Provided by: opengl-4-man-doc_1.0~svn33624-1_all bug

NAME

       glSamplerParameter - set sampler parameters

C SPECIFICATION

       void glSamplerParameterf(GLuint sampler, GLenum pname, GLfloat param);

       void glSamplerParameteri(GLuint sampler, GLenum pname, GLint param);

       void glSamplerParameterfv(GLuint sampler, GLenum pname, const GLfloat * params);

       void glSamplerParameteriv(GLuint sampler, GLenum pname, const GLint * params);

       void glSamplerParameterIiv(GLuint sampler, GLenum pname, const GLint *params);

       void glSamplerParameterIuiv(GLuint sampler, GLenum pname, const GLuint *params);

PARAMETERS

       sampler
           Specifies the sampler object whose parameter to modify.

       pname
           Specifies the symbolic name of a sampler parameter.  pname can be one of the
           following: GL_TEXTURE_WRAP_S, GL_TEXTURE_WRAP_T, GL_TEXTURE_WRAP_R,
           GL_TEXTURE_MIN_FILTER, GL_TEXTURE_MAG_FILTER, GL_TEXTURE_BORDER_COLOR,
           GL_TEXTURE_MIN_LOD, GL_TEXTURE_MAX_LOD, GL_TEXTURE_LOD_BIAS GL_TEXTURE_COMPARE_MODE,
           or GL_TEXTURE_COMPARE_FUNC.

       param
           For the scalar commands, specifies the value of pname.

       params
           For the vector commands (glSamplerParameter*v), specifies a pointer to an array where
           the value or values of pname are stored.

DESCRIPTION

       glSamplerParameter 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 glGenSamplers(). 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 glTexImage1D(), glTexImage2D(), glTexImage3D(),
           glCopyTexImage1D(), or glCopyTexImage2D() 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, GL_REPEAT, or GL_MIRROR_CLAMP_TO_EDGE.  GL_CLAMP_TO_BORDER causes
           the s coordinate to be clamped to the range -1 2N 1 + 1 2N, 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 2N 1 - 1 2N, 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.  GL_MIRROR_CLAMP_TO_EDGE causes the the s coordinate to be
           repeated as for GL_MIRRORED_REPEAT for one reptition of the texture, at which point
           the coordinate to be clamped as in GL_CLAMP_TO_EDGE. 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, GL_REPEAT, or GL_MIRROR_CLAMP_TO_EDGE. 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, GL_REPEAT, or GL_MIRROR_CLAMP_TO_EDGE. 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 glTexImage2D()) 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.

NOTES

       glSamplerParameter is available only if the GL version is 3.3 or higher.

       If a sampler object is bound to a texture unit and that unit is used to sample from a
       texture, the parameters in the sampler are used to sample from the texture, rather than
       the equivalent parameters in the texture object bound to that unit. This introduces the
       possibility of sampling from the same texture object with different sets of sampler state,
       which may lead to a condition where a texture is incomplete with respect to one sampler
       object and not with respect to another. Thus, completeness can be considered a function of
       a sampler object and a texture object bound to a single texture unit, rather than a
       property of the texture object itself.

       GL_MIRROR_CLAMP_TO_EDGE is available only if the GL version is 4.4 or greater.

ERRORS

       GL_INVALID_VALUE is generated if sampler is not the name of a sampler object previously
       returned from a call to glGenSamplers().

       GL_INVALID_ENUM is generated if params should have a defined constant value (based on the
       value of pname) and does not.

ASSOCIATED GETS

       glGetSamplerParameter()

VERSION SUPPORT

       ┌───────────────────────┬───────────────────────────────────────────────────────────────────────┐
       │                       │                OpenGL Version                                         │
       ├───────────────────────┼─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┤
       │Function2.02.13.03.13.23.34.04.14.24.34.44.5 │
       │/                      │     │     │     │     │     │     │     │     │     │     │     │     │
       │Feature                │     │     │     │     │     │     │     │     │     │     │     │     │
       │Name                   │     │     │     │     │     │     │     │     │     │     │     │     │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameterIiv  │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameterIuiv │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameterf    │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameterfv   │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameteri    │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       ├───────────────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glSamplerParameteriv   │  -  │  -  │  -  │  -  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       └───────────────────────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┘

SEE ALSO

       glGenSamplers(), glBindSampler(), glDeleteSamplers(), glIsSampler(), glBindTexture(),
       glTexParameter()

COPYRIGHT

       Copyright © 2010-2014 Khronos Group. This material may be distributed subject to the terms
       and conditions set forth in the Open Publication License, v 1.0, 8 June 1999.
       http://opencontent.org/openpub/.

COPYRIGHT

       Copyright © 2010-2014 KhronosGroup

[FIXME: source]                             01/03/2018                     GLSAMPLERPARAMETER(3G)