NAME

       glCopyTexImage2D - copy pixels into a 2D texture image

C SPECIFICATION

       void glCopyTexImage2D(GLenum target, GLint level, GLenum internalformat, GLint x, GLint y,
                             GLsizei width, GLsizei height, GLint border);

PARAMETERS

       target
           Specifies the target texture. Must be GL_TEXTURE_2D, 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.

       level
           Specifies the level-of-detail number. Level 0 is the base image level. Level n is the
           nth mipmap reduction image.

       internalformat
           Specifies the internal format of the texture. Must be one of the following symbolic
           constants: GL_COMPRESSED_RED, GL_COMPRESSED_RG, GL_COMPRESSED_RGB, GL_COMPRESSED_RGBA.
           GL_COMPRESSED_SRGB, GL_COMPRESSED_SRGB_ALPHA.  GL_DEPTH_COMPONENT,
           GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, GL_DEPTH_COMPONENT32, GL_STENCIL_INDEX8,
           GL_RED, GL_RG, GL_RGB, GL_R3_G3_B2, GL_RGB4, GL_RGB5, GL_RGB8, GL_RGB10, GL_RGB12,
           GL_RGB16, GL_RGBA, GL_RGBA2, GL_RGBA4, GL_RGB5_A1, GL_RGBA8, GL_RGB10_A2, GL_RGBA12,
           GL_RGBA16, GL_SRGB, GL_SRGB8, GL_SRGB_ALPHA, or GL_SRGB8_ALPHA8.

       x, y
           Specify the window coordinates of the lower left corner of the rectangular region of
           pixels to be copied.

       width
           Specifies the width of the texture image.

       height
           Specifies the height of the texture image.

       border
           Must be 0.

DESCRIPTION

       glCopyTexImage2D 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 and a height of height 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 glReadPixels() 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 glPixelMap function can be used
       to accomplish the conversion.

NOTES

       1, 2, 3, and 4 are not accepted values for internalformat.

       An image with height or width of 0 indicates a NULL texture.

       GL_STENCIL_INDEX8 is accepted for internalformat only if the GL version is 4.4 or higher.

ERRORS

       GL_INVALID_ENUM is generated if target is not GL_TEXTURE_2D,
       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.

       GL_INVALID_VALUE is generated if level is less than 0.

       GL_INVALID_VALUE may be generated if level is greater than log 2 ⁢ max, where max is the
       returned value of GL_MAX_TEXTURE_SIZE.

       GL_INVALID_VALUE is generated if width is less than 0 or greater than GL_MAX_TEXTURE_SIZE.

       GL_INVALID_VALUE is generated if border is not 0.

       GL_INVALID_VALUE is generated if internalformat is not an accepted format.

       GL_INVALID_OPERATION is generated if internalformat is GL_DEPTH_COMPONENT,
       GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32 and there is no depth
       buffer.

ASSOCIATED GETS

       glGetTexImage()

SEE ALSO

       glCopyTexImage1D(), glCopyTexSubImage1D(), glCopyTexSubImage2D(), glPixelStore(),
       glTexImage1D(), glTexImage2D(), glTexSubImage1D(), glTexSubImage2D(), glTexParameter()

COPYRIGHT

       Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2012-2013 Khronos Group. This
       document is licensed under the SGI Free Software B License. For details, see
       http://oss.sgi.com/projects/FreeB/.

AUTHORS

       opengl.org