that fixes gamma under GLX. His comments:
* This Linux Quake 2 patch allows to change OpenGL gamma
on the fly without vid_restart. It uses hardware gamma
where available (tested on XFree86 4.2.0 with DRI)
* This is for GLX only, SDL should have its own
implementation, based on its own gamma manipulation
functions
* This is implemented for fullscreen only. I'm not sure
if it shuld be implemented for windowed mode
* I've got the idea from MrG's BeefQuake for Windows, but
the implementation is completely mine
I can confirm that this works beautifully with XFree86
4.1, too.