Border, Format, Type, Pixels) -> ok
Types:
Target = enum()
Level = integer()
InternalFormat = integer()
Width = integer()
Border = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
Specify a one-dimensional texture image
Texturing maps a portion of a specified texture image onto each graphical primitive
for which texturing is enabled. To enable and disable one-dimensional texturing,
call gl:enable/1 and gl:enable/1 with argument ?GL_TEXTURE_1D.
Texture images are defined with gl:texImage1D. The arguments describe the
parameters of the texture image, such as width, width of the border, level-of-
detail number (see gl:texParameterf/3 ), and the internal resolution and format
used to store the image. The last three arguments describe how the image is
represented in memory.
If Target is ?GL_PROXY_TEXTURE_1D, no data is read from Data , but all of the
texture image state is recalculated, checked for consistency, and checked against
the implementation's capabilities. If the implementation cannot handle a texture of
the requested texture size, it sets all of the image state to 0, but does not
generate an error (see gl:getError/0 ). To query for an entire mipmap array, use an
image array level greater than or equal to 1.
If Target is ?GL_TEXTURE_1D, data is read from Data as a sequence of signed or
unsigned bytes, shorts, or longs, or single-precision floating-point values,
depending on Type . These values are grouped into sets of one, two, three, or four
values, depending on Format , to form elements. Each data byte is treated as eight
1-bit elements, with bit ordering determined by ?GL_UNPACK_LSB_FIRST (see
gl:pixelStoref/2 ).
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
The first element corresponds to the left end of the texture array. Subsequent
elements progress left-to-right through the remaining texels in the texture array.
The final element corresponds to the right end of the texture array.
Format determines the composition of each element in Data . It can assume one of
these symbolic values:
?GL_RED: Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and blue, and
1 for alpha. Each component is then multiplied by the signed scale factor
?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RG: Each element is a single red/green double The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for blue, and 1 for
alpha. Each component is then multiplied by the signed scale factor ?GL_c_SCALE,
added to the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGB
?GL_BGR: Each element is an RGB triple. The GL converts it to floating point and
assembles it into an RGBA element by attaching 1 for alpha. Each component is then
multiplied by the signed scale factor ?GL_c_SCALE, added to the signed bias
?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGBA
?GL_BGRA: Each element contains all four components. Each component is multiplied
by the signed scale factor ?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and
clamped to the range [0,1].
?GL_DEPTH_COMPONENT: Each element is a single depth value. The GL converts it to
floating point, multiplies by the signed scale factor ?GL_DEPTH_SCALE, adds the
signed bias ?GL_DEPTH_BIAS, and clamps to the range [0,1].
If an application wants to store the texture at a certain resolution or in a
certain format, it can request the resolution and format with InternalFormat . The
GL will choose an internal representation that closely approximates that requested
by InternalFormat , but it may not match exactly. (The representations specified by
?GL_RED, ?GL_RG , ?GL_RGB and ?GL_RGBA must match exactly.)
InternalFormat may be one of the base internal formats shown in Table 1, below
InternalFormat may also be one of the sized internal formats shown in Table 2,
below
Finally, InternalFormat may also be one of the generic or compressed compressed
texture formats shown in Table 3 below
If the InternalFormat parameter is one of the generic compressed formats,
?GL_COMPRESSED_RED , ?GL_COMPRESSED_RG, ?GL_COMPRESSED_RGB, or ?GL_COMPRESSED_RGBA,
the GL will replace the internal format with the symbolic constant for a specific
internal format and compress the texture before storage. If no corresponding
internal format is available, or the GL can not compress that image for any reason,
the internal format is instead replaced with a corresponding base internal format.
If the InternalFormat parameter is ?GL_SRGB, ?GL_SRGB8, ?GL_SRGB_ALPHA or
?GL_SRGB8_ALPHA8, the texture is treated as if the red, green, or blue components
are encoded in the sRGB color space. Any alpha component is left unchanged. The
conversion from the sRGB encoded component c s to a linear component c l is:
c l={ c s/12.92if c s≤ 0.04045( c s+0.055/1.055) 2.4if c s> 0.04045
Assume c s is the sRGB component in the range [0,1].
Use the ?GL_PROXY_TEXTURE_1D target to try out a resolution and format. The
implementation will update and recompute its best match for the requested storage
resolution and format. To then query this state, call gl:getTexLevelParameterfv/3 .
If the texture cannot be accommodated, texture state is set to 0.
A one-component texture image uses only the red component of the RGBA color from
Data . A two-component image uses the R and A values. A three-component image uses
the R, G, and B values. A four-component image uses all of the RGBA components.
Image-based shadowing can be enabled by comparing texture r coordinates to depth
texture values to generate a boolean result. See gl:texParameterf/3 for details on
texture comparison.
See external documentation.
texImage2D(Target, Level, InternalFormat, Width, Height, Border, Format, Type, Pixels) ->
ok
Types:
Target = enum()
Level = integer()
InternalFormat = integer()
Width = integer()
Height = integer()
Border = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
Specify a two-dimensional texture image
Texturing allows elements of an image array to be read by shaders.
To define texture images, call gl:texImage2D. The arguments describe the parameters
of the texture image, such as height, width, width of the border, level-of-detail
number (see gl:texParameterf/3 ), and number of color components provided. The last
three arguments describe how the image is represented in memory.
If Target is ?GL_PROXY_TEXTURE_2D, ?GL_PROXY_TEXTURE_1D_ARRAY,
?GL_PROXY_TEXTURE_CUBE_MAP , or ?GL_PROXY_TEXTURE_RECTANGLE, no data is read from
Data , but all of the texture image state is recalculated, checked for consistency,
and checked against the implementation's capabilities. If the implementation cannot
handle a texture of the requested texture size, it sets all of the image state to
0, but does not generate an error (see gl:getError/0 ). To query for an entire
mipmap array, use an image array level greater than or equal to 1.
If Target is ?GL_TEXTURE_2D, ?GL_TEXTURE_RECTANGLE or one of the
?GL_TEXTURE_CUBE_MAP targets, data is read from Data as a sequence of signed or
unsigned bytes, shorts, or longs, or single-precision floating-point values,
depending on Type . These values are grouped into sets of one, two, three, or four
values, depending on Format , to form elements. Each data byte is treated as eight
1-bit elements, with bit ordering determined by ?GL_UNPACK_LSB_FIRST (see
gl:pixelStoref/2 ).
If Target is ?GL_TEXTURE_1D_ARRAY, data is interpreted as an array of one-
dimensional images.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
The first element corresponds to the lower left corner of the texture image.
Subsequent elements progress left-to-right through the remaining texels in the
lowest row of the texture image, and then in successively higher rows of the
texture image. The final element corresponds to the upper right corner of the
texture image.
Format determines the composition of each element in Data . It can assume one of
these symbolic values:
?GL_RED: Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and blue, and
1 for alpha. Each component is then multiplied by the signed scale factor
?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RG: Each element is a red/green double. The GL converts it to floating point
and assembles it into an RGBA element by attaching 0 for blue, and 1 for alpha.
Each component is then multiplied by the signed scale factor ?GL_c_SCALE, added to
the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGB
?GL_BGR: Each element is an RGB triple. The GL converts it to floating point and
assembles it into an RGBA element by attaching 1 for alpha. Each component is then
multiplied by the signed scale factor ?GL_c_SCALE, added to the signed bias
?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGBA
?GL_BGRA: Each element contains all four components. Each component is multiplied
by the signed scale factor ?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and
clamped to the range [0,1].
?GL_DEPTH_COMPONENT: Each element is a single depth value. The GL converts it to
floating point, multiplies by the signed scale factor ?GL_DEPTH_SCALE, adds the
signed bias ?GL_DEPTH_BIAS, and clamps to the range [0,1].
?GL_DEPTH_STENCIL: Each element is a pair of depth and stencil values. The depth
component of the pair is interpreted as in ?GL_DEPTH_COMPONENT. The stencil
component is interpreted based on specified the depth + stencil internal format.
If an application wants to store the texture at a certain resolution or in a
certain format, it can request the resolution and format with InternalFormat . The
GL will choose an internal representation that closely approximates that requested
by InternalFormat , but it may not match exactly. (The representations specified by
?GL_RED, ?GL_RG , ?GL_RGB, and ?GL_RGBA must match exactly.)
InternalFormat may be one of the base internal formats shown in Table 1, below
InternalFormat may also be one of the sized internal formats shown in Table 2,
below
Finally, InternalFormat may also be one of the generic or compressed compressed
texture formats shown in Table 3 below
If the InternalFormat parameter is one of the generic compressed formats,
?GL_COMPRESSED_RED , ?GL_COMPRESSED_RG, ?GL_COMPRESSED_RGB, or ?GL_COMPRESSED_RGBA,
the GL will replace the internal format with the symbolic constant for a specific
internal format and compress the texture before storage. If no corresponding
internal format is available, or the GL can not compress that image for any reason,
the internal format is instead replaced with a corresponding base internal format.
If the InternalFormat parameter is ?GL_SRGB, ?GL_SRGB8, ?GL_SRGB_ALPHA , or
?GL_SRGB8_ALPHA8, the texture is treated as if the red, green, or blue components
are encoded in the sRGB color space. Any alpha component is left unchanged. The
conversion from the sRGB encoded component c s to a linear component c l is:
c l={ c s/12.92if c s≤ 0.04045( c s+0.055/1.055) 2.4if c s> 0.04045
Assume c s is the sRGB component in the range [0,1].
Use the ?GL_PROXY_TEXTURE_2D, ?GL_PROXY_TEXTURE_1D_ARRAY,
?GL_PROXY_TEXTURE_RECTANGLE , or ?GL_PROXY_TEXTURE_CUBE_MAP target to try out a
resolution and format. The implementation will update and recompute its best match
for the requested storage resolution and format. To then query this state, call
gl:getTexLevelParameterfv/3 . If the texture cannot be accommodated, texture state
is set to 0.
A one-component texture image uses only the red component of the RGBA color
extracted from Data . A two-component image uses the R and G values. A three-
component image uses the R, G, and B values. A four-component image uses all of the
RGBA components.
Image-based shadowing can be enabled by comparing texture r coordinates to depth
texture values to generate a boolean result. See gl:texParameterf/3 for details on
texture comparison.
See external documentation.
getTexImage(Target, Level, Format, Type, Pixels) -> ok
Types:
Target = enum()
Level = integer()
Format = enum()
Type = enum()
Pixels = mem()
Return a texture image
gl:getTexImage returns a texture image into Img . Target specifies whether the
desired texture image is one specified by gl:texImage1D/8 (?GL_TEXTURE_1D ),
gl:texImage2D/9 (?GL_TEXTURE_1D_ARRAY, ?GL_TEXTURE_RECTANGLE, ?GL_TEXTURE_2D or any
of ?GL_TEXTURE_CUBE_MAP_*), or gl:texImage3D/10 (?GL_TEXTURE_2D_ARRAY ,
?GL_TEXTURE_3D). Level specifies the level-of-detail number of the desired image.
Format and Type specify the format and type of the desired image array. See the
reference page for gl:texImage1D/8 for a description of the acceptable values for
the Format and Type parameters, respectively.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a texture image is requested, Img is treated as a byte
offset into the buffer object's data store.
To understand the operation of gl:getTexImage, consider the selected internal four-
component texture image to be an RGBA color buffer the size of the image. The
semantics of gl:getTexImage are then identical to those of gl:readPixels/7 , with
the exception that no pixel transfer operations are performed, when called with the
same Format and Type , with x and y set to 0, width set to the width of the texture
image and height set to 1 for 1D images, or to the height of the texture image for
2D images.
If the selected texture image does not contain four components, the following
mappings are applied. Single-component textures are treated as RGBA buffers with
red set to the single-component value, green set to 0, blue set to 0, and alpha set
to 1. Two-component textures are treated as RGBA buffers with red set to the value
of component zero, alpha set to the value of component one, and green and blue set
to 0. Finally, three-component textures are treated as RGBA buffers with red set to
component zero, green set to component one, blue set to component two, and alpha
set to 1.
To determine the required size of Img , use gl:getTexLevelParameterfv/3 to
determine the dimensions of the internal texture image, then scale the required
number of pixels by the storage required for each pixel, based on Format and Type .
Be sure to take the pixel storage parameters into account, especially
?GL_PACK_ALIGNMENT .
See external documentation.
genTextures(N) -> [integer()]
Types:
N = integer()
Generate texture names
gl:genTextures returns N texture names in Textures . There is no guarantee that the
names form a contiguous set of integers; however, it is guaranteed that none of the
returned names was in use immediately before the call to gl:genTextures.
The generated textures have no dimensionality; they assume the dimensionality of
the texture target to which they are first bound (see gl:bindTexture/2 ).
Texture names returned by a call to gl:genTextures are not returned by subsequent
calls, unless they are first deleted with gl:deleteTextures/1 .
See external documentation.
deleteTextures(Textures) -> ok
Types:
Textures = [integer()]
Delete named textures
gl:deleteTextures deletes N textures named by the elements of the array Textures .
After a texture is deleted, it has no contents or dimensionality, and its name is
free for reuse (for example by gl:genTextures/1 ). If a texture that is currently
bound is deleted, the binding reverts to 0 (the default texture).
gl:deleteTextures silently ignores 0's and names that do not correspond to existing
textures.
See external documentation.
bindTexture(Target, Texture) -> ok
Types:
Target = enum()
Texture = integer()
Bind a named texture to a texturing target
gl:bindTexture lets you create or use a named texture. Calling gl:bindTexture with
Target set to ?GL_TEXTURE_1D, ?GL_TEXTURE_2D, ?GL_TEXTURE_3D , or
?GL_TEXTURE_1D_ARRAY, ?GL_TEXTURE_2D_ARRAY, ?GL_TEXTURE_RECTANGLE ,
?GL_TEXTURE_CUBE_MAP, ?GL_TEXTURE_2D_MULTISAMPLE or
?GL_TEXTURE_2D_MULTISAMPLE_ARRAY and Texture set to the name of the new texture
binds the texture name to the target. When a texture is bound to a target, the
previous binding for that target is automatically broken.
Texture names are unsigned integers. The value zero is reserved to represent the
default texture for each texture target. Texture names and the corresponding
texture contents are local to the shared object space of the current GL rendering
context; two rendering contexts share texture names only if they explicitly enable
sharing between contexts through the appropriate GL windows interfaces functions.
You must use gl:genTextures/1 to generate a set of new texture names.
When a texture is first bound, it assumes the specified target: A texture first
bound to ?GL_TEXTURE_1D becomes one-dimensional texture, a texture first bound to
?GL_TEXTURE_2D becomes two-dimensional texture, a texture first bound to
?GL_TEXTURE_3D becomes three-dimensional texture, a texture first bound to
?GL_TEXTURE_1D_ARRAY becomes one-dimensional array texture, a texture first bound
to ?GL_TEXTURE_2D_ARRAY becomes two-dimensional arary texture, a texture first
bound to ?GL_TEXTURE_RECTANGLE becomes rectangle texture, a, texture first bound to
?GL_TEXTURE_CUBE_MAP becomes a cube-mapped texture, a texture first bound to
?GL_TEXTURE_2D_MULTISAMPLE becomes a two-dimensional multisampled texture, and a
texture first bound to ?GL_TEXTURE_2D_MULTISAMPLE_ARRAY becomes a two-dimensional
multisampled array texture. The state of a one-dimensional texture immediately
after it is first bound is equivalent to the state of the default ?GL_TEXTURE_1D at
GL initialization, and similarly for the other texture types.
While a texture is bound, GL operations on the target to which it is bound affect
the bound texture, and queries of the target to which it is bound return state from
the bound texture. In effect, the texture targets become aliases for the textures
currently bound to them, and the texture name zero refers to the default textures
that were bound to them at initialization.
A texture binding created with gl:bindTexture remains active until a different
texture is bound to the same target, or until the bound texture is deleted with
gl:deleteTextures/1 .
Once created, a named texture may be re-bound to its same original target as often
as needed. It is usually much faster to use gl:bindTexture to bind an existing
named texture to one of the texture targets than it is to reload the texture image
using gl:texImage1D/8 , gl:texImage2D/9 , gl:texImage3D/10 or another similar
function.
See external documentation.
prioritizeTextures(Textures, Priorities) -> ok
Types:
Textures = [integer()]
Priorities = [clamp()]
Set texture residence priority
gl:prioritizeTextures assigns the N texture priorities given in Priorities to the N
textures named in Textures .
The GL establishes a working set of textures that are resident in texture memory.
These textures may be bound to a texture target much more efficiently than textures
that are not resident. By specifying a priority for each texture,
gl:prioritizeTextures allows applications to guide the GL implementation in
determining which textures should be resident.
The priorities given in Priorities are clamped to the range [0 1] before they are
assigned. 0 indicates the lowest priority; textures with priority 0 are least
likely to be resident. 1 indicates the highest priority; textures with priority 1
are most likely to be resident. However, textures are not guaranteed to be resident
until they are used.
gl:prioritizeTextures silently ignores attempts to prioritize texture 0 or any
texture name that does not correspond to an existing texture.
gl:prioritizeTextures does not require that any of the textures named by Textures
be bound to a texture target. gl:texParameterf/3 may also be used to set a
texture's priority, but only if the texture is currently bound. This is the only
way to set the priority of a default texture.
See external documentation.
areTexturesResident(Textures) -> {0 | 1, Residences::[0 | 1]}
Types:
Textures = [integer()]
Determine if textures are loaded in texture memory
GL establishes a working set of textures that are resident in texture memory. These
textures can be bound to a texture target much more efficiently than textures that
are not resident.
gl:areTexturesResident queries the texture residence status of the N textures named
by the elements of Textures . If all the named textures are resident,
gl:areTexturesResident returns ?GL_TRUE, and the contents of Residences are
undisturbed. If not all the named textures are resident, gl:areTexturesResident
returns ?GL_FALSE, and detailed status is returned in the N elements of Residences
. If an element of Residences is ?GL_TRUE, then the texture named by the
corresponding element of Textures is resident.
The residence status of a single bound texture may also be queried by calling
gl:getTexParameterfv/2 with the target argument set to the target to which the
texture is bound, and the pname argument set to ?GL_TEXTURE_RESIDENT. This is the
only way that the residence status of a default texture can be queried.
See external documentation.
isTexture(Texture) -> 0 | 1
Types:
Texture = integer()
Determine if a name corresponds to a texture
gl:isTexture returns ?GL_TRUE if Texture is currently the name of a texture. If
Texture is zero, or is a non-zero value that is not currently the name of a
texture, or if an error occurs, gl:isTexture returns ?GL_FALSE.
A name returned by gl:genTextures/1 , but not yet associated with a texture by
calling gl:bindTexture/2 , is not the name of a texture.
See external documentation.
texSubImage1D(Target, Level, Xoffset, Width, Format, Type, Pixels) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Width = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
glTexSubImage
See external documentation.
texSubImage2D(Target, Level, Xoffset, Yoffset, Width, Height, Format, Type, Pixels) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
Width = integer()
Height = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
glTexSubImage
See external documentation.
copyTexImage1D(Target, Level, Internalformat, X, Y, Width, Border) -> ok
Types:
Target = enum()
Level = integer()
Internalformat = enum()
X = integer()
Y = integer()
Width = integer()
Border = integer()
Copy pixels into a 1D texture image
gl:copyTexImage1D defines a one-dimensional texture image with pixels from the
current ?GL_READ_BUFFER.
The screen-aligned pixel row with left corner at (x y) and with a length of
width+2(border) defines the texture array at the mipmap level specified by Level .
Internalformat specifies the internal format of the texture array.
The pixels in the row are processed exactly as if gl:readPixels/7 had been called,
but the process stops just before final conversion. At this point all pixel
component values are clamped to the range [0 1] and then converted to the texture's
internal format for storage in the texel array.
Pixel ordering is such that lower x screen coordinates correspond to lower texture
coordinates.
If any of the pixels within the specified row of the current ?GL_READ_BUFFER are
outside the window associated with the current rendering context, then the values
obtained for those pixels are undefined.
gl:copyTexImage1D defines a one-dimensional texture image with pixels from the
current ?GL_READ_BUFFER.
When Internalformat is one of the sRGB types, the GL does not automatically convert
the source pixels to the sRGB color space. In this case, the gl:pixelMap function
can be used to accomplish the conversion.
See external documentation.
copyTexImage2D(Target, Level, Internalformat, X, Y, Width, Height, Border) -> ok
Types:
Target = enum()
Level = integer()
Internalformat = enum()
X = integer()
Y = integer()
Width = integer()
Height = integer()
Border = integer()
Copy pixels into a 2D texture image
gl:copyTexImage2D defines a two-dimensional texture image, or cube-map texture
image with pixels from the current ?GL_READ_BUFFER.
The screen-aligned pixel rectangle with lower left corner at ( X , Y ) and with a
width of width+2(border) and a height of height+2(border) defines the texture array
at the mipmap level specified by Level . Internalformat specifies the internal
format of the texture array.
The pixels in the rectangle are processed exactly as if gl:readPixels/7 had been
called, but the process stops just before final conversion. At this point all pixel
component values are clamped to the range [0 1] and then converted to the texture's
internal format for storage in the texel array.
Pixel ordering is such that lower x and y screen coordinates correspond to lower s
and t texture coordinates.
If any of the pixels within the specified rectangle of the current ?GL_READ_BUFFER
are outside the window associated with the current rendering context, then the
values obtained for those pixels are undefined.
When Internalformat is one of the sRGB types, the GL does not automatically convert
the source pixels to the sRGB color space. In this case, the gl:pixelMap function
can be used to accomplish the conversion.
See external documentation.
copyTexSubImage1D(Target, Level, Xoffset, X, Y, Width) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
X = integer()
Y = integer()
Width = integer()
Copy a one-dimensional texture subimage
gl:copyTexSubImage1D replaces a portion of a one-dimensional texture image with
pixels from the current ?GL_READ_BUFFER (rather than from main memory, as is the
case for gl:texSubImage1D/7 ).
The screen-aligned pixel row with left corner at ( X , Y ), and with length Width
replaces the portion of the texture array with x indices Xoffset through xoffset
+width-1, inclusive. The destination in the texture array may not include any
texels outside the texture array as it was originally specified.
The pixels in the row are processed exactly as if gl:readPixels/7 had been called,
but the process stops just before final conversion. At this point, all pixel
component values are clamped to the range [0 1] and then converted to the texture's
internal format for storage in the texel array.
It is not an error to specify a subtexture with zero width, but such a
specification has no effect. If any of the pixels within the specified row of the
current ?GL_READ_BUFFER are outside the read window associated with the current
rendering context, then the values obtained for those pixels are undefined.
No change is made to the internalformat, width, or border parameters of the
specified texture array or to texel values outside the specified subregion.
See external documentation.
copyTexSubImage2D(Target, Level, Xoffset, Yoffset, X, Y, Width, Height) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
X = integer()
Y = integer()
Width = integer()
Height = integer()
Copy a two-dimensional texture subimage
gl:copyTexSubImage2D replaces a rectangular portion of a two-dimensional texture
image or cube-map texture image with pixels from the current ?GL_READ_BUFFER
(rather than from main memory, as is the case for gl:texSubImage1D/7 ).
The screen-aligned pixel rectangle with lower left corner at (x y) and with width
Width and height Height replaces the portion of the texture array with x indices
Xoffset through xoffset+width-1, inclusive, and y indices Yoffset through
yoffset+height -1, inclusive, at the mipmap level specified by Level .
The pixels in the rectangle are processed exactly as if gl:readPixels/7 had been
called, but the process stops just before final conversion. At this point, all
pixel component values are clamped to the range [0 1] and then converted to the
texture's internal format for storage in the texel array.
The destination rectangle in the texture array may not include any texels outside
the texture array as it was originally specified. It is not an error to specify a
subtexture with zero width or height, but such a specification has no effect.
If any of the pixels within the specified rectangle of the current ?GL_READ_BUFFER
are outside the read window associated with the current rendering context, then the
values obtained for those pixels are undefined.
No change is made to the internalformat, width, height, or border parameters of the
specified texture array or to texel values outside the specified subregion.
See external documentation.
map1d(Target, U1, U2, Stride, Order, Points) -> ok
Types:
Target = enum()
U1 = float()
U2 = float()
Stride = integer()
Order = integer()
Points = binary()
glMap
See external documentation.
map1f(Target, U1, U2, Stride, Order, Points) -> ok
Types:
Target = enum()
U1 = float()
U2 = float()
Stride = integer()
Order = integer()
Points = binary()
glMap
See external documentation.
map2d(Target, U1, U2, Ustride, Uorder, V1, V2, Vstride, Vorder, Points) -> ok
Types:
Target = enum()
U1 = float()
U2 = float()
Ustride = integer()
Uorder = integer()
V1 = float()
V2 = float()
Vstride = integer()
Vorder = integer()
Points = binary()
glMap
See external documentation.
map2f(Target, U1, U2, Ustride, Uorder, V1, V2, Vstride, Vorder, Points) -> ok
Types:
Target = enum()
U1 = float()
U2 = float()
Ustride = integer()
Uorder = integer()
V1 = float()
V2 = float()
Vstride = integer()
Vorder = integer()
Points = binary()
glMap
See external documentation.
getMapdv(Target, Query, V) -> ok
Types:
Target = enum()
Query = enum()
V = mem()
Return evaluator parameters
gl:map1d/6 and gl:map1d/6 define evaluators. gl:getMap returns evaluator
parameters. Target chooses a map, Query selects a specific parameter, and V points
to storage where the values will be returned.
The acceptable values for the Target parameter are described in the gl:map1d/6 and
gl:map1d/6 reference pages.
Query can assume the following values:
?GL_COEFF: V returns the control points for the evaluator function. One-dimensional
evaluators return order control points, and two-dimensional evaluators return
uorder×vorder control points. Each control point consists of one, two, three, or
four integer, single-precision floating-point, or double-precision floating-point
values, depending on the type of the evaluator. The GL returns two-dimensional
control points in row-major order, incrementing the uorder index quickly and the
vorder index after each row. Integer values, when requested, are computed by
rounding the internal floating-point values to the nearest integer values.
?GL_ORDER: V returns the order of the evaluator function. One-dimensional
evaluators return a single value, order. The initial value is 1. Two-dimensional
evaluators return two values, uorder and vorder. The initial value is 1,1.
?GL_DOMAIN: V returns the linear u and v mapping parameters. One-dimensional
evaluators return two values, u1 and u2, as specified by gl:map1d/6 . Two-
dimensional evaluators return four values ( u1, u2, v1, and v2) as specified by
gl:map1d/6 . Integer values, when requested, are computed by rounding the internal
floating-point values to the nearest integer values.
See external documentation.
getMapfv(Target, Query, V) -> ok
Types:
Target = enum()
Query = enum()
V = mem()
See getMapdv/3
getMapiv(Target, Query, V) -> ok
Types:
Target = enum()
Query = enum()
V = mem()
See getMapdv/3
evalCoord1d(U) -> ok
Types:
U = float()
Evaluate enabled one- and two-dimensional maps
gl:evalCoord1 evaluates enabled one-dimensional maps at argument U . gl:evalCoord2
does the same for two-dimensional maps using two domain values, U and V . To define
a map, call gl:map1d/6 and gl:map1d/6 ; to enable and disable it, call gl:enable/1
and gl:enable/1 .
When one of the gl:evalCoord commands is issued, all currently enabled maps of the
indicated dimension are evaluated. Then, for each enabled map, it is as if the
corresponding GL command had been issued with the computed value. That is, if
?GL_MAP1_INDEX or ?GL_MAP2_INDEX is enabled, a gl:indexd/1 command is simulated. If
?GL_MAP1_COLOR_4 or ?GL_MAP2_COLOR_4 is enabled, a gl:color3b/3 command is
simulated. If ?GL_MAP1_NORMAL or ?GL_MAP2_NORMAL is enabled, a normal vector is
produced, and if any of ?GL_MAP1_TEXTURE_COORD_1, ?GL_MAP1_TEXTURE_COORD_2 ,
?GL_MAP1_TEXTURE_COORD_3, ?GL_MAP1_TEXTURE_COORD_4, ?GL_MAP2_TEXTURE_COORD_1 ,
?GL_MAP2_TEXTURE_COORD_2, ?GL_MAP2_TEXTURE_COORD_3, or ?GL_MAP2_TEXTURE_COORD_4 is
enabled, then an appropriate gl:texCoord1d/1 command is simulated.
For color, color index, normal, and texture coordinates the GL uses evaluated
values instead of current values for those evaluations that are enabled, and
current values otherwise, However, the evaluated values do not update the current
values. Thus, if gl:vertex2d/2 commands are interspersed with gl:evalCoord
commands, the color, normal, and texture coordinates associated with the
gl:vertex2d/2 commands are not affected by the values generated by the gl:evalCoord
commands, but only by the most recent gl:color3b/3 , gl:indexd/1 , gl:normal3b/3 ,
and gl:texCoord1d/1 commands.
No commands are issued for maps that are not enabled. If more than one texture
evaluation is enabled for a particular dimension (for example,
?GL_MAP2_TEXTURE_COORD_1 and ?GL_MAP2_TEXTURE_COORD_2 ), then only the evaluation
of the map that produces the larger number of coordinates (in this case,
?GL_MAP2_TEXTURE_COORD_2) is carried out. ?GL_MAP1_VERTEX_4 overrides
?GL_MAP1_VERTEX_3, and ?GL_MAP2_VERTEX_4 overrides ?GL_MAP2_VERTEX_3 , in the same
manner. If neither a three- nor a four-component vertex map is enabled for the
specified dimension, the gl:evalCoord command is ignored.
If you have enabled automatic normal generation, by calling gl:enable/1 with
argument ?GL_AUTO_NORMAL, gl:evalCoord2 generates surface normals analytically,
regardless of the contents or enabling of the ?GL_MAP2_NORMAL map. Let
m=((∂ p)/(∂ u))×((∂ p)/(∂ v))
Then the generated normal n is n=m/(||m||)
If automatic normal generation is disabled, the corresponding normal map
?GL_MAP2_NORMAL , if enabled, is used to produce a normal. If neither automatic
normal generation nor a normal map is enabled, no normal is generated for
gl:evalCoord2 commands.
See external documentation.
evalCoord1f(U) -> ok
Types:
U = float()
See evalCoord1d/1
evalCoord1dv(U) -> ok
Types:
U = {U::float()}
Equivalent to evalCoord1d(U).
evalCoord1fv(U) -> ok
Types:
U = {U::float()}
Equivalent to evalCoord1f(U).
evalCoord2d(U, V) -> ok
Types:
U = float()
V = float()
See evalCoord1d/1
evalCoord2f(U, V) -> ok
Types:
U = float()
V = float()
See evalCoord1d/1
evalCoord2dv(U) -> ok
Types:
U = {U::float(), V::float()}
Equivalent to evalCoord2d(U, V).
evalCoord2fv(U) -> ok
Types:
U = {U::float(), V::float()}
Equivalent to evalCoord2f(U, V).
mapGrid1d(Un, U1, U2) -> ok
Types:
Un = integer()
U1 = float()
U2 = float()
Define a one- or two-dimensional mesh
gl:mapGrid and gl:evalMesh1/3 are used together to efficiently generate and
evaluate a series of evenly-spaced map domain values. gl:evalMesh1/3 steps through
the integer domain of a one- or two-dimensional grid, whose range is the domain of
the evaluation maps specified by gl:map1d/6 and gl:map1d/6 .
gl:mapGrid1 and gl:mapGrid2 specify the linear grid mappings between the i (or i
and j) integer grid coordinates, to the u (or u and v) floating-point evaluation
map coordinates. See gl:map1d/6 and gl:map1d/6 for details of how u and v
coordinates are evaluated.
gl:mapGrid1 specifies a single linear mapping such that integer grid coordinate 0
maps exactly to U1 , and integer grid coordinate Un maps exactly to U2 . All other
integer grid coordinates i are mapped so that
u=i(u2-u1)/un+u1
gl:mapGrid2 specifies two such linear mappings. One maps integer grid coordinate
i=0 exactly to U1 , and integer grid coordinate i=un exactly to U2 . The other maps
integer grid coordinate j=0 exactly to V1 , and integer grid coordinate j=vn
exactly to V2 . Other integer grid coordinates i and j are mapped such that
u=i(u2-u1)/un+u1
v=j(v2-v1)/vn+v1
The mappings specified by gl:mapGrid are used identically by gl:evalMesh1/3 and
gl:evalPoint1/1 .
See external documentation.
mapGrid1f(Un, U1, U2) -> ok
Types:
Un = integer()
U1 = float()
U2 = float()
See mapGrid1d/3
mapGrid2d(Un, U1, U2, Vn, V1, V2) -> ok
Types:
Un = integer()
U1 = float()
U2 = float()
Vn = integer()
V1 = float()
V2 = float()
See mapGrid1d/3
mapGrid2f(Un, U1, U2, Vn, V1, V2) -> ok
Types:
Un = integer()
U1 = float()
U2 = float()
Vn = integer()
V1 = float()
V2 = float()
See mapGrid1d/3
evalPoint1(I) -> ok
Types:
I = integer()
Generate and evaluate a single point in a mesh
gl:mapGrid1d/3 and gl:evalMesh1/3 are used in tandem to efficiently generate and
evaluate a series of evenly spaced map domain values. gl:evalPoint can be used to
evaluate a single grid point in the same gridspace that is traversed by
gl:evalMesh1/3 . Calling gl:evalPoint1 is equivalent to calling glEvalCoord1(
i.Δ u+u 1 ); where Δ u=(u 2-u 1)/n
and n, u 1, and u 2 are the arguments to the most recent gl:mapGrid1d/3 command.
The one absolute numeric requirement is that if i=n, then the value computed from
i.Δ u+u 1 is exactly u 2.
In the two-dimensional case, gl:evalPoint2, let
Δ u=(u 2-u 1)/n
Δ v=(v 2-v 1)/m
where n, u 1, u 2, m, v 1, and v 2 are the arguments to the most recent
gl:mapGrid1d/3 command. Then the gl:evalPoint2 command is equivalent to calling
glEvalCoord2( i. Δ u+u 1, j.Δ v+v 1 ); The only absolute numeric
requirements are that if i=n, then the value computed from i.Δ u+u 1 is
exactly u 2, and if j=m, then the value computed from j.Δ v+v 1 is exactly v
2.
See external documentation.
evalPoint2(I, J) -> ok
Types:
I = integer()
J = integer()
See evalPoint1/1
evalMesh1(Mode, I1, I2) -> ok
Types:
Mode = enum()
I1 = integer()
I2 = integer()
Compute a one- or two-dimensional grid of points or lines
gl:mapGrid1d/3 and gl:evalMesh are used in tandem to efficiently generate and
evaluate a series of evenly-spaced map domain values. gl:evalMesh steps through the
integer domain of a one- or two-dimensional grid, whose range is the domain of the
evaluation maps specified by gl:map1d/6 and gl:map1d/6 . Mode determines whether
the resulting vertices are connected as points, lines, or filled polygons.
In the one-dimensional case, gl:evalMesh1, the mesh is generated as if the
following code fragment were executed:
glBegin( Type ); for ( i = I1 ; i <= I2 ; i += 1 ) glEvalCoord1( i.Δ u+u 1 );
glEnd(); where
Δ u=(u 2-u 1)/n
and n, u 1, and u 2 are the arguments to the most recent gl:mapGrid1d/3 command.
type is ?GL_POINTS if Mode is ?GL_POINT, or ?GL_LINES if Mode is ?GL_LINE.
The one absolute numeric requirement is that if i=n, then the value computed from
i.Δ u+u 1 is exactly u 2.
In the two-dimensional case, gl:evalMesh2, let .cp Δ u=(u 2-u 1)/n
Δ v=(v 2-v 1)/m
where n, u 1, u 2, m, v 1, and v 2 are the arguments to the most recent
gl:mapGrid1d/3 command. Then, if Mode is ?GL_FILL, the gl:evalMesh2 command is
equivalent to:
for ( j = J1 ; j < J2 ; j += 1 ) { glBegin( GL_QUAD_STRIP ); for ( i = I1 ; i <= I2
; i += 1 ) { glEvalCoord2( i.Δ u+u 1, j.Δ v+v 1 ); glEvalCoord2(
i.Δ u+u 1,(j+1).Δ v+v 1 ); } glEnd(); }
If Mode is ?GL_LINE, then a call to gl:evalMesh2 is equivalent to:
for ( j = J1 ; j <= J2 ; j += 1 ) { glBegin( GL_LINE_STRIP ); for ( i = I1 ; i <=
I2 ; i += 1 ) glEvalCoord2( i.Δ u+u 1, j.Δ v+v 1 ); glEnd(); } for ( i
= I1 ; i <= I2 ; i += 1 ) { glBegin( GL_LINE_STRIP ); for ( j = J1 ; j <= J1 ; j +=
1 ) glEvalCoord2( i.Δ u+u 1, j. Δ v+v 1 ); glEnd(); }
And finally, if Mode is ?GL_POINT, then a call to gl:evalMesh2 is equivalent to:
glBegin( GL_POINTS ); for ( j = J1 ; j <= J2 ; j += 1 ) for ( i = I1 ; i <= I2 ; i
+= 1 ) glEvalCoord2( i.Δ u+u 1, j.Δ v+v 1 ); glEnd();
In all three cases, the only absolute numeric requirements are that if i=n, then
the value computed from i.Δ u+u 1 is exactly u 2, and if j=m, then the value
computed from j.Δ v+v 1 is exactly v 2.
See external documentation.
evalMesh2(Mode, I1, I2, J1, J2) -> ok
Types:
Mode = enum()
I1 = integer()
I2 = integer()
J1 = integer()
J2 = integer()
See evalMesh1/3
fogf(Pname, Param) -> ok
Types:
Pname = enum()
Param = float()
Specify fog parameters
Fog is initially disabled. While enabled, fog affects rasterized geometry, bitmaps,
and pixel blocks, but not buffer clear operations. To enable and disable fog, call
gl:enable/1 and gl:enable/1 with argument ?GL_FOG.
gl:fog assigns the value or values in Params to the fog parameter specified by
Pname . The following values are accepted for Pname :
?GL_FOG_MODE: Params is a single integer or floating-point value that specifies the
equation to be used to compute the fog blend factor, f. Three symbolic constants
are accepted: ?GL_LINEAR, ?GL_EXP, and ?GL_EXP2. The equations corresponding to
these symbolic constants are defined below. The initial fog mode is ?GL_EXP.
?GL_FOG_DENSITY: Params is a single integer or floating-point value that specifies
density, the fog density used in both exponential fog equations. Only nonnegative
densities are accepted. The initial fog density is 1.
?GL_FOG_START: Params is a single integer or floating-point value that specifies
start, the near distance used in the linear fog equation. The initial near distance
is 0.
?GL_FOG_END: Params is a single integer or floating-point value that specifies end,
the far distance used in the linear fog equation. The initial far distance is 1.
?GL_FOG_INDEX: Params is a single integer or floating-point value that specifies i
f, the fog color index. The initial fog index is 0.
?GL_FOG_COLOR: Params contains four integer or floating-point values that specify C
f, the fog color. Integer values are mapped linearly such that the most positive
representable value maps to 1.0, and the most negative representable value maps to
-1.0. Floating-point values are mapped directly. After conversion, all color
components are clamped to the range [0 1]. The initial fog color is (0, 0, 0, 0).
?GL_FOG_COORD_SRC: Params contains either of the following symbolic constants:
?GL_FOG_COORD or ?GL_FRAGMENT_DEPTH. ?GL_FOG_COORD specifies that the current fog
coordinate should be used as distance value in the fog color computation.
?GL_FRAGMENT_DEPTH specifies that the current fragment depth should be used as
distance value in the fog computation.
Fog blends a fog color with each rasterized pixel fragment's post-texturing color
using a blending factor f. Factor f is computed in one of three ways, depending on
the fog mode. Let c be either the distance in eye coordinate from the origin (in
the case that the ?GL_FOG_COORD_SRC is ?GL_FRAGMENT_DEPTH) or the current fog
coordinate (in the case that ?GL_FOG_COORD_SRC is ?GL_FOG_COORD). The equation for
?GL_LINEAR fog is f=(end-c)/(end-start)
The equation for ?GL_EXP fog is f=e(-(density. c))
The equation for ?GL_EXP2 fog is f=e(-(density. c)) 2
Regardless of the fog mode, f is clamped to the range [0 1] after it is computed.
Then, if the GL is in RGBA color mode, the fragment's red, green, and blue colors,
represented by C r, are replaced by
(C r)"=f×C r+(1-f)×C f
Fog does not affect a fragment's alpha component.
In color index mode, the fragment's color index i r is replaced by
(i r)"=i r+(1-f)×i f
See external documentation.
fogi(Pname, Param) -> ok
Types:
Pname = enum()
Param = integer()
See fogf/2
fogfv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {float()}
See fogf/2
fogiv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {integer()}
See fogf/2
feedbackBuffer(Size, Type, Buffer) -> ok
Types:
Size = integer()
Type = enum()
Buffer = mem()
Controls feedback mode
The gl:feedbackBuffer function controls feedback. Feedback, like selection, is a GL
mode. The mode is selected by calling gl:renderMode/1 with ?GL_FEEDBACK. When the
GL is in feedback mode, no pixels are produced by rasterization. Instead,
information about primitives that would have been rasterized is fed back to the
application using the GL.
gl:feedbackBuffer has three arguments: Buffer is a pointer to an array of floating-
point values into which feedback information is placed. Size indicates the size of
the array. Type is a symbolic constant describing the information that is fed back
for each vertex. gl:feedbackBuffer must be issued before feedback mode is enabled
(by calling gl:renderMode/1 with argument ?GL_FEEDBACK). Setting ?GL_FEEDBACK
without establishing the feedback buffer, or calling gl:feedbackBuffer while the GL
is in feedback mode, is an error.
When gl:renderMode/1 is called while in feedback mode, it returns the number of
entries placed in the feedback array and resets the feedback array pointer to the
base of the feedback buffer. The returned value never exceeds Size . If the
feedback data required more room than was available in Buffer , gl:renderMode/1
returns a negative value. To take the GL out of feedback mode, call gl:renderMode/1
with a parameter value other than ?GL_FEEDBACK.
While in feedback mode, each primitive, bitmap, or pixel rectangle that would be
rasterized generates a block of values that are copied into the feedback array. If
doing so would cause the number of entries to exceed the maximum, the block is
partially written so as to fill the array (if there is any room left at all), and
an overflow flag is set. Each block begins with a code indicating the primitive
type, followed by values that describe the primitive's vertices and associated
data. Entries are also written for bitmaps and pixel rectangles. Feedback occurs
after polygon culling and gl:polygonMode/2 interpretation of polygons has taken
place, so polygons that are culled are not returned in the feedback buffer. It can
also occur after polygons with more than three edges are broken up into triangles,
if the GL implementation renders polygons by performing this decomposition.
The gl:passThrough/1 command can be used to insert a marker into the feedback
buffer. See gl:passThrough/1 .
Following is the grammar for the blocks of values written into the feedback buffer.
Each primitive is indicated with a unique identifying value followed by some number
of vertices. Polygon entries include an integer value indicating how many vertices
follow. A vertex is fed back as some number of floating-point values, as determined
by Type . Colors are fed back as four values in RGBA mode and one value in color
index mode.
feedbackList ← feedbackItem feedbackList | feedbackItem
feedbackItem ← point | lineSegment | polygon | bitmap | pixelRectangle | passThru
point ←?GL_POINT_TOKEN vertex
lineSegment ←?GL_LINE_TOKEN vertex vertex | ?GL_LINE_RESET_TOKEN vertex vertex
polygon ←?GL_POLYGON_TOKEN n polySpec
polySpec ← polySpec vertex | vertex vertex vertex
bitmap ←?GL_BITMAP_TOKEN vertex
pixelRectangle ←?GL_DRAW_PIXEL_TOKEN vertex | ?GL_COPY_PIXEL_TOKEN vertex
passThru ←?GL_PASS_THROUGH_TOKEN value
vertex ← 2d | 3d | 3dColor | 3dColorTexture | 4dColorTexture
2d ← value value
3d ← value value value
3dColor ← value value value color
3dColorTexture ← value value value color tex
4dColorTexture ← value value value value color tex
color ← rgba | index
rgba ← value value value value
index ← value
tex ← value value value value
value is a floating-point number, and n is a floating-point integer giving the
number of vertices in the polygon. ?GL_POINT_TOKEN, ?GL_LINE_TOKEN,
?GL_LINE_RESET_TOKEN , ?GL_POLYGON_TOKEN, ?GL_BITMAP_TOKEN, ?GL_DRAW_PIXEL_TOKEN,
?GL_COPY_PIXEL_TOKEN and ?GL_PASS_THROUGH_TOKEN are symbolic floating-point
constants. ?GL_LINE_RESET_TOKEN is returned whenever the line stipple pattern is
reset. The data returned as a vertex depends on the feedback Type .
The following table gives the correspondence between Type and the number of values
per vertex. k is 1 in color index mode and 4 in RGBA
mode.TypeCoordinatesColorTextureTotal Number of Values
?GL_2Dx, y 2
?GL_3Dx, y, z 3
?GL_3D_COLORx, y, z k 3+k
?GL_3D_COLOR_TEXTUREx, y, z k 4 7+k
?GL_4D_COLOR_TEXTUREx, y, z, w k 4 8+k
Feedback vertex coordinates are in window coordinates, except w, which is in clip
coordinates. Feedback colors are lighted, if lighting is enabled. Feedback texture
coordinates are generated, if texture coordinate generation is enabled. They are
always transformed by the texture matrix.
See external documentation.
passThrough(Token) -> ok
Types:
Token = float()
Place a marker in the feedback buffer
Feedback is a GL render mode. The mode is selected by calling gl:renderMode/1 with
?GL_FEEDBACK. When the GL is in feedback mode, no pixels are produced by
rasterization. Instead, information about primitives that would have been
rasterized is fed back to the application using the GL. See the gl:feedbackBuffer/3
reference page for a description of the feedback buffer and the values in it.
gl:passThrough inserts a user-defined marker in the feedback buffer when it is
executed in feedback mode. Token is returned as if it were a primitive; it is
indicated with its own unique identifying value: ?GL_PASS_THROUGH_TOKEN. The order
of gl:passThrough commands with respect to the specification of graphics primitives
is maintained.
See external documentation.
selectBuffer(Size, Buffer) -> ok
Types:
Size = integer()
Buffer = mem()
Establish a buffer for selection mode values
gl:selectBuffer has two arguments: Buffer is a pointer to an array of unsigned
integers, and Size indicates the size of the array. Buffer returns values from the
name stack (see gl:initNames/0 , gl:loadName/1 , gl:pushName/1 ) when the rendering
mode is ?GL_SELECT (see gl:renderMode/1 ). gl:selectBuffer must be issued before
selection mode is enabled, and it must not be issued while the rendering mode is
?GL_SELECT.
A programmer can use selection to determine which primitives are drawn into some
region of a window. The region is defined by the current modelview and perspective
matrices.
In selection mode, no pixel fragments are produced from rasterization. Instead, if
a primitive or a raster position intersects the clipping volume defined by the
viewing frustum and the user-defined clipping planes, this primitive causes a
selection hit. (With polygons, no hit occurs if the polygon is culled.) When a
change is made to the name stack, or when gl:renderMode/1 is called, a hit record
is copied to Buffer if any hits have occurred since the last such event (name stack
change or gl:renderMode/1 call). The hit record consists of the number of names in
the name stack at the time of the event, followed by the minimum and maximum depth
values of all vertices that hit since the previous event, followed by the name
stack contents, bottom name first.
Depth values (which are in the range [0,1]) are multiplied by 2 32-1, before being
placed in the hit record.
An internal index into Buffer is reset to 0 whenever selection mode is entered.
