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Ninja
03-25-2003, 02:45 PM
Hi!

I just bought a radeon 9700 and tried some cg examples from the cg-toolkit. Unfortunately, there were some ugly banding artefacts in some of them. How is that possible? I thought the precision problem was fixed on radeon 9700?

Regards, Ninja

Ninja
03-25-2003, 03:48 PM
Here is a picture of a diffuse bumpmap example (no specular!?)
http://www.mdstud.chalmers.se/~md8smaug/bump.jpg


//Ninja

jwatte
03-25-2003, 04:49 PM
I can see two possible alternatives:

1) maybe you're not using the right fragment program profile?

2) maybe the artifacts come from the normalization cube map?

Especially if your control panel is set to convert textures to 16 bit, it's gonna really suck for 2).

Usually, it's actually faster to normalize using dp3, rsq and mul than to do a cube map look-up, btw.

Ninja
03-25-2003, 05:04 PM
Ok, thanks!
I changed the texture performance to high quality and now it works fine, so I guess it was problem nr 2.


//Regards, Ninja

sqrt[-1]
03-25-2003, 05:08 PM
I'd bet it is the cube map as well, as I had a similar problem recently.

See thread: http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008860.html