f = cotangent(fovy/2) dp = near - far f/aspect 0 0 0 0 f 0 0 0 0 (far+near)/dp (2*far*near)/dp 0 0 -1 0Can you instruct me how to calculate inverse of this matrix? I need this in order to transform coordinates back and forth between object space and window space. It is more convenient to use matrix of my own rather than gluProject/glUnProject. Thanks