Each time a hit record is copied into Buffer , the index is incremented to point to
the cell just past the end of the block of names(emthat is, to the next available
cell If the hit record is larger than the number of remaining locations in Buffer ,
as much data as can fit is copied, and the overflow flag is set. If the name stack
is empty when a hit record is copied, that record consists of 0 followed by the
minimum and maximum depth values.
To exit selection mode, call gl:renderMode/1 with an argument other than ?GL_SELECT
. Whenever gl:renderMode/1 is called while the render mode is ?GL_SELECT, it
returns the number of hit records copied to Buffer , resets the overflow flag and
the selection buffer pointer, and initializes the name stack to be empty. If the
overflow bit was set when gl:renderMode/1 was called, a negative hit record count
is returned.
See external documentation.
initNames() -> ok
Initialize the name stack
The name stack is used during selection mode to allow sets of rendering commands to
be uniquely identified. It consists of an ordered set of unsigned integers.
gl:initNames causes the name stack to be initialized to its default empty state.
The name stack is always empty while the render mode is not ?GL_SELECT. Calls to
gl:initNames while the render mode is not ?GL_SELECT are ignored.
See external documentation.
loadName(Name) -> ok
Types:
Name = integer()
Load a name onto the name stack
The name stack is used during selection mode to allow sets of rendering commands to
be uniquely identified. It consists of an ordered set of unsigned integers and is
initially empty.
gl:loadName causes Name to replace the value on the top of the name stack.
The name stack is always empty while the render mode is not ?GL_SELECT. Calls to
gl:loadName while the render mode is not ?GL_SELECT are ignored.
See external documentation.
pushName(Name) -> ok
Types:
Name = integer()
Push and pop the name stack
The name stack is used during selection mode to allow sets of rendering commands to
be uniquely identified. It consists of an ordered set of unsigned integers and is
initially empty.
gl:pushName causes Name to be pushed onto the name stack. gl:pushName/1 pops one
name off the top of the stack.
The maximum name stack depth is implementation-dependent; call
?GL_MAX_NAME_STACK_DEPTH to find out the value for a particular implementation. It
is an error to push a name onto a full stack or to pop a name off an empty stack.
It is also an error to manipulate the name stack between the execution of
gl:'begin'/1 and the corresponding execution of gl:'begin'/1 . In any of these
cases, the error flag is set and no other change is made to GL state.
The name stack is always empty while the render mode is not ?GL_SELECT. Calls to
gl:pushName or gl:pushName/1 while the render mode is not ?GL_SELECT are ignored.
See external documentation.
popName() -> ok
See pushName/1
blendColor(Red, Green, Blue, Alpha) -> ok
Types:
Red = clamp()
Green = clamp()
Blue = clamp()
Alpha = clamp()
Set the blend color
The ?GL_BLEND_COLOR may be used to calculate the source and destination blending
factors. The color components are clamped to the range [0 1] before being stored.
See gl:blendFunc/2 for a complete description of the blending operations. Initially
the ?GL_BLEND_COLOR is set to (0, 0, 0, 0).
See external documentation.
blendEquation(Mode) -> ok
Types:
Mode = enum()
Specify the equation used for both the RGB blend equation and the Alpha blend
equation
The blend equations determine how a new pixel (the ''source'' color) is combined
with a pixel already in the framebuffer (the ''destination'' color). This function
sets both the RGB blend equation and the alpha blend equation to a single equation.
gl:blendEquationi specifies the blend equation for a single draw buffer whereas
gl:blendEquation sets the blend equation for all draw buffers.
These equations use the source and destination blend factors specified by either
gl:blendFunc/2 or gl:blendFuncSeparate/4 . See gl:blendFunc/2 or
gl:blendFuncSeparate/4 for a description of the various blend factors.
In the equations that follow, source and destination color components are referred
to as (R s G s B s A s) and (R d G d B d A d), respectively. The result color is
referred to as (R r G r B r A r). The source and destination blend factors are
denoted (s R s G s B s A) and (d R d G d B d A), respectively. For these equations
all color components are understood to have values in the range [0 1].ModeRGB
ComponentsAlpha Component
?GL_FUNC_ADD Rr=R s s R+R d d R Gr=G s s G+G d d G Br=B s s B+B d d B Ar=A s s A+A
d d A
?GL_FUNC_SUBTRACT Rr=R s s R-R d d R Gr=G s s G-G d d G Br=B s s B-B d d B Ar=A s s
A-A d d A
?GL_FUNC_REVERSE_SUBTRACT Rr=R d d R-R s s R Gr=G d d G-G s s G Br=B d d B-B s s B
Ar=A d d A-A s s A
?GL_MIN Rr=min(R s R d) Gr=min(G s G d) Br=min(B s B d) Ar=min (A s A d)
?GL_MAX Rr=max(R s R d) Gr=max(G s G d) Br=max(B s B d) Ar=max(A s A d)
The results of these equations are clamped to the range [0 1].
The ?GL_MIN and ?GL_MAX equations are useful for applications that analyze image
data (image thresholding against a constant color, for example). The ?GL_FUNC_ADD
equation is useful for antialiasing and transparency, among other things.
Initially, both the RGB blend equation and the alpha blend equation are set to
?GL_FUNC_ADD .
See external documentation.
drawRangeElements(Mode, Start, End, Count, Type, Indices) -> ok
Types:
Mode = enum()
Start = integer()
End = integer()
Count = integer()
Type = enum()
Indices = offset() | mem()
Render primitives from array data
gl:drawRangeElements is a restricted form of gl:drawElements/4 . Mode , Start , End
, and Count match the corresponding arguments to gl:drawElements/4 , with the
additional constraint that all values in the arrays Count must lie between Start
and End , inclusive.
Implementations denote recommended maximum amounts of vertex and index data, which
may be queried by calling gl:getBooleanv/1 with argument ?GL_MAX_ELEMENTS_VERTICES
and ?GL_MAX_ELEMENTS_INDICES . If end-start+1 is greater than the value of
?GL_MAX_ELEMENTS_VERTICES, or if Count is greater than the value of
?GL_MAX_ELEMENTS_INDICES, then the call may operate at reduced performance. There
is no requirement that all vertices in the range [start end] be referenced.
However, the implementation may partially process unused vertices, reducing
performance from what could be achieved with an optimal index set.
When gl:drawRangeElements is called, it uses Count sequential elements from an
enabled array, starting at Start to construct a sequence of geometric primitives.
Mode specifies what kind of primitives are constructed, and how the array elements
construct these primitives. If more than one array is enabled, each is used.
Vertex attributes that are modified by gl:drawRangeElements have an unspecified
value after gl:drawRangeElements returns. Attributes that aren't modified maintain
their previous values.
See external documentation.
texImage3D(Target, Level, InternalFormat, Width, Height, Depth, Border, Format, Type,
Pixels) -> ok
Types:
Target = enum()
Level = integer()
InternalFormat = integer()
Width = integer()
Height = integer()
Depth = integer()
Border = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
Specify a three-dimensional texture image
Texturing maps a portion of a specified texture image onto each graphical primitive
for which texturing is enabled. To enable and disable three-dimensional texturing,
call gl:enable/1 and gl:enable/1 with argument ?GL_TEXTURE_3D.
To define texture images, call gl:texImage3D. The arguments describe the parameters
of the texture image, such as height, width, depth, width of the border, level-of-
detail number (see gl:texParameterf/3 ), and number of color components provided.
The last three arguments describe how the image is represented in memory.
If Target is ?GL_PROXY_TEXTURE_3D, no data is read from Data , but all of the
texture image state is recalculated, checked for consistency, and checked against
the implementation's capabilities. If the implementation cannot handle a texture of
the requested texture size, it sets all of the image state to 0, but does not
generate an error (see gl:getError/0 ). To query for an entire mipmap array, use an
image array level greater than or equal to 1.
If Target is ?GL_TEXTURE_3D, data is read from Data as a sequence of signed or
unsigned bytes, shorts, or longs, or single-precision floating-point values,
depending on Type . These values are grouped into sets of one, two, three, or four
values, depending on Format , to form elements. Each data byte is treated as eight
1-bit elements, with bit ordering determined by ?GL_UNPACK_LSB_FIRST (see
gl:pixelStoref/2 ).
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
The first element corresponds to the lower left corner of the texture image.
Subsequent elements progress left-to-right through the remaining texels in the
lowest row of the texture image, and then in successively higher rows of the
texture image. The final element corresponds to the upper right corner of the
texture image.
Format determines the composition of each element in Data . It can assume one of
these symbolic values:
?GL_RED: Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and blue, and
1 for alpha. Each component is then multiplied by the signed scale factor
?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RG: Each element is a red and green pair. The GL converts each to floating
point and assembles it into an RGBA element by attaching 0 for blue, and 1 for
alpha. Each component is then multiplied by the signed scale factor ?GL_c_SCALE,
added to the signed bias ?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGB
?GL_BGR: Each element is an RGB triple. The GL converts it to floating point and
assembles it into an RGBA element by attaching 1 for alpha. Each component is then
multiplied by the signed scale factor ?GL_c_SCALE, added to the signed bias
?GL_c_BIAS, and clamped to the range [0,1].
?GL_RGBA
?GL_BGRA: Each element contains all four components. Each component is multiplied
by the signed scale factor ?GL_c_SCALE, added to the signed bias ?GL_c_BIAS, and
clamped to the range [0,1].
If an application wants to store the texture at a certain resolution or in a
certain format, it can request the resolution and format with InternalFormat . The
GL will choose an internal representation that closely approximates that requested
by InternalFormat , but it may not match exactly. (The representations specified by
?GL_RED, ?GL_RG , ?GL_RGB, and ?GL_RGBA must match exactly.)
InternalFormat may be one of the base internal formats shown in Table 1, below
InternalFormat may also be one of the sized internal formats shown in Table 2,
below
Finally, InternalFormat may also be one of the generic or compressed compressed
texture formats shown in Table 3 below
If the InternalFormat parameter is one of the generic compressed formats,
?GL_COMPRESSED_RED , ?GL_COMPRESSED_RG, ?GL_COMPRESSED_RGB, or ?GL_COMPRESSED_RGBA,
the GL will replace the internal format with the symbolic constant for a specific
internal format and compress the texture before storage. If no corresponding
internal format is available, or the GL can not compress that image for any reason,
the internal format is instead replaced with a corresponding base internal format.
If the InternalFormat parameter is ?GL_SRGB, ?GL_SRGB8, ?GL_SRGB_ALPHA , or
?GL_SRGB8_ALPHA8, the texture is treated as if the red, green, blue, or luminance
components are encoded in the sRGB color space. Any alpha component is left
unchanged. The conversion from the sRGB encoded component c s to a linear component
c l is:
c l={ c s/12.92if c s≤ 0.04045( c s+0.055/1.055) 2.4if c s> 0.04045
Assume c s is the sRGB component in the range [0,1].
Use the ?GL_PROXY_TEXTURE_3D target to try out a resolution and format. The
implementation will update and recompute its best match for the requested storage
resolution and format. To then query this state, call gl:getTexLevelParameterfv/3 .
If the texture cannot be accommodated, texture state is set to 0.
A one-component texture image uses only the red component of the RGBA color
extracted from Data . A two-component image uses the R and A values. A three-
component image uses the R, G, and B values. A four-component image uses all of the
RGBA components.
See external documentation.
texSubImage3D(Target, Level, Xoffset, Yoffset, Zoffset, Width, Height, Depth, Format,
Type, Pixels) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
Zoffset = integer()
Width = integer()
Height = integer()
Depth = integer()
Format = enum()
Type = enum()
Pixels = offset() | mem()
glTexSubImage
See external documentation.
copyTexSubImage3D(Target, Level, Xoffset, Yoffset, Zoffset, X, Y, Width, Height) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
Zoffset = integer()
X = integer()
Y = integer()
Width = integer()
Height = integer()
Copy a three-dimensional texture subimage
gl:copyTexSubImage3D replaces a rectangular portion of a three-dimensional texture
image with pixels from the current ?GL_READ_BUFFER (rather than from main memory,
as is the case for gl:texSubImage1D/7 ).
The screen-aligned pixel rectangle with lower left corner at ( X , Y ) and with
width Width and height Height replaces the portion of the texture array with x
indices Xoffset through xoffset+width-1, inclusive, and y indices Yoffset through
yoffset+height-1, inclusive, at z index Zoffset and at the mipmap level specified
by Level .
The pixels in the rectangle are processed exactly as if gl:readPixels/7 had been
called, but the process stops just before final conversion. At this point, all
pixel component values are clamped to the range [0 1] and then converted to the
texture's internal format for storage in the texel array.
The destination rectangle in the texture array may not include any texels outside
the texture array as it was originally specified. It is not an error to specify a
subtexture with zero width or height, but such a specification has no effect.
If any of the pixels within the specified rectangle of the current ?GL_READ_BUFFER
are outside the read window associated with the current rendering context, then the
values obtained for those pixels are undefined.
No change is made to the internalformat, width, height, depth, or border parameters
of the specified texture array or to texel values outside the specified subregion.
See external documentation.
colorTable(Target, Internalformat, Width, Format, Type, Table) -> ok
Types:
Target = enum()
Internalformat = enum()
Width = integer()
Format = enum()
Type = enum()
Table = offset() | mem()
Define a color lookup table
gl:colorTable may be used in two ways: to test the actual size and color resolution
of a lookup table given a particular set of parameters, or to load the contents of
a color lookup table. Use the targets ?GL_PROXY_* for the first case and the other
targets for the second case.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a color table is specified, Data is treated as a byte
offset into the buffer object's data store.
If Target is ?GL_COLOR_TABLE, ?GL_POST_CONVOLUTION_COLOR_TABLE, or
?GL_POST_COLOR_MATRIX_COLOR_TABLE , gl:colorTable builds a color lookup table from
an array of pixels. The pixel array specified by Width , Format , Type , and Data
is extracted from memory and processed just as if gl:drawPixels/5 were called, but
processing stops after the final expansion to RGBA is completed.
The four scale parameters and the four bias parameters that are defined for the
table are then used to scale and bias the R, G, B, and A components of each pixel.
(Use gl:colorTableParameter to set these scale and bias parameters.)
Next, the R, G, B, and A values are clamped to the range [0 1]. Each pixel is then
converted to the internal format specified by Internalformat . This conversion
simply maps the component values of the pixel (R, G, B, and A) to the values
included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
Finally, the red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in the color table. They form a one-dimensional table
with indices in the range [0 width-1].
If Target is ?GL_PROXY_*, gl:colorTable recomputes and stores the values of the
proxy color table's state variables ?GL_COLOR_TABLE_FORMAT, ?GL_COLOR_TABLE_WIDTH ,
?GL_COLOR_TABLE_RED_SIZE, ?GL_COLOR_TABLE_GREEN_SIZE, ?GL_COLOR_TABLE_BLUE_SIZE ,
?GL_COLOR_TABLE_ALPHA_SIZE, ?GL_COLOR_TABLE_LUMINANCE_SIZE, and
?GL_COLOR_TABLE_INTENSITY_SIZE . There is no effect on the image or state of any
actual color table. If the specified color table is too large to be supported, then
all the proxy state variables listed above are set to zero. Otherwise, the color
table could be supported by gl:colorTable using the corresponding non-proxy target,
and the proxy state variables are set as if that target were being defined.
The proxy state variables can be retrieved by calling gl:getColorTableParameterfv/2
with a target of ?GL_PROXY_*. This allows the application to decide if a particular
gl:colorTable command would succeed, and to determine what the resulting color
table attributes would be.
If a color table is enabled, and its width is non-zero, then its contents are used
to replace a subset of the components of each RGBA pixel group, based on the
internal format of the table.
Each pixel group has color components (R, G, B, A) that are in the range [0.0 1.0].
The color components are rescaled to the size of the color lookup table to form an
index. Then a subset of the components based on the internal format of the table
are replaced by the table entry selected by that index. If the color components and
contents of the table are represented as follows:RepresentationMeaning
r Table index computed from R
g Table index computed from G
b Table index computed from B
a Table index computed from A
L[i] Luminance value at table index i
I[i] Intensity value at table index i
R[i] Red value at table index i
G[i] Green value at table index i
B[i] Blue value at table index i
A[i] Alpha value at table index i
then the result of color table lookup is as follows:Resulting Texture Components
Table Internal FormatRGBA
?GL_ALPHARGBA[a]
?GL_LUMINANCEL[r]L[g]L[b]At
?GL_LUMINANCE_ALPHA L[r]L[g]L[b]A[a]
?GL_INTENSITY I[r]I[g]I[b]I[a]
?GL_RGBR[r] G[g]B[b]A
?GL_RGBAR[r] G[g]B[b]A[a]
When ?GL_COLOR_TABLE is enabled, the colors resulting from the pixel map operation
(if it is enabled) are mapped by the color lookup table before being passed to the
convolution operation. The colors resulting from the convolution operation are
modified by the post convolution color lookup table when
?GL_POST_CONVOLUTION_COLOR_TABLE is enabled. These modified colors are then sent to
the color matrix operation. Finally, if ?GL_POST_COLOR_MATRIX_COLOR_TABLE is
enabled, the colors resulting from the color matrix operation are mapped by the
post color matrix color lookup table before being used by the histogram operation.
See external documentation.
colorTableParameterfv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {float(), float(), float(), float()}
Set color lookup table parameters
gl:colorTableParameter is used to specify the scale factors and bias terms applied
to color components when they are loaded into a color table. Target indicates which
color table the scale and bias terms apply to; it must be set to ?GL_COLOR_TABLE,
?GL_POST_CONVOLUTION_COLOR_TABLE , or ?GL_POST_COLOR_MATRIX_COLOR_TABLE.
Pname must be ?GL_COLOR_TABLE_SCALE to set the scale factors. In this case, Params
points to an array of four values, which are the scale factors for red, green,
blue, and alpha, in that order.
Pname must be ?GL_COLOR_TABLE_BIAS to set the bias terms. In this case, Params
points to an array of four values, which are the bias terms for red, green, blue,
and alpha, in that order.
The color tables themselves are specified by calling gl:colorTable/6 .
See external documentation.
colorTableParameteriv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer(), integer(), integer(), integer()}
See colorTableParameterfv/3
copyColorTable(Target, Internalformat, X, Y, Width) -> ok
Types:
Target = enum()
Internalformat = enum()
X = integer()
Y = integer()
Width = integer()
Copy pixels into a color table
gl:copyColorTable loads a color table with pixels from the current ?GL_READ_BUFFER
(rather than from main memory, as is the case for gl:colorTable/6 ).
The screen-aligned pixel rectangle with lower-left corner at ( X , Y ) having width
Width and height 1 is loaded into the color table. If any pixels within this region
are outside the window that is associated with the GL context, the values obtained
for those pixels are undefined.
The pixels in the rectangle are processed just as if gl:readPixels/7 were called,
with Internalformat set to RGBA, but processing stops after the final conversion to
RGBA.
The four scale parameters and the four bias parameters that are defined for the
table are then used to scale and bias the R, G, B, and A components of each pixel.
The scale and bias parameters are set by calling gl:colorTableParameterfv/3 .
Next, the R, G, B, and A values are clamped to the range [0 1]. Each pixel is then
converted to the internal format specified by Internalformat . This conversion
simply maps the component values of the pixel (R, G, B, and A) to the values
included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
Finally, the red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in the color table. They form a one-dimensional table
with indices in the range [0 width-1].
See external documentation.
getColorTable(Target, Format, Type, Table) -> ok
Types:
Target = enum()
Format = enum()
Type = enum()
Table = mem()
Retrieve contents of a color lookup table
gl:getColorTable returns in Table the contents of the color table specified by
Target . No pixel transfer operations are performed, but pixel storage modes that
are applicable to gl:readPixels/7 are performed.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a histogram table is requested, Table is treated as a byte
offset into the buffer object's data store.
Color components that are requested in the specified Format , but which are not
included in the internal format of the color lookup table, are returned as zero.
The assignments of internal color components to the components requested by Format
areInternal ComponentResulting Component
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
Intensity Red
See external documentation.
getColorTableParameterfv(Target, Pname) -> {float(), float(), float(), float()}
Types:
Target = enum()
Pname = enum()
Get color lookup table parameters
Returns parameters specific to color table Target .
When Pname is set to ?GL_COLOR_TABLE_SCALE or ?GL_COLOR_TABLE_BIAS,
gl:getColorTableParameter returns the color table scale or bias parameters for the
table specified by Target . For these queries, Target must be set to
?GL_COLOR_TABLE , ?GL_POST_CONVOLUTION_COLOR_TABLE, or
?GL_POST_COLOR_MATRIX_COLOR_TABLE and Params points to an array of four elements,
which receive the scale or bias factors for red, green, blue, and alpha, in that
order.
gl:getColorTableParameter can also be used to retrieve the format and size
parameters for a color table. For these queries, set Target to either the color
table target or the proxy color table target. The format and size parameters are
set by gl:colorTable/6 .
The following table lists the format and size parameters that may be queried. For
each symbolic constant listed below for Pname , Params must point to an array of
the given length and receive the values indicated.ParameterNMeaning
?GL_COLOR_TABLE_FORMAT 1 Internal format (e.g., ?GL_RGBA)
?GL_COLOR_TABLE_WIDTH 1 Number of elements in table
?GL_COLOR_TABLE_RED_SIZE 1 Size of red component, in bits
?GL_COLOR_TABLE_GREEN_SIZE 1 Size of green component
?GL_COLOR_TABLE_BLUE_SIZE 1 Size of blue component
?GL_COLOR_TABLE_ALPHA_SIZE 1 Size of alpha component
?GL_COLOR_TABLE_LUMINANCE_SIZE 1 Size of luminance component
?GL_COLOR_TABLE_INTENSITY_SIZE 1 Size of intensity component
See external documentation.
getColorTableParameteriv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
See getColorTableParameterfv/2
colorSubTable(Target, Start, Count, Format, Type, Data) -> ok
Types:
Target = enum()
Start = integer()
Count = integer()
Format = enum()
Type = enum()
Data = offset() | mem()
Respecify a portion of a color table
gl:colorSubTable is used to respecify a contiguous portion of a color table
previously defined using gl:colorTable/6 . The pixels referenced by Data replace
the portion of the existing table from indices Start to start+count-1, inclusive.
This region may not include any entries outside the range of the color table as it
was originally specified. It is not an error to specify a subtexture with width of
0, but such a specification has no effect.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a portion of a color table is respecified, Data is
treated as a byte offset into the buffer object's data store.
See external documentation.
copyColorSubTable(Target, Start, X, Y, Width) -> ok
Types:
Target = enum()
Start = integer()
X = integer()
Y = integer()
Width = integer()
Respecify a portion of a color table
gl:copyColorSubTable is used to respecify a contiguous portion of a color table
previously defined using gl:colorTable/6 . The pixels copied from the framebuffer
replace the portion of the existing table from indices Start to start+x-1,
inclusive. This region may not include any entries outside the range of the color
table, as was originally specified. It is not an error to specify a subtexture with
width of 0, but such a specification has no effect.
See external documentation.
convolutionFilter1D(Target, Internalformat, Width, Format, Type, Image) -> ok
Types:
Target = enum()
Internalformat = enum()
Width = integer()
Format = enum()
Type = enum()
Image = offset() | mem()
Define a one-dimensional convolution filter
gl:convolutionFilter1D builds a one-dimensional convolution filter kernel from an
array of pixels.
The pixel array specified by Width , Format , Type , and Data is extracted from
memory and processed just as if gl:drawPixels/5 were called, but processing stops
after the final expansion to RGBA is completed.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a convolution filter is specified, Data is treated as
a byte offset into the buffer object's data store.
The R, G, B, and A components of each pixel are next scaled by the four 1D
?GL_CONVOLUTION_FILTER_SCALE parameters and biased by the four 1D
?GL_CONVOLUTION_FILTER_BIAS parameters. (The scale and bias parameters are set by
gl:convolutionParameterf/3 using the ?GL_CONVOLUTION_1D target and the names
?GL_CONVOLUTION_FILTER_SCALE and ?GL_CONVOLUTION_FILTER_BIAS . The parameters
themselves are vectors of four values that are applied to red, green, blue, and
alpha, in that order.) The R, G, B, and A values are not clamped to [0,1] at any
time during this process.
Each pixel is then converted to the internal format specified by Internalformat .
This conversion simply maps the component values of the pixel (R, G, B, and A) to
the values included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
The red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in floating-point rather than integer format. They form
a one-dimensional filter kernel image indexed with coordinate i such that i starts
at 0 and increases from left to right. Kernel location i is derived from the ith
pixel, counting from 0.
Note that after a convolution is performed, the resulting color components are also
scaled by their corresponding ?GL_POST_CONVOLUTION_c_SCALE parameters and biased by
their corresponding ?GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the
values RED, GREEN, BLUE, and ALPHA). These parameters are set by
gl:pixelTransferf/2 .
See external documentation.
convolutionFilter2D(Target, Internalformat, Width, Height, Format, Type, Image) -> ok
Types:
Target = enum()
Internalformat = enum()
Width = integer()
Height = integer()
Format = enum()
Type = enum()
Image = offset() | mem()
Define a two-dimensional convolution filter
gl:convolutionFilter2D builds a two-dimensional convolution filter kernel from an
array of pixels.
The pixel array specified by Width , Height , Format , Type , and Data is extracted
from memory and processed just as if gl:drawPixels/5 were called, but processing
stops after the final expansion to RGBA is completed.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a convolution filter is specified, Data is treated as
a byte offset into the buffer object's data store.
The R, G, B, and A components of each pixel are next scaled by the four 2D
?GL_CONVOLUTION_FILTER_SCALE parameters and biased by the four 2D
?GL_CONVOLUTION_FILTER_BIAS parameters. (The scale and bias parameters are set by
gl:convolutionParameterf/3 using the ?GL_CONVOLUTION_2D target and the names
?GL_CONVOLUTION_FILTER_SCALE and ?GL_CONVOLUTION_FILTER_BIAS . The parameters
themselves are vectors of four values that are applied to red, green, blue, and
alpha, in that order.) The R, G, B, and A values are not clamped to [0,1] at any
time during this process.
Each pixel is then converted to the internal format specified by Internalformat .
This conversion simply maps the component values of the pixel (R, G, B, and A) to
the values included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
The red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in floating-point rather than integer format. They form
a two-dimensional filter kernel image indexed with coordinates i and j such that i
starts at zero and increases from left to right, and j starts at zero and increases
from bottom to top. Kernel location i,j is derived from the Nth pixel, where N is
i+j* Width .
Note that after a convolution is performed, the resulting color components are also
scaled by their corresponding ?GL_POST_CONVOLUTION_c_SCALE parameters and biased by
their corresponding ?GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the
values RED, GREEN, BLUE, and ALPHA). These parameters are set by
gl:pixelTransferf/2 .
See external documentation.
convolutionParameterf(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {float()}
Set convolution parameters
gl:convolutionParameter sets the value of a convolution parameter.
Target selects the convolution filter to be affected: ?GL_CONVOLUTION_1D,
?GL_CONVOLUTION_2D , or ?GL_SEPARABLE_2D for the 1D, 2D, or separable 2D filter,
respectively.
Pname selects the parameter to be changed. ?GL_CONVOLUTION_FILTER_SCALE and
?GL_CONVOLUTION_FILTER_BIAS affect the definition of the convolution filter kernel;
see gl:convolutionFilter1D/6 , gl:convolutionFilter2D/7 , and
gl:separableFilter2D/8 for details. In these cases, Params v is an array of four
values to be applied to red, green, blue, and alpha values, respectively. The
initial value for ?GL_CONVOLUTION_FILTER_SCALE is (1, 1, 1, 1), and the initial
value for ?GL_CONVOLUTION_FILTER_BIAS is (0, 0, 0, 0).
A Pname value of ?GL_CONVOLUTION_BORDER_MODE controls the convolution border mode.
The accepted modes are:
?GL_REDUCE: The image resulting from convolution is smaller than the source image.
If the filter width is Wf and height is Hf, and the source image width is Ws and
height is Hs, then the convolved image width will be Ws-Wf+1 and height will be Hs-
Hf +1. (If this reduction would generate an image with zero or negative width
and/or height, the output is simply null, with no error generated.) The coordinates
of the image resulting from convolution are zero through Ws-Wf in width and zero
through Hs-Hf in height.
?GL_CONSTANT_BORDER: The image resulting from convolution is the same size as the
source image, and processed as if the source image were surrounded by pixels with
their color specified by the ?GL_CONVOLUTION_BORDER_COLOR.
?GL_REPLICATE_BORDER: The image resulting from convolution is the same size as the
source image, and processed as if the outermost pixel on the border of the source
image were replicated.
See external documentation.
convolutionParameterfv(Target::enum(), Pname::enum(), Params) -> ok
Types:
Params = {Params::{float()}}
Equivalent to convolutionParameterf(Target, Pname, Params).
convolutionParameteri(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer()}
See convolutionParameterf/3
convolutionParameteriv(Target::enum(), Pname::enum(), Params) -> ok
Types:
Params = {Params::{integer()}}
Equivalent to convolutionParameteri(Target, Pname, Params).
copyConvolutionFilter1D(Target, Internalformat, X, Y, Width) -> ok
Types:
Target = enum()
Internalformat = enum()
X = integer()
Y = integer()
Width = integer()
Copy pixels into a one-dimensional convolution filter
gl:copyConvolutionFilter1D defines a one-dimensional convolution filter kernel with
pixels from the current ?GL_READ_BUFFER (rather than from main memory, as is the
case for gl:convolutionFilter1D/6 ).
The screen-aligned pixel rectangle with lower-left corner at ( X , Y ), width Width
and height 1 is used to define the convolution filter. If any pixels within this
region are outside the window that is associated with the GL context, the values
obtained for those pixels are undefined.
The pixels in the rectangle are processed exactly as if gl:readPixels/7 had been
called with format set to RGBA, but the process stops just before final conversion.
The R, G, B, and A components of each pixel are next scaled by the four 1D
?GL_CONVOLUTION_FILTER_SCALE parameters and biased by the four 1D
?GL_CONVOLUTION_FILTER_BIAS parameters. (The scale and bias parameters are set by
gl:convolutionParameterf/3 using the ?GL_CONVOLUTION_1D target and the names
?GL_CONVOLUTION_FILTER_SCALE and ?GL_CONVOLUTION_FILTER_BIAS . The parameters
themselves are vectors of four values that are applied to red, green, blue, and
alpha, in that order.) The R, G, B, and A values are not clamped to [0,1] at any
time during this process.
Each pixel is then converted to the internal format specified by Internalformat .
This conversion simply maps the component values of the pixel (R, G, B, and A) to
the values included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
The red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in floating-point rather than integer format.
Pixel ordering is such that lower x screen coordinates correspond to lower i filter
image coordinates.
Note that after a convolution is performed, the resulting color components are also
scaled by their corresponding ?GL_POST_CONVOLUTION_c_SCALE parameters and biased by
their corresponding ?GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the
values RED, GREEN, BLUE, and ALPHA). These parameters are set by
gl:pixelTransferf/2 .
See external documentation.
copyConvolutionFilter2D(Target, Internalformat, X, Y, Width, Height) -> ok
Types:
Target = enum()
Internalformat = enum()
X = integer()
Y = integer()
Width = integer()
Height = integer()
Copy pixels into a two-dimensional convolution filter
gl:copyConvolutionFilter2D defines a two-dimensional convolution filter kernel with
pixels from the current ?GL_READ_BUFFER (rather than from main memory, as is the
case for gl:convolutionFilter2D/7 ).
The screen-aligned pixel rectangle with lower-left corner at ( X , Y ), width Width
and height Height is used to define the convolution filter. If any pixels within
this region are outside the window that is associated with the GL context, the
values obtained for those pixels are undefined.
The pixels in the rectangle are processed exactly as if gl:readPixels/7 had been
called with format set to RGBA, but the process stops just before final conversion.
The R, G, B, and A components of each pixel are next scaled by the four 2D
?GL_CONVOLUTION_FILTER_SCALE parameters and biased by the four 2D
?GL_CONVOLUTION_FILTER_BIAS parameters. (The scale and bias parameters are set by
gl:convolutionParameterf/3 using the ?GL_CONVOLUTION_2D target and the names
?GL_CONVOLUTION_FILTER_SCALE and ?GL_CONVOLUTION_FILTER_BIAS . The parameters
themselves are vectors of four values that are applied to red, green, blue, and
alpha, in that order.) The R, G, B, and A values are not clamped to [0,1] at any
time during this process.
Each pixel is then converted to the internal format specified by Internalformat .
This conversion simply maps the component values of the pixel (R, G, B, and A) to
the values included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_ALPHA A
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
The red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in floating-point rather than integer format.
Pixel ordering is such that lower x screen coordinates correspond to lower i filter
image coordinates, and lower y screen coordinates correspond to lower j filter
image coordinates.
Note that after a convolution is performed, the resulting color components are also
scaled by their corresponding ?GL_POST_CONVOLUTION_c_SCALE parameters and biased by
their corresponding ?GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the
values RED, GREEN, BLUE, and ALPHA). These parameters are set by
gl:pixelTransferf/2 .
See external documentation.
getConvolutionFilter(Target, Format, Type, Image) -> ok
Types:
Target = enum()
Format = enum()
Type = enum()
Image = mem()
Get current 1D or 2D convolution filter kernel
gl:getConvolutionFilter returns the current 1D or 2D convolution filter kernel as
an image. The one- or two-dimensional image is placed in Image according to the
specifications in Format and Type . No pixel transfer operations are performed on
this image, but the relevant pixel storage modes are applied.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a convolution filter is requested, Image is treated as a
byte offset into the buffer object's data store.
Color components that are present in Format but not included in the internal format
of the filter are returned as zero. The assignments of internal color components to
the components of Format are as follows.Internal ComponentResulting Component
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
Intensity Red
See external documentation.
getConvolutionParameterfv(Target, Pname) -> {float(), float(), float(), float()}
Types:
Target = enum()
Pname = enum()
Get convolution parameters
gl:getConvolutionParameter retrieves convolution parameters. Target determines
which convolution filter is queried. Pname determines which parameter is returned:
?GL_CONVOLUTION_BORDER_MODE: The convolution border mode. See
gl:convolutionParameterf/3 for a list of border modes.
?GL_CONVOLUTION_BORDER_COLOR: The current convolution border color. Params must be
a pointer to an array of four elements, which will receive the red, green, blue,
and alpha border colors.
?GL_CONVOLUTION_FILTER_SCALE: The current filter scale factors. Params must be a
pointer to an array of four elements, which will receive the red, green, blue, and
alpha filter scale factors in that order.
?GL_CONVOLUTION_FILTER_BIAS: The current filter bias factors. Params must be a
pointer to an array of four elements, which will receive the red, green, blue, and
alpha filter bias terms in that order.
?GL_CONVOLUTION_FORMAT: The current internal format. See gl:convolutionFilter1D/6 ,
gl:convolutionFilter2D/7 , and gl:separableFilter2D/8 for lists of allowable
formats.
?GL_CONVOLUTION_WIDTH: The current filter image width.
?GL_CONVOLUTION_HEIGHT: The current filter image height.
?GL_MAX_CONVOLUTION_WIDTH: The maximum acceptable filter image width.
?GL_MAX_CONVOLUTION_HEIGHT: The maximum acceptable filter image height.
See external documentation.
getConvolutionParameteriv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
See getConvolutionParameterfv/2
separableFilter2D(Target, Internalformat, Width, Height, Format, Type, Row, Column) -> ok
Types:
Target = enum()
Internalformat = enum()
Width = integer()
Height = integer()
Format = enum()
Type = enum()
Row = offset() | mem()
Column = offset() | mem()
Define a separable two-dimensional convolution filter
gl:separableFilter2D builds a two-dimensional separable convolution filter kernel
from two arrays of pixels.
The pixel arrays specified by ( Width , Format , Type , Row ) and ( Height , Format
, Type , Column ) are processed just as if they had been passed to gl:drawPixels/5
, but processing stops after the final expansion to RGBA is completed.
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a convolution filter is specified, Row and Column are
treated as byte offsets into the buffer object's data store.
Next, the R, G, B, and A components of all pixels in both arrays are scaled by the
four separable 2D ?GL_CONVOLUTION_FILTER_SCALE parameters and biased by the four
separable 2D ?GL_CONVOLUTION_FILTER_BIAS parameters. (The scale and bias parameters
are set by gl:convolutionParameterf/3 using the ?GL_SEPARABLE_2D target and the
names ?GL_CONVOLUTION_FILTER_SCALE and ?GL_CONVOLUTION_FILTER_BIAS. The parameters
themselves are vectors of four values that are applied to red, green, blue, and
alpha, in that order.) The R, G, B, and A values are not clamped to [0,1] at any
time during this process.
Each pixel is then converted to the internal format specified by Internalformat .
This conversion simply maps the component values of the pixel (R, G, B, and A) to
the values included in the internal format (red, green, blue, alpha, luminance, and
intensity). The mapping is as follows:Internal
FormatRedGreenBlueAlphaLuminanceIntensity
?GL_LUMINANCE R
?GL_LUMINANCE_ALPHA A R
?GL_INTENSITY R
?GL_RGB R G B
?GL_RGBA R G B A
The red, green, blue, alpha, luminance, and/or intensity components of the
resulting pixels are stored in floating-point rather than integer format. They form
two one-dimensional filter kernel images. The row image is indexed by coordinate i
starting at zero and increasing from left to right. Each location in the row image
is derived from element i of Row . The column image is indexed by coordinate j
starting at zero and increasing from bottom to top. Each location in the column
image is derived from element j of Column .
Note that after a convolution is performed, the resulting color components are also
scaled by their corresponding ?GL_POST_CONVOLUTION_c_SCALE parameters and biased by
their corresponding ?GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the
values RED, GREEN, BLUE, and ALPHA). These parameters are set by
gl:pixelTransferf/2 .
See external documentation.
getHistogram(Target, Reset, Format, Type, Values) -> ok
Types:
Target = enum()
Reset = 0 | 1
Format = enum()
Type = enum()
Values = mem()
Get histogram table
gl:getHistogram returns the current histogram table as a one-dimensional image with
the same width as the histogram. No pixel transfer operations are performed on this
image, but pixel storage modes that are applicable to 1D images are honored.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a histogram table is requested, Values is treated as a byte
offset into the buffer object's data store.
Color components that are requested in the specified Format , but which are not
included in the internal format of the histogram, are returned as zero. The
assignments of internal color components to the components requested by Format
are:Internal ComponentResulting Component
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
See external documentation.
getHistogramParameterfv(Target, Pname) -> {float()}
Types:
Target = enum()
Pname = enum()
Get histogram parameters
gl:getHistogramParameter is used to query parameter values for the current
histogram or for a proxy. The histogram state information may be queried by calling
gl:getHistogramParameter with a Target of ?GL_HISTOGRAM (to obtain information for
the current histogram table) or ?GL_PROXY_HISTOGRAM (to obtain information from the
most recent proxy request) and one of the following values for the Pname
argument:ParameterDescription
?GL_HISTOGRAM_WIDTH Histogram table width
?GL_HISTOGRAM_FORMAT Internal format
?GL_HISTOGRAM_RED_SIZE Red component counter size, in bits
?GL_HISTOGRAM_GREEN_SIZE Green component counter size, in bits
?GL_HISTOGRAM_BLUE_SIZE Blue component counter size, in bits
?GL_HISTOGRAM_ALPHA_SIZE Alpha component counter size, in bits
?GL_HISTOGRAM_LUMINANCE_SIZE Luminance component counter size, in bits
?GL_HISTOGRAM_SINK Value of the sink parameter
See external documentation.
getHistogramParameteriv(Target, Pname) -> {integer()}
Types:
Target = enum()
Pname = enum()
See getHistogramParameterfv/2
getMinmax(Target, Reset, Format, Types, Values) -> ok
Types:
Target = enum()
Reset = 0 | 1
Format = enum()
Types = enum()
Values = mem()
Get minimum and maximum pixel values
gl:getMinmax returns the accumulated minimum and maximum pixel values (computed on
a per-component basis) in a one-dimensional image of width 2. The first set of
return values are the minima, and the second set of return values are the maxima.
The format of the return values is determined by Format , and their type is
determined by Types .
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while minimum and maximum pixel values are requested, Values is
treated as a byte offset into the buffer object's data store.
No pixel transfer operations are performed on the return values, but pixel storage
modes that are applicable to one-dimensional images are performed. Color components
that are requested in the specified Format , but that are not included in the
internal format of the minmax table, are returned as zero. The assignment of
internal color components to the components requested by Format are as
follows:Internal ComponentResulting Component
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
If Reset is ?GL_TRUE, the minmax table entries corresponding to the return values
are reset to their initial values. Minimum and maximum values that are not returned
are not modified, even if Reset is ?GL_TRUE.
See external documentation.
getMinmaxParameterfv(Target, Pname) -> {float()}
Types:
Target = enum()
Pname = enum()
Get minmax parameters
gl:getMinmaxParameter retrieves parameters for the current minmax table by setting
Pname to one of the following values:ParameterDescription
?GL_MINMAX_FORMAT Internal format of minmax table
?GL_MINMAX_SINK Value of the sink parameter
See external documentation.
getMinmaxParameteriv(Target, Pname) -> {integer()}
Types:
Target = enum()
Pname = enum()
See getMinmaxParameterfv/2
histogram(Target, Width, Internalformat, Sink) -> ok
Types:
Target = enum()
Width = integer()
Internalformat = enum()
Sink = 0 | 1
Define histogram table
When ?GL_HISTOGRAM is enabled, RGBA color components are converted to histogram
table indices by clamping to the range [0,1], multiplying by the width of the
histogram table, and rounding to the nearest integer. The table entries selected by
the RGBA indices are then incremented. (If the internal format of the histogram
table includes luminance, then the index derived from the R color component
determines the luminance table entry to be incremented.) If a histogram table entry
is incremented beyond its maximum value, then its value becomes undefined. (This is
not an error.)
Histogramming is performed only for RGBA pixels (though these may be specified
originally as color indices and converted to RGBA by index table lookup).
Histogramming is enabled with gl:enable/1 and disabled with gl:enable/1 .
When Target is ?GL_HISTOGRAM, gl:histogram redefines the current histogram table to
have Width entries of the format specified by Internalformat . The entries are
indexed 0 through width-1, and all entries are initialized to zero. The values in
the previous histogram table, if any, are lost. If Sink is ?GL_TRUE , then pixels
are discarded after histogramming; no further processing of the pixels takes place,
and no drawing, texture loading, or pixel readback will result.
When Target is ?GL_PROXY_HISTOGRAM, gl:histogram computes all state information as
if the histogram table were to be redefined, but does not actually define the new
table. If the requested histogram table is too large to be supported, then the
state information will be set to zero. This provides a way to determine if a
histogram table with the given parameters can be supported.
See external documentation.
minmax(Target, Internalformat, Sink) -> ok
Types:
Target = enum()
Internalformat = enum()
Sink = 0 | 1
Define minmax table
When ?GL_MINMAX is enabled, the RGBA components of incoming pixels are compared to
the minimum and maximum values for each component, which are stored in the two-
element minmax table. (The first element stores the minima, and the second element
stores the maxima.) If a pixel component is greater than the corresponding
component in the maximum element, then the maximum element is updated with the
pixel component value. If a pixel component is less than the corresponding
component in the minimum element, then the minimum element is updated with the
pixel component value. (In both cases, if the internal format of the minmax table
includes luminance, then the R color component of incoming pixels is used for
comparison.) The contents of the minmax table may be retrieved at a later time by
calling gl:getMinmax/5 . The minmax operation is enabled or disabled by calling
gl:enable/1 or gl:enable/1 , respectively, with an argument of ?GL_MINMAX .
gl:minmax redefines the current minmax table to have entries of the format
specified by Internalformat . The maximum element is initialized with the smallest
possible component values, and the minimum element is initialized with the largest
possible component values. The values in the previous minmax table, if any, are
lost. If Sink is ?GL_TRUE , then pixels are discarded after minmax; no further
processing of the pixels takes place, and no drawing, texture loading, or pixel
readback will result.
See external documentation.
resetHistogram(Target) -> ok
Types:
Target = enum()
Reset histogram table entries to zero
gl:resetHistogram resets all the elements of the current histogram table to zero.
See external documentation.
resetMinmax(Target) -> ok
Types:
Target = enum()
Reset minmax table entries to initial values
gl:resetMinmax resets the elements of the current minmax table to their initial
values: the maximum element receives the minimum possible component values, and the
minimum element receives the maximum possible component values.
See external documentation.
activeTexture(Texture) -> ok
Types:
Texture = enum()
Select active texture unit
gl:activeTexture selects which texture unit subsequent texture state calls will
affect. The number of texture units an implementation supports is implementation
dependent, but must be at least 80.
See external documentation.
sampleCoverage(Value, Invert) -> ok
Types:
Value = clamp()
Invert = 0 | 1
Specify multisample coverage parameters
Multisampling samples a pixel multiple times at various implementation-dependent
subpixel locations to generate antialiasing effects. Multisampling transparently
antialiases points, lines, polygons, and images if it is enabled.
Value is used in constructing a temporary mask used in determining which samples
will be used in resolving the final fragment color. This mask is bitwise-anded with
the coverage mask generated from the multisampling computation. If the Invert flag
is set, the temporary mask is inverted (all bits flipped) and then the bitwise-and
is computed.
If an implementation does not have any multisample buffers available, or
multisampling is disabled, rasterization occurs with only a single sample computing
a pixel's final RGB color.
Provided an implementation supports multisample buffers, and multisampling is
enabled, then a pixel's final color is generated by combining several samples per
pixel. Each sample contains color, depth, and stencil information, allowing those
operations to be performed on each sample.
See external documentation.
compressedTexImage3D(Target, Level, Internalformat, Width, Height, Depth, Border,
ImageSize, Data) -> ok
Types:
Target = enum()
Level = integer()
Internalformat = enum()
Width = integer()
Height = integer()
Depth = integer()
Border = integer()
ImageSize = integer()
Data = offset() | mem()
Specify a three-dimensional texture image in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexImage3D loads a previously defined, and retrieved, compressed
three-dimensional texture image if Target is ?GL_TEXTURE_3D (see gl:texImage3D/10
).
If Target is ?GL_TEXTURE_2D_ARRAY, Data is treated as an array of compressed 2D
textures.
If Target is ?GL_PROXY_TEXTURE_3D or ?GL_PROXY_TEXTURE_2D_ARRAY, no data is read
from Data , but all of the texture image state is recalculated, checked for
consistency, and checked against the implementation's capabilities. If the
implementation cannot handle a texture of the requested texture size, it sets all
of the image state to 0, but does not generate an error (see gl:getError/0 ). To
query for an entire mipmap array, use an image array level greater than or equal to
1.
Internalformat must be a known compressed image format (such as ?GL_RGTC) or an
extension-specified compressed-texture format. When a texture is loaded with
gl:texImage2D/9 using a generic compressed texture format (e.g.,
?GL_COMPRESSED_RGB), the GL selects from one of its extensions supporting
compressed textures. In order to load the compressed texture image using
gl:compressedTexImage3D, query the compressed texture image's size and format using
gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
If the compressed data are arranged into fixed-size blocks of texels, the pixel
storage modes can be used to select a sub-rectangle from a larger containing
rectangle. These pixel storage modes operate in the same way as they do for
gl:texImage1D/8 . In the following description, denote by b s, b w, b h, and b d,
the values of pixel storage modes ?GL_UNPACK_COMPRESSED_BLOCK_SIZE,
?GL_UNPACK_COMPRESSED_BLOCK_WIDTH, ?GL_UNPACK_COMPRESSED_BLOCK_HEIGHT , and
?GL_UNPACK_COMPRESSED_BLOCK_DEPTH, respectively. b s is the compressed block size
in bytes; b w, b h, and b d are the compressed block width, height, and depth in
pixels.
By default the pixel storage modes ?GL_UNPACK_ROW_LENGTH, ?GL_UNPACK_SKIP_ROWS ,
?GL_UNPACK_SKIP_PIXELS, ?GL_UNPACK_IMAGE_HEIGHT and ?GL_UNPACK_SKIP_IMAGES are
ignored for compressed images. To enable ?GL_UNPACK_SKIP_PIXELS and
?GL_UNPACK_ROW_LENGTH , b s and b w must both be non-zero. To also enable
?GL_UNPACK_SKIP_ROWS and ?GL_UNPACK_IMAGE_HEIGHT , b h must be non-zero. To also
enable ?GL_UNPACK_SKIP_IMAGES, b d must be non-zero. All parameters must be
consistent with the compressed format to produce the desired results.
When selecting a sub-rectangle from a compressed image: the value of
?GL_UNPACK_SKIP_PIXELS must be a multiple of b w;the value of ?GL_UNPACK_SKIP_ROWS
must be a multiple of b w;the value of ?GL_UNPACK_SKIP_IMAGES must be a multiple of
b w.
ImageSize must be equal to:
b s×|width b/w|×|height b/h|×|depth b/d|
See external documentation.
compressedTexImage2D(Target, Level, Internalformat, Width, Height, Border, ImageSize,
Data) -> ok
Types:
Target = enum()
Level = integer()
Internalformat = enum()
Width = integer()
Height = integer()
Border = integer()
ImageSize = integer()
Data = offset() | mem()
Specify a two-dimensional texture image in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexImage2D loads a previously defined, and retrieved, compressed two-
dimensional texture image if Target is ?GL_TEXTURE_2D, or one of the cube map faces
such as ?GL_TEXTURE_CUBE_MAP_POSITIVE_X. (see gl:texImage2D/9 ).
If Target is ?GL_TEXTURE_1D_ARRAY, Data is treated as an array of compressed 1D
textures.
If Target is ?GL_PROXY_TEXTURE_2D, ?GL_PROXY_TEXTURE_1D_ARRAY or ?GL_PROXY_CUBE_MAP
, no data is read from Data , but all of the texture image state is recalculated,
checked for consistency, and checked against the implementation's capabilities. If
the implementation cannot handle a texture of the requested texture size, it sets
all of the image state to 0, but does not generate an error (see gl:getError/0 ).
To query for an entire mipmap array, use an image array level greater than or equal
to 1.
Internalformat must be a known compressed image format (such as ?GL_RGTC) or an
extension-specified compressed-texture format. When a texture is loaded with
gl:texImage2D/9 using a generic compressed texture format (e.g.,
?GL_COMPRESSED_RGB), the GL selects from one of its extensions supporting
compressed textures. In order to load the compressed texture image using
gl:compressedTexImage2D, query the compressed texture image's size and format using
gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
If the compressed data are arranged into fixed-size blocks of texels, the pixel
storage modes can be used to select a sub-rectangle from a larger containing
rectangle. These pixel storage modes operate in the same way as they do for
gl:texImage2D/9 . In the following description, denote by b s, b w, b h, and b d,
the values of pixel storage modes ?GL_UNPACK_COMPRESSED_BLOCK_SIZE,
?GL_UNPACK_COMPRESSED_BLOCK_WIDTH, ?GL_UNPACK_COMPRESSED_BLOCK_HEIGHT , and
?GL_UNPACK_COMPRESSED_BLOCK_DEPTH, respectively. b s is the compressed block size
in bytes; b w, b h, and b d are the compressed block width, height, and depth in
pixels.
By default the pixel storage modes ?GL_UNPACK_ROW_LENGTH, ?GL_UNPACK_SKIP_ROWS ,
?GL_UNPACK_SKIP_PIXELS, ?GL_UNPACK_IMAGE_HEIGHT and ?GL_UNPACK_SKIP_IMAGES are
ignored for compressed images. To enable ?GL_UNPACK_SKIP_PIXELS and
?GL_UNPACK_ROW_LENGTH , b s and b w must both be non-zero. To also enable
?GL_UNPACK_SKIP_ROWS and ?GL_UNPACK_IMAGE_HEIGHT , b h must be non-zero. To also
enable ?GL_UNPACK_SKIP_IMAGES, b d must be non-zero. All parameters must be
consistent with the compressed format to produce the desired results.
When selecting a sub-rectangle from a compressed image: the value of
?GL_UNPACK_SKIP_PIXELS must be a multiple of b w;the value of ?GL_UNPACK_SKIP_ROWS
must be a multiple of b w.
ImageSize must be equal to:
b s×|width b/w|×|height b/h|
See external documentation.
compressedTexImage1D(Target, Level, Internalformat, Width, Border, ImageSize, Data) -> ok
Types:
Target = enum()
Level = integer()
Internalformat = enum()
Width = integer()
Border = integer()
ImageSize = integer()
Data = offset() | mem()
Specify a one-dimensional texture image in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexImage1D loads a previously defined, and retrieved, compressed one-
dimensional texture image if Target is ?GL_TEXTURE_1D (see gl:texImage1D/8 ).
If Target is ?GL_PROXY_TEXTURE_1D, no data is read from Data , but all of the
texture image state is recalculated, checked for consistency, and checked against
the implementation's capabilities. If the implementation cannot handle a texture of
the requested texture size, it sets all of the image state to 0, but does not
generate an error (see gl:getError/0 ). To query for an entire mipmap array, use an
image array level greater than or equal to 1.
Internalformat must be an extension-specified compressed-texture format. When a
texture is loaded with gl:texImage1D/8 using a generic compressed texture format
(e.g., ?GL_COMPRESSED_RGB) the GL selects from one of its extensions supporting
compressed textures. In order to load the compressed texture image using
gl:compressedTexImage1D , query the compressed texture image's size and format
using gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
If the compressed data are arranged into fixed-size blocks of texels, the pixel
storage modes can be used to select a sub-rectangle from a larger containing
rectangle. These pixel storage modes operate in the same way as they do for
gl:texImage1D/8 . In the following description, denote by b s, b w, b h, and b d,
the values of pixel storage modes ?GL_UNPACK_COMPRESSED_BLOCK_SIZE,
?GL_UNPACK_COMPRESSED_BLOCK_WIDTH, ?GL_UNPACK_COMPRESSED_BLOCK_HEIGHT , and
?GL_UNPACK_COMPRESSED_BLOCK_DEPTH, respectively. b s is the compressed block size
in bytes; b w, b h, and b d are the compressed block width, height, and depth in
pixels.
By default the pixel storage modes ?GL_UNPACK_ROW_LENGTH, ?GL_UNPACK_SKIP_ROWS ,
?GL_UNPACK_SKIP_PIXELS, ?GL_UNPACK_IMAGE_HEIGHT and ?GL_UNPACK_SKIP_IMAGES are
ignored for compressed images. To enable ?GL_UNPACK_SKIP_PIXELS and
?GL_UNPACK_ROW_LENGTH , b s and b w must both be non-zero. To also enable
?GL_UNPACK_SKIP_ROWS and ?GL_UNPACK_IMAGE_HEIGHT , b h must be non-zero. To also
enable ?GL_UNPACK_SKIP_IMAGES, b d must be non-zero. All parameters must be
consistent with the compressed format to produce the desired results.
When selecting a sub-rectangle from a compressed image: the value of
?GL_UNPACK_SKIP_PIXELS must be a multiple of b w;
ImageSize must be equal to:
b s×|width b/w|
See external documentation.
compressedTexSubImage3D(Target, Level, Xoffset, Yoffset, Zoffset, Width, Height, Depth,
Format, ImageSize, Data) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
Zoffset = integer()
Width = integer()
Height = integer()
Depth = integer()
Format = enum()
ImageSize = integer()
Data = offset() | mem()
Specify a three-dimensional texture subimage in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexSubImage3D redefines a contiguous subregion of an existing three-
dimensional texture image. The texels referenced by Data replace the portion of the
existing texture array with x indices Xoffset and xoffset+width-1, and the y
indices Yoffset and yoffset+height-1, and the z indices Zoffset and
zoffset+depth-1, inclusive. This region may not include any texels outside the
range of the texture array as it was originally specified. It is not an error to
specify a subtexture with width of 0, but such a specification has no effect.
Internalformat must be a known compressed image format (such as ?GL_RGTC) or an
extension-specified compressed-texture format. The Format of the compressed texture
image is selected by the GL implementation that compressed it (see gl:texImage3D/10
) and should be queried at the time the texture was compressed with
gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
See external documentation.
compressedTexSubImage2D(Target, Level, Xoffset, Yoffset, Width, Height, Format, ImageSize,
Data) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Yoffset = integer()
Width = integer()
Height = integer()
Format = enum()
ImageSize = integer()
Data = offset() | mem()
Specify a two-dimensional texture subimage in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexSubImage2D redefines a contiguous subregion of an existing two-
dimensional texture image. The texels referenced by Data replace the portion of the
existing texture array with x indices Xoffset and xoffset+width-1, and the y
indices Yoffset and yoffset+height-1, inclusive. This region may not include any
texels outside the range of the texture array as it was originally specified. It is
not an error to specify a subtexture with width of 0, but such a specification has
no effect.
Internalformat must be a known compressed image format (such as ?GL_RGTC) or an
extension-specified compressed-texture format. The Format of the compressed texture
image is selected by the GL implementation that compressed it (see gl:texImage2D/9
) and should be queried at the time the texture was compressed with
gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
See external documentation.
compressedTexSubImage1D(Target, Level, Xoffset, Width, Format, ImageSize, Data) -> ok
Types:
Target = enum()
Level = integer()
Xoffset = integer()
Width = integer()
Format = enum()
ImageSize = integer()
Data = offset() | mem()
Specify a one-dimensional texture subimage in a compressed format
Texturing allows elements of an image array to be read by shaders.
gl:compressedTexSubImage1D redefines a contiguous subregion of an existing one-
dimensional texture image. The texels referenced by Data replace the portion of the
existing texture array with x indices Xoffset and xoffset+width-1, inclusive. This
region may not include any texels outside the range of the texture array as it was
originally specified. It is not an error to specify a subtexture with width of 0,
but such a specification has no effect.
Internalformat must be a known compressed image format (such as ?GL_RGTC) or an
extension-specified compressed-texture format. The Format of the compressed texture
image is selected by the GL implementation that compressed it (see gl:texImage1D/8
), and should be queried at the time the texture was compressed with
gl:getTexLevelParameterfv/3 .
If a non-zero named buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target
(see gl:bindBuffer/2 ) while a texture image is specified, Data is treated as a
byte offset into the buffer object's data store.
See external documentation.
getCompressedTexImage(Target, Lod, Img) -> ok
Types:
Target = enum()
Lod = integer()
Img = mem()
Return a compressed texture image
gl:getCompressedTexImage returns the compressed texture image associated with
Target and Lod into Img . Img should be an array of
?GL_TEXTURE_COMPRESSED_IMAGE_SIZE bytes. Target specifies whether the desired
texture image was one specified by gl:texImage1D/8 (?GL_TEXTURE_1D),
gl:texImage2D/9 (?GL_TEXTURE_2D or any of ?GL_TEXTURE_CUBE_MAP_* ), or
gl:texImage3D/10 (?GL_TEXTURE_3D). Lod specifies the level-of-detail number of the
desired image.
If a non-zero named buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target (see
gl:bindBuffer/2 ) while a texture image is requested, Img is treated as a byte
offset into the buffer object's data store.
To minimize errors, first verify that the texture is compressed by calling
gl:getTexLevelParameterfv/3 with argument ?GL_TEXTURE_COMPRESSED. If the texture is
compressed, then determine the amount of memory required to store the compressed
texture by calling gl:getTexLevelParameterfv/3 with argument
?GL_TEXTURE_COMPRESSED_IMAGE_SIZE. Finally, retrieve the internal format of the
texture by calling gl:getTexLevelParameterfv/3 with argument
?GL_TEXTURE_INTERNAL_FORMAT . To store the texture for later use, associate the
internal format and size with the retrieved texture image. These data can be used
by the respective texture or subtexture loading routine used for loading Target
textures.
See external documentation.
clientActiveTexture(Texture) -> ok
Types:
Texture = enum()
Select active texture unit
gl:clientActiveTexture selects the vertex array client state parameters to be
modified by gl:texCoordPointer/4 , and enabled or disabled with
gl:enableClientState/1 or gl:enableClientState/1 , respectively, when called with a
parameter of ?GL_TEXTURE_COORD_ARRAY .
See external documentation.
multiTexCoord1d(Target, S) -> ok
Types:
Target = enum()
S = float()
Set the current texture coordinates
gl:multiTexCoord specifies texture coordinates in one, two, three, or four
dimensions. gl:multiTexCoord1 sets the current texture coordinates to (s 0 0 1); a
call to gl:multiTexCoord2 sets them to (s t 0 1). Similarly, gl:multiTexCoord3
specifies the texture coordinates as (s t r 1), and gl:multiTexCoord4 defines all
four components explicitly as (s t r q).
The current texture coordinates are part of the data that is associated with each
vertex and with the current raster position. Initially, the values for (s t r q)
are (0 0 0 1).
See external documentation.
multiTexCoord1dv(Target::enum(), V) -> ok
Types:
V = {S::float()}
Equivalent to multiTexCoord1d(Target, S).
multiTexCoord1f(Target, S) -> ok
Types:
Target = enum()
S = float()
See multiTexCoord1d/2
multiTexCoord1fv(Target::enum(), V) -> ok
Types:
V = {S::float()}
Equivalent to multiTexCoord1f(Target, S).
multiTexCoord1i(Target, S) -> ok
Types:
Target = enum()
S = integer()
See multiTexCoord1d/2
multiTexCoord1iv(Target::enum(), V) -> ok
Types:
V = {S::integer()}
Equivalent to multiTexCoord1i(Target, S).
multiTexCoord1s(Target, S) -> ok
Types:
Target = enum()
S = integer()
See multiTexCoord1d/2
multiTexCoord1sv(Target::enum(), V) -> ok
Types:
V = {S::integer()}
Equivalent to multiTexCoord1s(Target, S).
multiTexCoord2d(Target, S, T) -> ok
Types:
Target = enum()
S = float()
T = float()
See multiTexCoord1d/2
multiTexCoord2dv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float()}
Equivalent to multiTexCoord2d(Target, S, T).
multiTexCoord2f(Target, S, T) -> ok
Types:
Target = enum()
S = float()
T = float()
See multiTexCoord1d/2
multiTexCoord2fv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float()}
Equivalent to multiTexCoord2f(Target, S, T).
multiTexCoord2i(Target, S, T) -> ok
Types:
Target = enum()
S = integer()
T = integer()
See multiTexCoord1d/2
multiTexCoord2iv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer()}
Equivalent to multiTexCoord2i(Target, S, T).
multiTexCoord2s(Target, S, T) -> ok
Types:
Target = enum()
S = integer()
T = integer()
See multiTexCoord1d/2
multiTexCoord2sv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer()}
Equivalent to multiTexCoord2s(Target, S, T).
multiTexCoord3d(Target, S, T, R) -> ok
Types:
Target = enum()
S = float()
T = float()
R = float()
See multiTexCoord1d/2
multiTexCoord3dv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float(), R::float()}
Equivalent to multiTexCoord3d(Target, S, T, R).
multiTexCoord3f(Target, S, T, R) -> ok
Types:
Target = enum()
S = float()
T = float()
R = float()
See multiTexCoord1d/2
multiTexCoord3fv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float(), R::float()}
Equivalent to multiTexCoord3f(Target, S, T, R).
multiTexCoord3i(Target, S, T, R) -> ok
Types:
Target = enum()
S = integer()
T = integer()
R = integer()
See multiTexCoord1d/2
multiTexCoord3iv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer()}
Equivalent to multiTexCoord3i(Target, S, T, R).
multiTexCoord3s(Target, S, T, R) -> ok
Types:
Target = enum()
S = integer()
T = integer()
R = integer()
See multiTexCoord1d/2
multiTexCoord3sv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer()}
Equivalent to multiTexCoord3s(Target, S, T, R).
multiTexCoord4d(Target, S, T, R, Q) -> ok
Types:
Target = enum()
S = float()
T = float()
R = float()
Q = float()
See multiTexCoord1d/2
multiTexCoord4dv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float(), R::float(), Q::float()}
Equivalent to multiTexCoord4d(Target, S, T, R, Q).
multiTexCoord4f(Target, S, T, R, Q) -> ok
Types:
Target = enum()
S = float()
T = float()
R = float()
Q = float()
See multiTexCoord1d/2
multiTexCoord4fv(Target::enum(), V) -> ok
Types:
V = {S::float(), T::float(), R::float(), Q::float()}
Equivalent to multiTexCoord4f(Target, S, T, R, Q).
multiTexCoord4i(Target, S, T, R, Q) -> ok
Types:
Target = enum()
S = integer()
T = integer()
R = integer()
Q = integer()
See multiTexCoord1d/2
multiTexCoord4iv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer(), Q::integer()}
Equivalent to multiTexCoord4i(Target, S, T, R, Q).
multiTexCoord4s(Target, S, T, R, Q) -> ok
Types:
Target = enum()
S = integer()
T = integer()
R = integer()
Q = integer()
See multiTexCoord1d/2
multiTexCoord4sv(Target::enum(), V) -> ok
Types:
V = {S::integer(), T::integer(), R::integer(), Q::integer()}
Equivalent to multiTexCoord4s(Target, S, T, R, Q).
loadTransposeMatrixf(M) -> ok
Types:
M = matrix()
Replace the current matrix with the specified row-major ordered matrix
gl:loadTransposeMatrix replaces the current matrix with the one whose elements are
specified by M . The current matrix is the projection matrix, modelview matrix, or
texture matrix, depending on the current matrix mode (see gl:matrixMode/1 ).
The current matrix, M, defines a transformation of coordinates. For instance,
assume M refers to the modelview matrix. If v=(v[0] v[1] v[2] v[3]) is the set of
object coordinates of a vertex, and M points to an array of 16 single- or double-
precision floating-point values m={m[0] m[1] ... m[15]}, then the modelview
transformation M(v) does the following:
M(v)=(m[0] m[1] m[2] m[3] m[4] m[5] m[6] m[7] m[8] m[9] m[10] m[11] m[12] m[13]
m[14] m[15])×(v[0] v[1] v[2] v[3])
Projection and texture transformations are similarly defined.
Calling gl:loadTransposeMatrix with matrix M is identical in operation to
gl:loadMatrixd/1 with M T, where T represents the transpose.
See external documentation.
loadTransposeMatrixd(M) -> ok
Types:
M = matrix()
See loadTransposeMatrixf/1
multTransposeMatrixf(M) -> ok
Types:
M = matrix()
Multiply the current matrix with the specified row-major ordered matrix
gl:multTransposeMatrix multiplies the current matrix with the one specified using M
, and replaces the current matrix with the product.
The current matrix is determined by the current matrix mode (see gl:matrixMode/1 ).
It is either the projection matrix, modelview matrix, or the texture matrix.
See external documentation.
multTransposeMatrixd(M) -> ok
Types:
M = matrix()
See multTransposeMatrixf/1
blendFuncSeparate(SfactorRGB, DfactorRGB, SfactorAlpha, DfactorAlpha) -> ok
Types:
SfactorRGB = enum()
DfactorRGB = enum()
SfactorAlpha = enum()
DfactorAlpha = enum()
Specify pixel arithmetic for RGB and alpha components separately
Pixels can be drawn using a function that blends the incoming (source) RGBA values
with the RGBA values that are already in the frame buffer (the destination values).
Blending is initially disabled. Use gl:enable/1 and gl:enable/1 with argument
?GL_BLEND to enable and disable blending.
gl:blendFuncSeparate defines the operation of blending for all draw buffers when it
is enabled. gl:blendFuncSeparatei defines the operation of blending for a single
draw buffer specified by Buf when enabled for that draw buffer. SrcRGB specifies
which method is used to scale the source RGB-color components. DstRGB specifies
which method is used to scale the destination RGB-color components. Likewise,
SrcAlpha specifies which method is used to scale the source alpha color component,
and DstAlpha specifies which method is used to scale the destination alpha
component. The possible methods are described in the following table. Each method
defines four scale factors, one each for red, green, blue, and alpha.
In the table and in subsequent equations, first source, second source and
destination color components are referred to as (R s0 G s0 B s0 A s0), (R s1 G s1 B
s1 A s1), and (R d G d B d A d), respectively. The color specified by
gl:blendColor/4 is referred to as (R c G c B c A c). They are understood to have
integer values between 0 and (k R k G k B k A), where
k c=2(m c)-1
and (m R m G m B m A) is the number of red, green, blue, and alpha bitplanes.
Source and destination scale factors are referred to as (s R s G s B s A) and (d R
d G d B d A). All scale factors have range [0 1].ParameterRGB FactorAlpha Factor
?GL_ZERO(0 0 0) 0
?GL_ONE (1 1 1) 1
?GL_SRC_COLOR(R s0 k/R G s0 k/G B s0 k/B) A s0 k/A
?GL_ONE_MINUS_SRC_COLOR(1 1 1 1)-(R s0 k/R G s0 k/G B s0 k/B) 1-A s0 k/A
?GL_DST_COLOR(R d k/R G d k/G B d k/B) A d k/A
?GL_ONE_MINUS_DST_COLOR (1 1 1)-(R d k/R G d k/G B d k/B) 1-A d k/A
?GL_SRC_ALPHA(A s0 k/A A s0 k/A A s0 k/A) A s0 k/A
?GL_ONE_MINUS_SRC_ALPHA(1 1 1)-(A s0 k/A A s0 k/A A s0 k/A ) 1-A s0 k/A
?GL_DST_ALPHA(A d k/A A d k/A A d k/A) A d k/A
?GL_ONE_MINUS_DST_ALPHA (1 1 1)-(A d k/A A d k/A A d k/A) 1-A d k/A
?GL_CONSTANT_COLOR(R c G c B c) A c
?GL_ONE_MINUS_CONSTANT_COLOR(1 1 1)-(R c G c B c) 1-A c
?GL_CONSTANT_ALPHA(A c A c A c) A c
?GL_ONE_MINUS_CONSTANT_ALPHA (1 1 1)-(A c A c A c) 1-A c
?GL_SRC_ALPHA_SATURATE(i i i) 1
?GL_SRC1_COLOR(R s1 k/R G s1 k/G B s1 k/B) A s1 k/A
?GL_ONE_MINUS_SRC_COLOR (1 1 1 1)-(R s1 k/R G s1 k/G B s1 k/B) 1-A s1 k/A
?GL_SRC1_ALPHA(A s1 k/A A s1 k/A A s1 k/A) A s1 k/A
?GL_ONE_MINUS_SRC_ALPHA(1 1 1)-(A s1 k/A A s1 k/A A s1 k/A ) 1-A s1 k/A
In the table,
i=min(A s 1-(A d))
To determine the blended RGBA values of a pixel, the system uses the following
equations:
R d=min(k R R s s R+R d d R) G d=min(k G G s s G+G d d G) B d=min(k B B s s B+B d d
B) A d=min(k A A s s A+A d d A)
Despite the apparent precision of the above equations, blending arithmetic is not
exactly specified, because blending operates with imprecise integer color values.
However, a blend factor that should be equal to 1 is guaranteed not to modify its
multiplicand, and a blend factor equal to 0 reduces its multiplicand to 0. For
example, when SrcRGB is ?GL_SRC_ALPHA , DstRGB is ?GL_ONE_MINUS_SRC_ALPHA, and A s
is equal to k A, the equations reduce to simple replacement:
R d=R s G d=G s B d=B s A d=A s
See external documentation.
multiDrawArrays(Mode, First, Count) -> ok
Types:
Mode = enum()
First = [integer()]
Count = [integer()]
Render multiple sets of primitives from array data
gl:multiDrawArrays specifies multiple sets of geometric primitives with very few
subroutine calls. Instead of calling a GL procedure to pass each individual vertex,
normal, texture coordinate, edge flag, or color, you can prespecify separate arrays
of vertices, normals, and colors and use them to construct a sequence of primitives
with a single call to gl:multiDrawArrays.
gl:multiDrawArrays behaves identically to gl:drawArrays/3 except that Primcount
separate ranges of elements are specified instead.
When gl:multiDrawArrays is called, it uses Count sequential elements from each
enabled array to construct a sequence of geometric primitives, beginning with
element First . Mode specifies what kind of primitives are constructed, and how the
array elements construct those primitives.
Vertex attributes that are modified by gl:multiDrawArrays have an unspecified value
after gl:multiDrawArrays returns. Attributes that aren't modified remain well
defined.
See external documentation.
pointParameterf(Pname, Param) -> ok
Types:
Pname = enum()
Param = float()
Specify point parameters
The following values are accepted for Pname :
?GL_POINT_FADE_THRESHOLD_SIZE: Params is a single floating-point value that
specifies the threshold value to which point sizes are clamped if they exceed the
specified value. The default value is 1.0.
?GL_POINT_SPRITE_COORD_ORIGIN: Params is a single enum specifying the point sprite
texture coordinate origin, either ?GL_LOWER_LEFT or ?GL_UPPER_LEFT. The default
value is ?GL_UPPER_LEFT.
See external documentation.
pointParameterfv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {float()}
See pointParameterf/2
pointParameteri(Pname, Param) -> ok
Types:
Pname = enum()
Param = integer()
See pointParameterf/2
pointParameteriv(Pname, Params) -> ok
Types:
Pname = enum()
Params = {integer()}
See pointParameterf/2
fogCoordf(Coord) -> ok
Types:
Coord = float()
Set the current fog coordinates
gl:fogCoord specifies the fog coordinate that is associated with each vertex and
the current raster position. The value specified is interpolated and used in
computing the fog color (see gl:fogf/2 ).
See external documentation.
fogCoordfv(Coord) -> ok
Types:
Coord = {Coord::float()}
Equivalent to fogCoordf(Coord).
fogCoordd(Coord) -> ok
Types:
Coord = float()
See fogCoordf/1
fogCoorddv(Coord) -> ok
Types:
Coord = {Coord::float()}
Equivalent to fogCoordd(Coord).
fogCoordPointer(Type, Stride, Pointer) -> ok
Types:
Type = enum()
Stride = integer()
Pointer = offset() | mem()
Define an array of fog coordinates
gl:fogCoordPointer specifies the location and data format of an array of fog
coordinates to use when rendering. Type specifies the data type of each fog
coordinate, and Stride specifies the byte stride from one fog coordinate to the
next, allowing vertices and attributes to be packed into a single array or stored
in separate arrays.
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a fog coordinate array is specified, Pointer is treated as
a byte offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as fog coordinate vertex array client-side
state (?GL_FOG_COORD_ARRAY_BUFFER_BINDING ).
When a fog coordinate array is specified, Type , Stride , and Pointer are saved as
client-side state, in addition to the current vertex array buffer object binding.
To enable and disable the fog coordinate array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_FOG_COORD_ARRAY. If enabled, the fog
coordinate array is used when gl:drawArrays/3 , gl:multiDrawArrays/3 ,
gl:drawElements/4 , see glMultiDrawElements , gl:drawRangeElements/6 , or
gl:arrayElement/1 is called.
See external documentation.
secondaryColor3b(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
Set the current secondary color
The GL stores both a primary four-valued RGBA color and a secondary four-valued
RGBA color (where alpha is always set to 0.0) that is associated with every vertex.
The secondary color is interpolated and applied to each fragment during
rasterization when ?GL_COLOR_SUM is enabled. When lighting is enabled, and
?GL_SEPARATE_SPECULAR_COLOR is specified, the value of the secondary color is
assigned the value computed from the specular term of the lighting computation.
Both the primary and secondary current colors are applied to each fragment,
regardless of the state of ?GL_COLOR_SUM, under such conditions. When
?GL_SEPARATE_SPECULAR_COLOR is specified, the value returned from querying the
current secondary color is undefined.
gl:secondaryColor3b, gl:secondaryColor3s, and gl:secondaryColor3i take three signed
byte, short, or long integers as arguments. When v is appended to the name, the
color commands can take a pointer to an array of such values.
Color values are stored in floating-point format, with unspecified mantissa and
exponent sizes. Unsigned integer color components, when specified, are linearly
mapped to floating-point values such that the largest representable value maps to
1.0 (full intensity), and 0 maps to 0.0 (zero intensity). Signed integer color
components, when specified, are linearly mapped to floating-point values such that
the most positive representable value maps to 1.0, and the most negative
representable value maps to -1.0. (Note that this mapping does not convert 0
precisely to 0.0). Floating-point values are mapped directly.
Neither floating-point nor signed integer values are clamped to the range [0 1]
before the current color is updated. However, color components are clamped to this
range before they are interpolated or written into a color buffer.
See external documentation.
secondaryColor3bv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3b(Red, Green, Blue).
secondaryColor3d(Red, Green, Blue) -> ok
Types:
Red = float()
Green = float()
Blue = float()
See secondaryColor3b/3
secondaryColor3dv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float()}
Equivalent to secondaryColor3d(Red, Green, Blue).
secondaryColor3f(Red, Green, Blue) -> ok
Types:
Red = float()
Green = float()
Blue = float()
See secondaryColor3b/3
secondaryColor3fv(V) -> ok
Types:
V = {Red::float(), Green::float(), Blue::float()}
Equivalent to secondaryColor3f(Red, Green, Blue).
secondaryColor3i(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See secondaryColor3b/3
secondaryColor3iv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3i(Red, Green, Blue).
secondaryColor3s(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See secondaryColor3b/3
secondaryColor3sv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3s(Red, Green, Blue).
secondaryColor3ub(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See secondaryColor3b/3
secondaryColor3ubv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3ub(Red, Green, Blue).
secondaryColor3ui(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See secondaryColor3b/3
secondaryColor3uiv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3ui(Red, Green, Blue).
secondaryColor3us(Red, Green, Blue) -> ok
Types:
Red = integer()
Green = integer()
Blue = integer()
See secondaryColor3b/3
secondaryColor3usv(V) -> ok
Types:
V = {Red::integer(), Green::integer(), Blue::integer()}
Equivalent to secondaryColor3us(Red, Green, Blue).
secondaryColorPointer(Size, Type, Stride, Pointer) -> ok
Types:
Size = integer()
Type = enum()
Stride = integer()
Pointer = offset() | mem()
Define an array of secondary colors
gl:secondaryColorPointer specifies the location and data format of an array of
color components to use when rendering. Size specifies the number of components per
color, and must be 3. Type specifies the data type of each color component, and
Stride specifies the byte stride from one color to the next, allowing vertices and
attributes to be packed into a single array or stored in separate arrays.
If a non-zero named buffer object is bound to the ?GL_ARRAY_BUFFER target (see
gl:bindBuffer/2 ) while a secondary color array is specified, Pointer is treated as
a byte offset into the buffer object's data store. Also, the buffer object binding
(?GL_ARRAY_BUFFER_BINDING ) is saved as secondary color vertex array client-side
state (?GL_SECONDARY_COLOR_ARRAY_BUFFER_BINDING ).
When a secondary color array is specified, Size , Type , Stride , and Pointer are
saved as client-side state, in addition to the current vertex array buffer object
binding.
To enable and disable the secondary color array, call gl:enableClientState/1 and
gl:enableClientState/1 with the argument ?GL_SECONDARY_COLOR_ARRAY. If enabled, the
secondary color array is used when gl:arrayElement/1 , gl:drawArrays/3 ,
gl:multiDrawArrays/3 , gl:drawElements/4 , see glMultiDrawElements, or
gl:drawRangeElements/6 is called.
See external documentation.
windowPos2d(X, Y) -> ok
Types:
X = float()
Y = float()
Specify the raster position in window coordinates for pixel operations
The GL maintains a 3D position in window coordinates. This position, called the
raster position, is used to position pixel and bitmap write operations. It is
maintained with subpixel accuracy. See gl:bitmap/7 , gl:drawPixels/5 , and
gl:copyPixels/5 .
gl:windowPos2 specifies the x and y coordinates, while z is implicitly set to 0.
gl:windowPos3 specifies all three coordinates. The w coordinate of the current
raster position is always set to 1.0.
gl:windowPos directly updates the x and y coordinates of the current raster
position with the values specified. That is, the values are neither transformed by
the current modelview and projection matrices, nor by the viewport-to-window
transform. The z coordinate of the current raster position is updated in the
following manner:
z={n f(n+z×(f-n)) if z<= 0 if z>= 1(otherwise))
where n is ?GL_DEPTH_RANGE's near value, and f is ?GL_DEPTH_RANGE's far value. See
gl:depthRange/2 .
The specified coordinates are not clip-tested, causing the raster position to
always be valid.
The current raster position also includes some associated color data and texture
coordinates. If lighting is enabled, then ?GL_CURRENT_RASTER_COLOR (in RGBA mode)
or ?GL_CURRENT_RASTER_INDEX (in color index mode) is set to the color produced by
the lighting calculation (see gl:lightf/3 , gl:lightModelf/2 , and gl:shadeModel/1
). If lighting is disabled, current color (in RGBA mode, state variable
?GL_CURRENT_COLOR) or color index (in color index mode, state variable
?GL_CURRENT_INDEX) is used to update the current raster color.
?GL_CURRENT_RASTER_SECONDARY_COLOR (in RGBA mode) is likewise updated.
Likewise, ?GL_CURRENT_RASTER_TEXTURE_COORDS is updated as a function of
?GL_CURRENT_TEXTURE_COORDS , based on the texture matrix and the texture generation
functions (see gl:texGend/3 ). The ?GL_CURRENT_RASTER_DISTANCE is set to the
?GL_CURRENT_FOG_COORD.
See external documentation.
windowPos2dv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to windowPos2d(X, Y).
windowPos2f(X, Y) -> ok
Types:
X = float()
Y = float()
See windowPos2d/2
windowPos2fv(V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to windowPos2f(X, Y).
windowPos2i(X, Y) -> ok
Types:
X = integer()
Y = integer()
See windowPos2d/2
windowPos2iv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to windowPos2i(X, Y).
windowPos2s(X, Y) -> ok
Types:
X = integer()
Y = integer()
See windowPos2d/2
windowPos2sv(V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to windowPos2s(X, Y).
windowPos3d(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See windowPos2d/2
windowPos3dv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to windowPos3d(X, Y, Z).
windowPos3f(X, Y, Z) -> ok
Types:
X = float()
Y = float()
Z = float()
See windowPos2d/2
windowPos3fv(V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to windowPos3f(X, Y, Z).
windowPos3i(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See windowPos2d/2
windowPos3iv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to windowPos3i(X, Y, Z).
windowPos3s(X, Y, Z) -> ok
Types:
X = integer()
Y = integer()
Z = integer()
See windowPos2d/2
windowPos3sv(V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to windowPos3s(X, Y, Z).
genQueries(N) -> [integer()]
Types:
N = integer()
Generate query object names
gl:genQueries returns N query object names in Ids . There is no guarantee that the
names form a contiguous set of integers; however, it is guaranteed that none of the
returned names was in use immediately before the call to gl:genQueries.
Query object names returned by a call to gl:genQueries are not returned by
subsequent calls, unless they are first deleted with gl:deleteQueries/1 .
No query objects are associated with the returned query object names until they are
first used by calling gl:beginQuery/2 .
See external documentation.
deleteQueries(Ids) -> ok
Types:
Ids = [integer()]
Delete named query objects
gl:deleteQueries deletes N query objects named by the elements of the array Ids .
After a query object is deleted, it has no contents, and its name is free for reuse
(for example by gl:genQueries/1 ).
gl:deleteQueries silently ignores 0's and names that do not correspond to existing
query objects.
See external documentation.
isQuery(Id) -> 0 | 1
Types:
Id = integer()
Determine if a name corresponds to a query object
gl:isQuery returns ?GL_TRUE if Id is currently the name of a query object. If Id is
zero, or is a non-zero value that is not currently the name of a query object, or
if an error occurs, gl:isQuery returns ?GL_FALSE.
A name returned by gl:genQueries/1 , but not yet associated with a query object by
calling gl:beginQuery/2 , is not the name of a query object.
See external documentation.
beginQuery(Target, Id) -> ok
Types:
Target = enum()
Id = integer()
Delimit the boundaries of a query object
gl:beginQuery and gl:beginQuery/2 delimit the boundaries of a query object. Query
must be a name previously returned from a call to gl:genQueries/1 . If a query
object with name Id does not yet exist it is created with the type determined by
Target . Target must be one of ?GL_SAMPLES_PASSED, ?GL_ANY_SAMPLES_PASSED,
?GL_PRIMITIVES_GENERATED , ?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, or
?GL_TIME_ELAPSED. The behavior of the query object depends on its type and is as
follows.
If Target is ?GL_SAMPLES_PASSED, Id must be an unused name, or the name of an
existing occlusion query object. When gl:beginQuery is executed, the query object's
samples-passed counter is reset to 0. Subsequent rendering will increment the
counter for every sample that passes the depth test. If the value of
?GL_SAMPLE_BUFFERS is 0, then the samples-passed count is incremented by 1 for each
fragment. If the value of ?GL_SAMPLE_BUFFERS is 1, then the samples-passed count is
incremented by the number of samples whose coverage bit is set. However,
implementations, at their discression may instead increase the samples-passed count
by the value of ?GL_SAMPLES if any sample in the fragment is covered. When
gl:endQuery is executed, the samples-passed counter is assigned to the query
object's result value. This value can be queried by calling gl:getQueryObjectiv/2
with Pname ?GL_QUERY_RESULT.
If Target is ?GL_ANY_SAMPLES_PASSED, Id must be an unused name, or the name of an
existing boolean occlusion query object. When gl:beginQuery is executed, the query
object's samples-passed flag is reset to ?GL_FALSE. Subsequent rendering causes the
flag to be set to ?GL_TRUE if any sample passes the depth test. When gl:endQuery is
executed, the samples-passed flag is assigned to the query object's result value.
This value can be queried by calling gl:getQueryObjectiv/2 with Pname
?GL_QUERY_RESULT.
If Target is ?GL_PRIMITIVES_GENERATED, Id must be an unused name, or the name of an
existing primitive query object previously bound to the ?GL_PRIMITIVES_GENERATED
query binding. When gl:beginQuery is executed, the query object's primitives-
generated counter is reset to 0. Subsequent rendering will increment the counter
once for every vertex that is emitted from the geometry shader, or from the vertex
shader if no geometry shader is present. When gl:endQuery is executed, the
primitives-generated counter is assigned to the query object's result value. This
value can be queried by calling gl:getQueryObjectiv/2 with Pname ?GL_QUERY_RESULT.
If Target is ?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, Id must be an unused name,
or the name of an existing primitive query object previously bound to the
?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN query binding. When gl:beginQuery is
executed, the query object's primitives-written counter is reset to 0. Subsequent
rendering will increment the counter once for every vertex that is written into the
bound transform feedback buffer(s). If transform feedback mode is not activated
between the call to gl:beginQuery and gl:endQuery, the counter will not be
incremented. When gl:endQuery is executed, the primitives-written counter is
assigned to the query object's result value. This value can be queried by calling
gl:getQueryObjectiv/2 with Pname ?GL_QUERY_RESULT.
If Target is ?GL_TIME_ELAPSED, Id must be an unused name, or the name of an
existing timer query object previously bound to the ?GL_TIME_ELAPSED query binding.
When gl:beginQuery is executed, the query object's time counter is reset to 0. When
gl:endQuery is executed, the elapsed server time that has passed since the call to
gl:beginQuery is written into the query object's time counter. This value can be
queried by calling gl:getQueryObjectiv/2 with Pname ?GL_QUERY_RESULT .
Querying the ?GL_QUERY_RESULT implicitly flushes the GL pipeline until the
rendering delimited by the query object has completed and the result is available.
?GL_QUERY_RESULT_AVAILABLE can be queried to determine if the result is immediately
available or if the rendering is not yet complete.
See external documentation.
endQuery(Target) -> ok
Types:
Target = enum()
See beginQuery/2
getQueryiv(Target, Pname) -> integer()
Types:
Target = enum()
Pname = enum()
glGetQuery
See external documentation.
getQueryObjectiv(Id, Pname) -> integer()
Types:
Id = integer()
Pname = enum()
Return parameters of a query object
gl:getQueryObject returns in Params a selected parameter of the query object
specified by Id .
Pname names a specific query object parameter. Pname can be as follows:
?GL_QUERY_RESULT: Params returns the value of the query object's passed samples
counter. The initial value is 0.
?GL_QUERY_RESULT_AVAILABLE: Params returns whether the passed samples counter is
immediately available. If a delay would occur waiting for the query result,
?GL_FALSE is returned. Otherwise, ?GL_TRUE is returned, which also indicates that
the results of all previous queries are available as well.
See external documentation.
getQueryObjectuiv(Id, Pname) -> integer()
Types:
Id = integer()
Pname = enum()
See getQueryObjectiv/2
bindBuffer(Target, Buffer) -> ok
Types:
Target = enum()
Buffer = integer()
Bind a named buffer object
gl:bindBuffer binds a buffer object to the specified buffer binding point. Calling
gl:bindBuffer with Target set to one of the accepted symbolic constants and Buffer
set to the name of a buffer object binds that buffer object name to the target. If
no buffer object with name Buffer exists, one is created with that name. When a
buffer object is bound to a target, the previous binding for that target is
automatically broken.
Buffer object names are unsigned integers. The value zero is reserved, but there is
no default buffer object for each buffer object target. Instead, Buffer set to zero
effectively unbinds any buffer object previously bound, and restores client memory
usage for that buffer object target (if supported for that target). Buffer object
names and the corresponding buffer object contents are local to the shared object
space of the current GL rendering context; two rendering contexts share buffer
object names only if they explicitly enable sharing between contexts through the
appropriate GL windows interfaces functions.
gl:genBuffers/1 must be used to generate a set of unused buffer object names.
The state of a buffer object immediately after it is first bound is an unmapped
zero-sized memory buffer with ?GL_READ_WRITE access and ?GL_STATIC_DRAW usage.
While a non-zero buffer object name is bound, GL operations on the target to which
it is bound affect the bound buffer object, and queries of the target to which it
is bound return state from the bound buffer object. While buffer object name zero
is bound, as in the initial state, attempts to modify or query state on the target
to which it is bound generates an ?GL_INVALID_OPERATION error.
When a non-zero buffer object is bound to the ?GL_ARRAY_BUFFER target, the vertex
array pointer parameter is interpreted as an offset within the buffer object
measured in basic machine units.
When a non-zero buffer object is bound to the ?GL_DRAW_INDIRECT_BUFFER target,
parameters for draws issued through gl:drawArraysIndirect/2 and
gl:drawElementsIndirect/3 are sourced from that buffer object.
While a non-zero buffer object is bound to the ?GL_ELEMENT_ARRAY_BUFFER target, the
indices parameter of gl:drawElements/4 , gl:drawElementsInstanced/5 ,
gl:drawElementsBaseVertex/5 , gl:drawRangeElements/6 ,
gl:drawRangeElementsBaseVertex/7 , see glMultiDrawElements , or see
glMultiDrawElementsBaseVertex is interpreted as an offset within the buffer object
measured in basic machine units.
While a non-zero buffer object is bound to the ?GL_PIXEL_PACK_BUFFER target, the
following commands are affected: gl:getCompressedTexImage/3 , gl:getTexImage/5 ,
and gl:readPixels/7 . The pointer parameter is interpreted as an offset within the
buffer object measured in basic machine units.
While a non-zero buffer object is bound to the ?GL_PIXEL_UNPACK_BUFFER target, the
following commands are affected: gl:compressedTexImage1D/7 ,
gl:compressedTexImage2D/8 , gl:compressedTexImage3D/9 ,
gl:compressedTexSubImage1D/7 , gl:compressedTexSubImage2D/9 ,
gl:compressedTexSubImage3D/11 , gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:texSubImage1D/7 , gl:texSubImage1D/7 , and gl:texSubImage1D/7
. The pointer parameter is interpreted as an offset within the buffer object
measured in basic machine units.
The buffer targets ?GL_COPY_READ_BUFFER and ?GL_COPY_WRITE_BUFFER are provided to
allow gl:copyBufferSubData/5 to be used without disturbing the state of other
bindings. However, gl:copyBufferSubData/5 may be used with any pair of buffer
binding points.
The ?GL_TRANSFORM_FEEDBACK_BUFFER buffer binding point may be passed to
gl:bindBuffer , but will not directly affect transform feedback state. Instead, the
indexed ?GL_TRANSFORM_FEEDBACK_BUFFER bindings must be used through a call to
gl:bindBufferBase/3 or gl:bindBufferRange/5 . This will affect the generic
?GL_TRANSFORM_FEEDABCK_BUFFER binding.
Likewise, the ?GL_UNIFORM_BUFFER and ?GL_ATOMIC_COUNTER_BUFFER buffer binding
points may be used, but do not directly affect uniform buffer or atomic counter
buffer state, respectively. gl:bindBufferBase/3 or gl:bindBufferRange/5 must be
used to bind a buffer to an indexed uniform buffer or atomic counter buffer binding
point.
A buffer object binding created with gl:bindBuffer remains active until a different
buffer object name is bound to the same target, or until the bound buffer object is
deleted with gl:deleteBuffers/1 .
Once created, a named buffer object may be re-bound to any target as often as
needed. However, the GL implementation may make choices about how to optimize the
storage of a buffer object based on its initial binding target.
See external documentation.
deleteBuffers(Buffers) -> ok
Types:
Buffers = [integer()]
Delete named buffer objects
gl:deleteBuffers deletes N buffer objects named by the elements of the array
Buffers . After a buffer object is deleted, it has no contents, and its name is
free for reuse (for example by gl:genBuffers/1 ). If a buffer object that is
currently bound is deleted, the binding reverts to 0 (the absence of any buffer
object).
gl:deleteBuffers silently ignores 0's and names that do not correspond to existing
buffer objects.
See external documentation.
genBuffers(N) -> [integer()]
Types:
N = integer()
Generate buffer object names
gl:genBuffers returns N buffer object names in Buffers . There is no guarantee that
the names form a contiguous set of integers; however, it is guaranteed that none of
the returned names was in use immediately before the call to gl:genBuffers .
Buffer object names returned by a call to gl:genBuffers are not returned by
subsequent calls, unless they are first deleted with gl:deleteBuffers/1 .
No buffer objects are associated with the returned buffer object names until they
are first bound by calling gl:bindBuffer/2 .
See external documentation.
isBuffer(Buffer) -> 0 | 1
Types:
Buffer = integer()
Determine if a name corresponds to a buffer object
gl:isBuffer returns ?GL_TRUE if Buffer is currently the name of a buffer object. If
Buffer is zero, or is a non-zero value that is not currently the name of a buffer
object, or if an error occurs, gl:isBuffer returns ?GL_FALSE .
A name returned by gl:genBuffers/1 , but not yet associated with a buffer object by
calling gl:bindBuffer/2 , is not the name of a buffer object.
See external documentation.
bufferData(Target, Size, Data, Usage) -> ok
Types:
Target = enum()
Size = integer()
Data = offset() | mem()
Usage = enum()
Creates and initializes a buffer object's data store
gl:bufferData creates a new data store for the buffer object currently bound to
Target . Any pre-existing data store is deleted. The new data store is created with
the specified Size in bytes and Usage . If Data is not ?NULL, the data store is
initialized with data from this pointer. In its initial state, the new data store
is not mapped, it has a ?NULL mapped pointer, and its mapped access is
?GL_READ_WRITE .
Usage is a hint to the GL implementation as to how a buffer object's data store
will be accessed. This enables the GL implementation to make more intelligent
decisions that may significantly impact buffer object performance. It does not,
however, constrain the actual usage of the data store. Usage can be broken down
into two parts: first, the frequency of access (modification and usage), and
second, the nature of that access. The frequency of access may be one of these:
STREAM: The data store contents will be modified once and used at most a few times.
STATIC: The data store contents will be modified once and used many times.
DYNAMIC: The data store contents will be modified repeatedly and used many times.
