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# OpenGL Wierd OpenGL Results - why?

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I programmed a little FPS demo and crappy little terrain simulator to try out some lighting effects in opengl. They look as they should, given the GL commands I used on my PC with a Voodoo3 2000 AGP, but when I tried them on a friends PC with Riva TnT2 - the lighting didn''t work at all and the blended clouds looked really crap - you could see that the clouds were rectangular billboarded triangle strips. - Help! Why would the results differ - Could it be driver problems, I''m running Win2K with the only WHQL drivers available (oh - and the demo''s looked exactly the same as my PC on my friends - who has the same card, but Win98SE with the latest voodoo drivers for that OS) - so I''m assuming it''s not a voodoo problem. Can anyone help? Does the order with which you change GL lighting state commands matter? I am doing things in this order: 1)Set up material properties 2)Enabling lighting 3)Setting up GL_LIGHT0''s position and color 4)Enabling GL_LIGHT0 4)Drawing the scene Chris

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I don''t know for sure, but I have had two PCs and both of them have had not too good OpenGL support, which is a pity really. The thing about the clouds sounds like a color keying problem, and I don''t know enough about OpenGL to tell you about the lighting problem.

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#pragma twice

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The cloud problem could be simply caused by a different gamma or brightness setup on your friend's machine. I've experienced a similar thing with my programs on other people's machines. The problems could also be caused by drivers or your code, both of which seem unlikely. Try playing with the display settings on your friend's machine.

quote:
Original post by furby100

I don't know for sure, but I have had two PCs and both of them have had not too good OpenGL support, which is a pity really.

TNT2 supports openGL fine, as do all nVidia cards.

http://www.geocities.com/ben32768

Edited by - benjamin bunny on October 5, 2000 7:29:51 PM

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Thanks - friend tried on a GeForce 2 and it worked fine - must be Detonator 3 Drivers - I heard they had problems when used on older cards, rather than the Geforce cards.

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