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View Full Version : Degenerate Tri-Strips vs Tri-Lists Again



V
03-27-2001, 08:30 AM
After reading Nvidia's presentations from the GameDeveloperConference, i have picked up conflicting information. In Richard Huddy's presentation he recommends using Degenerate Tri-Strips (via indexing) while the OpenGL optimizations indicate to *never* use Degenerate Tri-Strips. Perhaps that indication is for non-indexed strips?

It seems that if your mesh data is already arranged as a batch of Tri-Strips, then connecting those batches via a degenerate tri format reduces index-bandwidth and gives the driver less to fetch per-triangle into the cache-

Any clarifications or recommendations would be helpful- ATI? Matrox?

jwatte
03-27-2001, 09:12 AM
How about writing a test case and timing it? I'd be very interested in seeing what results you'd come up with.

I also believe the main penalty is in the set-up overhead per call to DrawElements(), rather than the extra two vertexes to start a new strip, at least for hardware transform and lighting.