The nature of access may be one of these:
DRAW: The data store contents are modified by the application, and used as the
source for GL drawing and image specification commands.
READ: The data store contents are modified by reading data from the GL, and used to
return that data when queried by the application.
COPY: The data store contents are modified by reading data from the GL, and used as
the source for GL drawing and image specification commands.
See external documentation.
bufferSubData(Target, Offset, Size, Data) -> ok
Types:
Target = enum()
Offset = integer()
Size = integer()
Data = offset() | mem()
Updates a subset of a buffer object's data store
gl:bufferSubData redefines some or all of the data store for the buffer object
currently bound to Target . Data starting at byte offset Offset and extending for
Size bytes is copied to the data store from the memory pointed to by Data . An
error is thrown if Offset and Size together define a range beyond the bounds of the
buffer object's data store.
See external documentation.
getBufferSubData(Target, Offset, Size, Data) -> ok
Types:
Target = enum()
Offset = integer()
Size = integer()
Data = mem()
Returns a subset of a buffer object's data store
gl:getBufferSubData returns some or all of the data from the buffer object
currently bound to Target . Data starting at byte offset Offset and extending for
Size bytes is copied from the data store to the memory pointed to by Data . An
error is thrown if the buffer object is currently mapped, or if Offset and Size
together define a range beyond the bounds of the buffer object's data store.
See external documentation.
getBufferParameteriv(Target, Pname) -> integer()
Types:
Target = enum()
Pname = enum()
Return parameters of a buffer object
gl:getBufferParameteriv returns in Data a selected parameter of the buffer object
specified by Target .
Value names a specific buffer object parameter, as follows:
?GL_BUFFER_ACCESS: Params returns the access policy set while mapping the buffer
object. The initial value is ?GL_READ_WRITE.
?GL_BUFFER_MAPPED: Params returns a flag indicating whether the buffer object is
currently mapped. The initial value is ?GL_FALSE.
?GL_BUFFER_SIZE: Params returns the size of the buffer object, measured in bytes.
The initial value is 0.
?GL_BUFFER_USAGE: Params returns the buffer object's usage pattern. The initial
value is ?GL_STATIC_DRAW.
See external documentation.
blendEquationSeparate(ModeRGB, ModeAlpha) -> ok
Types:
ModeRGB = enum()
ModeAlpha = enum()
Set the RGB blend equation and the alpha blend equation separately
The blend equations determines how a new pixel (the ''source'' color) is combined
with a pixel already in the framebuffer (the ''destination'' color). These
functions specifie one blend equation for the RGB-color components and one blend
equation for the alpha component. gl:blendEquationSeparatei specifies the blend
equations for a single draw buffer whereas gl:blendEquationSeparate sets the blend
equations for all draw buffers.
The blend equations use the source and destination blend factors specified by
either gl:blendFunc/2 or gl:blendFuncSeparate/4 . See gl:blendFunc/2 or
gl:blendFuncSeparate/4 for a description of the various blend factors.
In the equations that follow, source and destination color components are referred
to as (R s G s B s A s) and (R d G d B d A d), respectively. The result color is
referred to as (R r G r B r A r). The source and destination blend factors are
denoted (s R s G s B s A) and (d R d G d B d A), respectively. For these equations
all color components are understood to have values in the range [0 1].ModeRGB
ComponentsAlpha Component
?GL_FUNC_ADD Rr=R s s R+R d d R Gr=G s s G+G d d G Br=B s s B+B d d B Ar=A s s A+A
d d A
?GL_FUNC_SUBTRACT Rr=R s s R-R d d R Gr=G s s G-G d d G Br=B s s B-B d d B Ar=A s s
A-A d d A
?GL_FUNC_REVERSE_SUBTRACT Rr=R d d R-R s s R Gr=G d d G-G s s G Br=B d d B-B s s B
Ar=A d d A-A s s A
?GL_MIN Rr=min(R s R d) Gr=min(G s G d) Br=min(B s B d) Ar=min (A s A d)
?GL_MAX Rr=max(R s R d) Gr=max(G s G d) Br=max(B s B d) Ar=max(A s A d)
The results of these equations are clamped to the range [0 1].
The ?GL_MIN and ?GL_MAX equations are useful for applications that analyze image
data (image thresholding against a constant color, for example). The ?GL_FUNC_ADD
equation is useful for antialiasing and transparency, among other things.
Initially, both the RGB blend equation and the alpha blend equation are set to
?GL_FUNC_ADD .
See external documentation.
drawBuffers(Bufs) -> ok
Types:
Bufs = [enum()]
Specifies a list of color buffers to be drawn into
gl:drawBuffers defines an array of buffers into which outputs from the fragment
shader data will be written. If a fragment shader writes a value to one or more
user defined output variables, then the value of each variable will be written into
the buffer specified at a location within Bufs corresponding to the location
assigned to that user defined output. The draw buffer used for user defined outputs
assigned to locations greater than or equal to N is implicitly set to ?GL_NONE and
any data written to such an output is discarded.
The symbolic constants contained in Bufs may be any of the following:
?GL_NONE: The fragment shader output value is not written into any color buffer.
?GL_FRONT_LEFT: The fragment shader output value is written into the front left
color buffer.
?GL_FRONT_RIGHT: The fragment shader output value is written into the front right
color buffer.
?GL_BACK_LEFT: The fragment shader output value is written into the back left color
buffer.
?GL_BACK_RIGHT: The fragment shader output value is written into the back right
color buffer.
?GL_COLOR_ATTACHMENTn: The fragment shader output value is written into the nth
color attachment of the current framebuffer. n may range from 0 to the value of
?GL_MAX_COLOR_ATTACHMENTS.
Except for ?GL_NONE, the preceding symbolic constants may not appear more than once
in Bufs . The maximum number of draw buffers supported is implementation dependent
and can be queried by calling gl:getBooleanv/1 with the argument
?GL_MAX_DRAW_BUFFERS .
See external documentation.
stencilOpSeparate(Face, Sfail, Dpfail, Dppass) -> ok
Types:
Face = enum()
Sfail = enum()
Dpfail = enum()
Dppass = enum()
Set front and/or back stencil test actions
Stenciling, like depth-buffering, enables and disables drawing on a per-pixel
basis. You draw into the stencil planes using GL drawing primitives, then render
geometry and images, using the stencil planes to mask out portions of the screen.
Stenciling is typically used in multipass rendering algorithms to achieve special
effects, such as decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome of a
comparison between the value in the stencil buffer and a reference value. To enable
and disable the test, call gl:enable/1 and gl:enable/1 with argument
?GL_STENCIL_TEST ; to control it, call gl:stencilFunc/3 or gl:stencilFuncSeparate/4
.
There can be two separate sets of Sfail , Dpfail , and Dppass parameters; one
affects back-facing polygons, and the other affects front-facing polygons as well
as other non-polygon primitives. gl:stencilOp/3 sets both front and back stencil
state to the same values, as if gl:stencilOpSeparate/4 were called with Face set to
?GL_FRONT_AND_BACK.
gl:stencilOpSeparate takes three arguments that indicate what happens to the stored
stencil value while stenciling is enabled. If the stencil test fails, no change is
made to the pixel's color or depth buffers, and Sfail specifies what happens to the
stencil buffer contents. The following eight actions are possible.
?GL_KEEP: Keeps the current value.
?GL_ZERO: Sets the stencil buffer value to 0.
?GL_REPLACE: Sets the stencil buffer value to ref, as specified by gl:stencilFunc/3
.
?GL_INCR: Increments the current stencil buffer value. Clamps to the maximum
representable unsigned value.
?GL_INCR_WRAP: Increments the current stencil buffer value. Wraps stencil buffer
value to zero when incrementing the maximum representable unsigned value.
?GL_DECR: Decrements the current stencil buffer value. Clamps to 0.
?GL_DECR_WRAP: Decrements the current stencil buffer value. Wraps stencil buffer
value to the maximum representable unsigned value when decrementing a stencil
buffer value of zero.
?GL_INVERT: Bitwise inverts the current stencil buffer value.
Stencil buffer values are treated as unsigned integers. When incremented and
decremented, values are clamped to 0 and 2 n-1, where n is the value returned by
querying ?GL_STENCIL_BITS .
The other two arguments to gl:stencilOpSeparate specify stencil buffer actions that
depend on whether subsequent depth buffer tests succeed ( Dppass ) or fail ( Dpfail
) (see gl:depthFunc/1 ). The actions are specified using the same eight symbolic
constants as Sfail . Note that Dpfail is ignored when there is no depth buffer, or
when the depth buffer is not enabled. In these cases, Sfail and Dppass specify
stencil action when the stencil test fails and passes, respectively.
See external documentation.
stencilFuncSeparate(Face, Func, Ref, Mask) -> ok
Types:
Face = enum()
Func = enum()
Ref = integer()
Mask = integer()
Set front and/or back function and reference value for stencil testing
Stenciling, like depth-buffering, enables and disables drawing on a per-pixel
basis. You draw into the stencil planes using GL drawing primitives, then render
geometry and images, using the stencil planes to mask out portions of the screen.
Stenciling is typically used in multipass rendering algorithms to achieve special
effects, such as decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome of a
comparison between the reference value and the value in the stencil buffer. To
enable and disable the test, call gl:enable/1 and gl:enable/1 with argument
?GL_STENCIL_TEST . To specify actions based on the outcome of the stencil test,
call gl:stencilOp/3 or gl:stencilOpSeparate/4 .
There can be two separate sets of Func , Ref , and Mask parameters; one affects
back-facing polygons, and the other affects front-facing polygons as well as other
non-polygon primitives. gl:stencilFunc/3 sets both front and back stencil state to
the same values, as if gl:stencilFuncSeparate/4 were called with Face set to
?GL_FRONT_AND_BACK.
Func is a symbolic constant that determines the stencil comparison function. It
accepts one of eight values, shown in the following list. Ref is an integer
reference value that is used in the stencil comparison. It is clamped to the range
[0 2 n-1], where n is the number of bitplanes in the stencil buffer. Mask is
bitwise ANDed with both the reference value and the stored stencil value, with the
ANDed values participating in the comparison.
If stencil represents the value stored in the corresponding stencil buffer
location, the following list shows the effect of each comparison function that can
be specified by Func . Only if the comparison succeeds is the pixel passed through
to the next stage in the rasterization process (see gl:stencilOp/3 ). All tests
treat stencil values as unsigned integers in the range [0 2 n-1], where n is the
number of bitplanes in the stencil buffer.
The following values are accepted by Func :
?GL_NEVER: Always fails.
?GL_LESS: Passes if ( Ref & Mask ) < ( stencil & Mask ).
?GL_LEQUAL: Passes if ( Ref & Mask ) <= ( stencil & Mask ).
?GL_GREATER: Passes if ( Ref & Mask ) > ( stencil & Mask ).
?GL_GEQUAL: Passes if ( Ref & Mask ) >= ( stencil & Mask ).
?GL_EQUAL: Passes if ( Ref & Mask ) = ( stencil & Mask ).
?GL_NOTEQUAL: Passes if ( Ref & Mask ) != ( stencil & Mask ).
?GL_ALWAYS: Always passes.
See external documentation.
stencilMaskSeparate(Face, Mask) -> ok
Types:
Face = enum()
Mask = integer()
Control the front and/or back writing of individual bits in the stencil planes
gl:stencilMaskSeparate controls the writing of individual bits in the stencil
planes. The least significant n bits of Mask , where n is the number of bits in the
stencil buffer, specify a mask. Where a 1 appears in the mask, it's possible to
write to the corresponding bit in the stencil buffer. Where a 0 appears, the
corresponding bit is write-protected. Initially, all bits are enabled for writing.
There can be two separate Mask writemasks; one affects back-facing polygons, and
the other affects front-facing polygons as well as other non-polygon primitives.
gl:stencilMask/1 sets both front and back stencil writemasks to the same values, as
if gl:stencilMaskSeparate/2 were called with Face set to ?GL_FRONT_AND_BACK.
See external documentation.
attachShader(Program, Shader) -> ok
Types:
Program = integer()
Shader = integer()
Attaches a shader object to a program object
In order to create a complete shader program, there must be a way to specify the
list of things that will be linked together. Program objects provide this
mechanism. Shaders that are to be linked together in a program object must first be
attached to that program object. gl:attachShader attaches the shader object
specified by Shader to the program object specified by Program . This indicates
that Shader will be included in link operations that will be performed on Program .
All operations that can be performed on a shader object are valid whether or not
the shader object is attached to a program object. It is permissible to attach a
shader object to a program object before source code has been loaded into the
shader object or before the shader object has been compiled. It is permissible to
attach multiple shader objects of the same type because each may contain a portion
of the complete shader. It is also permissible to attach a shader object to more
than one program object. If a shader object is deleted while it is attached to a
program object, it will be flagged for deletion, and deletion will not occur until
gl:detachShader/2 is called to detach it from all program objects to which it is
attached.
See external documentation.
bindAttribLocation(Program, Index, Name) -> ok
Types:
Program = integer()
Index = integer()
Name = string()
Associates a generic vertex attribute index with a named attribute variable
gl:bindAttribLocation is used to associate a user-defined attribute variable in the
program object specified by Program with a generic vertex attribute index. The name
of the user-defined attribute variable is passed as a null terminated string in
Name . The generic vertex attribute index to be bound to this variable is specified
by Index . When Program is made part of current state, values provided via the
generic vertex attribute Index will modify the value of the user-defined attribute
variable specified by Name .
If Name refers to a matrix attribute variable, Index refers to the first column of
the matrix. Other matrix columns are then automatically bound to locations Index+1
for a matrix of type mat2; Index+1 and Index+2 for a matrix of type mat3; and
Index+1 , Index+2 , and Index+3 for a matrix of type mat4 .
This command makes it possible for vertex shaders to use descriptive names for
attribute variables rather than generic variables that are numbered from 0 to
?GL_MAX_VERTEX_ATTRIBS -1. The values sent to each generic attribute index are part
of current state. If a different program object is made current by calling
gl:useProgram/1 , the generic vertex attributes are tracked in such a way that the
same values will be observed by attributes in the new program object that are also
bound to Index .
Attribute variable name-to-generic attribute index bindings for a program object
can be explicitly assigned at any time by calling gl:bindAttribLocation. Attribute
bindings do not go into effect until gl:linkProgram/1 is called. After a program
object has been linked successfully, the index values for generic attributes remain
fixed (and their values can be queried) until the next link command occurs.
Any attribute binding that occurs after the program object has been linked will not
take effect until the next time the program object is linked.
See external documentation.
compileShader(Shader) -> ok
Types:
Shader = integer()
Compiles a shader object
gl:compileShader compiles the source code strings that have been stored in the
shader object specified by Shader .
The compilation status will be stored as part of the shader object's state. This
value will be set to ?GL_TRUE if the shader was compiled without errors and is
ready for use, and ?GL_FALSE otherwise. It can be queried by calling
gl:getShaderiv/2 with arguments Shader and ?GL_COMPILE_STATUS.
Compilation of a shader can fail for a number of reasons as specified by the OpenGL
Shading Language Specification. Whether or not the compilation was successful,
information about the compilation can be obtained from the shader object's
information log by calling gl:getShaderInfoLog/2 .
See external documentation.
createProgram() -> integer()
Creates a program object
gl:createProgram creates an empty program object and returns a non-zero value by
which it can be referenced. A program object is an object to which shader objects
can be attached. This provides a mechanism to specify the shader objects that will
be linked to create a program. It also provides a means for checking the
compatibility of the shaders that will be used to create a program (for instance,
checking the compatibility between a vertex shader and a fragment shader). When no
longer needed as part of a program object, shader objects can be detached.
One or more executables are created in a program object by successfully attaching
shader objects to it with gl:attachShader/2 , successfully compiling the shader
objects with gl:compileShader/1 , and successfully linking the program object with
gl:linkProgram/1 . These executables are made part of current state when
gl:useProgram/1 is called. Program objects can be deleted by calling
gl:deleteProgram/1 . The memory associated with the program object will be deleted
when it is no longer part of current rendering state for any context.
See external documentation.
createShader(Type) -> integer()
Types:
Type = enum()
Creates a shader object
gl:createShader creates an empty shader object and returns a non-zero value by
which it can be referenced. A shader object is used to maintain the source code
strings that define a shader. ShaderType indicates the type of shader to be
created. Five types of shader are supported. A shader of type ?GL_VERTEX_SHADER is
a shader that is intended to run on the programmable vertex processor. A shader of
type ?GL_TESS_CONTROL_SHADER is a shader that is intended to run on the
programmable tessellation processor in the control stage. A shader of type
?GL_TESS_EVALUATION_SHADER is a shader that is intended to run on the programmable
tessellation processor in the evaluation stage. A shader of type
?GL_GEOMETRY_SHADER is a shader that is intended to run on the programmable
geometry processor. A shader of type ?GL_FRAGMENT_SHADER is a shader that is
intended to run on the programmable fragment processor.
When created, a shader object's ?GL_SHADER_TYPE parameter is set to either
?GL_VERTEX_SHADER , ?GL_TESS_CONTROL_SHADER, ?GL_TESS_EVALUATION_SHADER,
?GL_GEOMETRY_SHADER or ?GL_FRAGMENT_SHADER, depending on the value of ShaderType .
See external documentation.
deleteProgram(Program) -> ok
Types:
Program = integer()
Deletes a program object
gl:deleteProgram frees the memory and invalidates the name associated with the
program object specified by Program. This command effectively undoes the effects of
a call to gl:createProgram/0 .
If a program object is in use as part of current rendering state, it will be
flagged for deletion, but it will not be deleted until it is no longer part of
current state for any rendering context. If a program object to be deleted has
shader objects attached to it, those shader objects will be automatically detached
but not deleted unless they have already been flagged for deletion by a previous
call to gl:deleteShader/1 . A value of 0 for Program will be silently ignored.
To determine whether a program object has been flagged for deletion, call
gl:getProgramiv/2 with arguments Program and ?GL_DELETE_STATUS.
See external documentation.
deleteShader(Shader) -> ok
Types:
Shader = integer()
Deletes a shader object
gl:deleteShader frees the memory and invalidates the name associated with the
shader object specified by Shader . This command effectively undoes the effects of
a call to gl:createShader/1 .
If a shader object to be deleted is attached to a program object, it will be
flagged for deletion, but it will not be deleted until it is no longer attached to
any program object, for any rendering context (i.e., it must be detached from
wherever it was attached before it will be deleted). A value of 0 for Shader will
be silently ignored.
To determine whether an object has been flagged for deletion, call gl:getShaderiv/2
with arguments Shader and ?GL_DELETE_STATUS.
See external documentation.
detachShader(Program, Shader) -> ok
Types:
Program = integer()
Shader = integer()
Detaches a shader object from a program object to which it is attached
gl:detachShader detaches the shader object specified by Shader from the program
object specified by Program . This command can be used to undo the effect of the
command gl:attachShader/2 .
If Shader has already been flagged for deletion by a call to gl:deleteShader/1 and
it is not attached to any other program object, it will be deleted after it has
been detached.
See external documentation.
disableVertexAttribArray(Index) -> ok
Types:
Index = integer()
Enable or disable a generic vertex attribute array
gl:enableVertexAttribArray enables the generic vertex attribute array specified by
Index . gl:disableVertexAttribArray disables the generic vertex attribute array
specified by Index . By default, all client-side capabilities are disabled,
including all generic vertex attribute arrays. If enabled, the values in the
generic vertex attribute array will be accessed and used for rendering when calls
are made to vertex array commands such as gl:drawArrays/3 , gl:drawElements/4 ,
gl:drawRangeElements/6 , see glMultiDrawElements , or gl:multiDrawArrays/3 .
See external documentation.
enableVertexAttribArray(Index) -> ok
Types:
Index = integer()
See disableVertexAttribArray/1
getActiveAttrib(Program, Index, BufSize) -> {Size::integer(), Type::enum(),
Name::string()}
Types:
Program = integer()
Index = integer()
BufSize = integer()
Returns information about an active attribute variable for the specified program
object
gl:getActiveAttrib returns information about an active attribute variable in the
program object specified by Program . The number of active attributes can be
obtained by calling gl:getProgramiv/2 with the value ?GL_ACTIVE_ATTRIBUTES. A value
of 0 for Index selects the first active attribute variable. Permissible values for
Index range from 0 to the number of active attribute variables minus 1.
A vertex shader may use either built-in attribute variables, user-defined attribute
variables, or both. Built-in attribute variables have a prefix of "gl_" and
reference conventional OpenGL vertex attribtes (e.g., Gl_Vertex , Gl_Normal , etc.,
see the OpenGL Shading Language specification for a complete list.) User-defined
attribute variables have arbitrary names and obtain their values through numbered
generic vertex attributes. An attribute variable (either built-in or user-defined)
is considered active if it is determined during the link operation that it may be
accessed during program execution. Therefore, Program should have previously been
the target of a call to gl:linkProgram/1 , but it is not necessary for it to have
been linked successfully.
The size of the character buffer required to store the longest attribute variable
name in Program can be obtained by calling gl:getProgramiv/2 with the value
?GL_ACTIVE_ATTRIBUTE_MAX_LENGTH . This value should be used to allocate a buffer of
sufficient size to store the returned attribute name. The size of this character
buffer is passed in BufSize , and a pointer to this character buffer is passed in
Name .
gl:getActiveAttrib returns the name of the attribute variable indicated by Index ,
storing it in the character buffer specified by Name . The string returned will be
null terminated. The actual number of characters written into this buffer is
returned in Length , and this count does not include the null termination
character. If the length of the returned string is not required, a value of ?NULL
can be passed in the Length argument.
The Type argument specifies a pointer to a variable into which the attribute
variable's data type will be written. The symbolic constants ?GL_FLOAT,
?GL_FLOAT_VEC2, ?GL_FLOAT_VEC3, ?GL_FLOAT_VEC4, ?GL_FLOAT_MAT2, ?GL_FLOAT_MAT3,
?GL_FLOAT_MAT4, ?GL_FLOAT_MAT2x3, ?GL_FLOAT_MAT2x4, ?GL_FLOAT_MAT3x2 ,
?GL_FLOAT_MAT3x4, ?GL_FLOAT_MAT4x2, ?GL_FLOAT_MAT4x3, ?GL_INT , ?GL_INT_VEC2,
?GL_INT_VEC3, ?GL_INT_VEC4, ?GL_UNSIGNED_INT_VEC , ?GL_UNSIGNED_INT_VEC2,
?GL_UNSIGNED_INT_VEC3, ?GL_UNSIGNED_INT_VEC4, ?DOUBLE, ?DOUBLE_VEC2, ?DOUBLE_VEC3,
?DOUBLE_VEC4, ?DOUBLE_MAT2 , ?DOUBLE_MAT3, ?DOUBLE_MAT4, ?DOUBLE_MAT2x3,
?DOUBLE_MAT2x4, ?DOUBLE_MAT3x2, ?DOUBLE_MAT3x4, ?DOUBLE_MAT4x2, or ?DOUBLE_MAT4x3
may be returned. The Size argument will return the size of the attribute, in units
of the type returned in Type .
The list of active attribute variables may include both built-in attribute
variables (which begin with the prefix "gl_") as well as user-defined attribute
variable names.
This function will return as much information as it can about the specified active
attribute variable. If no information is available, Length will be 0, and Name will
be an empty string. This situation could occur if this function is called after a
link operation that failed. If an error occurs, the return values Length , Size ,
Type , and Name will be unmodified.
See external documentation.
getActiveUniform(Program, Index, BufSize) -> {Size::integer(), Type::enum(),
Name::string()}
Types:
Program = integer()
Index = integer()
BufSize = integer()
Returns information about an active uniform variable for the specified program
object
gl:getActiveUniform returns information about an active uniform variable in the
program object specified by Program . The number of active uniform variables can be
obtained by calling gl:getProgramiv/2 with the value ?GL_ACTIVE_UNIFORMS. A value
of 0 for Index selects the first active uniform variable. Permissible values for
Index range from 0 to the number of active uniform variables minus 1.
Shaders may use either built-in uniform variables, user-defined uniform variables,
or both. Built-in uniform variables have a prefix of "gl_" and reference existing
OpenGL state or values derived from such state (e.g., Gl_DepthRangeParameters , see
the OpenGL Shading Language specification for a complete list.) User-defined
uniform variables have arbitrary names and obtain their values from the application
through calls to gl:uniform1f/2 . A uniform variable (either built-in or user-
defined) is considered active if it is determined during the link operation that it
may be accessed during program execution. Therefore, Program should have previously
been the target of a call to gl:linkProgram/1 , but it is not necessary for it to
have been linked successfully.
The size of the character buffer required to store the longest uniform variable
name in Program can be obtained by calling gl:getProgramiv/2 with the value
?GL_ACTIVE_UNIFORM_MAX_LENGTH . This value should be used to allocate a buffer of
sufficient size to store the returned uniform variable name. The size of this
character buffer is passed in BufSize , and a pointer to this character buffer is
passed in Name.
gl:getActiveUniform returns the name of the uniform variable indicated by Index ,
storing it in the character buffer specified by Name . The string returned will be
null terminated. The actual number of characters written into this buffer is
returned in Length , and this count does not include the null termination
character. If the length of the returned string is not required, a value of ?NULL
can be passed in the Length argument.
The Type argument will return a pointer to the uniform variable's data type. The
symbolic constants returned for uniform types are shown in the table below.Returned
Symbolic ContantShader Uniform Type
?GL_FLOAT?float
?GL_FLOAT_VEC2?vec2
?GL_FLOAT_VEC3?vec3
?GL_FLOAT_VEC4?vec4
?GL_DOUBLE?double
?GL_DOUBLE_VEC2?dvec2
?GL_DOUBLE_VEC3?dvec3
?GL_DOUBLE_VEC4?dvec4
?GL_INT?int
?GL_INT_VEC2?ivec2
?GL_INT_VEC3?ivec3
?GL_INT_VEC4?ivec4
?GL_UNSIGNED_INT?unsigned int
?GL_UNSIGNED_INT_VEC2?uvec2
?GL_UNSIGNED_INT_VEC3?uvec3
?GL_UNSIGNED_INT_VEC4?uvec4
?GL_BOOL?bool
?GL_BOOL_VEC2?bvec2
?GL_BOOL_VEC3?bvec3
?GL_BOOL_VEC4?bvec4
?GL_FLOAT_MAT2?mat2
?GL_FLOAT_MAT3?mat3
?GL_FLOAT_MAT4?mat4
?GL_FLOAT_MAT2x3?mat2x3
?GL_FLOAT_MAT2x4?mat2x4
?GL_FLOAT_MAT3x2?mat3x2
?GL_FLOAT_MAT3x4?mat3x4
?GL_FLOAT_MAT4x2?mat4x2
?GL_FLOAT_MAT4x3?mat4x3
?GL_DOUBLE_MAT2?dmat2
?GL_DOUBLE_MAT3?dmat3
?GL_DOUBLE_MAT4?dmat4
?GL_DOUBLE_MAT2x3?dmat2x3
?GL_DOUBLE_MAT2x4?dmat2x4
?GL_DOUBLE_MAT3x2?dmat3x2
?GL_DOUBLE_MAT3x4?dmat3x4
?GL_DOUBLE_MAT4x2?dmat4x2
?GL_DOUBLE_MAT4x3?dmat4x3
?GL_SAMPLER_1D?sampler1D
?GL_SAMPLER_2D?sampler2D
?GL_SAMPLER_3D?sampler3D
?GL_SAMPLER_CUBE?samplerCube
?GL_SAMPLER_1D_SHADOW?sampler1DShadow
?GL_SAMPLER_2D_SHADOW?sampler2DShadow
?GL_SAMPLER_1D_ARRAY?sampler1DArray
?GL_SAMPLER_2D_ARRAY?sampler2DArray
?GL_SAMPLER_1D_ARRAY_SHADOW?sampler1DArrayShadow
?GL_SAMPLER_2D_ARRAY_SHADOW?sampler2DArrayShadow
?GL_SAMPLER_2D_MULTISAMPLE?sampler2DMS
?GL_SAMPLER_2D_MULTISAMPLE_ARRAY?sampler2DMSArray
?GL_SAMPLER_CUBE_SHADOW?samplerCubeShadow
?GL_SAMPLER_BUFFER?samplerBuffer
?GL_SAMPLER_2D_RECT?sampler2DRect
?GL_SAMPLER_2D_RECT_SHADOW?sampler2DRectShadow
?GL_INT_SAMPLER_1D?isampler1D
?GL_INT_SAMPLER_2D?isampler2D
?GL_INT_SAMPLER_3D?isampler3D
?GL_INT_SAMPLER_CUBE?isamplerCube
?GL_INT_SAMPLER_1D_ARRAY?isampler1DArray
?GL_INT_SAMPLER_2D_ARRAY?isampler2DArray
?GL_INT_SAMPLER_2D_MULTISAMPLE?isampler2DMS
?GL_INT_SAMPLER_2D_MULTISAMPLE_ARRAY?isampler2DMSArray
?GL_INT_SAMPLER_BUFFER?isamplerBuffer
?GL_INT_SAMPLER_2D_RECT?isampler2DRect
?GL_UNSIGNED_INT_SAMPLER_1D?usampler1D
?GL_UNSIGNED_INT_SAMPLER_2D?usampler2D
?GL_UNSIGNED_INT_SAMPLER_3D?usampler3D
?GL_UNSIGNED_INT_SAMPLER_CUBE?usamplerCube
?GL_UNSIGNED_INT_SAMPLER_1D_ARRAY?usampler2DArray
?GL_UNSIGNED_INT_SAMPLER_2D_ARRAY?usampler2DArray
?GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE?usampler2DMS
?GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE_ARRAY?usampler2DMSArray
?GL_UNSIGNED_INT_SAMPLER_BUFFER?usamplerBuffer
?GL_UNSIGNED_INT_SAMPLER_2D_RECT?usampler2DRect
?GL_IMAGE_1D?image1D
?GL_IMAGE_2D?image2D
?GL_IMAGE_3D?image3D
?GL_IMAGE_2D_RECT?image2DRect
?GL_IMAGE_CUBE?imageCube
?GL_IMAGE_BUFFER?imageBuffer
?GL_IMAGE_1D_ARRAY?image1DArray
?GL_IMAGE_2D_ARRAY?image2DArray
?GL_IMAGE_2D_MULTISAMPLE?image2DMS
?GL_IMAGE_2D_MULTISAMPLE_ARRAY?image2DMSArray
?GL_INT_IMAGE_1D?iimage1D
?GL_INT_IMAGE_2D?iimage2D
?GL_INT_IMAGE_3D?iimage3D
?GL_INT_IMAGE_2D_RECT?iimage2DRect
?GL_INT_IMAGE_CUBE?iimageCube
?GL_INT_IMAGE_BUFFER?iimageBuffer
?GL_INT_IMAGE_1D_ARRAY?iimage1DArray
?GL_INT_IMAGE_2D_ARRAY?iimage2DArray
?GL_INT_IMAGE_2D_MULTISAMPLE?iimage2DMS
?GL_INT_IMAGE_2D_MULTISAMPLE_ARRAY?iimage2DMSArray
?GL_UNSIGNED_INT_IMAGE_1D?uimage1D
?GL_UNSIGNED_INT_IMAGE_2D?uimage2D
?GL_UNSIGNED_INT_IMAGE_3D?uimage3D
?GL_UNSIGNED_INT_IMAGE_2D_RECT?uimage2DRect
?GL_UNSIGNED_INT_IMAGE_CUBE?uimageCube
?GL_UNSIGNED_INT_IMAGE_BUFFER?uimageBuffer
?GL_UNSIGNED_INT_IMAGE_1D_ARRAY?uimage1DArray
?GL_UNSIGNED_INT_IMAGE_2D_ARRAY?uimage2DArray
?GL_UNSIGNED_INT_IMAGE_2D_MULTISAMPLE?uimage2DMS
?GL_UNSIGNED_INT_IMAGE_2D_MULTISAMPLE_ARRAY?uimage2DMSArray
?GL_UNSIGNED_INT_ATOMIC_COUNTER?atomic_uint
If one or more elements of an array are active, the name of the array is returned
in Name , the type is returned in Type , and the Size parameter returns the highest
array element index used, plus one, as determined by the compiler and/or linker.
Only one active uniform variable will be reported for a uniform array.
Uniform variables that are declared as structures or arrays of structures will not
be returned directly by this function. Instead, each of these uniform variables
will be reduced to its fundamental components containing the "." and "[]" operators
such that each of the names is valid as an argument to gl:getUniformLocation/2 .
Each of these reduced uniform variables is counted as one active uniform variable
and is assigned an index. A valid name cannot be a structure, an array of
structures, or a subcomponent of a vector or matrix.
The size of the uniform variable will be returned in Size . Uniform variables other
than arrays will have a size of 1. Structures and arrays of structures will be
reduced as described earlier, such that each of the names returned will be a data
type in the earlier list. If this reduction results in an array, the size returned
will be as described for uniform arrays; otherwise, the size returned will be 1.
The list of active uniform variables may include both built-in uniform variables
(which begin with the prefix "gl_") as well as user-defined uniform variable names.
This function will return as much information as it can about the specified active
uniform variable. If no information is available, Length will be 0, and Name will
be an empty string. This situation could occur if this function is called after a
link operation that failed. If an error occurs, the return values Length , Size ,
Type , and Name will be unmodified.
See external documentation.
getAttachedShaders(Program, MaxCount) -> [integer()]
Types:
Program = integer()
MaxCount = integer()
Returns the handles of the shader objects attached to a program object
gl:getAttachedShaders returns the names of the shader objects attached to Program .
The names of shader objects that are attached to Program will be returned in
Shaders. The actual number of shader names written into Shaders is returned in
Count. If no shader objects are attached to Program , Count is set to 0. The
maximum number of shader names that may be returned in Shaders is specified by
MaxCount .
If the number of names actually returned is not required (for instance, if it has
just been obtained by calling gl:getProgramiv/2 ), a value of ?NULL may be passed
for count. If no shader objects are attached to Program , a value of 0 will be
returned in Count . The actual number of attached shaders can be obtained by
calling gl:getProgramiv/2 with the value ?GL_ATTACHED_SHADERS.
See external documentation.
getAttribLocation(Program, Name) -> integer()
Types:
Program = integer()
Name = string()
Returns the location of an attribute variable
gl:getAttribLocation queries the previously linked program object specified by
Program for the attribute variable specified by Name and returns the index of the
generic vertex attribute that is bound to that attribute variable. If Name is a
matrix attribute variable, the index of the first column of the matrix is returned.
If the named attribute variable is not an active attribute in the specified program
object or if Name starts with the reserved prefix "gl_", a value of -1 is returned.
The association between an attribute variable name and a generic attribute index
can be specified at any time by calling gl:bindAttribLocation/3 . Attribute
bindings do not go into effect until gl:linkProgram/1 is called. After a program
object has been linked successfully, the index values for attribute variables
remain fixed until the next link command occurs. The attribute values can only be
queried after a link if the link was successful. gl:getAttribLocation returns the
binding that actually went into effect the last time gl:linkProgram/1 was called
for the specified program object. Attribute bindings that have been specified since
the last link operation are not returned by gl:getAttribLocation.
See external documentation.
getProgramiv(Program, Pname) -> integer()
Types:
Program = integer()
Pname = enum()
Returns a parameter from a program object
gl:getProgram returns in Params the value of a parameter for a specific program
object. The following parameters are defined:
?GL_DELETE_STATUS: Params returns ?GL_TRUE if Program is currently flagged for
deletion, and ?GL_FALSE otherwise.
?GL_LINK_STATUS: Params returns ?GL_TRUE if the last link operation on Program was
successful, and ?GL_FALSE otherwise.
?GL_VALIDATE_STATUS: Params returns ?GL_TRUE or if the last validation operation on
Program was successful, and ?GL_FALSE otherwise.
?GL_INFO_LOG_LENGTH: Params returns the number of characters in the information log
for Program including the null termination character (i.e., the size of the
character buffer required to store the information log). If Program has no
information log, a value of 0 is returned.
?GL_ATTACHED_SHADERS: Params returns the number of shader objects attached to
Program .
?GL_ACTIVE_ATOMIC_COUNTER_BUFFERS: Params returns the number of active attribute
atomic counter buffers used by Program .
?GL_ACTIVE_ATTRIBUTES: Params returns the number of active attribute variables for
Program .
?GL_ACTIVE_ATTRIBUTE_MAX_LENGTH: Params returns the length of the longest active
attribute name for Program , including the null termination character (i.e., the
size of the character buffer required to store the longest attribute name). If no
active attributes exist, 0 is returned.
?GL_ACTIVE_UNIFORMS: Params returns the number of active uniform variables for
Program .
?GL_ACTIVE_UNIFORM_MAX_LENGTH: Params returns the length of the longest active
uniform variable name for Program , including the null termination character (i.e.,
the size of the character buffer required to store the longest uniform variable
name). If no active uniform variables exist, 0 is returned.
?GL_PROGRAM_BINARY_LENGTH: Params returns the length of the program binary, in
bytes that will be returned by a call to gl:getProgramBinary/2 . When a progam's
?GL_LINK_STATUS is ?GL_FALSE, its program binary length is zero.
?GL_TRANSFORM_FEEDBACK_BUFFER_MODE: Params returns a symbolic constant indicating
the buffer mode used when transform feedback is active. This may be
?GL_SEPARATE_ATTRIBS or ?GL_INTERLEAVED_ATTRIBS.
?GL_TRANSFORM_FEEDBACK_VARYINGS: Params returns the number of varying variables to
capture in transform feedback mode for the program.
?GL_TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH: Params returns the length of the longest
variable name to be used for transform feedback, including the null-terminator.
?GL_GEOMETRY_VERTICES_OUT: Params returns the maximum number of vertices that the
geometry shader in Program will output.
?GL_GEOMETRY_INPUT_TYPE: Params returns a symbolic constant indicating the
primitive type accepted as input to the geometry shader contained in Program .
?GL_GEOMETRY_OUTPUT_TYPE: Params returns a symbolic constant indicating the
primitive type that will be output by the geometry shader contained in Program .
See external documentation.
getProgramInfoLog(Program, BufSize) -> string()
Types:
Program = integer()
BufSize = integer()
Returns the information log for a program object
gl:getProgramInfoLog returns the information log for the specified program object.
The information log for a program object is modified when the program object is
linked or validated. The string that is returned will be null terminated.
gl:getProgramInfoLog returns in InfoLog as much of the information log as it can,
up to a maximum of MaxLength characters. The number of characters actually
returned, excluding the null termination character, is specified by Length . If the
length of the returned string is not required, a value of ?NULL can be passed in
the Length argument. The size of the buffer required to store the returned
information log can be obtained by calling gl:getProgramiv/2 with the value
?GL_INFO_LOG_LENGTH .
The information log for a program object is either an empty string, or a string
containing information about the last link operation, or a string containing
information about the last validation operation. It may contain diagnostic
messages, warning messages, and other information. When a program object is
created, its information log will be a string of length 0.
See external documentation.
getShaderiv(Shader, Pname) -> integer()
Types:
Shader = integer()
Pname = enum()
Returns a parameter from a shader object
gl:getShader returns in Params the value of a parameter for a specific shader
object. The following parameters are defined:
?GL_SHADER_TYPE: Params returns ?GL_VERTEX_SHADER if Shader is a vertex shader
object, ?GL_GEOMETRY_SHADER if Shader is a geometry shader object, and
?GL_FRAGMENT_SHADER if Shader is a fragment shader object.
?GL_DELETE_STATUS: Params returns ?GL_TRUE if Shader is currently flagged for
deletion, and ?GL_FALSE otherwise.
?GL_COMPILE_STATUS: Params returns ?GL_TRUE if the last compile operation on Shader
was successful, and ?GL_FALSE otherwise.
?GL_INFO_LOG_LENGTH: Params returns the number of characters in the information log
for Shader including the null termination character (i.e., the size of the
character buffer required to store the information log). If Shader has no
information log, a value of 0 is returned.
?GL_SHADER_SOURCE_LENGTH: Params returns the length of the concatenation of the
source strings that make up the shader source for the Shader , including the null
termination character. (i.e., the size of the character buffer required to store
the shader source). If no source code exists, 0 is returned.
See external documentation.
getShaderInfoLog(Shader, BufSize) -> string()
Types:
Shader = integer()
BufSize = integer()
Returns the information log for a shader object
gl:getShaderInfoLog returns the information log for the specified shader object.
The information log for a shader object is modified when the shader is compiled.
The string that is returned will be null terminated.
gl:getShaderInfoLog returns in InfoLog as much of the information log as it can, up
to a maximum of MaxLength characters. The number of characters actually returned,
excluding the null termination character, is specified by Length . If the length of
the returned string is not required, a value of ?NULL can be passed in the Length
argument. The size of the buffer required to store the returned information log can
be obtained by calling gl:getShaderiv/2 with the value ?GL_INFO_LOG_LENGTH .
The information log for a shader object is a string that may contain diagnostic
messages, warning messages, and other information about the last compile operation.
When a shader object is created, its information log will be a string of length 0.
See external documentation.
getShaderSource(Shader, BufSize) -> string()
Types:
Shader = integer()
BufSize = integer()
Returns the source code string from a shader object
gl:getShaderSource returns the concatenation of the source code strings from the
shader object specified by Shader . The source code strings for a shader object are
the result of a previous call to gl:shaderSource/2 . The string returned by the
function will be null terminated.
gl:getShaderSource returns in Source as much of the source code string as it can,
up to a maximum of BufSize characters. The number of characters actually returned,
excluding the null termination character, is specified by Length . If the length of
the returned string is not required, a value of ?NULL can be passed in the Length
argument. The size of the buffer required to store the returned source code string
can be obtained by calling gl:getShaderiv/2 with the value ?GL_SHADER_SOURCE_LENGTH
.
See external documentation.
getUniformLocation(Program, Name) -> integer()
Types:
Program = integer()
Name = string()
Returns the location of a uniform variable
gl:getUniformLocation returns an integer that represents the location of a specific
uniform variable within a program object. Name must be a null terminated string
that contains no white space. Name must be an active uniform variable name in
Program that is not a structure, an array of structures, or a subcomponent of a
vector or a matrix. This function returns -1 if Name does not correspond to an
active uniform variable in Program , if Name starts with the reserved prefix "gl_",
or if Name is associated with an atomic counter or a named uniform block.
Uniform variables that are structures or arrays of structures may be queried by
calling gl:getUniformLocation for each field within the structure. The array
element operator "[]" and the structure field operator "." may be used in Name in
order to select elements within an array or fields within a structure. The result
of using these operators is not allowed to be another structure, an array of
structures, or a subcomponent of a vector or a matrix. Except if the last part of
Name indicates a uniform variable array, the location of the first element of an
array can be retrieved by using the name of the array, or by using the name
appended by "[0]".
The actual locations assigned to uniform variables are not known until the program
object is linked successfully. After linking has occurred, the command
gl:getUniformLocation can be used to obtain the location of a uniform variable.
This location value can then be passed to gl:uniform1f/2 to set the value of the
uniform variable or to gl:getUniformfv/2 in order to query the current value of the
uniform variable. After a program object has been linked successfully, the index
values for uniform variables remain fixed until the next link command occurs.
Uniform variable locations and values can only be queried after a link if the link
was successful.
See external documentation.
getUniformfv(Program, Location) -> matrix()
Types:
Program = integer()
Location = integer()
Returns the value of a uniform variable
gl:getUniform returns in Params the value(s) of the specified uniform variable. The
type of the uniform variable specified by Location determines the number of values
returned. If the uniform variable is defined in the shader as a boolean, int, or
float, a single value will be returned. If it is defined as a vec2, ivec2, or
bvec2, two values will be returned. If it is defined as a vec3, ivec3, or bvec3,
three values will be returned, and so on. To query values stored in uniform
variables declared as arrays, call gl:getUniform for each element of the array. To
query values stored in uniform variables declared as structures, call gl:getUniform
for each field in the structure. The values for uniform variables declared as a
matrix will be returned in column major order.
The locations assigned to uniform variables are not known until the program object
is linked. After linking has occurred, the command gl:getUniformLocation/2 can be
used to obtain the location of a uniform variable. This location value can then be
passed to gl:getUniform in order to query the current value of the uniform
variable. After a program object has been linked successfully, the index values for
uniform variables remain fixed until the next link command occurs. The uniform
variable values can only be queried after a link if the link was successful.
See external documentation.
getUniformiv(Program, Location) -> {integer(), integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer(), integer(), integer(), integer(), integer(),
integer(), integer(), integer()}
Types:
Program = integer()
Location = integer()
See getUniformfv/2
getVertexAttribdv(Index, Pname) -> {float(), float(), float(), float()}
Types:
Index = integer()
Pname = enum()
Return a generic vertex attribute parameter
gl:getVertexAttrib returns in Params the value of a generic vertex attribute
parameter. The generic vertex attribute to be queried is specified by Index , and
the parameter to be queried is specified by Pname .
The accepted parameter names are as follows:
?GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING: Params returns a single value, the name of
the buffer object currently bound to the binding point corresponding to generic
vertex attribute array Index . If no buffer object is bound, 0 is returned. The
initial value is 0.
?GL_VERTEX_ATTRIB_ARRAY_ENABLED: Params returns a single value that is non-zero
(true) if the vertex attribute array for Index is enabled and 0 (false) if it is
disabled. The initial value is ?GL_FALSE.
?GL_VERTEX_ATTRIB_ARRAY_SIZE: Params returns a single value, the size of the vertex
attribute array for Index . The size is the number of values for each element of
the vertex attribute array, and it will be 1, 2, 3, or 4. The initial value is 4.
?GL_VERTEX_ATTRIB_ARRAY_STRIDE: Params returns a single value, the array stride for
(number of bytes between successive elements in) the vertex attribute array for
Index . A value of 0 indicates that the array elements are stored sequentially in
memory. The initial value is 0.
?GL_VERTEX_ATTRIB_ARRAY_TYPE: Params returns a single value, a symbolic constant
indicating the array type for the vertex attribute array for Index . Possible
values are ?GL_BYTE, ?GL_UNSIGNED_BYTE, ?GL_SHORT, ?GL_UNSIGNED_SHORT , ?GL_INT,
?GL_UNSIGNED_INT, ?GL_FLOAT, and ?GL_DOUBLE. The initial value is ?GL_FLOAT.
?GL_VERTEX_ATTRIB_ARRAY_NORMALIZED: Params returns a single value that is non-zero
(true) if fixed-point data types for the vertex attribute array indicated by Index
are normalized when they are converted to floating point, and 0 (false) otherwise.
The initial value is ?GL_FALSE.
?GL_VERTEX_ATTRIB_ARRAY_INTEGER: Params returns a single value that is non-zero
(true) if fixed-point data types for the vertex attribute array indicated by Index
have integer data types, and 0 (false) otherwise. The initial value is 0
(?GL_FALSE).
?GL_VERTEX_ATTRIB_ARRAY_DIVISOR: Params returns a single value that is the
frequency divisor used for instanced rendering. See gl:vertexAttribDivisor/2 . The
initial value is 0.
?GL_CURRENT_VERTEX_ATTRIB: Params returns four values that represent the current
value for the generic vertex attribute specified by index. Generic vertex attribute
0 is unique in that it has no current state, so an error will be generated if Index
is 0. The initial value for all other generic vertex attributes is (0,0,0,1).
gl:getVertexAttribdv and gl:getVertexAttribfv return the current attribute values
as four single-precision floating-point values; gl:getVertexAttribiv reads them as
floating-point values and converts them to four integer values;
gl:getVertexAttribIiv and gl:getVertexAttribIuiv read and return them as signed or
unsigned integer values, respectively; gl:getVertexAttribLdv reads and returns them
as four double-precision floating-point values.
All of the parameters except ?GL_CURRENT_VERTEX_ATTRIB represent state stored in
the currently bound vertex array object.
