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richardve
01-06-2002, 11:17 AM
I've got a question for the NVIDIA or ATi guys or anyone else who knows it..

Who is actually breaking up quads to triangles?
The driver (cpu) or the hardware?

I'm very curious to this because there's a person @ www.gameskool.nl (http://www.gameskool.nl) (a Dutch gamedevelopment site) saying that quads aren't slower than triangles because they're broken up to triangles on the hardware with the triangle setup..

I always used to think that quads were broken up on the cpu.. was I wrong about that?

Tom Nuydens
01-06-2002, 12:09 PM
I believe the setup is indeed done by the hardware, as hinted by NVidia's OpenGL performance FAQ (http://developer.nvidia.com/view.asp?IO=ogl_performance_faq) .

However, I would still recommend against using quads. There are several cases where using quads might cause rendering errors that wouldn't have happened with triangles. The most important problem is that a quad isn't necessarily convex. Another more subtle problem was discussed in this thread (http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/002716.html) .

- Tom