From: Angus Dorbie (dorbie++at++sgi.com)
Date: 05/24/2000 13:10:37
You can't project texture onto a transparent texture and expect it to
remain transparent.
The projected texture pass will draw the transparent object with the
projected texture on it and if the projected texture has alpha ==1 then
you will see the object as opaque. At the very best you are going to see
some sort of problems due to transparency. Performer tries to work
around some of these issues using stencil operations or depth equal
tests but there is no perfect solution without something like hardware
multitexture.
CHeers,Angus.
devrim wrote:
>
> Hi,
>
> I have been using performer projected textures within my application (
> based on the sample in the man page ) . We also have transparent
> textured billboards which are used for lens flare and static shadows. At
> some point project texture is enabled and then at some point again it is
> disabled. I have noticed that when I use projected textures transparent
> textures look as if alpha bits are set to 1. When I don't enable
> projected textures, it is just fine, we have nice transparency. It looks
> like the color bit count has also decreased.
>
> Any ideas ?
>
> /*===============================================
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> Simulation Software Development
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