See external documentation.
getVertexAttribfv(Index, Pname) -> {float(), float(), float(), float()}
Types:
Index = integer()
Pname = enum()
See getVertexAttribdv/2
getVertexAttribiv(Index, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Index = integer()
Pname = enum()
See getVertexAttribdv/2
isProgram(Program) -> 0 | 1
Types:
Program = integer()
Determines if a name corresponds to a program object
gl:isProgram returns ?GL_TRUE if Program is the name of a program object previously
created with gl:createProgram/0 and not yet deleted with gl:deleteProgram/1 . If
Program is zero or a non-zero value that is not the name of a program object, or if
an error occurs, gl:isProgram returns ?GL_FALSE.
See external documentation.
isShader(Shader) -> 0 | 1
Types:
Shader = integer()
Determines if a name corresponds to a shader object
gl:isShader returns ?GL_TRUE if Shader is the name of a shader object previously
created with gl:createShader/1 and not yet deleted with gl:deleteShader/1 . If
Shader is zero or a non-zero value that is not the name of a shader object, or if
an error occurs, gl:isShader returns ?GL_FALSE.
See external documentation.
linkProgram(Program) -> ok
Types:
Program = integer()
Links a program object
gl:linkProgram links the program object specified by Program . If any shader
objects of type ?GL_VERTEX_SHADER are attached to Program , they will be used to
create an executable that will run on the programmable vertex processor. If any
shader objects of type ?GL_GEOMETRY_SHADER are attached to Program , they will be
used to create an executable that will run on the programmable geometry processor.
If any shader objects of type ?GL_FRAGMENT_SHADER are attached to Program , they
will be used to create an executable that will run on the programmable fragment
processor.
The status of the link operation will be stored as part of the program object's
state. This value will be set to ?GL_TRUE if the program object was linked without
errors and is ready for use, and ?GL_FALSE otherwise. It can be queried by calling
gl:getProgramiv/2 with arguments Program and ?GL_LINK_STATUS.
As a result of a successful link operation, all active user-defined uniform
variables belonging to Program will be initialized to 0, and each of the program
object's active uniform variables will be assigned a location that can be queried
by calling gl:getUniformLocation/2 . Also, any active user-defined attribute
variables that have not been bound to a generic vertex attribute index will be
bound to one at this time.
Linking of a program object can fail for a number of reasons as specified in the
OpenGL Shading Language Specification . The following lists some of the conditions
that will cause a link error.
The number of active attribute variables supported by the implementation has been
exceeded.
The storage limit for uniform variables has been exceeded.
The number of active uniform variables supported by the implementation has been
exceeded.
The main function is missing for the vertex, geometry or fragment shader.
A varying variable actually used in the fragment shader is not declared in the same
way (or is not declared at all) in the vertex shader, or geometry shader shader if
present.
A reference to a function or variable name is unresolved.
A shared global is declared with two different types or two different initial
values.
One or more of the attached shader objects has not been successfully compiled.
Binding a generic attribute matrix caused some rows of the matrix to fall outside
the allowed maximum of ?GL_MAX_VERTEX_ATTRIBS.
Not enough contiguous vertex attribute slots could be found to bind attribute
matrices.
The program object contains objects to form a fragment shader but does not contain
objects to form a vertex shader.
The program object contains objects to form a geometry shader but does not contain
objects to form a vertex shader.
The program object contains objects to form a geometry shader and the input
primitive type, output primitive type, or maximum output vertex count is not
specified in any compiled geometry shader object.
The program object contains objects to form a geometry shader and the input
primitive type, output primitive type, or maximum output vertex count is specified
differently in multiple geometry shader objects.
The number of active outputs in the fragment shader is greater than the value of
?GL_MAX_DRAW_BUFFERS .
The program has an active output assigned to a location greater than or equal to
the value of ?GL_MAX_DUAL_SOURCE_DRAW_BUFFERS and has an active output assigned an
index greater than or equal to one.
More than one varying out variable is bound to the same number and index.
The explicit binding assigments do not leave enough space for the linker to
automatically assign a location for a varying out array, which requires multiple
contiguous locations.
The Count specified by gl:transformFeedbackVaryings/3 is non-zero, but the program
object has no vertex or geometry shader.
Any variable name specified to gl:transformFeedbackVaryings/3 in the Varyings array
is not declared as an output in the vertex shader (or the geometry shader, if
active).
Any two entries in the Varyings array given gl:transformFeedbackVaryings/3 specify
the same varying variable.
The total number of components to capture in any transform feedback varying
variable is greater than the constant
?GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS and the buffer mode is
?SEPARATE_ATTRIBS.
When a program object has been successfully linked, the program object can be made
part of current state by calling gl:useProgram/1 . Whether or not the link
operation was successful, the program object's information log will be overwritten.
The information log can be retrieved by calling gl:getProgramInfoLog/2 .
gl:linkProgram will also install the generated executables as part of the current
rendering state if the link operation was successful and the specified program
object is already currently in use as a result of a previous call to
gl:useProgram/1 . If the program object currently in use is relinked
unsuccessfully, its link status will be set to ?GL_FALSE , but the executables and
associated state will remain part of the current state until a subsequent call to
gl:useProgram removes it from use. After it is removed from use, it cannot be made
part of current state until it has been successfully relinked.
If Program contains shader objects of type ?GL_VERTEX_SHADER, and optionally of
type ?GL_GEOMETRY_SHADER, but does not contain shader objects of type
?GL_FRAGMENT_SHADER , the vertex shader executable will be installed on the
programmable vertex processor, the geometry shader executable, if present, will be
installed on the programmable geometry processor, but no executable will be
installed on the fragment processor. The results of rasterizing primitives with
such a program will be undefined.
The program object's information log is updated and the program is generated at the
time of the link operation. After the link operation, applications are free to
modify attached shader objects, compile attached shader objects, detach shader
objects, delete shader objects, and attach additional shader objects. None of these
operations affects the information log or the program that is part of the program
object.
See external documentation.
shaderSource(Shader, String) -> ok
Types:
Shader = integer()
String = [string()]
Replaces the source code in a shader object
gl:shaderSource sets the source code in Shader to the source code in the array of
strings specified by String . Any source code previously stored in the shader
object is completely replaced. The number of strings in the array is specified by
Count . If Length is ?NULL, each string is assumed to be null terminated. If Length
is a value other than ?NULL, it points to an array containing a string length for
each of the corresponding elements of String . Each element in the Length array may
contain the length of the corresponding string (the null character is not counted
as part of the string length) or a value less than 0 to indicate that the string is
null terminated. The source code strings are not scanned or parsed at this time;
they are simply copied into the specified shader object.
See external documentation.
useProgram(Program) -> ok
Types:
Program = integer()
Installs a program object as part of current rendering state
gl:useProgram installs the program object specified by Program as part of current
rendering state. One or more executables are created in a program object by
successfully attaching shader objects to it with gl:attachShader/2 , successfully
compiling the shader objects with gl:compileShader/1 , and successfully linking the
program object with gl:linkProgram/1 .
A program object will contain an executable that will run on the vertex processor
if it contains one or more shader objects of type ?GL_VERTEX_SHADER that have been
successfully compiled and linked. A program object will contain an executable that
will run on the geometry processor if it contains one or more shader objects of
type ?GL_GEOMETRY_SHADER that have been successfully compiled and linked.
Similarly, a program object will contain an executable that will run on the
fragment processor if it contains one or more shader objects of type
?GL_FRAGMENT_SHADER that have been successfully compiled and linked.
While a program object is in use, applications are free to modify attached shader
objects, compile attached shader objects, attach additional shader objects, and
detach or delete shader objects. None of these operations will affect the
executables that are part of the current state. However, relinking the program
object that is currently in use will install the program object as part of the
current rendering state if the link operation was successful (see gl:linkProgram/1
). If the program object currently in use is relinked unsuccessfully, its link
status will be set to ?GL_FALSE, but the executables and associated state will
remain part of the current state until a subsequent call to gl:useProgram removes
it from use. After it is removed from use, it cannot be made part of current state
until it has been successfully relinked.
If Program is zero, then the current rendering state refers to an invalid program
object and the results of shader execution are undefined. However, this is not an
error.
If Program does not contain shader objects of type ?GL_FRAGMENT_SHADER, an
executable will be installed on the vertex, and possibly geometry processors, but
the results of fragment shader execution will be undefined.
See external documentation.
uniform1f(Location, V0) -> ok
Types:
Location = integer()
V0 = float()
Specify the value of a uniform variable for the current program object
gl:uniform modifies the value of a uniform variable or a uniform variable array.
The location of the uniform variable to be modified is specified by Location ,
which should be a value returned by gl:getUniformLocation/2 . gl:uniform operates
on the program object that was made part of current state by calling
gl:useProgram/1 .
The commands gl:uniform{1|2|3|4}{f|i|ui} are used to change the value of the
uniform variable specified by Location using the values passed as arguments. The
number specified in the command should match the number of components in the data
type of the specified uniform variable (e.g., 1 for float, int, unsigned int, bool;
2 for vec2, ivec2, uvec2, bvec2, etc.). The suffix f indicates that floating-point
values are being passed; the suffix i indicates that integer values are being
passed; the suffix ui indicates that unsigned integer values are being passed, and
this type should also match the data type of the specified uniform variable. The i
variants of this function should be used to provide values for uniform variables
defined as int, ivec2 , ivec3, ivec4, or arrays of these. The ui variants of this
function should be used to provide values for uniform variables defined as unsigned
int, uvec2, uvec3, uvec4, or arrays of these. The f variants should be used to
provide values for uniform variables of type float, vec2, vec3, vec4, or arrays of
these. Either the i, ui or f variants may be used to provide values for uniform
variables of type bool, bvec2 , bvec3, bvec4, or arrays of these. The uniform
variable will be set to false if the input value is 0 or 0.0f, and it will be set
to true otherwise.
All active uniform variables defined in a program object are initialized to 0 when
the program object is linked successfully. They retain the values assigned to them
by a call to gl:uniform until the next successful link operation occurs on the
program object, when they are once again initialized to 0.
The commands gl:uniform{1|2|3|4}{f|i|ui}v can be used to modify a single uniform
variable or a uniform variable array. These commands pass a count and a pointer to
the values to be loaded into a uniform variable or a uniform variable array. A
count of 1 should be used if modifying the value of a single uniform variable, and
a count of 1 or greater can be used to modify an entire array or part of an array.
When loading n elements starting at an arbitrary position m in a uniform variable
array, elements m + n - 1 in the array will be replaced with the new values. If M +
N - 1 is larger than the size of the uniform variable array, values for all array
elements beyond the end of the array will be ignored. The number specified in the
name of the command indicates the number of components for each element in Value ,
and it should match the number of components in the data type of the specified
uniform variable (e.g., 1 for float, int, bool; 2 for vec2, ivec2, bvec2, etc.).
The data type specified in the name of the command must match the data type for the
specified uniform variable as described previously for gl:uniform{1|2|3|4}{f|i|ui}.
For uniform variable arrays, each element of the array is considered to be of the
type indicated in the name of the command (e.g., gl:uniform3f or gl:uniform3fv can
be used to load a uniform variable array of type vec3). The number of elements of
the uniform variable array to be modified is specified by Count
The commands gl:uniformMatrix{2|3|4|2x3|3x2|2x4|4x2|3x4|4x3}fv are used to modify a
matrix or an array of matrices. The numbers in the command name are interpreted as
the dimensionality of the matrix. The number 2 indicates a 2 × 2 matrix (i.e., 4
values), the number 3 indicates a 3 × 3 matrix (i.e., 9 values), and the number 4
indicates a 4 × 4 matrix (i.e., 16 values). Non-square matrix dimensionality is
explicit, with the first number representing the number of columns and the second
number representing the number of rows. For example, 2x4 indicates a 2 × 4 matrix
with 2 columns and 4 rows (i.e., 8 values). If Transpose is ?GL_FALSE, each matrix
is assumed to be supplied in column major order. If Transpose is ?GL_TRUE, each
matrix is assumed to be supplied in row major order. The Count argument indicates
the number of matrices to be passed. A count of 1 should be used if modifying the
value of a single matrix, and a count greater than 1 can be used to modify an array
of matrices.
See external documentation.
uniform2f(Location, V0, V1) -> ok
Types:
Location = integer()
V0 = float()
V1 = float()
See uniform1f/2
uniform3f(Location, V0, V1, V2) -> ok
Types:
Location = integer()
V0 = float()
V1 = float()
V2 = float()
See uniform1f/2
uniform4f(Location, V0, V1, V2, V3) -> ok
Types:
Location = integer()
V0 = float()
V1 = float()
V2 = float()
V3 = float()
See uniform1f/2
uniform1i(Location, V0) -> ok
Types:
Location = integer()
V0 = integer()
See uniform1f/2
uniform2i(Location, V0, V1) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
See uniform1f/2
uniform3i(Location, V0, V1, V2) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
See uniform1f/2
uniform4i(Location, V0, V1, V2, V3) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
V3 = integer()
See uniform1f/2
uniform1fv(Location, Value) -> ok
Types:
Location = integer()
Value = [float()]
See uniform1f/2
uniform2fv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float()}]
See uniform1f/2
uniform3fv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float(), float()}]
See uniform1f/2
uniform4fv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float(), float(), float()}]
See uniform1f/2
uniform1iv(Location, Value) -> ok
Types:
Location = integer()
Value = [integer()]
See uniform1f/2
uniform2iv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer()}]
See uniform1f/2
uniform3iv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer(), integer()}]
See uniform1f/2
uniform4iv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer(), integer(), integer()}]
See uniform1f/2
uniformMatrix2fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix3fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float()}]
See uniform1f/2
uniformMatrix4fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
validateProgram(Program) -> ok
Types:
Program = integer()
Validates a program object
gl:validateProgram checks to see whether the executables contained in Program can
execute given the current OpenGL state. The information generated by the validation
process will be stored in Program 's information log. The validation information
may consist of an empty string, or it may be a string containing information about
how the current program object interacts with the rest of current OpenGL state.
This provides a way for OpenGL implementers to convey more information about why
the current program is inefficient, suboptimal, failing to execute, and so on.
The status of the validation operation will be stored as part of the program
object's state. This value will be set to ?GL_TRUE if the validation succeeded, and
?GL_FALSE otherwise. It can be queried by calling gl:getProgramiv/2 with arguments
Program and ?GL_VALIDATE_STATUS. If validation is successful, Program is guaranteed
to execute given the current state. Otherwise, Program is guaranteed to not
execute.
This function is typically useful only during application development. The
informational string stored in the information log is completely implementation
dependent; therefore, an application should not expect different OpenGL
implementations to produce identical information strings.
See external documentation.
vertexAttrib1d(Index, X) -> ok
Types:
Index = integer()
X = float()
Specifies the value of a generic vertex attribute
The gl:vertexAttrib family of entry points allows an application to pass generic
vertex attributes in numbered locations.
Generic attributes are defined as four-component values that are organized into an
array. The first entry of this array is numbered 0, and the size of the array is
specified by the implementation-dependent constant ?GL_MAX_VERTEX_ATTRIBS.
Individual elements of this array can be modified with a gl:vertexAttrib call that
specifies the index of the element to be modified and a value for that element.
These commands can be used to specify one, two, three, or all four components of
the generic vertex attribute specified by Index . A 1 in the name of the command
indicates that only one value is passed, and it will be used to modify the first
component of the generic vertex attribute. The second and third components will be
set to 0, and the fourth component will be set to 1. Similarly, a 2 in the name of
the command indicates that values are provided for the first two components, the
third component will be set to 0, and the fourth component will be set to 1. A 3 in
the name of the command indicates that values are provided for the first three
components and the fourth component will be set to 1, whereas a 4 in the name
indicates that values are provided for all four components.
The letters s, f, i, d, ub, us, and ui indicate whether the arguments are of type
short, float, int, double, unsigned byte, unsigned short, or unsigned int. When v
is appended to the name, the commands can take a pointer to an array of such
values.
Additional capitalized letters can indicate further alterations to the default
behavior of the glVertexAttrib function:
The commands containing N indicate that the arguments will be passed as fixed-point
values that are scaled to a normalized range according to the component conversion
rules defined by the OpenGL specification. Signed values are understood to
represent fixed-point values in the range [-1,1], and unsigned values are
understood to represent fixed-point values in the range [0,1].
The commands containing I indicate that the arguments are extended to full signed
or unsigned integers.
The commands containing P indicate that the arguments are stored as packed
components within a larger natural type.
The commands containing L indicate that the arguments are full 64-bit quantities
and should be passed directly to shader inputs declared as 64-bit double precision
types.
OpenGL Shading Language attribute variables are allowed to be of type mat2, mat3,
or mat4. Attributes of these types may be loaded using the gl:vertexAttrib entry
points. Matrices must be loaded into successive generic attribute slots in column
major order, with one column of the matrix in each generic attribute slot.
A user-defined attribute variable declared in a vertex shader can be bound to a
generic attribute index by calling gl:bindAttribLocation/3 . This allows an
application to use more descriptive variable names in a vertex shader. A subsequent
change to the specified generic vertex attribute will be immediately reflected as a
change to the corresponding attribute variable in the vertex shader.
The binding between a generic vertex attribute index and a user-defined attribute
variable in a vertex shader is part of the state of a program object, but the
current value of the generic vertex attribute is not. The value of each generic
vertex attribute is part of current state, just like standard vertex attributes,
and it is maintained even if a different program object is used.
An application may freely modify generic vertex attributes that are not bound to a
named vertex shader attribute variable. These values are simply maintained as part
of current state and will not be accessed by the vertex shader. If a generic vertex
attribute bound to an attribute variable in a vertex shader is not updated while
the vertex shader is executing, the vertex shader will repeatedly use the current
value for the generic vertex attribute.
See external documentation.
vertexAttrib1dv(Index::integer(), V) -> ok
Types:
V = {X::float()}
Equivalent to vertexAttrib1d(Index, X).
vertexAttrib1f(Index, X) -> ok
Types:
Index = integer()
X = float()
See vertexAttrib1d/2
vertexAttrib1fv(Index::integer(), V) -> ok
Types:
V = {X::float()}
Equivalent to vertexAttrib1f(Index, X).
vertexAttrib1s(Index, X) -> ok
Types:
Index = integer()
X = integer()
See vertexAttrib1d/2
vertexAttrib1sv(Index::integer(), V) -> ok
Types:
V = {X::integer()}
Equivalent to vertexAttrib1s(Index, X).
vertexAttrib2d(Index, X, Y) -> ok
Types:
Index = integer()
X = float()
Y = float()
See vertexAttrib1d/2
vertexAttrib2dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to vertexAttrib2d(Index, X, Y).
vertexAttrib2f(Index, X, Y) -> ok
Types:
Index = integer()
X = float()
Y = float()
See vertexAttrib1d/2
vertexAttrib2fv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to vertexAttrib2f(Index, X, Y).
vertexAttrib2s(Index, X, Y) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
See vertexAttrib1d/2
vertexAttrib2sv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to vertexAttrib2s(Index, X, Y).
vertexAttrib3d(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
See vertexAttrib1d/2
vertexAttrib3dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to vertexAttrib3d(Index, X, Y, Z).
vertexAttrib3f(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
See vertexAttrib1d/2
vertexAttrib3fv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to vertexAttrib3f(Index, X, Y, Z).
vertexAttrib3s(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
See vertexAttrib1d/2
vertexAttrib3sv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to vertexAttrib3s(Index, X, Y, Z).
vertexAttrib4Nbv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4Niv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4Nsv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4Nub(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertexAttrib1d/2
vertexAttrib4Nubv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertexAttrib4Nub(Index, X, Y, Z, W).
vertexAttrib4Nuiv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4Nusv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4bv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4d(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
See vertexAttrib1d/2
vertexAttrib4dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to vertexAttrib4d(Index, X, Y, Z, W).
vertexAttrib4f(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
See vertexAttrib1d/2
vertexAttrib4fv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to vertexAttrib4f(Index, X, Y, Z, W).
vertexAttrib4iv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4s(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertexAttrib1d/2
vertexAttrib4sv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertexAttrib4s(Index, X, Y, Z, W).
vertexAttrib4ubv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4uiv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttrib4usv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttribPointer(Index, Size, Type, Normalized, Stride, Pointer) -> ok
Types:
Index = integer()
Size = integer()
Type = enum()
Normalized = 0 | 1
Stride = integer()
Pointer = offset() | mem()
Define an array of generic vertex attribute data
gl:vertexAttribPointer, gl:vertexAttribIPointer and gl:vertexAttribLPointer specify
the location and data format of the array of generic vertex attributes at index
Index to use when rendering. Size specifies the number of components per attribute
and must be 1, 2, 3, 4, or ?GL_BGRA. Type specifies the data type of each
component, and Stride specifies the byte stride from one attribute to the next,
allowing vertices and attributes to be packed into a single array or stored in
separate arrays.
For gl:vertexAttribPointer, if Normalized is set to ?GL_TRUE, it indicates that
values stored in an integer format are to be mapped to the range [-1,1] (for signed
values) or [0,1] (for unsigned values) when they are accessed and converted to
floating point. Otherwise, values will be converted to floats directly without
normalization.
For gl:vertexAttribIPointer, only the integer types ?GL_BYTE, ?GL_UNSIGNED_BYTE ,
?GL_SHORT, ?GL_UNSIGNED_SHORT, ?GL_INT, ?GL_UNSIGNED_INT are accepted. Values are
always left as integer values.
gl:vertexAttribLPointer specifies state for a generic vertex attribute array
associated with a shader attribute variable declared with 64-bit double precision
components. Type must be ?GL_DOUBLE. Index , Size , and Stride behave as described
for gl:vertexAttribPointer and gl:vertexAttribIPointer.
If Pointer is not NULL, a non-zero named buffer object must be bound to the
?GL_ARRAY_BUFFER target (see gl:bindBuffer/2 ), otherwise an error is generated.
Pointer is treated as a byte offset into the buffer object's data store. The buffer
object binding (?GL_ARRAY_BUFFER_BINDING) is saved as generic vertex attribute
array state (?GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING ) for index Index .
When a generic vertex attribute array is specified, Size , Type , Normalized ,
Stride , and Pointer are saved as vertex array state, in addition to the current
vertex array buffer object binding.
To enable and disable a generic vertex attribute array, call
gl:disableVertexAttribArray/1 and gl:disableVertexAttribArray/1 with Index . If
enabled, the generic vertex attribute array is used when gl:drawArrays/3 ,
gl:multiDrawArrays/3 , gl:drawElements/4 , see glMultiDrawElements, or
gl:drawRangeElements/6 is called.
See external documentation.
uniformMatrix2x3fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix3x2fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix2x4fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
uniformMatrix4x2fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
uniformMatrix3x4fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix4x3fv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See uniform1f/2
colorMaski(Index, R, G, B, A) -> ok
Types:
Index = integer()
R = 0 | 1
G = 0 | 1
B = 0 | 1
A = 0 | 1
glColorMaski
See external documentation.
getBooleani_v(Target, Index) -> [0 | 1]
Types:
Target = enum()
Index = integer()
See getBooleanv/1
getIntegeri_v(Target, Index) -> [integer()]
Types:
Target = enum()
Index = integer()
See getBooleanv/1
enablei(Target, Index) -> ok
Types:
Target = enum()
Index = integer()
See enable/1
disablei(Target, Index) -> ok
Types:
Target = enum()
Index = integer()
glEnablei
See external documentation.
isEnabledi(Target, Index) -> 0 | 1
Types:
Target = enum()
Index = integer()
glIsEnabledi
See external documentation.
beginTransformFeedback(PrimitiveMode) -> ok
Types:
PrimitiveMode = enum()
Start transform feedback operation
Transform feedback mode captures the values of varying variables written by the
vertex shader (or, if active, the geometry shader). Transform feedback is said to
be active after a call to gl:beginTransformFeedback until a subsequent call to
gl:beginTransformFeedback/1 . Transform feedback commands must be paired.
If no geometry shader is present, while transform feedback is active the Mode
parameter to gl:drawArrays/3 must match those specified in the following
table:Transform FeedbackPrimitiveModeAllowed Render PrimitiveModes
?GL_POINTS?GL_POINTS
?GL_LINES?GL_LINES, ?GL_LINE_LOOP, ?GL_LINE_STRIP , ?GL_LINES_ADJACENCY,
?GL_LINE_STRIP_ADJACENCY
?GL_TRIANGLES?GL_TRIANGLES, ?GL_TRIANGLE_STRIP, ?GL_TRIANGLE_FAN,
?GL_TRIANGLES_ADJACENCY , ?GL_TRIANGLE_STRIP_ADJACENCY
If a geometry shader is present, the output primitive type from the geometry shader
must match those provided in the following table:Transform
FeedbackPrimitiveModeAllowed Geometry Shader Output Primitive Type
?GL_POINTS?points
?GL_LINES?line_strip
?GL_TRIANGLES?triangle_strip
See external documentation.
endTransformFeedback() -> ok
See beginTransformFeedback/1
bindBufferRange(Target, Index, Buffer, Offset, Size) -> ok
Types:
Target = enum()
Index = integer()
Buffer = integer()
Offset = integer()
Size = integer()
Bind a range within a buffer object to an indexed buffer target
gl:bindBufferRange binds a range the buffer object Buffer represented by Offset and
Size to the binding point at index Index of the array of targets specified by
Target . Each Target represents an indexed array of buffer binding points, as well
as a single general binding point that can be used by other buffer manipulation
functions such as gl:bindBuffer/2 or see glMapBuffer. In addition to binding a
range of Buffer to the indexed buffer binding target, gl:bindBufferBase also binds
the range to the generic buffer binding point specified by Target .
Offset specifies the offset in basic machine units into the buffer object Buffer
and Size specifies the amount of data that can be read from the buffer object while
used as an indexed target.
See external documentation.
bindBufferBase(Target, Index, Buffer) -> ok
Types:
Target = enum()
Index = integer()
Buffer = integer()
Bind a buffer object to an indexed buffer target
gl:bindBufferBase binds the buffer object Buffer to the binding point at index
Index of the array of targets specified by Target . Each Target represents an
indexed array of buffer binding points, as well as a single general binding point
that can be used by other buffer manipulation functions such as gl:bindBuffer/2 or
see glMapBuffer. In addition to binding Buffer to the indexed buffer binding
target, gl:bindBufferBase also binds Buffer to the generic buffer binding point
specified by Target .
See external documentation.
transformFeedbackVaryings(Program, Varyings, BufferMode) -> ok
Types:
Program = integer()
Varyings = [string()]
BufferMode = enum()
Specify values to record in transform feedback buffers
The names of the vertex or geometry shader outputs to be recorded in transform
feedback mode are specified using gl:transformFeedbackVaryings. When a geometry
shader is active, transform feedback records the values of selected geometry shader
output variables from the emitted vertices. Otherwise, the values of the selected
vertex shader outputs are recorded.
The state set by gl:tranformFeedbackVaryings is stored and takes effect next time
gl:linkProgram/1 is called on Program . When gl:linkProgram/1 is called, Program is
linked so that the values of the specified varying variables for the vertices of
each primitive generated by the GL are written to a single buffer object if
BufferMode is ?GL_INTERLEAVED_ATTRIBS or multiple buffer objects if BufferMode is
?GL_SEPARATE_ATTRIBS .
In addition to the errors generated by gl:transformFeedbackVaryings, the program
Program will fail to link if:
The count specified by gl:transformFeedbackVaryings is non-zero, but the program
object has no vertex or geometry shader.
Any variable name specified in the Varyings array is not declared as an output in
the vertex shader (or the geometry shader, if active).
Any two entries in the Varyings array specify the same varying variable.
The total number of components to capture in any varying variable in Varyings is
greater than the constant ?GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS and the
buffer mode is ?GL_SEPARATE_ATTRIBS.
The total number of components to capture is greater than the constant
?GL_MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS and the buffer mode is
?GL_INTERLEAVED_ATTRIBS.
See external documentation.
getTransformFeedbackVarying(Program, Index, BufSize) -> {Size::integer(), Type::enum(),
Name::string()}
Types:
Program = integer()
Index = integer()
BufSize = integer()
Retrieve information about varying variables selected for transform feedback
Information about the set of varying variables in a linked program that will be
captured during transform feedback may be retrieved by calling
gl:getTransformFeedbackVarying. gl:getTransformFeedbackVarying provides information
about the varying variable selected by Index . An Index of 0 selects the first
varying variable specified in the Varyings array passed to
gl:transformFeedbackVaryings/3 , and an Index of ?GL_TRANSFORM_FEEDBACK_VARYINGS-1
selects the last such variable.
The name of the selected varying is returned as a null-terminated string in Name .
The actual number of characters written into Name , excluding the null terminator,
is returned in Length . If Length is NULL, no length is returned. The maximum
number of characters that may be written into Name , including the null terminator,
is specified by BufSize .
The length of the longest varying name in program is given by
?GL_TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH , which can be queried with
gl:getProgramiv/2 .
For the selected varying variable, its type is returned into Type . The size of the
varying is returned into Size . The value in Size is in units of the type returned
in Type . The type returned can be any of the scalar, vector, or matrix attribute
types returned by gl:getActiveAttrib/3 . If an error occurred, the return
parameters Length , Size , Type and Name will be unmodified. This command will
return as much information about the varying variables as possible. If no
information is available, Length will be set to zero and Name will be an empty
string. This situation could arise if gl:getTransformFeedbackVarying is called
after a failed link.
See external documentation.
clampColor(Target, Clamp) -> ok
Types:
Target = enum()
Clamp = enum()
specify whether data read via
gl:readPixels/7 should be clamped
gl:clampColor controls color clamping that is performed during gl:readPixels/7 .
Target must be ?GL_CLAMP_READ_COLOR. If Clamp is ?GL_TRUE, read color clamping is
enabled; if Clamp is ?GL_FALSE, read color clamping is disabled. If Clamp is
?GL_FIXED_ONLY, read color clamping is enabled only if the selected read buffer has
fixed point components and disabled otherwise.
See external documentation.
beginConditionalRender(Id, Mode) -> ok
Types:
Id = integer()
Mode = enum()
Start conditional rendering
Conditional rendering is started using gl:beginConditionalRender and ended using
gl:endConditionalRender . During conditional rendering, all vertex array commands,
as well as gl:clear/1 and gl:clearBufferiv/3 have no effect if the
(?GL_SAMPLES_PASSED) result of the query object Id is zero, or if the
(?GL_ANY_SAMPLES_PASSED) result is ?GL_FALSE . The results of commands setting the
current vertex state, such as gl:vertexAttrib1d/2 are undefined. If the
(?GL_SAMPLES_PASSED) result is non-zero or if the (?GL_ANY_SAMPLES_PASSED ) result
is ?GL_TRUE, such commands are not discarded. The Id parameter to
gl:beginConditionalRender must be the name of a query object previously returned
from a call to gl:genQueries/1 . Mode specifies how the results of the query object
are to be interpreted. If Mode is ?GL_QUERY_WAIT, the GL waits for the results of
the query to be available and then uses the results to determine if subsequent
rendering commands are discarded. If Mode is ?GL_QUERY_NO_WAIT, the GL may choose
to unconditionally execute the subsequent rendering commands without waiting for
the query to complete.
If Mode is ?GL_QUERY_BY_REGION_WAIT, the GL will also wait for occlusion query
results and discard rendering commands if the result of the occlusion query is
zero. If the query result is non-zero, subsequent rendering commands are executed,
but the GL may discard the results of the commands for any region of the
framebuffer that did not contribute to the sample count in the specified occlusion
query. Any such discarding is done in an implementation-dependent manner, but the
rendering command results may not be discarded for any samples that contributed to
the occlusion query sample count. If Mode is ?GL_QUERY_BY_REGION_NO_WAIT, the GL
operates as in ?GL_QUERY_BY_REGION_WAIT , but may choose to unconditionally execute
the subsequent rendering commands without waiting for the query to complete.
See external documentation.
endConditionalRender() -> ok
See beginConditionalRender/2
vertexAttribIPointer(Index, Size, Type, Stride, Pointer) -> ok
Types:
Index = integer()
Size = integer()
Type = enum()
Stride = integer()
Pointer = offset() | mem()
glVertexAttribIPointer
See external documentation.
getVertexAttribIiv(Index, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Index = integer()
Pname = enum()
See getVertexAttribdv/2
getVertexAttribIuiv(Index, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Index = integer()
Pname = enum()
glGetVertexAttribI
See external documentation.
vertexAttribI1i(Index, X) -> ok
Types:
Index = integer()
X = integer()
See vertexAttrib1d/2
vertexAttribI2i(Index, X, Y) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
See vertexAttrib1d/2
vertexAttribI3i(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
See vertexAttrib1d/2
vertexAttribI4i(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertexAttrib1d/2
vertexAttribI1ui(Index, X) -> ok
Types:
Index = integer()
X = integer()
See vertexAttrib1d/2
vertexAttribI2ui(Index, X, Y) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
See vertexAttrib1d/2
vertexAttribI3ui(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
See vertexAttrib1d/2
vertexAttribI4ui(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = integer()
Y = integer()
Z = integer()
W = integer()
See vertexAttrib1d/2
vertexAttribI1iv(Index::integer(), V) -> ok
Types:
V = {X::integer()}
Equivalent to vertexAttribI1i(Index, X).
vertexAttribI2iv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to vertexAttribI2i(Index, X, Y).
vertexAttribI3iv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to vertexAttribI3i(Index, X, Y, Z).
vertexAttribI4iv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertexAttribI4i(Index, X, Y, Z, W).
vertexAttribI1uiv(Index::integer(), V) -> ok
Types:
V = {X::integer()}
Equivalent to vertexAttribI1ui(Index, X).
vertexAttribI2uiv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer()}
Equivalent to vertexAttribI2ui(Index, X, Y).
vertexAttribI3uiv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer()}
Equivalent to vertexAttribI3ui(Index, X, Y, Z).
vertexAttribI4uiv(Index::integer(), V) -> ok
Types:
V = {X::integer(), Y::integer(), Z::integer(), W::integer()}
Equivalent to vertexAttribI4ui(Index, X, Y, Z, W).
vertexAttribI4bv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttribI4sv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttribI4ubv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
vertexAttribI4usv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
See vertexAttrib1d/2
getUniformuiv(Program, Location) -> {integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer(), integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer()}
Types:
Program = integer()
Location = integer()
See getUniformfv/2
bindFragDataLocation(Program, Color, Name) -> ok
Types:
Program = integer()
Color = integer()
Name = string()
Bind a user-defined varying out variable to a fragment shader color number
gl:bindFragDataLocation explicitly specifies the binding of the user-defined
varying out variable Name to fragment shader color number ColorNumber for program
Program . If Name was bound previously, its assigned binding is replaced with
ColorNumber . Name must be a null-terminated string. ColorNumber must be less than
?GL_MAX_DRAW_BUFFERS .
The bindings specified by gl:bindFragDataLocation have no effect until Program is
next linked. Bindings may be specified at any time after Program has been created.
Specifically, they may be specified before shader objects are attached to the
program. Therefore, any name may be specified in Name , including a name that is
never used as a varying out variable in any fragment shader object. Names beginning
with ?gl_ are reserved by the GL.
In addition to the errors generated by gl:bindFragDataLocation, the program Program
will fail to link if:
The number of active outputs is greater than the value ?GL_MAX_DRAW_BUFFERS.
More than one varying out variable is bound to the same color number.
See external documentation.
getFragDataLocation(Program, Name) -> integer()
Types:
Program = integer()
Name = string()
Query the bindings of color numbers to user-defined varying out variables
gl:getFragDataLocation retrieves the assigned color number binding for the user-
defined varying out variable Name for program Program . Program must have
previously been linked. Name must be a null-terminated string. If Name is not the
name of an active user-defined varying out fragment shader variable within Program
, -1 will be returned.
See external documentation.
uniform1ui(Location, V0) -> ok
Types:
Location = integer()
V0 = integer()
See uniform1f/2
uniform2ui(Location, V0, V1) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
See uniform1f/2
uniform3ui(Location, V0, V1, V2) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
See uniform1f/2
uniform4ui(Location, V0, V1, V2, V3) -> ok
Types:
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
V3 = integer()
See uniform1f/2
uniform1uiv(Location, Value) -> ok
Types:
Location = integer()
Value = [integer()]
See uniform1f/2
uniform2uiv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer()}]
See uniform1f/2
uniform3uiv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer(), integer()}]
See uniform1f/2
uniform4uiv(Location, Value) -> ok
Types:
Location = integer()
Value = [{integer(), integer(), integer(), integer()}]
See uniform1f/2
texParameterIiv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer()}
See texParameterf/3
texParameterIuiv(Target, Pname, Params) -> ok
Types:
Target = enum()
Pname = enum()
Params = {integer()}
glTexParameterI
See external documentation.
getTexParameterIiv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
See getTexParameterfv/2
getTexParameterIuiv(Target, Pname) -> {integer(), integer(), integer(), integer()}
Types:
Target = enum()
Pname = enum()
glGetTexParameterI
See external documentation.
clearBufferiv(Buffer, Drawbuffer, Value) -> ok
Types:
Buffer = enum()
Drawbuffer = integer()
Value = {integer()}
Clear individual buffers of the currently bound draw framebuffer
gl:clearBuffer* clears the specified buffer to the specified value(s). If Buffer is
?GL_COLOR, a particular draw buffer ?GL_DRAWBUFFER I is specified by passing I as
DrawBuffer . In this case, Value points to a four-element vector specifying the R,
G, B and A color to clear that draw buffer to. If Buffer is one of ?GL_FRONT,
?GL_BACK, ?GL_LEFT, ?GL_RIGHT, or ?GL_FRONT_AND_BACK , identifying multiple
buffers, each selected buffer is cleared to the same value. Clamping and conversion
for fixed-point color buffers are performed in the same fashion as gl:clearColor/4
.
If Buffer is ?GL_DEPTH, DrawBuffer must be zero, and Value points to a single value
to clear the depth buffer to. Only gl:clearBufferfv should be used to clear depth
buffers. Clamping and conversion for fixed-point depth buffers are performed in the
same fashion as gl:clearDepth/1 .
If Buffer is ?GL_STENCIL, DrawBuffer must be zero, and Value points to a single
value to clear the stencil buffer to. Only gl:clearBufferiv should be used to clear
stencil buffers. Masing and type conversion are performed in the same fashion as
gl:clearStencil/1 .
gl:clearBufferfi may be used to clear the depth and stencil buffers. Buffer must be
?GL_DEPTH_STENCIL and DrawBuffer must be zero. Depth and Stencil are the depth and
stencil values, respectively.
The result of gl:clearBuffer is undefined if no conversion between the type of
Value and the buffer being cleared is defined. However, this is not an error.
See external documentation.
clearBufferuiv(Buffer, Drawbuffer, Value) -> ok
Types:
Buffer = enum()
Drawbuffer = integer()
Value = {integer()}
See clearBufferiv/3
clearBufferfv(Buffer, Drawbuffer, Value) -> ok
Types:
Buffer = enum()
Drawbuffer = integer()
Value = {float()}
See clearBufferiv/3
clearBufferfi(Buffer, Drawbuffer, Depth, Stencil) -> ok
Types:
Buffer = enum()
Drawbuffer = integer()
Depth = float()
Stencil = integer()
glClearBufferfi
See external documentation.
getStringi(Name, Index) -> string()
Types:
Name = enum()
Index = integer()
See getString/1
drawArraysInstanced(Mode, First, Count, Primcount) -> ok
Types:
Mode = enum()
First = integer()
Count = integer()
Primcount = integer()
glDrawArraysInstance
See external documentation.
drawElementsInstanced(Mode, Count, Type, Indices, Primcount) -> ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Primcount = integer()
glDrawElementsInstance
See external documentation.
texBuffer(Target, Internalformat, Buffer) -> ok
Types:
Target = enum()
Internalformat = enum()
Buffer = integer()
Attach the storage for a buffer object to the active buffer texture
gl:texBuffer attaches the storage for the buffer object named Buffer to the active
buffer texture, and specifies the internal format for the texel array found in the
attached buffer object. If Buffer is zero, any buffer object attached to the buffer
texture is detached and no new buffer object is attached. If Buffer is non-zero, it
must be the name of an existing buffer object. Target must be ?GL_TEXTURE_BUFFER .
Internalformat specifies the storage format, and must be one of the following sized
internal formats:Component
Sized Internal FormatBase TypeComponentsNorm0123
?GL_R8ubyte1YESR00 1
?GL_R16ushort1YESR 001
?GL_R16Fhalf1NO R001
?GL_R32Ffloat 1NOR001
?GL_R8I byte1NOR001
?GL_R16I short1NOR001
?GL_R32Iint1NOR001
?GL_R8UIubyte1NOR0 01
?GL_R16UIushort1NO R001
?GL_R32UIuint1 NOR001
?GL_RG8ubyte 2YESRG01
?GL_RG16 ushort2YESRG01
?GL_RG16Fhalf2NORG0 1
?GL_RG32Ffloat2NORG 01
?GL_RG8Ibyte2NO RG01
?GL_RG16Ishort 2NORG01
?GL_RG32I int2NORG01
?GL_RG8UI ubyte2NORG01
?GL_RG16UIushort2NORG0 1
?GL_RG32UIuint2NORG 01
?GL_RGB32Ffloat3NO RGB1
?GL_RGB32Iint 3NORGB1
?GL_RGB32UI uint3NORGB1
?GL_RGBA8uint4YESRGB A
?GL_RGBA16short4YESR GBA
?GL_RGBA16Fhalf4NO RGBA
?GL_RGBA32Ffloat 4NORGBA
?GL_RGBA8I byte4NORGBA
?GL_RGBA16Ishort4NORGB A
?GL_RGBA32Iint4NORG BA
?GL_RGBA8UIubyte4NO RGBA
?GL_RGBA16UIushort 4NORGBA
?GL_RGBA32UI uint4NORGBA
When a buffer object is attached to a buffer texture, the buffer object's data
store is taken as the texture's texel array. The number of texels in the buffer
texture's texel array is given by buffer_size components×sizeof( base_type/)
where buffer_size is the size of the buffer object, in basic machine units and
components and base type are the element count and base data type for elements, as
specified in the table above. The number of texels in the texel array is then
clamped to the implementation-dependent limit ?GL_MAX_TEXTURE_BUFFER_SIZE. When a
buffer texture is accessed in a shader, the results of a texel fetch are undefined
if the specified texel coordinate is negative, or greater than or equal to the
clamped number of texels in the texel array.
See external documentation.
primitiveRestartIndex(Index) -> ok
Types:
Index = integer()
Specify the primitive restart index
gl:primitiveRestartIndex specifies a vertex array element that is treated specially
when primitive restarting is enabled. This is known as the primitive restart index.
When one of the Draw* commands transfers a set of generic attribute array elements
to the GL, if the index within the vertex arrays corresponding to that set is equal
to the primitive restart index, then the GL does not process those elements as a
vertex. Instead, it is as if the drawing command ended with the immediately
preceding transfer, and another drawing command is immediately started with the
same parameters, but only transferring the immediately following element through
the end of the originally specified elements.
When either gl:drawElementsBaseVertex/5 , gl:drawElementsInstancedBaseVertex/6 or
see glMultiDrawElementsBaseVertex is used, the primitive restart comparison occurs
before the basevertex offset is added to the array index.
See external documentation.
getInteger64i_v(Target, Index) -> [integer()]
Types:
Target = enum()
Index = integer()
See getBooleanv/1
getBufferParameteri64v(Target, Pname) -> [integer()]
Types:
Target = enum()
Pname = enum()
glGetBufferParameteri64v
See external documentation.
framebufferTexture(Target, Attachment, Texture, Level) -> ok
Types:
Target = enum()
Attachment = enum()
Texture = integer()
Level = integer()
Attach a level of a texture object as a logical buffer to the currently bound
framebuffer object
gl:framebufferTexture, gl:framebufferTexture1D, gl:framebufferTexture2D, and
gl:framebufferTexture attach a selected mipmap level or image of a texture object
as one of the logical buffers of the framebuffer object currently bound to Target .
Target must be ?GL_DRAW_FRAMEBUFFER, ?GL_READ_FRAMEBUFFER, or ?GL_FRAMEBUFFER .
?GL_FRAMEBUFFER is equivalent to ?GL_DRAW_FRAMEBUFFER.
Attachment specifies the logical attachment of the framebuffer and must be
?GL_COLOR_ATTACHMENT i, ?GL_DEPTH_ATTACHMENT, ?GL_STENCIL_ATTACHMENT or
?GL_DEPTH_STENCIL_ATTACHMMENT . i in ?GL_COLOR_ATTACHMENTi may range from zero to
the value of ?GL_MAX_COLOR_ATTACHMENTS - 1. Attaching a level of a texture to
?GL_DEPTH_STENCIL_ATTACHMENT is equivalent to attaching that level to both the
?GL_DEPTH_ATTACHMENTand the ?GL_STENCIL_ATTACHMENT attachment points
simultaneously.
Textarget specifies what type of texture is named by Texture , and for cube map
textures, specifies the face that is to be attached. If Texture is not zero, it
must be the name of an existing texture with type Textarget , unless it is a cube
map texture, in which case Textarget must be ?GL_TEXTURE_CUBE_MAP_POSITIVE_X
?GL_TEXTURE_CUBE_MAP_NEGATIVE_X, ?GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Y , ?GL_TEXTURE_CUBE_MAP_POSITIVE_Z, or
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Z.
If Texture is non-zero, the specified Level of the texture object named Texture is
attached to the framebfufer attachment point named by Attachment . For
gl:framebufferTexture1D , gl:framebufferTexture2D, and gl:framebufferTexture3D,
Texture must be zero or the name of an existing texture with a target of Textarget
, or Texture must be the name of an existing cube-map texture and Textarget must be
one of ?GL_TEXTURE_CUBE_MAP_POSITIVE_X , ?GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
?GL_TEXTURE_CUBE_MAP_POSITIVE_Z, ?GL_TEXTURE_CUBE_MAP_NEGATIVE_X ,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, or ?GL_TEXTURE_CUBE_MAP_NEGATIVE_Z.
If Textarget is ?GL_TEXTURE_RECTANGLE, ?GL_TEXTURE_2D_MULTISAMPLE, or
?GL_TEXTURE_2D_MULTISAMPLE_ARRAY, then Level must be zero. If Textarget is
?GL_TEXTURE_3D, then level must be greater than or equal to zero and less than or
equal to log2 of the value of ?GL_MAX_3D_TEXTURE_SIZE. If Textarget is one of
?GL_TEXTURE_CUBE_MAP_POSITIVE_X, ?GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
?GL_TEXTURE_CUBE_MAP_POSITIVE_Z , ?GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, or ?GL_TEXTURE_CUBE_MAP_NEGATIVE_Z , then Level
must be greater than or equal to zero and less than or equal to log2 of the value
of ?GL_MAX_CUBE_MAP_TEXTURE_SIZE. For all other values of Textarget , Level must be
greater than or equal to zero and no larger than log2 of the value of
?GL_MAX_TEXTURE_SIZE.
Layer specifies the layer of a 2-dimensional image within a 3-dimensional texture.
For gl:framebufferTexture1D, if Texture is not zero, then Textarget must be
?GL_TEXTURE_1D. For gl:framebufferTexture2D, if Texture is not zero, Textarget must
be one of ?GL_TEXTURE_2D, ?GL_TEXTURE_RECTANGLE , ?GL_TEXTURE_CUBE_MAP_POSITIVE_X,
?GL_TEXTURE_CUBE_MAP_POSITIVE_Y, ?GL_TEXTURE_CUBE_MAP_POSITIVE_Z ,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_X, ?GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
?GL_TEXTURE_CUBE_MAP_NEGATIVE_Z , or ?GL_TEXTURE_2D_MULTISAMPLE. For
gl:framebufferTexture3D, if Texture is not zero, then Textarget must be
?GL_TEXTURE_3D.
