OpenGL extension ARB.texture_env_crossbar
This module customises the behaviour of the OpenGL.raw.GL.ARB.texture_env_crossbar to provide a more Python-friendly API
Overview (from the spec)
This extension adds the capability to use the texture color from other texture units as sources to the COMBINE_ARB enviornment function. The ARB_texture_env_combine extension defined texture enviornment functions which could use the color from the current texture unit as a source. This extension adds the ability to use the color from any texture unit as a source.
The official definition of this extension is available here:
Return boolean indicating whether this extension is available