OpenGL extension SGI.make_current_read
This module customises the behaviour of the OpenGL.raw.GLX.SGI.make_current_read to provide a more Python-friendly API
Overview (from the spec)
The association of the current context with a drawable is extended to allow separate write and read drawables. This paves the way for allowing preprocessing of image data in an "off screen" window which is then read into the visible window for final display. Similarly it sets the frame-work for direct transfer of video to the GL, by treating the video as a special kind of read drawable (a.k.a, readable).
The official definition of this extension is available here: