GL_HP_occlusion_test

OpenGL OpenGL: Advanced Coding
1

I’ve just installed the 27.10 drivers on a GeForce 256 DDR. I wanted specifically to look at this extension. Is it not supported on older geForce cards?

Incidentally, has anyone else had problems installing these drivers? I know they’re not official, so it’s no big deal - but when I rebooted after the update the screen was ‘stuck’ on the W2K white loading screen, although the system worked fine! I could still run apps like Windows Explorer, and close the system down. It was almost as if the front and back buffers wouldn’t swap!

2

I think that new extension is for the geforce 3 only. I tried to use it on my geforce 256 w/ the 27.10 drivers and it wouldnt work. I also had problems w/ the drivers (but different than yours) but thats why they are beta and for testing only.

-SirKnight

3

BTW what are the enumerants for the extension? The spec says “unfinished” anybody knows them?

Regards,
-Lev

4

GL_OCCLUSION_TEST_HP = 0x8165;
GL_OCCLUSION_TEST_RESULT_HP = 0x8166;

Now that you mention it, they aren’t in the spec – makes me wonder where I got them.

– Tom

[This message has been edited by Tom Nuydens (edited 01-29-2002).]

5

Originally posted by Tom Nuydens:
[b]GL_OCCLUSION_TEST_HP = 0x8165;
GL_OCCLUSION_TEST_RESULT_HP = 0x8166;

[/b]

These values are correct, and are the same values our Oxygen and Wildcat drivers use.

Barthold
3Dlabs

6

Is GL_HP_occlusion_test fast enought on GeForce3 ? Is it worth using it ?
I tried the Delphi Demo for occlusion, and
100-110 fps for a teapot and a ball doesn’t look really fast…

7

It’s very fast on GeForce3. There are so many uses for this extension that it’s definitely worth it.

8

Originally posted by opla:
Is GL_HP_occlusion_test fast enought on GeForce3 ? Is it worth using it ?
I tried the Delphi Demo for occlusion, and
100-110 fps for a teapot and a ball doesn’t look really fast…

… but what you overlooked is that the ball has 16000 triangles

I get about 110 fps when the ball is visible, and 155 when it’s not. The occlusion test itself is by no means free, but I found that if you don’t do it on objects with very small triangle counts (less than a few hundred), it’s always a win.

– Tom