From: "Alexei A. Frounze" <dummy_addressee AT hotmail DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: please help with Texture coordinates!
Date: Sun, 25 Mar 2001 10:06:24 -0500
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To: djgpp AT delorie DOT com
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The best explanation is here:
http://www.lysator.liu.se/~mikaelk/doc/perspectivetexture/

I also have some code.... See on my page...

Good Luck
--
Alexei A. Frounze
alexfru [AT] chat [DOT] ru
http://alexfru.chat.ru
http://members.xoom.com/alexfru/
http://welcome.to/pmode/


"Kirill Pankratiev" <kirill AT free DOT fr> wrote in message
news:3ABDDBA9 DOT B937780E AT free DOT fr...
> Hello All!
>
> I would like to know how to use texture coordinates for
> perspective texture mapping.
>
> So far i 've always used the 'magic vectors' to transform
> points from screen space to texture space . ie
>
>      (u,v) =  T * invP * invV *(Sx, Sy, 1)
>   where invV is the inverse viewport transformation and invP
>   is the inverse Projection and T is the "Magic matrix"
>  Here we suppose that texture coordinates are
> (0,0) (1,0)
> (0,1) (1,1)
>
> What i want to do is to have U V associated with each vertex
> so that i can start at say (0,5,0.5) and end at (0.8, 0.8 ) of the
> texture
>  for exempla.
> When i use linear interpolation it works but it gives very poor quality
> because
> it doesn' t take into account perspective deformation.
> Can somebody please explain what i should do from the stage where i
> project
> the polygon?
>
> Thanks.
>
>