See external documentation.
vertexAttribDivisor(Index, Divisor) -> ok
Types:
Index = integer()
Divisor = integer()
Modify the rate at which generic vertex attributes advance during instanced
rendering
gl:vertexAttribDivisor modifies the rate at which generic vertex attributes advance
when rendering multiple instances of primitives in a single draw call. If Divisor
is zero, the attribute at slot Index advances once per vertex. If Divisor is non-
zero, the attribute advances once per Divisor instances of the set(s) of vertices
being rendered. An attribute is referred to as instanced if its
?GL_VERTEX_ATTRIB_ARRAY_DIVISOR value is non-zero.
Index must be less than the value of ?GL_MAX_VERTEX_ATTRIBUTES.
See external documentation.
minSampleShading(Value) -> ok
Types:
Value = clamp()
Specifies minimum rate at which sample shaing takes place
gl:minSampleShading specifies the rate at which samples are shaded within a covered
pixel. Sample-rate shading is enabled by calling gl:enable/1 with the parameter
?GL_SAMPLE_SHADING . If ?GL_MULTISAMPLE or ?GL_SAMPLE_SHADING is disabled, sample
shading has no effect. Otherwise, an implementation must provide at least as many
unique color values for each covered fragment as specified by Value times Samples
where Samples is the value of ?GL_SAMPLES for the current framebuffer. At least 1
sample for each covered fragment is generated.
A Value of 1.0 indicates that each sample in the framebuffer should be indpendently
shaded. A Value of 0.0 effectively allows the GL to ignore sample rate shading. Any
value between 0.0 and 1.0 allows the GL to shade only a subset of the total samples
within each covered fragment. Which samples are shaded and the algorithm used to
select that subset of the fragment's samples is implementation dependent.
See external documentation.
blendEquationi(Buf, Mode) -> ok
Types:
Buf = integer()
Mode = enum()
See blendEquation/1
blendEquationSeparatei(Buf, ModeRGB, ModeAlpha) -> ok
Types:
Buf = integer()
ModeRGB = enum()
ModeAlpha = enum()
See blendEquationSeparate/2
blendFunci(Buf, Src, Dst) -> ok
Types:
Buf = integer()
Src = enum()
Dst = enum()
glBlendFunci
See external documentation.
blendFuncSeparatei(Buf, SrcRGB, DstRGB, SrcAlpha, DstAlpha) -> ok
Types:
Buf = integer()
SrcRGB = enum()
DstRGB = enum()
SrcAlpha = enum()
DstAlpha = enum()
See blendFuncSeparate/4
loadTransposeMatrixfARB(M) -> ok
Types:
M = matrix()
glLoadTransposeMatrixARB
See external documentation.
loadTransposeMatrixdARB(M) -> ok
Types:
M = matrix()
glLoadTransposeMatrixARB
See external documentation.
multTransposeMatrixfARB(M) -> ok
Types:
M = matrix()
glMultTransposeMatrixARB
See external documentation.
multTransposeMatrixdARB(M) -> ok
Types:
M = matrix()
glMultTransposeMatrixARB
See external documentation.
weightbvARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
weightsvARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
weightivARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
weightfvARB(Weights) -> ok
Types:
Weights = [float()]
glWeightARB
See external documentation.
weightdvARB(Weights) -> ok
Types:
Weights = [float()]
glWeightARB
See external documentation.
weightubvARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
weightusvARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
weightuivARB(Weights) -> ok
Types:
Weights = [integer()]
glWeightARB
See external documentation.
vertexBlendARB(Count) -> ok
Types:
Count = integer()
glVertexBlenARB
See external documentation.
currentPaletteMatrixARB(Index) -> ok
Types:
Index = integer()
glCurrentPaletteMatrixARB
See external documentation.
matrixIndexubvARB(Indices) -> ok
Types:
Indices = [integer()]
glMatrixIndexARB
See external documentation.
matrixIndexusvARB(Indices) -> ok
Types:
Indices = [integer()]
glMatrixIndexARB
See external documentation.
matrixIndexuivARB(Indices) -> ok
Types:
Indices = [integer()]
glMatrixIndexARB
See external documentation.
programStringARB(Target, Format, String) -> ok
Types:
Target = enum()
Format = enum()
String = string()
glProgramStringARB
See external documentation.
bindProgramARB(Target, Program) -> ok
Types:
Target = enum()
Program = integer()
glBindProgramARB
See external documentation.
deleteProgramsARB(Programs) -> ok
Types:
Programs = [integer()]
glDeleteProgramsARB
See external documentation.
genProgramsARB(N) -> [integer()]
Types:
N = integer()
glGenProgramsARB
See external documentation.
programEnvParameter4dARB(Target, Index, X, Y, Z, W) -> ok
Types:
Target = enum()
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
glProgramEnvParameterARB
See external documentation.
programEnvParameter4dvARB(Target, Index, Params) -> ok
Types:
Target = enum()
Index = integer()
Params = {float(), float(), float(), float()}
glProgramEnvParameterARB
See external documentation.
programEnvParameter4fARB(Target, Index, X, Y, Z, W) -> ok
Types:
Target = enum()
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
glProgramEnvParameterARB
See external documentation.
programEnvParameter4fvARB(Target, Index, Params) -> ok
Types:
Target = enum()
Index = integer()
Params = {float(), float(), float(), float()}
glProgramEnvParameterARB
See external documentation.
programLocalParameter4dARB(Target, Index, X, Y, Z, W) -> ok
Types:
Target = enum()
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
glProgramLocalParameterARB
See external documentation.
programLocalParameter4dvARB(Target, Index, Params) -> ok
Types:
Target = enum()
Index = integer()
Params = {float(), float(), float(), float()}
glProgramLocalParameterARB
See external documentation.
programLocalParameter4fARB(Target, Index, X, Y, Z, W) -> ok
Types:
Target = enum()
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
glProgramLocalParameterARB
See external documentation.
programLocalParameter4fvARB(Target, Index, Params) -> ok
Types:
Target = enum()
Index = integer()
Params = {float(), float(), float(), float()}
glProgramLocalParameterARB
See external documentation.
getProgramEnvParameterdvARB(Target, Index) -> {float(), float(), float(), float()}
Types:
Target = enum()
Index = integer()
glGetProgramEnvParameterARB
See external documentation.
getProgramEnvParameterfvARB(Target, Index) -> {float(), float(), float(), float()}
Types:
Target = enum()
Index = integer()
glGetProgramEnvParameterARB
See external documentation.
getProgramLocalParameterdvARB(Target, Index) -> {float(), float(), float(), float()}
Types:
Target = enum()
Index = integer()
glGetProgramLocalParameterARB
See external documentation.
getProgramLocalParameterfvARB(Target, Index) -> {float(), float(), float(), float()}
Types:
Target = enum()
Index = integer()
glGetProgramLocalParameterARB
See external documentation.
getProgramStringARB(Target, Pname, String) -> ok
Types:
Target = enum()
Pname = enum()
String = mem()
glGetProgramStringARB
See external documentation.
getBufferParameterivARB(Target, Pname) -> [integer()]
Types:
Target = enum()
Pname = enum()
glGetBufferParameterARB
See external documentation.
deleteObjectARB(Obj) -> ok
Types:
Obj = integer()
glDeleteObjectARB
See external documentation.
getHandleARB(Pname) -> integer()
Types:
Pname = enum()
glGetHandleARB
See external documentation.
detachObjectARB(ContainerObj, AttachedObj) -> ok
Types:
ContainerObj = integer()
AttachedObj = integer()
glDetachObjectARB
See external documentation.
createShaderObjectARB(ShaderType) -> integer()
Types:
ShaderType = enum()
glCreateShaderObjectARB
See external documentation.
shaderSourceARB(ShaderObj, String) -> ok
Types:
ShaderObj = integer()
String = [string()]
glShaderSourceARB
See external documentation.
compileShaderARB(ShaderObj) -> ok
Types:
ShaderObj = integer()
glCompileShaderARB
See external documentation.
createProgramObjectARB() -> integer()
glCreateProgramObjectARB
See external documentation.
attachObjectARB(ContainerObj, Obj) -> ok
Types:
ContainerObj = integer()
Obj = integer()
glAttachObjectARB
See external documentation.
linkProgramARB(ProgramObj) -> ok
Types:
ProgramObj = integer()
glLinkProgramARB
See external documentation.
useProgramObjectARB(ProgramObj) -> ok
Types:
ProgramObj = integer()
glUseProgramObjectARB
See external documentation.
validateProgramARB(ProgramObj) -> ok
Types:
ProgramObj = integer()
glValidateProgramARB
See external documentation.
getObjectParameterfvARB(Obj, Pname) -> float()
Types:
Obj = integer()
Pname = enum()
glGetObjectParameterARB
See external documentation.
getObjectParameterivARB(Obj, Pname) -> integer()
Types:
Obj = integer()
Pname = enum()
glGetObjectParameterARB
See external documentation.
getInfoLogARB(Obj, MaxLength) -> string()
Types:
Obj = integer()
MaxLength = integer()
glGetInfoLogARB
See external documentation.
getAttachedObjectsARB(ContainerObj, MaxCount) -> [integer()]
Types:
ContainerObj = integer()
MaxCount = integer()
glGetAttachedObjectsARB
See external documentation.
getUniformLocationARB(ProgramObj, Name) -> integer()
Types:
ProgramObj = integer()
Name = string()
glGetUniformLocationARB
See external documentation.
getActiveUniformARB(ProgramObj, Index, MaxLength) -> {Size::integer(), Type::enum(),
Name::string()}
Types:
ProgramObj = integer()
Index = integer()
MaxLength = integer()
glGetActiveUniformARB
See external documentation.
getUniformfvARB(ProgramObj, Location) -> matrix()
Types:
ProgramObj = integer()
Location = integer()
glGetUniformARB
See external documentation.
getUniformivARB(ProgramObj, Location) -> {integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer(), integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer()}
Types:
ProgramObj = integer()
Location = integer()
glGetUniformARB
See external documentation.
getShaderSourceARB(Obj, MaxLength) -> string()
Types:
Obj = integer()
MaxLength = integer()
glGetShaderSourceARB
See external documentation.
bindAttribLocationARB(ProgramObj, Index, Name) -> ok
Types:
ProgramObj = integer()
Index = integer()
Name = string()
glBindAttribLocationARB
See external documentation.
getActiveAttribARB(ProgramObj, Index, MaxLength) -> {Size::integer(), Type::enum(),
Name::string()}
Types:
ProgramObj = integer()
Index = integer()
MaxLength = integer()
glGetActiveAttribARB
See external documentation.
getAttribLocationARB(ProgramObj, Name) -> integer()
Types:
ProgramObj = integer()
Name = string()
glGetAttribLocationARB
See external documentation.
isRenderbuffer(Renderbuffer) -> 0 | 1
Types:
Renderbuffer = integer()
Determine if a name corresponds to a renderbuffer object
gl:isRenderbuffer returns ?GL_TRUE if Renderbuffer is currently the name of a
renderbuffer object. If Renderbuffer is zero, or if Renderbuffer is not the name of
a renderbuffer object, or if an error occurs, gl:isRenderbuffer returns ?GL_FALSE.
If Renderbuffer is a name returned by gl:genRenderbuffers/1 , by that has not yet
been bound through a call to gl:bindRenderbuffer/2 or gl:framebufferRenderbuffer/4
, then the name is not a renderbuffer object and gl:isRenderbuffer returns
?GL_FALSE .
See external documentation.
bindRenderbuffer(Target, Renderbuffer) -> ok
Types:
Target = enum()
Renderbuffer = integer()
Bind a renderbuffer to a renderbuffer target
gl:bindRenderbuffer binds the renderbuffer object with name Renderbuffer to the
renderbuffer target specified by Target . Target must be ?GL_RENDERBUFFER .
Renderbuffer is the name of a renderbuffer object previously returned from a call
to gl:genRenderbuffers/1 , or zero to break the existing binding of a renderbuffer
object to Target .
See external documentation.
deleteRenderbuffers(Renderbuffers) -> ok
Types:
Renderbuffers = [integer()]
Delete renderbuffer objects
gl:deleteRenderbuffers deletes the N renderbuffer objects whose names are stored in
the array addressed by Renderbuffers . The name zero is reserved by the GL and is
silently ignored, should it occur in Renderbuffers , as are other unused names.
Once a renderbuffer object is deleted, its name is again unused and it has no
contents. If a renderbuffer that is currently bound to the target ?GL_RENDERBUFFER
is deleted, it is as though gl:bindRenderbuffer/2 had been executed with a Target
of ?GL_RENDERBUFFER and a Name of zero.
If a renderbuffer object is attached to one or more attachment points in the
currently bound framebuffer, then it as if gl:framebufferRenderbuffer/4 had been
called, with a Renderbuffer of zero for each attachment point to which this image
was attached in the currently bound framebuffer. In other words, this renderbuffer
object is first detached from all attachment ponits in the currently bound
framebuffer. Note that the renderbuffer image is specifically not detached from any
non-bound framebuffers.
See external documentation.
genRenderbuffers(N) -> [integer()]
Types:
N = integer()
Generate renderbuffer object names
gl:genRenderbuffers returns N renderbuffer object names in Renderbuffers . There is
no guarantee that the names form a contiguous set of integers; however, it is
guaranteed that none of the returned names was in use immediately before the call
to gl:genRenderbuffers .
Renderbuffer object names returned by a call to gl:genRenderbuffers are not
returned by subsequent calls, unless they are first deleted with
gl:deleteRenderbuffers/1 .
The names returned in Renderbuffers are marked as used, for the purposes of
gl:genRenderbuffers only, but they acquire state and type only when they are first
bound.
See external documentation.
renderbufferStorage(Target, Internalformat, Width, Height) -> ok
Types:
Target = enum()
Internalformat = enum()
Width = integer()
Height = integer()
Establish data storage, format and dimensions of a renderbuffer object's image
gl:renderbufferStorage is equivalent to calling gl:renderbufferStorageMultisample/5
with the Samples set to zero.
The target of the operation, specified by Target must be ?GL_RENDERBUFFER.
Internalformat specifies the internal format to be used for the renderbuffer
object's storage and must be a color-renderable, depth-renderable, or stencil-
renderable format. Width and Height are the dimensions, in pixels, of the
renderbuffer. Both Width and Height must be less than or equal to the value of
?GL_MAX_RENDERBUFFER_SIZE .
Upon success, gl:renderbufferStorage deletes any existing data store for the
renderbuffer image and the contents of the data store after calling
gl:renderbufferStorage are undefined.
See external documentation.
getRenderbufferParameteriv(Target, Pname) -> integer()
Types:
Target = enum()
Pname = enum()
Retrieve information about a bound renderbuffer object
gl:getRenderbufferParameteriv retrieves information about a bound renderbuffer
object. Target specifies the target of the query operation and must be
?GL_RENDERBUFFER . Pname specifies the parameter whose value to query and must be
one of ?GL_RENDERBUFFER_WIDTH , ?GL_RENDERBUFFER_HEIGHT,
?GL_RENDERBUFFER_INTERNAL_FORMAT, ?GL_RENDERBUFFER_RED_SIZE ,
?GL_RENDERBUFFER_GREEN_SIZE, ?GL_RENDERBUFFER_BLUE_SIZE,
?GL_RENDERBUFFER_ALPHA_SIZE , ?GL_RENDERBUFFER_DEPTH_SIZE,
?GL_RENDERBUFFER_DEPTH_SIZE, ?GL_RENDERBUFFER_STENCIL_SIZE , or
?GL_RENDERBUFFER_SAMPLES.
Upon a successful return from gl:getRenderbufferParameteriv, if Pname is
?GL_RENDERBUFFER_WIDTH , ?GL_RENDERBUFFER_HEIGHT, ?GL_RENDERBUFFER_INTERNAL_FORMAT,
or ?GL_RENDERBUFFER_SAMPLES , then Params will contain the width in pixels, the
height in pixels, the internal format, or the number of samples, respectively, of
the image of the renderbuffer currently bound to Target .
If Pname is ?GL_RENDERBUFFER_RED_SIZE, ?GL_RENDERBUFFER_GREEN_SIZE,
?GL_RENDERBUFFER_BLUE_SIZE, ?GL_RENDERBUFFER_ALPHA_SIZE,
?GL_RENDERBUFFER_DEPTH_SIZE , or ?GL_RENDERBUFFER_STENCIL_SIZE, then Params will
contain the actual resolutions (not the resolutions specified when the image array
was defined) for the red, green, blue, alpha depth, or stencil components,
respectively, of the image of the renderbuffer currently bound to Target .
See external documentation.
isFramebuffer(Framebuffer) -> 0 | 1
Types:
Framebuffer = integer()
Determine if a name corresponds to a framebuffer object
gl:isFramebuffer returns ?GL_TRUE if Framebuffer is currently the name of a
framebuffer object. If Framebuffer is zero, or if ?framebuffer is not the name of a
framebuffer object, or if an error occurs, gl:isFramebuffer returns ?GL_FALSE. If
Framebuffer is a name returned by gl:genFramebuffers/1 , by that has not yet been
bound through a call to gl:bindFramebuffer/2 , then the name is not a framebuffer
object and gl:isFramebuffer returns ?GL_FALSE.
See external documentation.
bindFramebuffer(Target, Framebuffer) -> ok
Types:
Target = enum()
Framebuffer = integer()
Bind a framebuffer to a framebuffer target
gl:bindFramebuffer binds the framebuffer object with name Framebuffer to the
framebuffer target specified by Target . Target must be either ?GL_DRAW_FRAMEBUFFER
, ?GL_READ_FRAMEBUFFER or ?GL_FRAMEBUFFER. If a framebuffer object is bound to
?GL_DRAW_FRAMEBUFFER or ?GL_READ_FRAMEBUFFER, it becomes the target for rendering
or readback operations, respectively, until it is deleted or another framebuffer is
bound to the corresponding bind point. Calling gl:bindFramebuffer with Target set
to ?GL_FRAMEBUFFER binds Framebuffer to both the read and draw framebuffer targets.
Framebuffer is the name of a framebuffer object previously returned from a call to
gl:genFramebuffers/1 , or zero to break the existing binding of a framebuffer
object to Target .
See external documentation.
deleteFramebuffers(Framebuffers) -> ok
Types:
Framebuffers = [integer()]
Delete framebuffer objects
gl:deleteFramebuffers deletes the N framebuffer objects whose names are stored in
the array addressed by Framebuffers . The name zero is reserved by the GL and is
silently ignored, should it occur in Framebuffers , as are other unused names. Once
a framebuffer object is deleted, its name is again unused and it has no
attachments. If a framebuffer that is currently bound to one or more of the targets
?GL_DRAW_FRAMEBUFFER or ?GL_READ_FRAMEBUFFER is deleted, it is as though
gl:bindFramebuffer/2 had been executed with the corresponding Target and
Framebuffer zero.
See external documentation.
genFramebuffers(N) -> [integer()]
Types:
N = integer()
Generate framebuffer object names
gl:genFramebuffers returns N framebuffer object names in Ids . There is no
guarantee that the names form a contiguous set of integers; however, it is
guaranteed that none of the returned names was in use immediately before the call
to gl:genFramebuffers .
Framebuffer object names returned by a call to gl:genFramebuffers are not returned
by subsequent calls, unless they are first deleted with gl:deleteFramebuffers/1 .
The names returned in Ids are marked as used, for the purposes of
gl:genFramebuffers only, but they acquire state and type only when they are first
bound.
See external documentation.
checkFramebufferStatus(Target) -> enum()
Types:
Target = enum()
Check the completeness status of a framebuffer
gl:checkFramebufferStatus queries the completeness status of the framebuffer object
currently bound to Target . Target must be ?GL_DRAW_FRAMEBUFFER,
?GL_READ_FRAMEBUFFER or ?GL_FRAMEBUFFER. ?GL_FRAMEBUFFER is equivalent to
?GL_DRAW_FRAMEBUFFER .
The return value is ?GL_FRAMEBUFFER_COMPLETE if the framebuffer bound to Target is
complete. Otherwise, the return value is determined as follows:
?GL_FRAMEBUFFER_UNDEFINED is returned if Target is the default framebuffer, but the
default framebuffer does not exist.
?GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT is returned if any of the framebuffer
attachment points are framebuffer incomplete.
?GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT is returned if the framebuffer does
not have at least one image attached to it.
?GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER is returned if the value of
?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is ?GL_NONE for any color attachment
point(s) named by ?GL_DRAWBUFFERi.
?GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER is returned if ?GL_READ_BUFFER is not
?GL_NONE and the value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is ?GL_NONE for
the color attachment point named by ?GL_READ_BUFFER.
?GL_FRAMEBUFFER_UNSUPPORTED is returned if the combination of internal formats of
the attached images violates an implementation-dependent set of restrictions.
?GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE is returned if the value of
?GL_RENDERBUFFER_SAMPLES is not the same for all attached renderbuffers; if the
value of ?GL_TEXTURE_SAMPLES is the not same for all attached textures; or, if the
attached images are a mix of renderbuffers and textures, the value of
?GL_RENDERBUFFER_SAMPLES does not match the value of ?GL_TEXTURE_SAMPLES .
?GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE is also returned if the value of
?GL_TEXTURE_FIXED_SAMPLE_LOCATIONS is not the same for all attached textures; or,
if the attached images are a mix of renderbuffers and textures, the value of
?GL_TEXTURE_FIXED_SAMPLE_LOCATIONS is not ?GL_TRUE for all attached textures.
?GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS is returned if any framebuffer attachment
is layered, and any populated attachment is not layered, or if all populated color
attachments are not from textures of the same target.
Additionally, if an error occurs, zero is returned.
See external documentation.
framebufferTexture1D(Target, Attachment, Textarget, Texture, Level) -> ok
Types:
Target = enum()
Attachment = enum()
Textarget = enum()
Texture = integer()
Level = integer()
See framebufferTexture/4
framebufferTexture2D(Target, Attachment, Textarget, Texture, Level) -> ok
Types:
Target = enum()
Attachment = enum()
Textarget = enum()
Texture = integer()
Level = integer()
See framebufferTexture/4
framebufferTexture3D(Target, Attachment, Textarget, Texture, Level, Zoffset) -> ok
Types:
Target = enum()
Attachment = enum()
Textarget = enum()
Texture = integer()
Level = integer()
Zoffset = integer()
See framebufferTexture/4
framebufferRenderbuffer(Target, Attachment, Renderbuffertarget, Renderbuffer) -> ok
Types:
Target = enum()
Attachment = enum()
Renderbuffertarget = enum()
Renderbuffer = integer()
Attach a renderbuffer as a logical buffer to the currently bound framebuffer object
gl:framebufferRenderbuffer attaches a renderbuffer as one of the logical buffers of
the currently bound framebuffer object. Renderbuffer is the name of the
renderbuffer object to attach and must be either zero, or the name of an existing
renderbuffer object of type Renderbuffertarget . If Renderbuffer is not zero and if
gl:framebufferRenderbuffer is successful, then the renderbuffer name Renderbuffer
will be used as the logical buffer identified by Attachment of the framebuffer
currently bound to Target .
The value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE for the specified attachment
point is set to ?GL_RENDERBUFFER and the value of
?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME is set to Renderbuffer . All other state
values of the attachment point specified by Attachment are set to their default
values. No change is made to the state of the renderbuuffer object and any previous
attachment to the Attachment logical buffer of the framebuffer Target is broken.
Calling gl:framebufferRenderbuffer with the renderbuffer name zero will detach the
image, if any, identified by Attachment , in the framebuffer currently bound to
Target . All state values of the attachment point specified by attachment in the
object bound to target are set to their default values.
Setting Attachment to the value ?GL_DEPTH_STENCIL_ATTACHMENT is a special case
causing both the depth and stencil attachments of the framebuffer object to be set
to Renderbuffer , which should have the base internal format ?GL_DEPTH_STENCIL .
See external documentation.
getFramebufferAttachmentParameteriv(Target, Attachment, Pname) -> integer()
Types:
Target = enum()
Attachment = enum()
Pname = enum()
Retrieve information about attachments of a bound framebuffer object
gl:getFramebufferAttachmentParameter returns information about attachments of a
bound framebuffer object. Target specifies the framebuffer binding point and must
be ?GL_DRAW_FRAMEBUFFER, ?GL_READ_FRAMEBUFFER or ?GL_FRAMEBUFFER. ?GL_FRAMEBUFFER
is equivalent to ?GL_DRAW_FRAMEBUFFER.
If the default framebuffer is bound to Target then Attachment must be one of
?GL_FRONT_LEFT, ?GL_FRONT_RIGHT, ?GL_BACK_LEFT, or ?GL_BACK_RIGHT , identifying a
color buffer, ?GL_DEPTH, identifying the depth buffer, or ?GL_STENCIL , identifying
the stencil buffer.
If a framebuffer object is bound, then Attachment must be one of
?GL_COLOR_ATTACHMENT i, ?GL_DEPTH_ATTACHMENT, ?GL_STENCIL_ATTACHMENT, or
?GL_DEPTH_STENCIL_ATTACHMENT . i in ?GL_COLOR_ATTACHMENTi must be in the range zero
to the value of ?GL_MAX_COLOR_ATTACHMENTS - 1.
If Attachment is ?GL_DEPTH_STENCIL_ATTACHMENT and different objects are bound to
the depth and stencil attachment points of Target the query will fail. If the same
object is bound to both attachment points, information about that object will be
returned.
Upon successful return from gl:getFramebufferAttachmentParameteriv, if Pname is
?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, then Params will contain one of ?GL_NONE ,
?GL_FRAMEBUFFER_DEFAULT, ?GL_TEXTURE, or ?GL_RENDERBUFFER, identifying the type of
object which contains the attached image. Other values accepted for Pname depend on
the type of object, as described below.
If the value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is ?GL_NONE, no framebuffer
is bound to Target . In this case querying Pname
?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME will return zero, and all other queries will
generate an error.
If the value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is not ?GL_NONE, these
queries apply to all other framebuffer types:
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE,
?GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE , ?GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE,
?GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE , ?GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE, or
?GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE , then Params will contain the number of
bits in the corresponding red, green, blue, alpha, depth, or stencil component of
the specified attachment. Zero is returned if the requested component is not
present in Attachment .
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE, Params will contain the
format of components of the specified attachment, one of ?GL_FLOAT, GL_INT ,
GL_UNSIGNED_INT , GL_SIGNED_NORMALIZED , or GL_UNSIGNED_NORMALIZED for floating-
point, signed integer, unsigned integer, signed normalized fixed-point, or unsigned
normalized fixed-point components respectively. Only color buffers may have integer
components.
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING, Param will contain the
encoding of components of the specified attachment, one of ?GL_LINEAR or ?GL_SRGB
for linear or sRGB-encoded components, respectively. Only color buffer components
may be sRGB-encoded; such components are treated as described in sections 4.1.7 and
4.1.8. For the default framebuffer, color encoding is determined by the
implementation. For framebuffer objects, components are sRGB-encoded if the
internal format of a color attachment is one of the color-renderable SRGB formats.
If the value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is ?GL_RENDERBUFFER, then:
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, Params will contain the name of
the renderbuffer object which contains the attached image.
If the value of ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is ?GL_TEXTURE, then:
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, then Params will contain the
name of the texture object which contains the attached image.
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL, then Params will contain the
mipmap level of the texture object which contains the attached image.
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE and the texture object
named ?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME is a cube map texture, then Params
will contain the cube map face of the cubemap texture object which contains the
attached image. Otherwise Params will contain the value zero.
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER and the texture object named
?GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME is a layer of a three-dimensional texture or
a one-or two-dimensional array texture, then Params will contain the number of the
texture layer which contains the attached image. Otherwise Params will contain the
value zero.
If Pname is ?GL_FRAMEBUFFER_ATTACHMENT_LAYERED, then Params will contain ?GL_TRUE
if an entire level of a three-dimesional texture, cube map texture, or one-or two-
dimensional array texture is attached. Otherwise, Params will contain ?GL_FALSE.
Any combinations of framebuffer type and Pname not described above will generate an
error.
See external documentation.
generateMipmap(Target) -> ok
Types:
Target = enum()
Generate mipmaps for a specified texture target
gl:generateMipmap generates mipmaps for the texture attached to Target of the
active texture unit. For cube map textures, a ?GL_INVALID_OPERATION error is
generated if the texture attached to Target is not cube complete.
Mipmap generation replaces texel array levels level base+1 through q with arrays
derived from the level base array, regardless of their previous contents. All other
mimap arrays, including the level base array, are left unchanged by this
computation.
The internal formats of the derived mipmap arrays all match those of the level base
array. The contents of the derived arrays are computed by repeated, filtered
reduction of the level base array. For one- and two-dimensional texture arrays,
each layer is filtered independently.
See external documentation.
blitFramebuffer(SrcX0, SrcY0, SrcX1, SrcY1, DstX0, DstY0, DstX1, DstY1, Mask, Filter) ->
ok
Types:
SrcX0 = integer()
SrcY0 = integer()
SrcX1 = integer()
SrcY1 = integer()
DstX0 = integer()
DstY0 = integer()
DstX1 = integer()
DstY1 = integer()
Mask = integer()
Filter = enum()
Copy a block of pixels from the read framebuffer to the draw framebuffer
gl:blitFramebuffer transfers a rectangle of pixel values from one region of the
read framebuffer to another region in the draw framebuffer. Mask is the bitwise OR
of a number of values indicating which buffers are to be copied. The values are
?GL_COLOR_BUFFER_BIT , ?GL_DEPTH_BUFFER_BIT, and ?GL_STENCIL_BUFFER_BIT. The pixels
corresponding to these buffers are copied from the source rectangle bounded by the
locations ( SrcX0 ; SrcY0 ) and ( SrcX1 ; SrcY1 ) to the destination rectangle
bounded by the locations ( DstX0 ; DstY0 ) and ( DstX1 ; DstY1 ). The lower bounds
of the rectangle are inclusive, while the upper bounds are exclusive.
The actual region taken from the read framebuffer is limited to the intersection of
the source buffers being transferred, which may include the color buffer selected
by the read buffer, the depth buffer, and/or the stencil buffer depending on mask.
The actual region written to the draw framebuffer is limited to the intersection of
the destination buffers being written, which may include multiple draw buffers, the
depth buffer, and/or the stencil buffer depending on mask. Whether or not the
source or destination regions are altered due to these limits, the scaling and
offset applied to pixels being transferred is performed as though no such limits
were present.
If the sizes of the source and destination rectangles are not equal, Filter
specifies the interpolation method that will be applied to resize the source image
, and must be ?GL_NEAREST or ?GL_LINEAR. ?GL_LINEAR is only a valid interpolation
method for the color buffer. If Filter is not ?GL_NEAREST and Mask includes
?GL_DEPTH_BUFFER_BIT or ?GL_STENCIL_BUFFER_BIT, no data is transferred and a
?GL_INVALID_OPERATION error is generated.
If Filter is ?GL_LINEAR and the source rectangle would require sampling outside the
bounds of the source framebuffer, values are read as if the ?GL_CLAMP_TO_EDGE
texture wrapping mode were applied.
When the color buffer is transferred, values are taken from the read buffer of the
read framebuffer and written to each of the draw buffers of the draw framebuffer.
If the source and destination rectangles overlap or are the same, and the read and
draw buffers are the same, the result of the operation is undefined.
See external documentation.
renderbufferStorageMultisample(Target, Samples, Internalformat, Width, Height) -> ok
Types:
Target = enum()
Samples = integer()
Internalformat = enum()
Width = integer()
Height = integer()
Establish data storage, format, dimensions and sample count of a renderbuffer
object's image
gl:renderbufferStorageMultisample establishes the data storage, format, dimensions
and number of samples of a renderbuffer object's image.
The target of the operation, specified by Target must be ?GL_RENDERBUFFER.
Internalformat specifies the internal format to be used for the renderbuffer
object's storage and must be a color-renderable, depth-renderable, or stencil-
renderable format. Width and Height are the dimensions, in pixels, of the
renderbuffer. Both Width and Height must be less than or equal to the value of
?GL_MAX_RENDERBUFFER_SIZE . Samples specifies the number of samples to be used for
the renderbuffer object's image, and must be less than or equal to the value of
?GL_MAX_SAMPLES. If Internalformat is a signed or unsigned integer format then
Samples must be less than or equal to the value of ?GL_MAX_INTEGER_SAMPLES.
Upon success, gl:renderbufferStorageMultisample deletes any existing data store for
the renderbuffer image and the contents of the data store after calling
gl:renderbufferStorageMultisample are undefined.
See external documentation.
framebufferTextureLayer(Target, Attachment, Texture, Level, Layer) -> ok
Types:
Target = enum()
Attachment = enum()
Texture = integer()
Level = integer()
Layer = integer()
See framebufferTexture/4
framebufferTextureFaceARB(Target, Attachment, Texture, Level, Face) -> ok
Types:
Target = enum()
Attachment = enum()
Texture = integer()
Level = integer()
Face = enum()
See framebufferTexture/4
flushMappedBufferRange(Target, Offset, Length) -> ok
Types:
Target = enum()
Offset = integer()
Length = integer()
Indicate modifications to a range of a mapped buffer
gl:flushMappedBufferRange indicates that modifications have been made to a range of
a mapped buffer. The buffer must previously have been mapped with the
?GL_MAP_FLUSH_EXPLICIT flag. Offset and Length indicate the modified subrange of
the mapping, in basic units. The specified subrange to flush is relative to the
start of the currently mapped range of the buffer. gl:flushMappedBufferRange may be
called multiple times to indicate distinct subranges of the mapping which require
flushing.
See external documentation.
bindVertexArray(Array) -> ok
Types:
Array = integer()
Bind a vertex array object
gl:bindVertexArray binds the vertex array object with name Array . Array is the
name of a vertex array object previously returned from a call to
gl:genVertexArrays/1 , or zero to break the existing vertex array object binding.
If no vertex array object with name Array exists, one is created when Array is
first bound. If the bind is successful no change is made to the state of the vertex
array object, and any previous vertex array object binding is broken.
See external documentation.
deleteVertexArrays(Arrays) -> ok
Types:
Arrays = [integer()]
Delete vertex array objects
gl:deleteVertexArrays deletes N vertex array objects whose names are stored in the
array addressed by Arrays . Once a vertex array object is deleted it has no
contents and its name is again unused. If a vertex array object that is currently
bound is deleted, the binding for that object reverts to zero and the default
vertex array becomes current. Unused names in Arrays are silently ignored, as is
the value zero.
See external documentation.
genVertexArrays(N) -> [integer()]
Types:
N = integer()
Generate vertex array object names
gl:genVertexArrays returns N vertex array object names in Arrays . There is no
guarantee that the names form a contiguous set of integers; however, it is
guaranteed that none of the returned names was in use immediately before the call
to gl:genVertexArrays .
Vertex array object names returned by a call to gl:genVertexArrays are not returned
by subsequent calls, unless they are first deleted with gl:deleteVertexArrays/1 .
The names returned in Arrays are marked as used, for the purposes of
gl:genVertexArrays only, but they acquire state and type only when they are first
bound.
See external documentation.
isVertexArray(Array) -> 0 | 1
Types:
Array = integer()
Determine if a name corresponds to a vertex array object
gl:isVertexArray returns ?GL_TRUE if Array is currently the name of a renderbuffer
object. If Renderbuffer is zero, or if Array is not the name of a renderbuffer
object, or if an error occurs, gl:isVertexArray returns ?GL_FALSE . If Array is a
name returned by gl:genVertexArrays/1 , by that has not yet been bound through a
call to gl:bindVertexArray/1 , then the name is not a vertex array object and
gl:isVertexArray returns ?GL_FALSE.
See external documentation.
getUniformIndices(Program, UniformNames) -> [integer()]
Types:
Program = integer()
UniformNames = [string()]
Retrieve the index of a named uniform block
gl:getUniformIndices retrieves the indices of a number of uniforms within Program .
Program must be the name of a program object for which the command gl:linkProgram/1
must have been called in the past, although it is not required that
gl:linkProgram/1 must have succeeded. The link could have failed because the number
of active uniforms exceeded the limit.
UniformCount indicates both the number of elements in the array of names
UniformNames and the number of indices that may be written to UniformIndices .
UniformNames contains a list of UniformCount name strings identifying the uniform
names to be queried for indices. For each name string in UniformNames , the index
assigned to the active uniform of that name will be written to the corresponding
element of UniformIndices . If a string in UniformNames is not the name of an
active uniform, the special value ?GL_INVALID_INDEX will be written to the
corresponding element of UniformIndices .
If an error occurs, nothing is written to UniformIndices .
See external documentation.
getActiveUniformsiv(Program, UniformIndices, Pname) -> [integer()]
Types:
Program = integer()
UniformIndices = [integer()]
Pname = enum()
glGetActiveUniforms
See external documentation.
getActiveUniformName(Program, UniformIndex, BufSize) -> string()
Types:
Program = integer()
UniformIndex = integer()
BufSize = integer()
Query the name of an active uniform
gl:getActiveUniformName returns the name of the active uniform at UniformIndex
within Program . If UniformName is not NULL, up to BufSize characters (including a
nul-terminator) will be written into the array whose address is specified by
UniformName . If Length is not NULL, the number of characters that were (or would
have been) written into UniformName (not including the nul-terminator) will be
placed in the variable whose address is specified in Length . If Length is NULL, no
length is returned. The length of the longest uniform name in Program is given by
the value of ?GL_ACTIVE_UNIFORM_MAX_LENGTH, which can be queried with
gl:getProgramiv/2 .
If gl:getActiveUniformName is not successful, nothing is written to Length or
UniformName .
Program must be the name of a program for which the command gl:linkProgram/1 has
been issued in the past. It is not necessary for Program to have been linked
successfully. The link could have failed because the number of active uniforms
exceeded the limit.
UniformIndex must be an active uniform index of the program Program , in the range
zero to ?GL_ACTIVE_UNIFORMS - 1. The value of ?GL_ACTIVE_UNIFORMS can be queried
with gl:getProgramiv/2 .
See external documentation.
getUniformBlockIndex(Program, UniformBlockName) -> integer()
Types:
Program = integer()
UniformBlockName = string()
Retrieve the index of a named uniform block
gl:getUniformBlockIndex retrieves the index of a uniform block within Program .
Program must be the name of a program object for which the command gl:linkProgram/1
must have been called in the past, although it is not required that
gl:linkProgram/1 must have succeeded. The link could have failed because the number
of active uniforms exceeded the limit.
UniformBlockName must contain a nul-terminated string specifying the name of the
uniform block.
gl:getUniformBlockIndex returns the uniform block index for the uniform block named
UniformBlockName of Program . If UniformBlockName does not identify an active
uniform block of Program , gl:getUniformBlockIndex returns the special identifier,
?GL_INVALID_INDEX. Indices of the active uniform blocks of a program are assigned
in consecutive order, beginning with zero.
See external documentation.
getActiveUniformBlockiv(Program, UniformBlockIndex, Pname, Params) -> ok
Types:
Program = integer()
UniformBlockIndex = integer()
Pname = enum()
Params = mem()
Query information about an active uniform block
gl:getActiveUniformBlockiv retrieves information about an active uniform block
within Program .
Program must be the name of a program object for which the command gl:linkProgram/1
must have been called in the past, although it is not required that
gl:linkProgram/1 must have succeeded. The link could have failed because the number
of active uniforms exceeded the limit.
UniformBlockIndex is an active uniform block index of Program , and must be less
than the value of ?GL_ACTIVE_UNIFORM_BLOCKS.
Upon success, the uniform block parameter(s) specified by Pname are returned in
Params . If an error occurs, nothing will be written to Params .
If Pname is ?GL_UNIFORM_BLOCK_BINDING, then the index of the uniform buffer binding
point last selected by the uniform block specified by UniformBlockIndex for Program
is returned. If no uniform block has been previously specified, zero is returned.
If Pname is ?GL_UNIFORM_BLOCK_DATA_SIZE, then the implementation-dependent minimum
total buffer object size, in basic machine units, required to hold all active
uniforms in the uniform block identified by UniformBlockIndex is returned. It is
neither guaranteed nor expected that a given implementation will arrange uniform
values as tightly packed in a buffer object. The exception to this is the std140
uniform block layout , which guarantees specific packing behavior and does not
require the application to query for offsets and strides. In this case the minimum
size may still be queried, even though it is determined in advance based only on
the uniform block declaration.
If Pname is ?GL_UNIFORM_BLOCK_NAME_LENGTH, then the total length (including the nul
terminator) of the name of the uniform block identified by UniformBlockIndex is
returned.
If Pname is ?GL_UNIFORM_BLOCK_ACTIVE_UNIFORMS, then the number of active uniforms
in the uniform block identified by UniformBlockIndex is returned.
If Pname is ?GL_UNIFORM_BLOCK_ACTIVE_UNIFORM_INDICES, then a list of the active
uniform indices for the uniform block identified by UniformBlockIndex is returned.
The number of elements that will be written to Params is the value of
?GL_UNIFORM_BLOCK_ACTIVE_UNIFORMS for UniformBlockIndex .
If Pname is ?GL_UNIFORM_BLOCK_REFERENCED_BY_VERTEX_SHADER,
?GL_UNIFORM_BLOCK_REFERENCED_BY_GEOMETRY_SHADER , or
?GL_UNIFORM_BLOCK_REFERENCED_BY_FRAGMENT_SHADER, then a boolean value indicating
whether the uniform block identified by UniformBlockIndex is referenced by the
vertex, geometry, or fragment programming stages of program, respectively, is
returned.
See external documentation.
getActiveUniformBlockName(Program, UniformBlockIndex, BufSize) -> string()
Types:
Program = integer()
UniformBlockIndex = integer()
BufSize = integer()
Retrieve the name of an active uniform block
gl:getActiveUniformBlockName retrieves the name of the active uniform block at
UniformBlockIndex within Program .
Program must be the name of a program object for which the command gl:linkProgram/1
must have been called in the past, although it is not required that
gl:linkProgram/1 must have succeeded. The link could have failed because the number
of active uniforms exceeded the limit.
UniformBlockIndex is an active uniform block index of Program , and must be less
than the value of ?GL_ACTIVE_UNIFORM_BLOCKS.
Upon success, the name of the uniform block identified by UnifomBlockIndex is
returned into UniformBlockName . The name is nul-terminated. The actual number of
characters written into UniformBlockName , excluding the nul terminator, is
returned in Length . If Length is NULL, no length is returned.
BufSize contains the maximum number of characters (including the nul terminator)
that will be written into UniformBlockName .
If an error occurs, nothing will be written to UniformBlockName or Length .
See external documentation.
uniformBlockBinding(Program, UniformBlockIndex, UniformBlockBinding) -> ok
Types:
Program = integer()
UniformBlockIndex = integer()
UniformBlockBinding = integer()
Assign a binding point to an active uniform block
Binding points for active uniform blocks are assigned using gl:uniformBlockBinding.
Each of a program's active uniform blocks has a corresponding uniform buffer
binding point. Program is the name of a program object for which the command
gl:linkProgram/1 has been issued in the past.
If successful, gl:uniformBlockBinding specifies that Program will use the data
store of the buffer object bound to the binding point UniformBlockBinding to
extract the values of the uniforms in the uniform block identified by
UniformBlockIndex .
When a program object is linked or re-linked, the uniform buffer object binding
point assigned to each of its active uniform blocks is reset to zero.
See external documentation.
copyBufferSubData(ReadTarget, WriteTarget, ReadOffset, WriteOffset, Size) -> ok
Types:
ReadTarget = enum()
WriteTarget = enum()
ReadOffset = integer()
WriteOffset = integer()
Size = integer()
Copy part of the data store of a buffer object to the data store of another buffer
object
gl:copyBufferSubData copies part of the data store attached to Readtarget to the
data store attached to Writetarget . The number of basic machine units indicated by
Size is copied from the source, at offset Readoffset to the destination at
Writeoffset , also in basic machine units.
Readtarget and Writetarget must be ?GL_ARRAY_BUFFER, ?GL_COPY_READ_BUFFER ,
?GL_COPY_WRITE_BUFFER, ?GL_ELEMENT_ARRAY_BUFFER, ?GL_PIXEL_PACK_BUFFER ,
?GL_PIXEL_UNPACK_BUFFER, ?GL_TEXTURE_BUFFER, ?GL_TRANSFORM_FEEDBACK_BUFFER or
?GL_UNIFORM_BUFFER. Any of these targets may be used, although the targets
?GL_COPY_READ_BUFFER and ?GL_COPY_WRITE_BUFFER are provided specifically to allow
copies between buffers without disturbing other GL state.
Readoffset , Writeoffset and Size must all be greater than or equal to zero.
Furthermore, Readoffset + Size must not exceeed the size of the buffer object bound
to Readtarget , and Readoffset + Size must not exceeed the size of the buffer bound
to Writetarget . If the same buffer object is bound to both Readtarget and
Writetarget , then the ranges specified by Readoffset , Writeoffset and Size must
not overlap.
See external documentation.
drawElementsBaseVertex(Mode, Count, Type, Indices, Basevertex) -> ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Basevertex = integer()
Render primitives from array data with a per-element offset
gl:drawElementsBaseVertex behaves identically to gl:drawElements/4 except that the
ith element transferred by the corresponding draw call will be taken from element
Indices [i] + Basevertex of each enabled array. If the resulting value is larger
than the maximum value representable by Type , it is as if the calculation were
upconverted to 32-bit unsigned integers (with wrapping on overflow conditions). The
operation is undefined if the sum would be negative.
See external documentation.
drawRangeElementsBaseVertex(Mode, Start, End, Count, Type, Indices, Basevertex) -> ok
Types:
Mode = enum()
Start = integer()
End = integer()
Count = integer()
Type = enum()
Indices = offset() | mem()
Basevertex = integer()
Render primitives from array data with a per-element offset
gl:drawRangeElementsBaseVertex is a restricted form of gl:drawElementsBaseVertex/5
. Mode , Start , End , Count and Basevertex match the corresponding arguments to
gl:drawElementsBaseVertex/5 , with the additional constraint that all values in the
array Indices must lie between Start and End , inclusive, prior to adding
Basevertex . Index values lying outside the range [ Start , End ] are treated in
the same way as gl:drawElementsBaseVertex/5 . The i th element transferred by the
corresponding draw call will be taken from element Indices [i] + Basevertex of each
enabled array. If the resulting value is larger than the maximum value
representable by Type , it is as if the calculation were upconverted to 32-bit
unsigned integers (with wrapping on overflow conditions). The operation is
undefined if the sum would be negative.
See external documentation.
drawElementsInstancedBaseVertex(Mode, Count, Type, Indices, Primcount, Basevertex) -> ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Primcount = integer()
Basevertex = integer()
Render multiple instances of a set of primitives from array data with a per-element
offset
gl:drawElementsInstancedBaseVertex behaves identically to
gl:drawElementsInstanced/5 except that the ith element transferred by the
corresponding draw call will be taken from element Indices [i] + Basevertex of each
enabled array. If the resulting value is larger than the maximum value
representable by Type , it is as if the calculation were upconverted to 32-bit
unsigned integers (with wrapping on overflow conditions). The operation is
undefined if the sum would be negative.
See external documentation.
provokingVertex(Mode) -> ok
Types:
Mode = enum()
Specifiy the vertex to be used as the source of data for flat shaded varyings
Flatshading a vertex shader varying output means to assign all vetices of the
primitive the same value for that output. The vertex from which these values is
derived is known as the provoking vertex and gl:provokingVertex specifies which
vertex is to be used as the source of data for flat shaded varyings.
