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opcode
11-01-2004, 01:59 PM
Recently I've been rendering my scenes front to back to take advantage of Z-culling.

Per my gluPerspective call, the values of my near/far clipping planes are 1/200.

Now, does that mean that everything outside the clipping planes will not be sent the pipeline? Or do I have to exclude those vertices myself. What about the rest of the object? Say your on the other side of a building, should you really have to render the side just because it is in the clipping plane?

One more thing, I've been trying out a multipass solution I found in a china joy 2004 presentation. Is a multipass solution something you would normally use, or is it for special cases where your in desperate need of optimization.

Thanks

mikael_aronsson
11-02-2004, 06:15 AM
Hi !

Nope, the clipping is done by OpenGL, so it has to get the triangles before it can clip them, so everything is sent down the pipeline no mater what your clipping planes and view frustum is, there does exist OpenGL extensions though to do frustum clipping.

Mikael