Hi,

What is the easiest way to calculate the field of view from the projection matrix gl_cpara?

I am trying to draw a scene using gl_cpara as my projection matrix ( I am not switching to 
orthographic). I am displaying my video texture on a polygon which will be display just in front of 
the far plane of my scene. To determine the correct size of the polygon, so my image fill the far 
plane, I need to calculate the field of view from the projection matrix gl_cpara.

I searched the list archive but could not find any clear answer.

Any advice,

Thanks
Alex
-- 
   o Alexandre Gillet               email: gillet@s ..........
  /  The Scripps Research Institute,
o   Dept. Molecular Biology,  MB-5,
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