View Full Version : Conical Frustum

04-28-2003, 10:28 AM
I'm new to OpenGL and need to modify some existing code. I'd like to change the existing perspective projection so that it looks like the viewer is looking through a cone, rather that a pyramid.

Can this be done by specifying the frustum to be non-rectangular? Or, do I have to clip things to a circle? If I have to clip myself, is this fairly easy to do?


04-28-2003, 11:15 AM
Probably easiest to have a textured quad at the near clipping plane. The texture could have a black area with alpha = 1.0 and the middle would have alpha = 0.0 for the circle. Then use blending.