[Mesa3d-dev] Re: [Dri-devel] Fog on tdfx (was: GL_EXT_fog_coord, etc.)

[Gareth H. <ga...@va...>]

Brian Paul wrote:
> 
> I'm thinking that if we're using orthographic projection that we
> could use GR_FOG_WITH_TABLE_ON_FOGCOORD_EXT (available on Voodoo3
> and later, don't know about Banshee or Voodoo1/2) if we added a
> fog coord to the Glide vertices and computed it from the vertex Z
> somewhere in the vertex setup code.
> 
> I think this would be much more easily done in the new tdfx-3-0-0
> driver than the current driver.
> 
> Gareth, could we put GR_FOG_COORD into the vertex struct where
> we currently have a GLuint padding?  I haven't examined the vertex
> layouts very much yet.

Yes.  It's on my tdfx-3-0-0 todo list (which, unfortunately, is still
rather long).

I can look into this sooner rather than later if you like.  I'm
travelling again today, but was going to investigate the 32bpp
performance hit tonight.  It should be fairly easy to hook up the fog
coordinate stuff, especially since we've got a place for it in the
default vertex structure already.

-- Gareth