ProvokeMode must be either ?GL_FIRST_VERTEX_CONVENTION or
?GL_LAST_VERTEX_CONVENTION , and controls the selection of the vertex whose values
are assigned to flatshaded varying outputs. The interpretation of these values for
the supported primitive types is:Primitive Type of PolygoniFirst Vertex
ConventionLast Vertex Convention
point ii
independent line 2i - 1 2i
line loop i
i + 1, if i < n 1, if i = n
line strip ii + 1
independent triangle 3i - 2 3i
triangle strip ii + 2
triangle fan i + 1 i + 2
line adjacency 4i - 2 4i - 1
line strip adjacency i + 1 i + 2
triangle adjacency 6i - 5 6i - 1
triangle strip adjacency 2i - 1 2i + 3
If a vertex or geometry shader is active, user-defined varying outputs may be
flatshaded by using the flat qualifier when declaring the output.
See external documentation.
fenceSync(Condition, Flags) -> integer()
Types:
Condition = enum()
Flags = integer()
Create a new sync object and insert it into the GL command stream
gl:fenceSync creates a new fence sync object, inserts a fence command into the GL
command stream and associates it with that sync object, and returns a non-zero name
corresponding to the sync object.
When the specified Condition of the sync object is satisfied by the fence command,
the sync object is signaled by the GL, causing any gl:waitSync/3 ,
gl:clientWaitSync/3 commands blocking in Sync to unblock. No other state is
affected by gl:fenceSync or by the execution of the associated fence command.
Condition must be ?GL_SYNC_GPU_COMMANDS_COMPLETE. This condition is satisfied by
completion of the fence command corresponding to the sync object and all preceding
commands in the same command stream. The sync object will not be signaled until all
effects from these commands on GL client and server state and the framebuffer are
fully realized. Note that completion of the fence command occurs once the state of
the corresponding sync object has been changed, but commands waiting on that sync
object may not be unblocked until after the fence command completes.
See external documentation.
isSync(Sync) -> 0 | 1
Types:
Sync = integer()
Determine if a name corresponds to a sync object
gl:isSync returns ?GL_TRUE if Sync is currently the name of a sync object. If Sync
is not the name of a sync object, or if an error occurs, gl:isSync returns
?GL_FALSE. Note that zero is not the name of a sync object.
See external documentation.
deleteSync(Sync) -> ok
Types:
Sync = integer()
Delete a sync object
gl:deleteSync deletes the sync object specified by Sync . If the fence command
corresponding to the specified sync object has completed, or if no gl:waitSync/3 or
gl:clientWaitSync/3 commands are blocking on Sync , the object is deleted
immediately. Otherwise, Sync is flagged for deletion and will be deleted when it is
no longer associated with any fence command and is no longer blocking any
gl:waitSync/3 or gl:clientWaitSync/3 command. In either case, after gl:deleteSync
returns, the name Sync is invalid and can no longer be used to refer to the sync
object.
gl:deleteSync will silently ignore a Sync value of zero.
See external documentation.
clientWaitSync(Sync, Flags, Timeout) -> enum()
Types:
Sync = integer()
Flags = integer()
Timeout = integer()
Block and wait for a sync object to become signaled
gl:clientWaitSync causes the client to block and wait for the sync object specified
by Sync to become signaled. If Sync is signaled when gl:clientWaitSync is called,
gl:clientWaitSync returns immediately, otherwise it will block and wait for up to
Timeout nanoseconds for Sync to become signaled.
The return value is one of four status values:
?GL_ALREADY_SIGNALED indicates that Sync was signaled at the time that
gl:clientWaitSync was called.
?GL_TIMEOUT_EXPIRED indicates that at least Timeout nanoseconds passed and Sync did
not become signaled.
?GL_CONDITION_SATISFIED indicates that Sync was signaled before the timeout
expired.
?GL_WAIT_FAILED indicates that an error occurred. Additionally, an OpenGL error
will be generated.
See external documentation.
waitSync(Sync, Flags, Timeout) -> ok
Types:
Sync = integer()
Flags = integer()
Timeout = integer()
Instruct the GL server to block until the specified sync object becomes signaled
gl:waitSync causes the GL server to block and wait until Sync becomes signaled.
Sync is the name of an existing sync object upon which to wait. Flags and Timeout
are currently not used and must be set to zero and the special value
?GL_TIMEOUT_IGNORED , respectively
Flags and Timeout are placeholders for anticipated future extensions of sync object
capabilities. They must have these reserved values in order that existing code
calling gl:waitSync operate properly in the presence of such extensions..
gl:waitSync will always wait no longer than an implementation-dependent timeout.
The duration of this timeout in nanoseconds may be queried by calling
gl:getBooleanv/1 with the parameter ?GL_MAX_SERVER_WAIT_TIMEOUT . There is
currently no way to determine whether gl:waitSync unblocked because the timeout
expired or because the sync object being waited on was signaled.
If an error occurs, gl:waitSync does not cause the GL server to block.
See external documentation.
getInteger64v(Pname) -> [integer()]
Types:
Pname = enum()
See getBooleanv/1
getSynciv(Sync, Pname, BufSize) -> [integer()]
Types:
Sync = integer()
Pname = enum()
BufSize = integer()
Query the properties of a sync object
gl:getSynciv retrieves properties of a sync object. Sync specifies the name of the
sync object whose properties to retrieve.
On success, gl:getSynciv replaces up to BufSize integers in Values with the
corresponding property values of the object being queried. The actual number of
integers replaced is returned in the variable whose address is specified in Length
. If Length is NULL, no length is returned.
If Pname is ?GL_OBJECT_TYPE, a single value representing the specific type of the
sync object is placed in Values . The only type supported is ?GL_SYNC_FENCE .
If Pname is ?GL_SYNC_STATUS, a single value representing the status of the sync
object (?GL_SIGNALED or ?GL_UNSIGNALED) is placed in Values .
If Pname is ?GL_SYNC_CONDITION, a single value representing the condition of the
sync object is placed in Values . The only condition supported is
?GL_SYNC_GPU_COMMANDS_COMPLETE .
If Pname is ?GL_SYNC_FLAGS, a single value representing the flags with which the
sync object was created is placed in Values . No flags are currently supported
Flags is expected to be used in future extensions to the sync objects..
If an error occurs, nothing will be written to Values or Length .
See external documentation.
texImage2DMultisample(Target, Samples, Internalformat, Width, Height,
Fixedsamplelocations) -> ok
Types:
Target = enum()
Samples = integer()
Internalformat = integer()
Width = integer()
Height = integer()
Fixedsamplelocations = 0 | 1
Establish the data storage, format, dimensions, and number of samples of a
multisample texture's image
gl:texImage2DMultisample establishes the data storage, format, dimensions and
number of samples of a multisample texture's image.
Target must be ?GL_TEXTURE_2D_MULTISAMPLE or ?GL_PROXY_TEXTURE_2D_MULTISAMPLE .
Width and Height are the dimensions in texels of the texture, and must be in the
range zero to ?GL_MAX_TEXTURE_SIZE - 1. Samples specifies the number of samples in
the image and must be in the range zero to ?GL_MAX_SAMPLES - 1.
Internalformat must be a color-renderable, depth-renderable, or stencil-renderable
format.
If Fixedsamplelocations is ?GL_TRUE, the image will use identical sample locations
and the same number of samples for all texels in the image, and the sample
locations will not depend on the internal format or size of the image.
When a multisample texture is accessed in a shader, the access takes one vector of
integers describing which texel to fetch and an integer corresponding to the sample
numbers describing which sample within the texel to fetch. No standard sampling
instructions are allowed on the multisample texture targets.
See external documentation.
texImage3DMultisample(Target, Samples, Internalformat, Width, Height, Depth,
Fixedsamplelocations) -> ok
Types:
Target = enum()
Samples = integer()
Internalformat = integer()
Width = integer()
Height = integer()
Depth = integer()
Fixedsamplelocations = 0 | 1
Establish the data storage, format, dimensions, and number of samples of a
multisample texture's image
gl:texImage3DMultisample establishes the data storage, format, dimensions and
number of samples of a multisample texture's image.
Target must be ?GL_TEXTURE_2D_MULTISAMPLE_ARRAY or
?GL_PROXY_TEXTURE_2D_MULTISAMPLE_ARRAY . Width and Height are the dimensions in
texels of the texture, and must be in the range zero to ?GL_MAX_TEXTURE_SIZE - 1.
Depth is the number of array slices in the array texture's image. Samples specifies
the number of samples in the image and must be in the range zero to ?GL_MAX_SAMPLES
- 1.
Internalformat must be a color-renderable, depth-renderable, or stencil-renderable
format.
If Fixedsamplelocations is ?GL_TRUE, the image will use identical sample locations
and the same number of samples for all texels in the image, and the sample
locations will not depend on the internal format or size of the image.
When a multisample texture is accessed in a shader, the access takes one vector of
integers describing which texel to fetch and an integer corresponding to the sample
numbers describing which sample within the texel to fetch. No standard sampling
instructions are allowed on the multisample texture targets.
See external documentation.
getMultisamplefv(Pname, Index) -> {float(), float()}
Types:
Pname = enum()
Index = integer()
Retrieve the location of a sample
gl:getMultisamplefv queries the location of a given sample. Pname specifies the
sample parameter to retrieve and must be ?GL_SAMPLE_POSITION. Index corresponds to
the sample for which the location should be returned. The sample location is
returned as two floating-point values in Val[0] and Val[1] , each between 0 and 1,
corresponding to the X and Y locations respectively in the GL pixel space of that
sample. (0.5, 0.5) this corresponds to the pixel center. Index must be between zero
and the value of ?GL_SAMPLES - 1.
If the multisample mode does not have fixed sample locations, the returned values
may only reflect the locations of samples within some pixels.
See external documentation.
sampleMaski(Index, Mask) -> ok
Types:
Index = integer()
Mask = integer()
Set the value of a sub-word of the sample mask
gl:sampleMaski sets one 32-bit sub-word of the multi-word sample mask,
?GL_SAMPLE_MASK_VALUE .
MaskIndex specifies which 32-bit sub-word of the sample mask to update, and Mask
specifies the new value to use for that sub-word. MaskIndex must be less than the
value of ?GL_MAX_SAMPLE_MASK_WORDS. Bit B of mask word M corresponds to sample 32 x
M + B.
See external documentation.
namedStringARB(Type, Name, String) -> ok
Types:
Type = enum()
Name = string()
String = string()
glNamedStringARB
See external documentation.
deleteNamedStringARB(Name) -> ok
Types:
Name = string()
glDeleteNamedStringARB
See external documentation.
compileShaderIncludeARB(Shader, Path) -> ok
Types:
Shader = integer()
Path = [string()]
glCompileShaderIncludeARB
See external documentation.
isNamedStringARB(Name) -> 0 | 1
Types:
Name = string()
glIsNamedStringARB
See external documentation.
getNamedStringARB(Name, BufSize) -> string()
Types:
Name = string()
BufSize = integer()
glGetNamedStringARB
See external documentation.
getNamedStringivARB(Name, Pname) -> integer()
Types:
Name = string()
Pname = enum()
glGetNamedStringARB
See external documentation.
bindFragDataLocationIndexed(Program, ColorNumber, Index, Name) -> ok
Types:
Program = integer()
ColorNumber = integer()
Index = integer()
Name = string()
glBindFragDataLocationIndexe
See external documentation.
getFragDataIndex(Program, Name) -> integer()
Types:
Program = integer()
Name = string()
Query the bindings of color indices to user-defined varying out variables
gl:getFragDataIndex returns the index of the fragment color to which the variable
Name was bound when the program object Program was last linked. If Name is not a
varying out variable of Program , or if an error occurs, -1 will be returned.
See external documentation.
genSamplers(Count) -> [integer()]
Types:
Count = integer()
Generate sampler object names
gl:genSamplers returns N sampler object names in Samplers . There is no guarantee
that the names form a contiguous set of integers; however, it is guaranteed that
none of the returned names was in use immediately before the call to gl:genSamplers
.
Sampler object names returned by a call to gl:genSamplers are not returned by
subsequent calls, unless they are first deleted with gl:deleteSamplers/1 .
The names returned in Samplers are marked as used, for the purposes of
gl:genSamplers only, but they acquire state and type only when they are first
bound.
See external documentation.
deleteSamplers(Samplers) -> ok
Types:
Samplers = [integer()]
Delete named sampler objects
gl:deleteSamplers deletes N sampler objects named by the elements of the array Ids
. After a sampler object is deleted, its name is again unused. If a sampler object
that is currently bound to a sampler unit is deleted, it is as though
gl:bindSampler/2 is called with unit set to the unit the sampler is bound to and
sampler zero. Unused names in samplers are silently ignored, as is the reserved
name zero.
See external documentation.
isSampler(Sampler) -> 0 | 1
Types:
Sampler = integer()
Determine if a name corresponds to a sampler object
gl:isSampler returns ?GL_TRUE if Id is currently the name of a sampler object. If
Id is zero, or is a non-zero value that is not currently the name of a sampler
object, or if an error occurs, gl:isSampler returns ?GL_FALSE.
A name returned by gl:genSamplers/1 , is the name of a sampler object.
See external documentation.
bindSampler(Unit, Sampler) -> ok
Types:
Unit = integer()
Sampler = integer()
Bind a named sampler to a texturing target
gl:bindSampler binds Sampler to the texture unit at index Unit . Sampler must be
zero or the name of a sampler object previously returned from a call to
gl:genSamplers/1 . Unit must be less than the value of
?GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS.
When a sampler object is bound to a texture unit, its state supersedes that of the
texture object bound to that texture unit. If the sampler name zero is bound to a
texture unit, the currently bound texture's sampler state becomes active. A single
sampler object may be bound to multiple texture units simultaneously.
See external documentation.
samplerParameteri(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = integer()
Set sampler parameters
gl:samplerParameter assigns the value or values in Params to the sampler parameter
specified as Pname . Sampler specifies the sampler object to be modified, and must
be the name of a sampler object previously returned from a call to gl:genSamplers/1
. The following symbols are accepted in Pname :
?GL_TEXTURE_MIN_FILTER: The texture minifying function is used whenever the pixel
being textured maps to an area greater than one texture element. There are six
defined minifying functions. Two of them use the nearest one or nearest four
texture elements to compute the texture value. The other four use mipmaps.
A mipmap is an ordered set of arrays representing the same image at progressively
lower resolutions. If the texture has dimensions 2 n×2 m, there are max(n m)+1
mipmaps. The first mipmap is the original texture, with dimensions 2 n×2 m. Each
subsequent mipmap has dimensions 2(k-1)×2(l-1), where 2 k×2 l are the dimensions of
the previous mipmap, until either k=0 or l=0. At that point, subsequent mipmaps
have dimension 1×2(l-1) or 2(k-1)×1 until the final mipmap, which has dimension
1×1. To define the mipmaps, call gl:texImage1D/8 , gl:texImage2D/9 ,
gl:texImage3D/10 , gl:copyTexImage1D/7 , or gl:copyTexImage2D/8 with the level
argument indicating the order of the mipmaps. Level 0 is the original texture;
level max(n m) is the final 1×1 mipmap.
Params supplies a function for minifying the texture as one of the following:
?GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan
distance) to the center of the pixel being textured.
?GL_LINEAR: Returns the weighted average of the four texture elements that are
closest to the center of the pixel being textured. These can include border texture
elements, depending on the values of ?GL_TEXTURE_WRAP_S and ?GL_TEXTURE_WRAP_T, and
on the exact mapping.
?GL_NEAREST_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size
of the pixel being textured and uses the ?GL_NEAREST criterion (the texture element
nearest to the center of the pixel) to produce a texture value.
?GL_LINEAR_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size of
the pixel being textured and uses the ?GL_LINEAR criterion (a weighted average of
the four texture elements that are closest to the center of the pixel) to produce a
texture value.
?GL_NEAREST_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size
of the pixel being textured and uses the ?GL_NEAREST criterion (the texture element
nearest to the center of the pixel) to produce a texture value from each mipmap.
The final texture value is a weighted average of those two values.
?GL_LINEAR_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size
of the pixel being textured and uses the ?GL_LINEAR criterion (a weighted average
of the four texture elements that are closest to the center of the pixel) to
produce a texture value from each mipmap. The final texture value is a weighted
average of those two values.
As more texture elements are sampled in the minification process, fewer aliasing
artifacts will be apparent. While the ?GL_NEAREST and ?GL_LINEAR minification
functions can be faster than the other four, they sample only one or four texture
elements to determine the texture value of the pixel being rendered and can produce
moire patterns or ragged transitions. The initial value of ?GL_TEXTURE_MIN_FILTER
is ?GL_NEAREST_MIPMAP_LINEAR .
?GL_TEXTURE_MAG_FILTER: The texture magnification function is used when the pixel
being textured maps to an area less than or equal to one texture element. It sets
the texture magnification function to either ?GL_NEAREST or ?GL_LINEAR (see below).
?GL_NEAREST is generally faster than ?GL_LINEAR, but it can produce textured images
with sharper edges because the transition between texture elements is not as
smooth. The initial value of ?GL_TEXTURE_MAG_FILTER is ?GL_LINEAR.
?GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan
distance) to the center of the pixel being textured.
?GL_LINEAR: Returns the weighted average of the four texture elements that are
closest to the center of the pixel being textured. These can include border texture
elements, depending on the values of ?GL_TEXTURE_WRAP_S and ?GL_TEXTURE_WRAP_T, and
on the exact mapping.
?GL_TEXTURE_MIN_LOD: Sets the minimum level-of-detail parameter. This floating-
point value limits the selection of highest resolution mipmap (lowest mipmap
level). The initial value is -1000.
?GL_TEXTURE_MAX_LOD: Sets the maximum level-of-detail parameter. This floating-
point value limits the selection of the lowest resolution mipmap (highest mipmap
level). The initial value is 1000.
?GL_TEXTURE_WRAP_S: Sets the wrap parameter for texture coordinate s to either
?GL_CLAMP_TO_EDGE , ?GL_MIRRORED_REPEAT, or ?GL_REPEAT. ?GL_CLAMP_TO_BORDER causes
the s coordinate to be clamped to the range [(-1 2/N) 1+(1 2/N)], where N is the
size of the texture in the direction of clamping.?GL_CLAMP_TO_EDGE causes s
coordinates to be clamped to the range [(1 2/N) 1-(1 2/N)], where N is the size of
the texture in the direction of clamping. ?GL_REPEAT causes the integer part of the
s coordinate to be ignored; the GL uses only the fractional part, thereby creating
a repeating pattern. ?GL_MIRRORED_REPEAT causes the s coordinate to be set to the
fractional part of the texture coordinate if the integer part of s is even; if the
integer part of s is odd, then the s texture coordinate is set to 1-frac(s), where
frac(s) represents the fractional part of s. Initially, ?GL_TEXTURE_WRAP_S is set
to ?GL_REPEAT.
?GL_TEXTURE_WRAP_T: Sets the wrap parameter for texture coordinate t to either
?GL_CLAMP_TO_EDGE , ?GL_MIRRORED_REPEAT, or ?GL_REPEAT. See the discussion under
?GL_TEXTURE_WRAP_S . Initially, ?GL_TEXTURE_WRAP_T is set to ?GL_REPEAT.
?GL_TEXTURE_WRAP_R: Sets the wrap parameter for texture coordinate r to either
?GL_CLAMP_TO_EDGE , ?GL_MIRRORED_REPEAT, or ?GL_REPEAT. See the discussion under
?GL_TEXTURE_WRAP_S . Initially, ?GL_TEXTURE_WRAP_R is set to ?GL_REPEAT.
?GL_TEXTURE_BORDER_COLOR: The data in Params specifies four values that define the
border values that should be used for border texels. If a texel is sampled from the
border of the texture, the values of ?GL_TEXTURE_BORDER_COLOR are interpreted as an
RGBA color to match the texture's internal format and substituted for the non-
existent texel data. If the texture contains depth components, the first component
of ?GL_TEXTURE_BORDER_COLOR is interpreted as a depth value. The initial value is
(0.0, 0.0, 0.0, 0.0).
?GL_TEXTURE_COMPARE_MODE: Specifies the texture comparison mode for currently bound
textures. That is, a texture whose internal format is ?GL_DEPTH_COMPONENT_*; see
gl:texImage2D/9 ) Permissible values are:
?GL_COMPARE_REF_TO_TEXTURE: Specifies that the interpolated and clamped r texture
coordinate should be compared to the value in the currently bound texture. See the
discussion of ?GL_TEXTURE_COMPARE_FUNC for details of how the comparison is
evaluated. The result of the comparison is assigned to the red channel.
?GL_NONE: Specifies that the red channel should be assigned the appropriate value
from the currently bound texture.
?GL_TEXTURE_COMPARE_FUNC: Specifies the comparison operator used when
?GL_TEXTURE_COMPARE_MODE is set to ?GL_COMPARE_REF_TO_TEXTURE. Permissible values
are:Texture Comparison FunctionComputed result
?GL_LEQUAL result={1.0 0.0 r<=(D t) r>(D t))
?GL_GEQUAL result={1.0 0.0 r>=(D t) r<(D t))
?GL_LESS result={1.0 0.0 r<(D t) r>=(D t))
?GL_GREATER result={1.0 0.0 r>(D t) r<=(D t))
?GL_EQUAL result={1.0 0.0 r=(D t) r≠ (D t))
?GL_NOTEQUAL result={1.0 0.0 r≠(D t) r=(D t))
?GL_ALWAYS result=1.0
?GL_NEVER result=0.0
where r is the current interpolated texture coordinate, and D t is the texture
value sampled from the currently bound texture. result is assigned to R t.
See external documentation.
samplerParameteriv(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = [integer()]
See samplerParameteri/3
samplerParameterf(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = float()
See samplerParameteri/3
samplerParameterfv(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = [float()]
See samplerParameteri/3
samplerParameterIiv(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = [integer()]
See samplerParameteri/3
samplerParameterIuiv(Sampler, Pname, Param) -> ok
Types:
Sampler = integer()
Pname = enum()
Param = [integer()]
glSamplerParameterI
See external documentation.
getSamplerParameteriv(Sampler, Pname) -> [integer()]
Types:
Sampler = integer()
Pname = enum()
Return sampler parameter values
gl:getSamplerParameter returns in Params the value or values of the sampler
parameter specified as Pname . Sampler defines the target sampler, and must be the
name of an existing sampler object, returned from a previous call to
gl:genSamplers/1 . Pname accepts the same symbols as gl:samplerParameteri/3 , with
the same interpretations:
?GL_TEXTURE_MAG_FILTER: Returns the single-valued texture magnification filter, a
symbolic constant. The initial value is ?GL_LINEAR.
?GL_TEXTURE_MIN_FILTER: Returns the single-valued texture minification filter, a
symbolic constant. The initial value is ?GL_NEAREST_MIPMAP_LINEAR.
?GL_TEXTURE_MIN_LOD: Returns the single-valued texture minimum level-of-detail
value. The initial value is -1000.
?GL_TEXTURE_MAX_LOD: Returns the single-valued texture maximum level-of-detail
value. The initial value is 1000.
?GL_TEXTURE_WRAP_S: Returns the single-valued wrapping function for texture
coordinate s, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_WRAP_T: Returns the single-valued wrapping function for texture
coordinate t, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_WRAP_R: Returns the single-valued wrapping function for texture
coordinate r, a symbolic constant. The initial value is ?GL_REPEAT.
?GL_TEXTURE_BORDER_COLOR: Returns four integer or floating-point numbers that
comprise the RGBA color of the texture border. Floating-point values are returned
in the range [0 1]. Integer values are returned as a linear mapping of the internal
floating-point representation such that 1.0 maps to the most positive representable
integer and -1.0 maps to the most negative representable integer. The initial value
is (0, 0, 0, 0).
?GL_TEXTURE_COMPARE_MODE: Returns a single-valued texture comparison mode, a
symbolic constant. The initial value is ?GL_NONE. See gl:samplerParameteri/3 .
?GL_TEXTURE_COMPARE_FUNC: Returns a single-valued texture comparison function, a
symbolic constant. The initial value is ?GL_LEQUAL. See gl:samplerParameteri/3 .
See external documentation.
getSamplerParameterIiv(Sampler, Pname) -> [integer()]
Types:
Sampler = integer()
Pname = enum()
See getSamplerParameteriv/2
getSamplerParameterfv(Sampler, Pname) -> [float()]
Types:
Sampler = integer()
Pname = enum()
See getSamplerParameteriv/2
getSamplerParameterIuiv(Sampler, Pname) -> [integer()]
Types:
Sampler = integer()
Pname = enum()
glGetSamplerParameterI
See external documentation.
queryCounter(Id, Target) -> ok
Types:
Id = integer()
Target = enum()
Record the GL time into a query object after all previous commands have reached the
GL server but have not yet necessarily executed.
gl:queryCounter causes the GL to record the current time into the query object
named Id . Target must be ?GL_TIMESTAMP. The time is recorded after all previous
commands on the GL client and server state and the framebuffer have been fully
realized. When the time is recorded, the query result for that object is marked
available. gl:queryCounter timer queries can be used within a gl:beginQuery/2 /
gl:beginQuery/2 block where the target is ?GL_TIME_ELAPSED and it does not affect
the result of that query object.
See external documentation.
getQueryObjecti64v(Id, Pname) -> integer()
Types:
Id = integer()
Pname = enum()
glGetQueryObjecti64v
See external documentation.
getQueryObjectui64v(Id, Pname) -> integer()
Types:
Id = integer()
Pname = enum()
glGetQueryObjectui64v
See external documentation.
drawArraysIndirect(Mode, Indirect) -> ok
Types:
Mode = enum()
Indirect = offset() | mem()
Render primitives from array data, taking parameters from memory
gl:drawArraysIndirect specifies multiple geometric primitives with very few
subroutine calls. gl:drawArraysIndirect behaves similarly to
gl:drawArraysInstancedBaseInstance/5 , execept that the parameters to
gl:drawArraysInstancedBaseInstance/5 are stored in memory at the address given by
Indirect .
The parameters addressed by Indirect are packed into a structure that takes the
form (in C): typedef struct { uint count; uint primCount; uint first; uint
baseInstance; } DrawArraysIndirectCommand; const DrawArraysIndirectCommand *cmd =
(const DrawArraysIndirectCommand *)indirect;
glDrawArraysInstancedBaseInstance(mode, cmd->first, cmd->count, cmd->primCount,
cmd->baseInstance);
If a buffer is bound to the ?GL_DRAW_INDIRECT_BUFFER binding at the time of a call
to gl:drawArraysIndirect, Indirect is interpreted as an offset, in basic machine
units, into that buffer and the parameter data is read from the buffer rather than
from client memory.
In contrast to gl:drawArraysInstancedBaseInstance/5 , the first member of the
parameter structure is unsigned, and out-of-range indices do not generate an error.
Vertex attributes that are modified by gl:drawArraysIndirect have an unspecified
value after gl:drawArraysIndirect returns. Attributes that aren't modified remain
well defined.
See external documentation.
drawElementsIndirect(Mode, Type, Indirect) -> ok
Types:
Mode = enum()
Type = enum()
Indirect = offset() | mem()
Render indexed primitives from array data, taking parameters from memory
gl:drawElementsIndirect specifies multiple indexed geometric primitives with very
few subroutine calls. gl:drawElementsIndirect behaves similarly to
gl:drawElementsInstancedBaseVertexBaseInstance/7 , execpt that the parameters to
gl:drawElementsInstancedBaseVertexBaseInstance/7 are stored in memory at the
address given by Indirect .
The parameters addressed by Indirect are packed into a structure that takes the
form (in C): typedef struct { uint count; uint primCount; uint firstIndex; uint
baseVertex; uint baseInstance; } DrawElementsIndirectCommand;
gl:drawElementsIndirect is equivalent to: void glDrawElementsIndirect(GLenum mode,
GLenum type, const void * indirect) { const DrawElementsIndirectCommand *cmd =
(const DrawElementsIndirectCommand *)indirect;
glDrawElementsInstancedBaseVertexBaseInstance(mode, cmd->count, type,
cmd->firstIndex + size-of-type, cmd->primCount, cmd->baseVertex,
cmd->baseInstance); }
If a buffer is bound to the ?GL_DRAW_INDIRECT_BUFFER binding at the time of a call
to gl:drawElementsIndirect, Indirect is interpreted as an offset, in basic machine
units, into that buffer and the parameter data is read from the buffer rather than
from client memory.
Note that indices stored in client memory are not supported. If no buffer is bound
to the ?GL_ELEMENT_ARRAY_BUFFER binding, an error will be generated.
The results of the operation are undefined if the reservedMustBeZero member of the
parameter structure is non-zero. However, no error is generated in this case.
Vertex attributes that are modified by gl:drawElementsIndirect have an unspecified
value after gl:drawElementsIndirect returns. Attributes that aren't modified remain
well defined.
See external documentation.
uniform1d(Location, X) -> ok
Types:
Location = integer()
X = float()
See uniform1f/2
uniform2d(Location, X, Y) -> ok
Types:
Location = integer()
X = float()
Y = float()
See uniform1f/2
uniform3d(Location, X, Y, Z) -> ok
Types:
Location = integer()
X = float()
Y = float()
Z = float()
See uniform1f/2
uniform4d(Location, X, Y, Z, W) -> ok
Types:
Location = integer()
X = float()
Y = float()
Z = float()
W = float()
See uniform1f/2
uniform1dv(Location, Value) -> ok
Types:
Location = integer()
Value = [float()]
See uniform1f/2
uniform2dv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float()}]
See uniform1f/2
uniform3dv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float(), float()}]
See uniform1f/2
uniform4dv(Location, Value) -> ok
Types:
Location = integer()
Value = [{float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix2dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix3dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float()}]
See uniform1f/2
uniformMatrix4dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
uniformMatrix2x3dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix2x4dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
uniformMatrix3x2dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix3x4dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See uniform1f/2
uniformMatrix4x2dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See uniform1f/2
uniformMatrix4x3dv(Location, Transpose, Value) -> ok
Types:
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See uniform1f/2
getUniformdv(Program, Location) -> matrix()
Types:
Program = integer()
Location = integer()
See getUniformfv/2
getSubroutineUniformLocation(Program, Shadertype, Name) -> integer()
Types:
Program = integer()
Shadertype = enum()
Name = string()
Retrieve the location of a subroutine uniform of a given shader stage within a
program
gl:getSubroutineUniformLocation returns the location of the subroutine uniform
variable Name in the shader stage of type Shadertype attached to Program , with
behavior otherwise identical to gl:getUniformLocation/2 .
If Name is not the name of a subroutine uniform in the shader stage, -1 is
returned, but no error is generated. If Name is the name of a subroutine uniform in
the shader stage, a value between zero and the value of
?GL_ACTIVE_SUBROUTINE_LOCATIONS minus one will be returned. Subroutine locations
are assigned using consecutive integers in the range from zero to the value of
?GL_ACTIVE_SUBROUTINE_LOCATIONS minus one for the shader stage. For active
subroutine uniforms declared as arrays, the declared array elements are assigned
consecutive locations.
See external documentation.
getSubroutineIndex(Program, Shadertype, Name) -> integer()
Types:
Program = integer()
Shadertype = enum()
Name = string()
Retrieve the index of a subroutine uniform of a given shader stage within a program
gl:getSubroutineIndex returns the index of a subroutine uniform within a shader
stage attached to a program object. Program contains the name of the program to
which the shader is attached. Shadertype specifies the stage from which to query
shader subroutine index. Name contains the null-terminated name of the subroutine
uniform whose name to query.
If Name is not the name of a subroutine uniform in the shader stage,
?GL_INVALID_INDEX is returned, but no error is generated. If Name is the name of a
subroutine uniform in the shader stage, a value between zero and the value of
?GL_ACTIVE_SUBROUTINES minus one will be returned. Subroutine indices are assigned
using consecutive integers in the range from zero to the value of
?GL_ACTIVE_SUBROUTINES minus one for the shader stage.
See external documentation.
getActiveSubroutineUniformName(Program, Shadertype, Index, Bufsize) -> string()
Types:
Program = integer()
Shadertype = enum()
Index = integer()
Bufsize = integer()
Query the name of an active shader subroutine uniform
gl:getActiveSubroutineUniformName retrieves the name of an active shader subroutine
uniform. Program contains the name of the program containing the uniform.
Shadertype specifies the stage for which which the uniform location, given by Index
, is valid. Index must be between zero and the value of
?GL_ACTIVE_SUBROUTINE_UNIFORMS minus one for the shader stage.
The uniform name is returned as a null-terminated string in Name . The actual
number of characters written into Name , excluding the null terminator is returned
in Length . If Length is ?NULL, no length is returned. The maximum number of
characters that may be written into Name , including the null terminator, is
specified by Bufsize . The length of the longest subroutine uniform name in Program
and Shadertype is given by the value of ?GL_ACTIVE_SUBROUTINE_UNIFORM_MAX_LENGTH,
which can be queried with gl:getProgramStageiv/3 .
See external documentation.
getActiveSubroutineName(Program, Shadertype, Index, Bufsize) -> string()
Types:
Program = integer()
Shadertype = enum()
Index = integer()
Bufsize = integer()
Query the name of an active shader subroutine
gl:getActiveSubroutineName queries the name of an active shader subroutine uniform
from the program object given in Program . Index specifies the index of the shader
subroutine uniform within the shader stage given by Stage , and must between zero
and the value of ?GL_ACTIVE_SUBROUTINES minus one for the shader stage.
The name of the selected subroutine is returned as a null-terminated string in Name
. The actual number of characters written into Name , not including the null-
terminator, is is returned in Length . If Length is ?NULL, no length is returned.
The maximum number of characters that may be written into Name , including the
null-terminator, is given in Bufsize .
See external documentation.
uniformSubroutinesuiv(Shadertype, Indices) -> ok
Types:
Shadertype = enum()
Indices = [integer()]
Load active subroutine uniforms
gl:uniformSubroutines loads all active subroutine uniforms for shader stage
Shadertype of the current program with subroutine indices from Indices , storing
Indices[i] into the uniform at location I . Count must be equal to the value of
?GL_ACTIVE_SUBROUTINE_UNIFORM_LOCATIONS for the program currently in use at shader
stage Shadertype . Furthermore, all values in Indices must be less than the value
of ?GL_ACTIVE_SUBROUTINES for the shader stage.
See external documentation.
getUniformSubroutineuiv(Shadertype, Location) -> {integer(), integer(), integer(),
integer(), integer(), integer(), integer(), integer(), integer(), integer(), integer(),
integer(), integer(), integer(), integer(), integer()}
Types:
Shadertype = enum()
Location = integer()
Retrieve the value of a subroutine uniform of a given shader stage of the current
program
gl:getUniformSubroutine retrieves the value of the subroutine uniform at location
Location for shader stage Shadertype of the current program. Location must be less
than the value of ?GL_ACTIVE_SUBROUTINE_UNIFORM_LOCATIONS for the shader currently
in use at shader stage Shadertype . The value of the subroutine uniform is returned
in Values .
See external documentation.
getProgramStageiv(Program, Shadertype, Pname) -> integer()
Types:
Program = integer()
Shadertype = enum()
Pname = enum()
Retrieve properties of a program object corresponding to a specified shader stage
gl:getProgramStage queries a parameter of a shader stage attached to a program
object. Program contains the name of the program to which the shader is attached.
Shadertype specifies the stage from which to query the parameter. Pname specifies
which parameter should be queried. The value or values of the parameter to be
queried is returned in the variable whose address is given in Values .
If Pname is ?GL_ACTIVE_SUBROUTINE_UNIFORMS, the number of active subroutine
variables in the stage is returned in Values .
If Pname is ?GL_ACTIVE_SUBROUTINE_UNIFORM_LOCATIONS, the number of active
subroutine variable locations in the stage is returned in Values .
If Pname is ?GL_ACTIVE_SUBROUTINES, the number of active subroutines in the stage
is returned in Values .
If Pname is ?GL_ACTIVE_SUBROUTINE_UNIFORM_MAX_LENGTH, the length of the longest
subroutine uniform for the stage is returned in Values .
If Pname is ?GL_ACTIVE_SUBROUTINE_MAX_LENGTH, the length of the longest subroutine
name for the stage is returned in Values . The returned name length includes space
for the null-terminator.
If there is no shader present of type Shadertype , the returned value will be
consistent with a shader containing no subroutines or subroutine uniforms.
See external documentation.
patchParameteri(Pname, Value) -> ok
Types:
Pname = enum()
Value = integer()
Specifies the parameters for patch primitives
gl:patchParameter specifies the parameters that will be used for patch primitives.
Pname specifies the parameter to modify and must be either ?GL_PATCH_VERTICES,
?GL_PATCH_DEFAULT_OUTER_LEVEL or ?GL_PATCH_DEFAULT_INNER_LEVEL. For
gl:patchParameteri, Value specifies the new value for the parameter specified by
Pname . For gl:patchParameterfv, Values specifies the address of an array
containing the new values for the parameter specified by Pname .
When Pname is ?GL_PATCH_VERTICES, Value specifies the number of vertices that will
be used to make up a single patch primitive. Patch primitives are consumed by the
tessellation control shader (if present) and subsequently used for tessellation.
When primitives are specified using gl:drawArrays/3 or a similar function, each
patch will be made from Parameter control points, each represented by a vertex
taken from the enabeld vertex arrays. Parameter must be greater than zero, and less
than or equal to the value of ?GL_MAX_PATCH_VERTICES.
When Pname is ?GL_PATCH_DEFAULT_OUTER_LEVEL or ?GL_PATCH_DEFAULT_INNER_LEVEL ,
Values contains the address of an array contiaining the default outer or inner
tessellation levels, respectively, to be used when no tessellation control shader
is present.
See external documentation.
patchParameterfv(Pname, Values) -> ok
Types:
Pname = enum()
Values = [float()]
See patchParameteri/2
bindTransformFeedback(Target, Id) -> ok
Types:
Target = enum()
Id = integer()
Bind a transform feedback object
gl:bindTransformFeedback binds the transform feedback object with name Id to the
current GL state. Id must be a name previously returned from a call to
gl:genTransformFeedbacks/1 . If Id has not previously been bound, a new transform
feedback object with name Id and initialized with with the default transform state
vector is created.
In the initial state, a default transform feedback object is bound and treated as a
transform feedback object with a name of zero. If the name zero is subsequently
bound, the default transform feedback object is again bound to the GL state.
While a transform feedback buffer object is bound, GL operations on the target to
which it is bound affect the bound transform feedback object, and queries of the
target to which a transform feedback object is bound return state from the bound
object. When buffer objects are bound for transform feedback, they are attached to
the currently bound transform feedback object. Buffer objects are used for trans-
form feedback only if they are attached to the currently bound transform feedback
object.
See external documentation.
deleteTransformFeedbacks(Ids) -> ok
Types:
Ids = [integer()]
Delete transform feedback objects
gl:deleteTransformFeedbacks deletes the N transform feedback objects whose names
are stored in the array Ids . Unused names in Ids are ignored, as is the name zero.
After a transform feedback object is deleted, its name is again unused and it has
no contents. If an active transform feedback object is deleted, its name
immediately becomes unused, but the underlying object is not deleted until it is no
longer active.
See external documentation.
genTransformFeedbacks(N) -> [integer()]
Types:
N = integer()
Reserve transform feedback object names
gl:genTransformFeedbacks returns N previously unused transform feedback object
names in Ids . These names are marked as used, for the purposes of
gl:genTransformFeedbacks only, but they acquire transform feedback state only when
they are first bound.
See external documentation.
isTransformFeedback(Id) -> 0 | 1
Types:
Id = integer()
Determine if a name corresponds to a transform feedback object
gl:isTransformFeedback returns ?GL_TRUE if Id is currently the name of a transform
feedback object. If Id is zero, or if ?id is not the name of a transform feedback
object, or if an error occurs, gl:isTransformFeedback returns ?GL_FALSE. If Id is a
name returned by gl:genTransformFeedbacks/1 , but that has not yet been bound
through a call to gl:bindTransformFeedback/2 , then the name is not a transform
feedback object and gl:isTransformFeedback returns ?GL_FALSE .
See external documentation.
pauseTransformFeedback() -> ok
Pause transform feedback operations
gl:pauseTransformFeedback pauses transform feedback operations on the currently
active transform feedback object. When transform feedback operations are paused,
transform feedback is still considered active and changing most transform feedback
state related to the object results in an error. However, a new transform feedback
object may be bound while transform feedback is paused.
See external documentation.
resumeTransformFeedback() -> ok
Resume transform feedback operations
gl:resumeTransformFeedback resumes transform feedback operations on the currently
active transform feedback object. When transform feedback operations are paused,
transform feedback is still considered active and changing most transform feedback
state related to the object results in an error. However, a new transform feedback
object may be bound while transform feedback is paused.
See external documentation.
drawTransformFeedback(Mode, Id) -> ok
Types:
Mode = enum()
Id = integer()
Render primitives using a count derived from a transform feedback object
gl:drawTransformFeedback draws primitives of a type specified by Mode using a count
retrieved from the transform feedback specified by Id . Calling
gl:drawTransformFeedback is equivalent to calling gl:drawArrays/3 with Mode as
specified, First set to zero, and Count set to the number of vertices captured on
vertex stream zero the last time transform feedback was active on the transform
feedback object named by Id .
See external documentation.
drawTransformFeedbackStream(Mode, Id, Stream) -> ok
Types:
Mode = enum()
Id = integer()
Stream = integer()
Render primitives using a count derived from a specifed stream of a transform
feedback object
gl:drawTransformFeedbackStream draws primitives of a type specified by Mode using a
count retrieved from the transform feedback stream specified by Stream of the
transform feedback object specified by Id . Calling gl:drawTransformFeedbackStream
is equivalent to calling gl:drawArrays/3 with Mode as specified, First set to zero,
and Count set to the number of vertices captured on vertex stream Stream the last
time transform feedback was active on the transform feedback object named by Id .
Calling gl:drawTransformFeedback/2 is equivalent to calling
gl:drawTransformFeedbackStream with Stream set to zero.
See external documentation.
beginQueryIndexed(Target, Index, Id) -> ok
Types:
Target = enum()
Index = integer()
Id = integer()
glBeginQueryIndexe
See external documentation.
endQueryIndexed(Target, Index) -> ok
Types:
Target = enum()
Index = integer()
Delimit the boundaries of a query object on an indexed target
gl:beginQueryIndexed and gl:endQueryIndexed/2 delimit the boundaries of a query
object. Query must be a name previously returned from a call to gl:genQueries/1 .
If a query object with name Id does not yet exist it is created with the type
determined by Target . Target must be one of ?GL_SAMPLES_PASSED,
?GL_ANY_SAMPLES_PASSED , ?GL_PRIMITIVES_GENERATED,
?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, or ?GL_TIME_ELAPSED . The behavior of
the query object depends on its type and is as follows.
Index specifies the index of the query target and must be between a Target
-specific maximum.
If Target is ?GL_SAMPLES_PASSED, Id must be an unused name, or the name of an
existing occlusion query object. When gl:beginQueryIndexed is executed, the query
object's samples-passed counter is reset to 0. Subsequent rendering will increment
the counter for every sample that passes the depth test. If the value of
?GL_SAMPLE_BUFFERS is 0, then the samples-passed count is incremented by 1 for each
fragment. If the value of ?GL_SAMPLE_BUFFERS is 1, then the samples-passed count is
incremented by the number of samples whose coverage bit is set. However,
implementations, at their discression may instead increase the samples-passed count
by the value of ?GL_SAMPLES if any sample in the fragment is covered. When
gl:endQueryIndexed is executed, the samples-passed counter is assigned to the query
object's result value. This value can be queried by calling gl:getQueryObjectiv/2
with Pname ?GL_QUERY_RESULT. When Target is ?GL_SAMPLES_PASSED, Index must be zero.
If Target is ?GL_ANY_SAMPLES_PASSED, Id must be an unused name, or the name of an
existing boolean occlusion query object. When gl:beginQueryIndexed is executed, the
query object's samples-passed flag is reset to ?GL_FALSE. Subsequent rendering
causes the flag to be set to ?GL_TRUE if any sample passes the depth test. When
gl:endQueryIndexed is executed, the samples-passed flag is assigned to the query
object's result value. This value can be queried by calling gl:getQueryObjectiv/2
with Pname ?GL_QUERY_RESULT. When Target is ?GL_ANY_SAMPLES_PASSED , Index must be
zero.
If Target is ?GL_PRIMITIVES_GENERATED, Id must be an unused name, or the name of an
existing primitive query object previously bound to the ?GL_PRIMITIVES_GENERATED
query binding. When gl:beginQueryIndexed is executed, the query object's
primitives-generated counter is reset to 0. Subsequent rendering will increment the
counter once for every vertex that is emitted from the geometry shader to the
stream given by Index , or from the vertex shader if Index is zero and no geometry
shader is present. When gl:endQueryIndexed is executed, the primitives-generated
counter for stream Index is assigned to the query object's result value. This value
can be queried by calling gl:getQueryObjectiv/2 with Pname ?GL_QUERY_RESULT. When
Target is ?GL_PRIMITIVES_GENERATED , Index must be less than the value of
?GL_MAX_VERTEX_STREAMS.
If Target is ?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, Id must be an unused name,
or the name of an existing primitive query object previously bound to the
?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN query binding. When gl:beginQueryIndexed
is executed, the query object's primitives-written counter for the stream specified
by Index is reset to 0. Subsequent rendering will increment the counter once for
every vertex that is written into the bound transform feedback buffer(s) for stream
Index . If transform feedback mode is not activated between the call to
gl:beginQueryIndexed and gl:endQueryIndexed, the counter will not be incremented.
When gl:endQueryIndexed is executed, the primitives-written counter for stream
Index is assigned to the query object's result value. This value can be queried by
calling gl:getQueryObjectiv/2 with Pname ?GL_QUERY_RESULT. When Target is
?GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN , Index must be less than the value of
?GL_MAX_VERTEX_STREAMS.
If Target is ?GL_TIME_ELAPSED, Id must be an unused name, or the name of an
existing timer query object previously bound to the ?GL_TIME_ELAPSED query binding.
When gl:beginQueryIndexed is executed, the query object's time counter is reset to
0. When gl:endQueryIndexed is executed, the elapsed server time that has passed
since the call to gl:beginQueryIndexed is written into the query object's time
counter. This value can be queried by calling gl:getQueryObjectiv/2 with Pname
?GL_QUERY_RESULT. When Target is ?GL_TIME_ELAPSED, Index must be zero.
Querying the ?GL_QUERY_RESULT implicitly flushes the GL pipeline until the
rendering delimited by the query object has completed and the result is available.
?GL_QUERY_RESULT_AVAILABLE can be queried to determine if the result is immediately
available or if the rendering is not yet complete.
See external documentation.
getQueryIndexediv(Target, Index, Pname) -> integer()
Types:
Target = enum()
Index = integer()
Pname = enum()
Return parameters of an indexed query object target
gl:getQueryIndexediv returns in Params a selected parameter of the indexed query
object target specified by Target and Index . Index specifies the index of the
query object target and must be between zero and a target-specific maxiumum.
Pname names a specific query object target parameter. When Pname is
?GL_CURRENT_QUERY , the name of the currently active query for the specified Index
of Target , or zero if no query is active, will be placed in Params . If Pname is
?GL_QUERY_COUNTER_BITS , the implementation-dependent number of bits used to hold
the result of queries for Target is returned in Params .
See external documentation.
releaseShaderCompiler() -> ok
Release resources consumed by the implementation's shader compiler
gl:releaseShaderCompiler provides a hint to the implementation that it may free
internal resources associated with its shader compiler. gl:compileShader/1 may
subsequently be called and the implementation may at that time reallocate resources
previously freed by the call to gl:releaseShaderCompiler.
See external documentation.
shaderBinary(Shaders, Binaryformat, Binary) -> ok
Types:
Shaders = [integer()]
Binaryformat = enum()
Binary = binary()
Load pre-compiled shader binaries
gl:shaderBinary loads pre-compiled shader binary code into the Count shader objects
whose handles are given in Shaders . Binary points to Length bytes of binary shader
code stored in client memory. BinaryFormat specifies the format of the pre-compiled
code.
