glFrustum delete my current matrix
I don't know why, but I use the command glFrustum to increase the far depth of the clipping plane, but I can't see more the object i created..
Here I post the relevant code.. I am now reading the red book, maybe I don't understand something..
please help me..it's very important..
glLoadMatrixd( gl_para );
glFrustum (-100.0, 100.0, -100.0, 100.0, 1.5, 2000.0);