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BwB
03-15-2001, 10:15 PM
Well, I've just been reading through nVidia's performance FAQ available in the OpenGL SDK. One thing I've noticed is that none of the "optimized" vertex formats include both a color component and a normal. Does this mean that for performance reasons we shouldnt both color and light our polys? Or should we just use immediate mode if we want both color and lighting? I planned on doing my own lighting anyways so I can live without the hardware lighting but... just seems odd to me.
Please forgive me if this has been discussed before http://www.opengl.org/discussion_boards/ubb/smile.gif

mcraighead
03-15-2001, 10:30 PM
Unless you're using color material, it doesn't make sense to mix color and normal.

Remember that the list of formats is totally obsolete with 10.xx drivers.

- Matt

BwB
03-15-2001, 11:40 PM
My worlds have both precalculated static lighting (color) and dynamic lighting (which, I hoped I could do in hardware but it doesnt look that way). Whats up with the 10.xx drivers? Are all formats optimized the same? I have refrained from using the 10.xx drivers simply because they are the newest (hence most untested) but I'm downloading 10.80 now (install tomarrow http://www.opengl.org/discussion_boards/ubb/smile.gif).
Any comments on my static/dynamic lighting? I'd like to know if I have a good idea going with that or if there is a much better way.
Thanks!!

Tom Nuydens
03-16-2001, 12:25 AM
Originally posted by mcraighead:
Unless you're using color material, it doesn't make sense to mix color and normal.

This doesn't apply to BwB's question, but... One reason to mix colors and normals might be because you want to use environment mapping but not lighting?

- Tom

zed
03-16-2001, 03:14 AM
even with the 10.80 drivers the q3 format seems to be ralatively the quickest. all formats aint equal or are they?

Nutty
03-16-2001, 05:04 AM
You can use color and dynamic lights if you use a vertex program. Simply multiply the incoming color by the lighting value, to affect it's brightness..

works fine for me..

Lars
03-16-2001, 05:14 AM
Yes but doing this results in unaccelerated TnL at least for people who do not own a GeForce3.

There are other things not very clear in the performance FAQ, for example they never mention the secondary color.

Lars