Re: Tips for debugging D3D Textures & DirectSound?

On Fri, 22 Oct 2004, Ove Kaaven wrote:

> fre, 22.10.2004 kl. 06.26 skrev Nadav Frum:
> > However, to my understanding, the vector (x, y, z, 1.0) would also be
> > correct.
> 
> Only if you don't care about proper perspective. This transformation
> loses the W information, which the renderer needs to implement
> perspective-correct texture mapping, among other things. If you fix W to
> 1, you'll get an affine texture mapping, which is likely to look quite a
> bit uglier. (If you want, you can look at chapter 3.5.1 in the OpenGL
> 1.5 specification to see exactly how W is used when associating texture
> coordinates with fragments, in mathematical terms.)

I decided that I do care about proper perspective.  I have read the OpenGL 
spec and the w coordinate is used when interpolating the fragments data in 
relation to its surrounding vertices.  My RHW patch is null and void.

Nadav Frum
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