Hello!! Does anyone know how the glFrustum algorithm works? I don''t seem to get the algorithm right. What i want to do is to convert a vertex (x,y,z) to screen coordinates using the same algorithm as glFrustum uses. And acctually the reverse too - from screen coordinates to a vertex. screenX = MagicGlFrustomAlgorithm( x, y, z ); screenY = MagicGlFrustomAlgorithm( x, y, z ); //Peter - Thanx

Here is the man page for the glFrustum() call that describes how the matrix is setup : http://trant.sgi.com/opengl/docs/man_pages/hardcopy/GL/html/gl/frustum.html

Nate
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