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Cartman
08-02-2002, 01:15 AM
Hi,

I've readed recently in some post that it's possible to use cube maps to perform per-pixel attenuation. How is that possible?
Can someone explain me that ?

tks
Cartman

JasonM [ATI]
08-04-2002, 01:51 PM
Are you sure you don't mean 3D textures? If so, have a look at the RADEONDotProduct3 (http://www.ati.com/developer/sdk/RadeonSDK/Html/Samples/OpenGL/RadeonDotProduct3.html) sample.

-Jason

SirKnight
08-04-2002, 05:46 PM
I have never seen a cubemap used for attenuation, nor can I see how that can be done. As Jason said 3D textures can be used for attenuation as long as your hardware supports them. If not it will be slow as hell. http://www.opengl.org/discussion_boards/ubb/smile.gif Even then I wouldn't use 3d textures for that. I don't like the current performance of 3d textures and doing attenuation with 2D textures works just as good and faster. I guess if you needed some kind of funky looking attenuation effect they will be good but for a pointlight where the light radiates equally in all directions, it's better to use some other method.

-SirKnight

okapota
08-05-2002, 12:55 AM
maybe you mean using a cube map to filter the attenuation to create spot like effects, ot other funky looking attenuation effects. http://www.opengl.org/discussion_boards/ubb/smile.gif