OpenGL.GL.AMD.texture_texture4
OpenGL extension AMD.texture_texture4
This module customises the behaviour of the
OpenGL.raw.GL.AMD.texture_texture4 to provide a more
Python-friendly API
Overview (from the spec)
This extension adds new shading language built-in texture functions
to the shading language.
These texture functions may be used to access one component textures.
The texture4 built-in function returns a texture value derived from
a 2x2 set of texels in the image array of level levelbase is selected.
These texels are selected in the same way as when the value of
TEXTURE_MIN_FILTER is LINEAR, but instead of these texels being
filtered to generate the texture value, the R, G, B and A texture values
are derived directly from these four texels.
The official definition of this extension is available here:
http://www.opengl.org/registry/specs/AMD/texture_texture4.txt