GLX
GLX (initialism for "OpenGL Extension to the X Window System") is an extension to the X Window System core protocol providing an interface between OpenGL and the X Window System as well as extensions to OpenGL itself. It enables programs wishing to use OpenGL to do so within a window provided by the X Window System. GLX distinguishes two "states": indirect state and direct state.
History
Silicon Graphics developed GLX as part of their effort to support OpenGL in the X Window System. In 1999 SGI released GLX under an open source license, letting it being incorporated in XFree86's source code version 4.0 in 2000. From there, the code was inherited by the forked X.Org Foundation's version of the X Window System X11R6.7.0. On September 19, 2008, SGI created a new SGI FreeB License Version 2.0, which "now mirrors the free X11 license used by X.Org" and "meets the free and open source software community's widely accepted definition of 'free'". In 2009 the Free Software Foundation has endorsed the SGI Free License B to be free software license, and GLX to be an important free software graphics project. As of 2011 GLX has reached version 1.4.
