There will never be access to the frame buffer in OpenGL, not in the way you want anyway. This has been discussed at length by nvidia engineers at the opengl.org forums. Ortho mode works quite well anyway.

The fanatic is incorruptible: if he kills for an idea, he can just as well get himself killed for one; in either case, tyrant or martyr, he is a monster.
--EM Cioran

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