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Undertaker
05-20-2005, 10:12 PM
I get horrible artifacts when i enable scissor test.
This only happens on my geforce2, on my radeon 9800 pro it works fine...

skynet
05-21-2005, 12:10 PM
I know this problem, too. It only happens on my old GF2 card. Seems to be a hardware issue?! It looks like scissoring forces the hw into some strange clipping mode which then produces sligtly wrong z-values...?

Another problem is something with cubemapping. You can actually see the "borders" of the normalizing cubemap on the bumpmapped surface. (Yes, I do use edge-clamping on the cubemap!) Again, only happens on GF2. GF3 and up donīt show any of these issues.

gator
05-21-2005, 09:16 PM
I had the same problems, sort of, but I managed to fix it by *always* disabling the scissor immediately after calling it, like:

glEnable(GL_SCISSOR_TEST);
glScissor( x, y, w, h );
glDisable(GL_SCISSOR_TEST);

Never, ever, leave it enabled.

sqrt[-1]
05-21-2005, 11:20 PM
I dunno about you guys but I have never had a problem with scissoring. (Mind you, I always leave it on and it is usually at the size of the render window) But I do occasionally change the size.

And this is with testing on Geforce 1-6.

Matt Zamborsky
05-21-2005, 11:36 PM
Do you set window style to SW_POPUP ? If yes, try SW_POPUPWINDOW.

It just an idea, nothing more.

Undertaker
05-23-2005, 01:42 AM
skynet I have the cubemap problem too :)
but only on gf2 again.

none of the suggested solutions work for me, thanx anyway for answering.

tryed the same program on gf3 an other cards and no such problem..maybe it`s a driver or hardware issue