The binary image contained in Binary will be decoded according to the extension
specification defining the specified BinaryFormat token. OpenGL does not define any
specific binary formats, but it does provide a mechanism to obtain token vaues for
such formats provided by such extensions.
Depending on the types of the shader objects in Shaders , gl:shaderBinary will
individually load binary vertex or fragment shaders, or load an executable binary
that contains an optimized pair of vertex and fragment shaders stored in the same
binary.
See external documentation.
getShaderPrecisionFormat(Shadertype, Precisiontype) -> {Range::{integer(), integer()},
Precision::integer()}
Types:
Shadertype = enum()
Precisiontype = enum()
Retrieve the range and precision for numeric formats supported by the shader
compiler
gl:getShaderPrecisionFormat retrieves the numeric range and precision for the
implementation's representation of quantities in different numeric formats in
specified shader type. ShaderType specifies the type of shader for which the
numeric precision and range is to be retrieved and must be one of ?GL_VERTEX_SHADER
or ?GL_FRAGMENT_SHADER. PrecisionType specifies the numeric format to query and
must be one of ?GL_LOW_FLOAT, ?GL_MEDIUM_FLOAT ?GL_HIGH_FLOAT, ?GL_LOW_INT,
?GL_MEDIUM_INT, or ?GL_HIGH_INT.
Range points to an array of two integers into which the format's numeric range will
be returned. If min and max are the smallest values representable in the format,
then the values returned are defined to be: Range [0] = floor(log2(|min|)) and
Range [1] = floor(log2(|max|)).
Precision specifies the address of an integer into which will be written the log2
value of the number of bits of precision of the format. If the smallest
representable value greater than 1 is 1 + eps, then the integer addressed by
Precision will contain floor(-log2(eps)).
See external documentation.
depthRangef(N, F) -> ok
Types:
N = clamp()
F = clamp()
See depthRange/2
clearDepthf(D) -> ok
Types:
D = clamp()
glClearDepthf
See external documentation.
getProgramBinary(Program, BufSize) -> {BinaryFormat::enum(), Binary::binary()}
Types:
Program = integer()
BufSize = integer()
Return a binary representation of a program object's compiled and linked executable
source
gl:getProgramBinary returns a binary representation of the compiled and linked
executable for Program into the array of bytes whose address is specified in Binary
. The maximum number of bytes that may be written into Binary is specified by
BufSize . If the program binary is greater in size than BufSize bytes, then an
error is generated, otherwise the actual number of bytes written into Binary is
returned in the variable whose address is given by Length . If Length is ?NULL,
then no length is returned.
The format of the program binary written into Binary is returned in the variable
whose address is given by BinaryFormat , and may be implementation dependent. The
binary produced by the GL may subsequently be returned to the GL by calling
gl:programBinary/3 , with BinaryFormat and Length set to the values returned by
gl:getProgramBinary , and passing the returned binary data in the Binary parameter.
See external documentation.
programBinary(Program, BinaryFormat, Binary) -> ok
Types:
Program = integer()
BinaryFormat = enum()
Binary = binary()
Load a program object with a program binary
gl:programBinary loads a program object with a program binary previously returned
from gl:getProgramBinary/2 . BinaryFormat and Binary must be those returned by a
previous call to gl:getProgramBinary/2 , and Length must be the length returned by
gl:getProgramBinary/2 , or by gl:getProgramiv/2 when called with Pname set to
?GL_PROGRAM_BINARY_LENGTH. If these conditions are not met, loading the program
binary will fail and Program 's ?GL_LINK_STATUS will be set to ?GL_FALSE.
A program object's program binary is replaced by calls to gl:linkProgram/1 or
gl:programBinary . When linking success or failure is concerned, gl:programBinary
can be considered to perform an implicit linking operation. gl:linkProgram/1 and
gl:programBinary both set the program object's ?GL_LINK_STATUS to ?GL_TRUE or
?GL_FALSE .
A successful call to gl:programBinary will reset all uniform variables to their
initial values. The initial value is either the value of the variable's initializer
as specified in the original shader source, or zero if no initializer was present.
Additionally, all vertex shader input and fragment shader output assignments that
were in effect when the program was linked before saving are restored with
gl:programBinary is called.
See external documentation.
programParameteri(Program, Pname, Value) -> ok
Types:
Program = integer()
Pname = enum()
Value = integer()
Specify a parameter for a program object
gl:programParameter specifies a new value for the parameter nameed by Pname for the
program object Program .
If Pname is ?GL_PROGRAM_BINARY_RETRIEVABLE_HINT, Value should be ?GL_FALSE or
?GL_TRUE to indicate to the implementation the intention of the application to
retrieve the program's binary representation with gl:getProgramBinary/2 . The
implementation may use this information to store information that may be useful for
a future query of the program's binary. It is recommended to set
?GL_PROGRAM_BINARY_RETRIEVABLE_HINT for the program to ?GL_TRUE before calling
gl:linkProgram/1 , and using the program at run-time if the binary is to be
retrieved later.
If Pname is ?GL_PROGRAM_SEPARABLE, Value must be ?GL_TRUE or ?GL_FALSE and
indicates whether Program can be bound to individual pipeline stages via
gl:useProgramStages/3 . A program's ?GL_PROGRAM_SEPARABLE parameter must be set to
?GL_TRUEbefore gl:linkProgram/1 is called in order for it to be usable with a
program pipeline object. The initial state of ?GL_PROGRAM_SEPARABLE is ?GL_FALSE.
See external documentation.
useProgramStages(Pipeline, Stages, Program) -> ok
Types:
Pipeline = integer()
Stages = integer()
Program = integer()
Bind stages of a program object to a program pipeline
gl:useProgramStages binds executables from a program object associated with a
specified set of shader stages to the program pipeline object given by Pipeline .
Pipeline specifies the program pipeline object to which to bind the executables.
Stages contains a logical combination of bits indicating the shader stages to use
within Program with the program pipeline object Pipeline . Stages must be a logical
combination of ?GL_VERTEX_SHADER_BIT, ?GL_TESS_CONTROL_SHADER_BIT,
?GL_TESS_EVALUATION_SHADER_BIT , ?GL_GEOMETRY_SHADER_BIT, and
?GL_FRAGMENT_SHADER_BIT. Additionally, the special value ?GL_ALL_SHADER_BITS may be
specified to indicate that all executables contained in Program should be installed
in Pipeline .
If Program refers to a program object with a valid shader attached for an indicated
shader stage, gl:useProgramStages installs the executable code for that stage in
the indicated program pipeline object Pipeline . If Program is zero, or refers to a
program object with no valid shader executable for a given stage, it is as if the
pipeline object has no programmable stage configured for the indicated shader
stages. If Stages contains bits other than those listed above, and is not equal to
?GL_ALL_SHADER_BITS , an error is generated.
See external documentation.
activeShaderProgram(Pipeline, Program) -> ok
Types:
Pipeline = integer()
Program = integer()
Set the active program object for a program pipeline object
gl:activeShaderProgram sets the linked program named by Program to be the active
program for the program pipeline object Pipeline . The active program in the active
program pipeline object is the target of calls to gl:uniform1f/2 when no program
has been made current through a call to gl:useProgram/1 .
See external documentation.
createShaderProgramv(Type, Strings) -> integer()
Types:
Type = enum()
Strings = [string()]
glCreateShaderProgramv
See external documentation.
bindProgramPipeline(Pipeline) -> ok
Types:
Pipeline = integer()
Bind a program pipeline to the current context
gl:bindProgramPipeline binds a program pipeline object to the current context.
Pipeline must be a name previously returned from a call to gl:genProgramPipelines/1
. If no program pipeline exists with name Pipeline then a new pipeline object is
created with that name and initialized to the default state vector.
When a program pipeline object is bound using gl:bindProgramPipeline, any previous
binding is broken and is replaced with a binding to the specified pipeline object.
If Pipeline is zero, the previous binding is broken and is not replaced, leaving no
pipeline object bound. If no current program object has been established by
gl:useProgram/1 , the program objects used for each stage and for uniform updates
are taken from the bound program pipeline object, if any. If there is a current
program object established by gl:useProgram/1 , the bound program pipeline object
has no effect on rendering or uniform updates. When a bound program pipeline object
is used for rendering, individual shader executables are taken from its program
objects.
See external documentation.
deleteProgramPipelines(Pipelines) -> ok
Types:
Pipelines = [integer()]
Delete program pipeline objects
gl:deleteProgramPipelines deletes the N program pipeline objects whose names are
stored in the array Pipelines . Unused names in Pipelines are ignored, as is the
name zero. After a program pipeline object is deleted, its name is again unused and
it has no contents. If program pipeline object that is currently bound is deleted,
the binding for that object reverts to zero and no program pipeline object becomes
current.
See external documentation.
genProgramPipelines(N) -> [integer()]
Types:
N = integer()
Reserve program pipeline object names
gl:genProgramPipelines returns N previously unused program pipeline object names in
Pipelines . These names are marked as used, for the purposes of
gl:genProgramPipelines only, but they acquire program pipeline state only when they
are first bound.
See external documentation.
isProgramPipeline(Pipeline) -> 0 | 1
Types:
Pipeline = integer()
Determine if a name corresponds to a program pipeline object
gl:isProgramPipeline returns ?GL_TRUE if Pipeline is currently the name of a
program pipeline object. If Pipeline is zero, or if ?pipeline is not the name of a
program pipeline object, or if an error occurs, gl:isProgramPipeline returns
?GL_FALSE. If Pipeline is a name returned by gl:genProgramPipelines/1 , but that
has not yet been bound through a call to gl:bindProgramPipeline/1 , then the name
is not a program pipeline object and gl:isProgramPipeline returns ?GL_FALSE .
See external documentation.
getProgramPipelineiv(Pipeline, Pname) -> integer()
Types:
Pipeline = integer()
Pname = enum()
Retrieve properties of a program pipeline object
gl:getProgramPipelineiv retrieves the value of a property of the program pipeline
object Pipeline . Pname specifies the name of the parameter whose value to
retrieve. The value of the parameter is written to the variable whose address is
given by Params .
If Pname is ?GL_ACTIVE_PROGRAM, the name of the active program object of the
program pipeline object is returned in Params .
If Pname is ?GL_VERTEX_SHADER, the name of the current program object for the
vertex shader type of the program pipeline object is returned in Params .
If Pname is ?GL_TESS_CONTROL_SHADER, the name of the current program object for the
tessellation control shader type of the program pipeline object is returned in
Params .
If Pname is ?GL_TESS_EVALUATION_SHADER, the name of the current program object for
the tessellation evaluation shader type of the program pipeline object is returned
in Params .
If Pname is ?GL_GEOMETRY_SHADER, the name of the current program object for the
geometry shader type of the program pipeline object is returned in Params .
If Pname is ?GL_FRAGMENT_SHADER, the name of the current program object for the
fragment shader type of the program pipeline object is returned in Params .
If Pname is ?GL_INFO_LOG_LENGTH, the length of the info log, including the null
terminator, is returned in Params . If there is no info log, zero is returned.
See external documentation.
programUniform1i(Program, Location, V0) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
Specify the value of a uniform variable for a specified program object
gl:programUniform modifies the value of a uniform variable or a uniform variable
array. The location of the uniform variable to be modified is specified by Location
, which should be a value returned by gl:getUniformLocation/2 . gl:programUniform
operates on the program object specified by Program .
The commands gl:programUniform{1|2|3|4}{f|i|ui} are used to change the value of the
uniform variable specified by Location using the values passed as arguments. The
number specified in the command should match the number of components in the data
type of the specified uniform variable (e.g., 1 for float, int, unsigned int, bool;
2 for vec2, ivec2, uvec2, bvec2, etc.). The suffix f indicates that floating-point
values are being passed; the suffix i indicates that integer values are being
passed; the suffix ui indicates that unsigned integer values are being passed, and
this type should also match the data type of the specified uniform variable. The i
variants of this function should be used to provide values for uniform variables
defined as int, ivec2 , ivec3, ivec4, or arrays of these. The ui variants of this
function should be used to provide values for uniform variables defined as unsigned
int, uvec2, uvec3, uvec4, or arrays of these. The f variants should be used to
provide values for uniform variables of type float, vec2, vec3, vec4, or arrays of
these. Either the i, ui or f variants may be used to provide values for uniform
variables of type bool, bvec2 , bvec3, bvec4, or arrays of these. The uniform
variable will be set to false if the input value is 0 or 0.0f, and it will be set
to true otherwise.
All active uniform variables defined in a program object are initialized to 0 when
the program object is linked successfully. They retain the values assigned to them
by a call to gl:programUniform until the next successful link operation occurs on
the program object, when they are once again initialized to 0.
The commands gl:programUniform{1|2|3|4}{f|i|ui}v can be used to modify a single
uniform variable or a uniform variable array. These commands pass a count and a
pointer to the values to be loaded into a uniform variable or a uniform variable
array. A count of 1 should be used if modifying the value of a single uniform
variable, and a count of 1 or greater can be used to modify an entire array or part
of an array. When loading n elements starting at an arbitrary position m in a
uniform variable array, elements m + n - 1 in the array will be replaced with the
new values. If M + N - 1 is larger than the size of the uniform variable array,
values for all array elements beyond the end of the array will be ignored. The
number specified in the name of the command indicates the number of components for
each element in Value , and it should match the number of components in the data
type of the specified uniform variable (e.g., 1 for float, int, bool; 2 for vec2,
ivec2, bvec2, etc.). The data type specified in the name of the command must match
the data type for the specified uniform variable as described previously for
gl:programUniform{1|2|3|4}{f|i|ui}.
For uniform variable arrays, each element of the array is considered to be of the
type indicated in the name of the command (e.g., gl:programUniform3f or
gl:programUniform3fv can be used to load a uniform variable array of type vec3).
The number of elements of the uniform variable array to be modified is specified by
Count
The commands gl:programUniformMatrix{2|3|4|2x3|3x2|2x4|4x2|3x4|4x3}fv are used to
modify a matrix or an array of matrices. The numbers in the command name are
interpreted as the dimensionality of the matrix. The number 2 indicates a 2 × 2
matrix (i.e., 4 values), the number 3 indicates a 3 × 3 matrix (i.e., 9 values),
and the number 4 indicates a 4 × 4 matrix (i.e., 16 values). Non-square matrix
dimensionality is explicit, with the first number representing the number of
columns and the second number representing the number of rows. For example, 2x4
indicates a 2 × 4 matrix with 2 columns and 4 rows (i.e., 8 values). If Transpose
is ?GL_FALSE, each matrix is assumed to be supplied in column major order. If
Transpose is ?GL_TRUE, each matrix is assumed to be supplied in row major order.
The Count argument indicates the number of matrices to be passed. A count of 1
should be used if modifying the value of a single matrix, and a count greater than
1 can be used to modify an array of matrices.
See external documentation.
programUniform1iv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [integer()]
See programUniform1i/3
programUniform1f(Program, Location, V0) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
See programUniform1i/3
programUniform1fv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [float()]
See programUniform1i/3
programUniform1d(Program, Location, V0) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
See programUniform1i/3
programUniform1dv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [float()]
See programUniform1i/3
programUniform1ui(Program, Location, V0) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
See programUniform1i/3
programUniform1uiv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [integer()]
See programUniform1i/3
programUniform2i(Program, Location, V0, V1) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
See programUniform1i/3
programUniform2iv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer()}]
See programUniform1i/3
programUniform2f(Program, Location, V0, V1) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
See programUniform1i/3
programUniform2fv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float()}]
See programUniform1i/3
programUniform2d(Program, Location, V0, V1) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
See programUniform1i/3
programUniform2dv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float()}]
See programUniform1i/3
programUniform2ui(Program, Location, V0, V1) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
See programUniform1i/3
programUniform2uiv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer()}]
See programUniform1i/3
programUniform3i(Program, Location, V0, V1, V2) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
See programUniform1i/3
programUniform3iv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer(), integer()}]
See programUniform1i/3
programUniform3f(Program, Location, V0, V1, V2) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
V2 = float()
See programUniform1i/3
programUniform3fv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float(), float()}]
See programUniform1i/3
programUniform3d(Program, Location, V0, V1, V2) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
V2 = float()
See programUniform1i/3
programUniform3dv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float(), float()}]
See programUniform1i/3
programUniform3ui(Program, Location, V0, V1, V2) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
See programUniform1i/3
programUniform3uiv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer(), integer()}]
See programUniform1i/3
programUniform4i(Program, Location, V0, V1, V2, V3) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
V3 = integer()
See programUniform1i/3
programUniform4iv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer(), integer(), integer()}]
See programUniform1i/3
programUniform4f(Program, Location, V0, V1, V2, V3) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
V2 = float()
V3 = float()
See programUniform1i/3
programUniform4fv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float(), float(), float()}]
See programUniform1i/3
programUniform4d(Program, Location, V0, V1, V2, V3) -> ok
Types:
Program = integer()
Location = integer()
V0 = float()
V1 = float()
V2 = float()
V3 = float()
See programUniform1i/3
programUniform4dv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{float(), float(), float(), float()}]
See programUniform1i/3
programUniform4ui(Program, Location, V0, V1, V2, V3) -> ok
Types:
Program = integer()
Location = integer()
V0 = integer()
V1 = integer()
V2 = integer()
V3 = integer()
See programUniform1i/3
programUniform4uiv(Program, Location, Value) -> ok
Types:
Program = integer()
Location = integer()
Value = [{integer(), integer(), integer(), integer()}]
See programUniform1i/3
programUniformMatrix2fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix3fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float()}]
See programUniform1i/3
programUniformMatrix4fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix2dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix3dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float()}]
See programUniform1i/3
programUniformMatrix4dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix2x3fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix3x2fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix2x4fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix4x2fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix3x4fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix4x3fv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix2x3dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix3x2dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix2x4dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix4x2dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float()}]
See programUniform1i/3
programUniformMatrix3x4dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See programUniform1i/3
programUniformMatrix4x3dv(Program, Location, Transpose, Value) -> ok
Types:
Program = integer()
Location = integer()
Transpose = 0 | 1
Value = [{float(), float(), float(), float(), float(), float(), float(),
float(), float(), float(), float(), float()}]
See programUniform1i/3
validateProgramPipeline(Pipeline) -> ok
Types:
Pipeline = integer()
Validate a program pipeline object against current GL state
gl:validateProgramPipeline instructs the implementation to validate the shader
executables contained in Pipeline against the current GL state. The implementation
may use this as an opportunity to perform any internal shader modifications that
may be required to ensure correct operation of the installed shaders given the
current GL state.
After a program pipeline has been validated, its validation status is set to
?GL_TRUE . The validation status of a program pipeline object may be queried by
calling gl:getProgramPipelineiv/2 with parameter ?GL_VALIDATE_STATUS.
If Pipeline is a name previously returned from a call to gl:genProgramPipelines/1
but that has not yet been bound by a call to gl:bindProgramPipeline/1 , a new
program pipeline object is created with name Pipeline and the default state vector.
See external documentation.
getProgramPipelineInfoLog(Pipeline, BufSize) -> string()
Types:
Pipeline = integer()
BufSize = integer()
Retrieve the info log string from a program pipeline object
gl:getProgramPipelineInfoLog retrieves the info log for the program pipeline object
Pipeline . The info log, including its null terminator, is written into the array
of characters whose address is given by InfoLog . The maximum number of characters
that may be written into InfoLog is given by BufSize , and the actual number of
characters written into InfoLog is returned in the integer whose address is given
by Length . If Length is ?NULL, no length is returned.
The actual length of the info log for the program pipeline may be determined by
calling gl:getProgramPipelineiv/2 with Pname set to ?GL_INFO_LOG_LENGTH.
See external documentation.
vertexAttribL1d(Index, X) -> ok
Types:
Index = integer()
X = float()
glVertexAttribL
See external documentation.
vertexAttribL2d(Index, X, Y) -> ok
Types:
Index = integer()
X = float()
Y = float()
glVertexAttribL
See external documentation.
vertexAttribL3d(Index, X, Y, Z) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
glVertexAttribL
See external documentation.
vertexAttribL4d(Index, X, Y, Z, W) -> ok
Types:
Index = integer()
X = float()
Y = float()
Z = float()
W = float()
glVertexAttribL
See external documentation.
vertexAttribL1dv(Index::integer(), V) -> ok
Types:
V = {X::float()}
Equivalent to vertexAttribL1d(Index, X).
vertexAttribL2dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float()}
Equivalent to vertexAttribL2d(Index, X, Y).
vertexAttribL3dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float()}
Equivalent to vertexAttribL3d(Index, X, Y, Z).
vertexAttribL4dv(Index::integer(), V) -> ok
Types:
V = {X::float(), Y::float(), Z::float(), W::float()}
Equivalent to vertexAttribL4d(Index, X, Y, Z, W).
vertexAttribLPointer(Index, Size, Type, Stride, Pointer) -> ok
Types:
Index = integer()
Size = integer()
Type = enum()
Stride = integer()
Pointer = offset() | mem()
glVertexAttribLPointer
See external documentation.
getVertexAttribLdv(Index, Pname) -> {float(), float(), float(), float()}
Types:
Index = integer()
Pname = enum()
glGetVertexAttribL
See external documentation.
viewportArrayv(First, V) -> ok
Types:
First = integer()
V = [{float(), float(), float(), float()}]
glViewportArrayv
See external documentation.
viewportIndexedf(Index, X, Y, W, H) -> ok
Types:
Index = integer()
X = float()
Y = float()
W = float()
H = float()
Set a specified viewport
gl:viewportIndexedf and gl:viewportIndexedfv specify the parameters for a single
viewport. Index specifies the index of the viewport to modify. Index must be less
than the value of ?GL_MAX_VIEWPORTS. For gl:viewportIndexedf, X , Y , W , and H
specify the left, bottom, width and height of the viewport in pixels, respectively.
For gl:viewportIndexedfv, V contains the address of an array of floating point
values specifying the left ( x), bottom ( y), width ( w), and height ( h) of each
viewport, in that order. x and y give the location of the viewport's lower left
corner, and w and h give the width and height of the viewport, respectively. The
viewport specifies the affine transformation of x and y from normalized device
coordinates to window coordinates. Let (x nd y nd) be normalized device
coordinates. Then the window coordinates (x w y w) are computed as follows:
x w=(x nd+1) (width/2)+x
y w=(y nd+1) (height/2)+y
The location of the viewport's bottom left corner, given by ( x, y) is clamped to
be within the implementaiton-dependent viewport bounds range. The viewport bounds
range [ min, max] can be determined by calling gl:getBooleanv/1 with argument
?GL_VIEWPORT_BOUNDS_RANGE . Viewport width and height are silently clamped to a
range that depends on the implementation. To query this range, call
gl:getBooleanv/1 with argument ?GL_MAX_VIEWPORT_DIMS.
The precision with which the GL interprets the floating point viewport bounds is
implementation-dependent and may be determined by querying the impementation-
defined constant ?GL_VIEWPORT_SUBPIXEL_BITS .
Calling gl:viewportIndexedfv is equivalent to calling see glViewportArray with
First set to Index , Count set to 1 and V passsed directly. gl:viewportIndexedf is
equivalent to: void glViewportIndexedf(GLuint index, GLfloat x, GLfloat y, GLfloat
w, GLfloat h) { const float v[4] = { x, y, w, h }; glViewportArrayv(index, 1, v); }
See external documentation.
viewportIndexedfv(Index, V) -> ok
Types:
Index = integer()
V = {float(), float(), float(), float()}
See viewportIndexedf/5
scissorArrayv(First, V) -> ok
Types:
First = integer()
V = [{integer(), integer(), integer(), integer()}]
glScissorArrayv
See external documentation.
scissorIndexed(Index, Left, Bottom, Width, Height) -> ok
Types:
Index = integer()
Left = integer()
Bottom = integer()
Width = integer()
Height = integer()
glScissorIndexe
See external documentation.
scissorIndexedv(Index, V) -> ok
Types:
Index = integer()
V = {integer(), integer(), integer(), integer()}
glScissorIndexe
See external documentation.
depthRangeArrayv(First, V) -> ok
Types:
First = integer()
V = [{clamp(), clamp()}]
glDepthRangeArrayv
See external documentation.
depthRangeIndexed(Index, N, F) -> ok
Types:
Index = integer()
N = clamp()
F = clamp()
glDepthRangeIndexe
See external documentation.
getFloati_v(Target, Index) -> [float()]
Types:
Target = enum()
Index = integer()
See getBooleanv/1
getDoublei_v(Target, Index) -> [float()]
Types:
Target = enum()
Index = integer()
See getBooleanv/1
debugMessageControlARB(Source, Type, Severity, Ids, Enabled) -> ok
Types:
Source = enum()
Type = enum()
Severity = enum()
Ids = [integer()]
Enabled = 0 | 1
glDebugMessageControlARB
See external documentation.
debugMessageInsertARB(Source, Type, Id, Severity, Buf) -> ok
Types:
Source = enum()
Type = enum()
Id = integer()
Severity = enum()
Buf = string()
glDebugMessageInsertARB
See external documentation.
getDebugMessageLogARB(Count, Bufsize) -> {integer(), Sources::[enum()], Types::[enum()],
Ids::[integer()], Severities::[enum()], MessageLog::[string()]}
Types:
Count = integer()
Bufsize = integer()
glGetDebugMessageLogARB
See external documentation.
getGraphicsResetStatusARB() -> enum()
glGetGraphicsResetStatusARB
See external documentation.
drawArraysInstancedBaseInstance(Mode, First, Count, Primcount, Baseinstance) -> ok
Types:
Mode = enum()
First = integer()
Count = integer()
Primcount = integer()
Baseinstance = integer()
Draw multiple instances of a range of elements with offset applied to instanced
attributes
gl:drawArraysInstancedBaseInstance behaves identically to gl:drawArrays/3 except
that Primcount instances of the range of elements are executed and the value of the
internal counter InstanceID advances for each iteration. InstanceID is an internal
32-bit integer counter that may be read by a vertex shader as ?gl_InstanceID .
gl:drawArraysInstancedBaseInstance has the same effect as: if ( mode or count is
invalid ) generate appropriate error else { for (int i = 0; i < primcount ; i++) {
instanceID = i; glDrawArrays(mode, first, count); } instanceID = 0; }
Specific vertex attributes may be classified as instanced through the use of
gl:vertexAttribDivisor/2 . Instanced vertex attributes supply per-instance vertex
data to the vertex shader. The index of the vertex fetched from the enabled
instanced vertex attribute arrays is calculated as: |gl_ InstanceID/divisor|+
baseInstance. Note that Baseinstance does not affect the shader-visible value of
?gl_InstanceID.
See external documentation.
drawElementsInstancedBaseInstance(Mode, Count, Type, Indices, Primcount, Baseinstance) ->
ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Primcount = integer()
Baseinstance = integer()
Draw multiple instances of a set of elements with offset applied to instanced
attributes
gl:drawElementsInstancedBaseInstance behaves identically to gl:drawElements/4
except that Primcount instances of the set of elements are executed and the value
of the internal counter InstanceID advances for each iteration. InstanceID is an
internal 32-bit integer counter that may be read by a vertex shader as
?gl_InstanceID .
gl:drawElementsInstancedBaseInstance has the same effect as: if (mode, count, or
type is invalid ) generate appropriate error else { for (int i = 0; i < primcount ;
i++) { instanceID = i; glDrawElements(mode, count, type, indices); } instanceID =
0; }
Specific vertex attributes may be classified as instanced through the use of
gl:vertexAttribDivisor/2 . Instanced vertex attributes supply per-instance vertex
data to the vertex shader. The index of the vertex fetched from the enabled
instanced vertex attribute arrays is calculated as |gl_ InstanceID/divisor|+
baseInstance. Note that Baseinstance does not affect the shader-visible value of
?gl_InstanceID.
See external documentation.
drawElementsInstancedBaseVertexBaseInstance(Mode, Count, Type, Indices, Primcount,
Basevertex, Baseinstance) -> ok
Types:
Mode = enum()
Count = integer()
Type = enum()
Indices = offset() | mem()
Primcount = integer()
Basevertex = integer()
Baseinstance = integer()
Render multiple instances of a set of primitives from array data with a per-element
offset
gl:drawElementsInstancedBaseVertexBaseInstance behaves identically to
gl:drawElementsInstanced/5 except that the ith element transferred by the
corresponding draw call will be taken from element Indices [i] + Basevertex of each
enabled array. If the resulting value is larger than the maximum value
representable by Type , it is as if the calculation were upconverted to 32-bit
unsigned integers (with wrapping on overflow conditions). The operation is
undefined if the sum would be negative. The Basevertex has no effect on the shader-
visible value of ?gl_VertexID.
Specific vertex attributes may be classified as instanced through the use of
gl:vertexAttribDivisor/2 . Instanced vertex attributes supply per-instance vertex
data to the vertex shader. The index of the vertex fetched from the enabled
instanced vertex attribute arrays is calculated as |gl_ InstanceID/divisor|+
baseInstance. Note that Baseinstance does not affect the shader-visible value of
?gl_InstanceID.
See external documentation.
drawTransformFeedbackInstanced(Mode, Id, Primcount) -> ok
Types:
Mode = enum()
Id = integer()
Primcount = integer()
glDrawTransformFeedbackInstance
See external documentation.
drawTransformFeedbackStreamInstanced(Mode, Id, Stream, Primcount) -> ok
Types:
Mode = enum()
Id = integer()
Stream = integer()
Primcount = integer()
glDrawTransformFeedbackStreamInstance
See external documentation.
getInternalformativ(Target, Internalformat, Pname, BufSize) -> [integer()]
Types:
Target = enum()
Internalformat = enum()
Pname = enum()
BufSize = integer()
glGetInternalformat
See external documentation.
bindImageTexture(Unit, Texture, Level, Layered, Layer, Access, Format) -> ok
Types:
Unit = integer()
Texture = integer()
Level = integer()
Layered = 0 | 1
Layer = integer()
Access = enum()
Format = enum()
Bind a level of a texture to an image unit
gl:bindImageTexture binds a single level of a texture to an image unit for the
purpose of reading and writing it from shaders. Unit specifies the zero-based index
of the image unit to which to bind the texture level. Texture specifies the name of
an existing texture object to bind to the image unit. If Texture is zero, then any
existing binding to the image unit is broken. Level specifies the level of the
texture to bind to the image unit.
If Texture is the name of a one-, two-, or three-dimensional array texture, a cube
map or cube map array texture, or a two-dimensional multisample array texture, then
it is possible to bind either the entire array, or only a single layer of the array
to the image unit. In such cases, if Layered is ?GL_TRUE, the entire array is
attached to the image unit and Layer is ignored. However, if Layered is ?GL_FALSE
then Layer specifies the layer of the array to attach to the image unit.
Access specifies the access types to be performed by shaders and may be set to
?GL_READ_ONLY , ?GL_WRITE_ONLY, or ?GL_READ_WRITE to indicate read-only, write-only
or read-write access, respectively. Violation of the access type specified in
Access (for example, if a shader writes to an image bound with Access set to
?GL_READ_ONLY ) will lead to undefined results, possibly including program
termination.
Format specifies the format that is to be used when performing formatted stores
into the image from shaders. Format must be compatible with the texture's internal
format and must be one of the formats listed in the following table.Image Unit
FormatFormat Qualifier
?GL_RGBA32Frgba32f
?GL_RGBA16F rgba16f
?GL_RG32Frg32f
?GL_RG16F rg16f
?GL_R11F_G11F_B10Fr11f_g11f_b10f
?GL_R32Fr32f
?GL_R16Fr16f
?GL_RGBA32UIrgba32ui
?GL_RGBA16UI rgba16ui
?GL_RGB10_A2UIrgb10_a2ui
?GL_RGBA8UI rgba8ui
?GL_RG32UIrg32ui
?GL_RG16UI rg16ui
?GL_RG8UIrg8ui
?GL_R32UI r32ui
?GL_R16UIr16ui
?GL_R8UI r8ui
?GL_RGBA32Irgba32i
?GL_RGBA16I rgba16i
?GL_RGBA8Irgba8i
?GL_RG32I rg32i
?GL_RG16Irg16i
?GL_RG8I rg8i
?GL_R32Ir32i
?GL_R16I r16i
?GL_R8Ir8i
?GL_RGBA16 rgba16
?GL_RGB10_A2rgb10_a2
?GL_RGBA8 rgba8
?GL_RG16rg16
?GL_RG8 rg8
?GL_R16r16
?GL_R8 r8
?GL_RGBA16_SNORMrgba16_snorm
?GL_RGBA8_SNORM rgba8_snorm
?GL_RG16_SNORMrg16_snorm
?GL_RG8_SNORMrg8_snorm
?GL_R16_SNORMr16_snorm
?GL_R8_SNORMr8_snorm
When a texture is bound to an image unit, the Format parameter for the image unit
need not exactly match the texture internal format as long as the formats are
considered compatible as defined in the OpenGL Specification. The matching
criterion used for a given texture may be determined by calling
gl:getTexParameterfv/2 with Value set to ?GL_IMAGE_FORMAT_COMPATIBILITY_TYPE, with
return values of ?GL_IMAGE_FORMAT_COMPATIBILITY_BY_SIZE and
?GL_IMAGE_FORMAT_COMPATIBILITY_BY_CLASS, specifying matches by size and class,
respectively.
See external documentation.
memoryBarrier(Barriers) -> ok
Types:
Barriers = integer()
Defines a barrier ordering memory transactions
gl:memoryBarrier defines a barrier ordering the memory transactions issued prior to
the command relative to those issued after the barrier. For the purposes of this
ordering, memory transactions performed by shaders are considered to be issued by
the rendering command that triggered the execution of the shader. Barriers is a
bitfield indicating the set of operations that are synchronized with shader stores;
the bits used in Barriers are as follows:
?GL_VERTEX_ATTRIB_ARRAY_BARRIER_BIT: If set, vertex data sourced from buffer
objects after the barrier will reflect data written by shaders prior to the
barrier. The set of buffer objects affected by this bit is derived from the buffer
object bindings used for generic vertex attributes derived from the
?GL_VERTEX_ATTRIB_ARRAY_BUFFER bindings.
?GL_ELEMENT_ARRAY_BARRIER_BIT: If set, vertex array indices sourced from buffer
objects after the barrier will reflect data written by shaders prior to the
barrier. The buffer objects affected by this bit are derived from the
?GL_ELEMENT_ARRAY_BUFFER binding.
?GL_UNIFORM_BARRIER_BIT: Shader uniforms sourced from buffer objects after the
barrier will reflect data written by shaders prior to the barrier.
?GL_TEXTURE_FETCH_BARRIER_BIT: Texture fetches from shaders, including fetches from
buffer object memory via buffer textures, after the barrier will reflect data
written by shaders prior to the barrier.
?GL_SHADER_IMAGE_ACCESS_BARRIER_BIT: Memory accesses using shader image load,
store, and atomic built-in functions issued after the barrier will reflect data
written by shaders prior to the barrier. Additionally, image stores and atomics
issued after the barrier will not execute until all memory accesses (e.g., loads,
stores, texture fetches, vertex fetches) initiated prior to the barrier complete.
?GL_COMMAND_BARRIER_BIT: Command data sourced from buffer objects by Draw*Indirect
commands after the barrier will reflect data written by shaders prior to the
barrier. The buffer objects affected by this bit are derived from the
?GL_DRAW_INDIRECT_BUFFER binding.
?GL_PIXEL_BUFFER_BARRIER_BIT: Reads and writes of buffer objects via the
?GL_PIXEL_PACK_BUFFER and ?GL_PIXEL_UNPACK_BUFFER bindings (via gl:readPixels/7 ,
gl:texSubImage1D/7 , etc.) after the barrier will reflect data written by shaders
prior to the barrier. Additionally, buffer object writes issued after the barrier
will wait on the completion of all shader writes initiated prior to the barrier.
?GL_TEXTURE_UPDATE_BARRIER_BIT: Writes to a texture via gl:tex(Sub)Image*,
gl:copyTex(Sub)Image* , gl:compressedTex(Sub)Image*, and reads via gl:getTexImage/5
after the barrier will reflect data written by shaders prior to the barrier.
Additionally, texture writes from these commands issued after the barrier will not
execute until all shader writes initiated prior to the barrier complete.
?GL_BUFFER_UPDATE_BARRIER_BIT: Reads or writes via gl:bufferSubData/4 ,
gl:copyBufferSubData/5 , or gl:getBufferSubData/4 , or to buffer object memory
mapped by see glMapBuffer or see glMapBufferRange after the barrier will reflect
data written by shaders prior to the barrier. Additionally, writes via these
commands issued after the barrier will wait on the completion of any shader writes
to the same memory initiated prior to the barrier.
?GL_FRAMEBUFFER_BARRIER_BIT: Reads and writes via framebuffer object attachments
after the barrier will reflect data written by shaders prior to the barrier.
Additionally, framebuffer writes issued after the barrier will wait on the
completion of all shader writes issued prior to the barrier.
?GL_TRANSFORM_FEEDBACK_BARRIER_BIT: Writes via transform feedback bindings after
the barrier will reflect data written by shaders prior to the barrier.
Additionally, transform feedback writes issued after the barrier will wait on the
completion of all shader writes issued prior to the barrier.
?GL_ATOMIC_COUNTER_BARRIER_BIT: Accesses to atomic counters after the barrier will
reflect writes prior to the barrier.
If Barriers is ?GL_ALL_BARRIER_BITS, shader memory accesses will be synchronized
relative to all the operations described above.
Implementations may cache buffer object and texture image memory that could be
written by shaders in multiple caches; for example, there may be separate caches
for texture, vertex fetching, and one or more caches for shader memory accesses.
Implementations are not required to keep these caches coherent with shader memory
writes. Stores issued by one invocation may not be immediately observable by other
pipeline stages or other shader invocations because the value stored may remain in
a cache local to the processor executing the store, or because data overwritten by
the store is still in a cache elsewhere in the system. When gl:memoryBarrier is
called, the GL flushes and/or invalidates any caches relevant to the operations
specified by the Barriers parameter to ensure consistent ordering of operations
across the barrier.
To allow for independent shader invocations to communicate by reads and writes to a
common memory address, image variables in the OpenGL Shading Language may be
declared as "coherent". Buffer object or texture image memory accessed through such
variables may be cached only if caches are automatically updated due to stores
issued by any other shader invocation. If the same address is accessed using both
coherent and non-coherent variables, the accesses using variables declared as
coherent will observe the results stored using coherent variables in other
invocations. Using variables declared as "coherent" guarantees only that the
results of stores will be immediately visible to shader invocations using
similarly-declared variables; calling gl:memoryBarrier is required to ensure that
the stores are visible to other operations.
The following guidelines may be helpful in choosing when to use coherent memory
accesses and when to use barriers.
Data that are read-only or constant may be accessed without using coherent
variables or calling MemoryBarrier(). Updates to the read-only data via API calls
such as BufferSubData will invalidate shader caches implicitly as required.
Data that are shared between shader invocations at a fine granularity (e.g.,
written by one invocation, consumed by another invocation) should use coherent
variables to read and write the shared data.
Data written by one shader invocation and consumed by other shader invocations
launched as a result of its execution ("dependent invocations") should use coherent
variables in the producing shader invocation and call memoryBarrier() after the
last write. The consuming shader invocation should also use coherent variables.
Data written to image variables in one rendering pass and read by the shader in a
later pass need not use coherent variables or memoryBarrier(). Calling
MemoryBarrier() with the SHADER_IMAGE_ACCESS_BARRIER_BIT set in Barriers between
passes is necessary.
Data written by the shader in one rendering pass and read by another mechanism
(e.g., vertex or index buffer pulling) in a later pass need not use coherent
variables or memoryBarrier(). Calling gl:memoryBarrier with the appropriate bits
set in Barriers between passes is necessary.
See external documentation.
texStorage1D(Target, Levels, Internalformat, Width) -> ok
Types:
Target = enum()
Levels = integer()
Internalformat = enum()
Width = integer()
Simultaneously specify storage for all levels of a one-dimensional texture
gl:texStorage1D specifies the storage requirements for all levels of a one-
dimensional texture simultaneously. Once a texture is specified with this command,
the format and dimensions of all levels become immutable unless it is a proxy
texture. The contents of the image may still be modified, however, its storage
requirements may not change. Such a texture is referred to as an immutable-format
texture.
Calling gl:texStorage1D is equivalent, assuming no errors are generated, to
executing the following pseudo-code: for (i = 0; i < levels; i++) {
glTexImage1D(target, i, internalformat, width, 0, format, type, NULL); width =
max(1, (width / 2)); }
Since no texture data is actually provided, the values used in the pseudo-code for
Format and Type are irrelevant and may be considered to be any values that are
legal for the chosen Internalformat enumerant. Internalformat must be one of the
sized internal formats given in Table 1 below, one of the sized depth-component
formats ?GL_DEPTH_COMPONENT32F , ?GL_DEPTH_COMPONENT24, or ?GL_DEPTH_COMPONENT16,
or one of the combined depth-stencil formats, ?GL_DEPTH32F_STENCIL8, or
?GL_DEPTH24_STENCIL8. Upon success, the value of ?GL_TEXTURE_IMMUTABLE_FORMAT
becomes ?GL_TRUE. The value of ?GL_TEXTURE_IMMUTABLE_FORMAT may be discovered by
calling gl:getTexParameterfv/2 with Pname set to ?GL_TEXTURE_IMMUTABLE_FORMAT. No
further changes to the dimensions or format of the texture object may be made.
Using any command that might alter the dimensions or format of the texture object
(such as gl:texImage1D/8 or another call to gl:texStorage1D) will result in the
generation of a ?GL_INVALID_OPERATION error, even if it would not, in fact, alter
the dimensions or format of the object.
See external documentation.
texStorage2D(Target, Levels, Internalformat, Width, Height) -> ok
Types:
Target = enum()
Levels = integer()
Internalformat = enum()
Width = integer()
Height = integer()
Simultaneously specify storage for all levels of a two-dimensional or one-
dimensional array texture
gl:texStorage2D specifies the storage requirements for all levels of a two-
dimensional texture or one-dimensional texture array simultaneously. Once a texture
is specified with this command, the format and dimensions of all levels become
immutable unless it is a proxy texture. The contents of the image may still be
modified, however, its storage requirements may not change. Such a texture is
referred to as an immutable-format texture.
The behavior of gl:texStorage2D depends on the Target parameter. When Target is
?GL_TEXTURE_2D, ?GL_PROXY_TEXTURE_2D, ?GL_TEXTURE_RECTANGLE,
?GL_PROXY_TEXTURE_RECTANGLE or ?GL_PROXY_TEXTURE_CUBE_MAP, calling gl:texStorage2D
is equivalent, assuming no errors are generated, to executing the following pseudo-
code: for (i = 0; i < levels; i++) { glTexImage2D(target, i, internalformat, width,
height, 0, format, type, NULL); width = max(1, (width / 2)); height = max(1,
(height / 2)); }
When Target is ?GL_TEXTURE_CUBE_MAP, gl:texStorage2D is equivalent to: for (i = 0;
i < levels; i++) { for (face in (+X, -X, +Y, -Y, +Z, -Z)) { glTexImage2D(face, i,
internalformat, width, height, 0, format, type, NULL); } width = max(1, (width /
2)); height = max(1, (height / 2)); }
When Target is ?GL_TEXTURE_1D or ?GL_TEXTURE_1D_ARRAY, gl:texStorage2D is
equivalent to: for (i = 0; i < levels; i++) { glTexImage2D(target, i,
internalformat, width, height, 0, format, type, NULL); width = max(1, (width / 2));
}
Since no texture data is actually provided, the values used in the pseudo-code for
Format and Type are irrelevant and may be considered to be any values that are
legal for the chosen Internalformat enumerant. Internalformat must be one of the
sized internal formats given in Table 1 below, one of the sized depth-component
formats ?GL_DEPTH_COMPONENT32F , ?GL_DEPTH_COMPONENT24, or ?GL_DEPTH_COMPONENT16,
or one of the combined depth-stencil formats, ?GL_DEPTH32F_STENCIL8, or
?GL_DEPTH24_STENCIL8. Upon success, the value of ?GL_TEXTURE_IMMUTABLE_FORMAT
becomes ?GL_TRUE. The value of ?GL_TEXTURE_IMMUTABLE_FORMAT may be discovered by
calling gl:getTexParameterfv/2 with Pname set to ?GL_TEXTURE_IMMUTABLE_FORMAT. No
further changes to the dimensions or format of the texture object may be made.
Using any command that might alter the dimensions or format of the texture object
(such as gl:texImage2D/9 or another call to gl:texStorage2D) will result in the
generation of a ?GL_INVALID_OPERATION error, even if it would not, in fact, alter
the dimensions or format of the object.
See external documentation.
texStorage3D(Target, Levels, Internalformat, Width, Height, Depth) -> ok
Types:
Target = enum()
Levels = integer()
Internalformat = enum()
Width = integer()
Height = integer()
Depth = integer()
Simultaneously specify storage for all levels of a three-dimensional, two-
dimensional array or cube-map array texture
gl:texStorage3D specifies the storage requirements for all levels of a three-
dimensional, two-dimensional array or cube-map array texture simultaneously. Once a
texture is specified with this command, the format and dimensions of all levels
become immutable unless it is a proxy texture. The contents of the image may still
be modified, however, its storage requirements may not change. Such a texture is
referred to as an immutable-format texture.
The behavior of gl:texStorage3D depends on the Target parameter. When Target is
?GL_TEXTURE_3D, or ?GL_PROXY_TEXTURE_3D, calling gl:texStorage3D is equivalent,
assuming no errors are generated, to executing the following pseudo-code: for (i =
0; i < levels; i++) { glTexImage3D(target, i, internalformat, width, height, depth,
0, format, type, NULL); width = max(1, (width / 2)); height = max(1, (height / 2));
depth = max(1, (depth / 2)); }
When Target is ?GL_TEXTURE_2D_ARRAY, ?GL_PROXY_TEXTURE_2D_ARRAY,
?GL_TEXTURE_CUBE_MAP_ARRAY , or ?GL_PROXY_TEXTURE_CUBE_MAP_ARRAY, gl:texStorage3D
is equivalent to: for (i = 0; i < levels; i++) { glTexImage3D(target, i,
internalformat, width, height, depth, 0, format, type, NULL); width = max(1, (width
/ 2)); height = max(1, (height / 2)); }
Since no texture data is actually provided, the values used in the pseudo-code for
Format and Type are irrelevant and may be considered to be any values that are
legal for the chosen Internalformat enumerant. Internalformat must be one of the
sized internal formats given in Table 1 below, one of the sized depth-component
formats ?GL_DEPTH_COMPONENT32F , ?GL_DEPTH_COMPONENT24, or ?GL_DEPTH_COMPONENT16,
or one of the combined depth-stencil formats, ?GL_DEPTH32F_STENCIL8, or
?GL_DEPTH24_STENCIL8. Upon success, the value of ?GL_TEXTURE_IMMUTABLE_FORMAT
becomes ?GL_TRUE. The value of ?GL_TEXTURE_IMMUTABLE_FORMAT may be discovered by
calling gl:getTexParameterfv/2 with Pname set to ?GL_TEXTURE_IMMUTABLE_FORMAT. No
further changes to the dimensions or format of the texture object may be made.
Using any command that might alter the dimensions or format of the texture object
(such as gl:texImage3D/10 or another call to gl:texStorage3D) will result in the
generation of a ?GL_INVALID_OPERATION error, even if it would not, in fact, alter
the dimensions or format of the object.
See external documentation.
depthBoundsEXT(Zmin, Zmax) -> ok
Types:
Zmin = clamp()
Zmax = clamp()
glDepthBoundsEXT
See external documentation.
stencilClearTagEXT(StencilTagBits, StencilClearTag) -> ok
Types:
StencilTagBits = integer()
StencilClearTag = integer()
glStencilClearTagEXT
See external documentation.
AUTHORS
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wx 1.1.1 gl(3erl)