On Monday, 29 November 2004 20:53, Curtis L. Olson wrote:
> I.e. if the polygons don't share exactly the same verticies they likely will
> round different directions in some situations and you are back to having
> z-buffer fights.  It's a nasty problem.  I've seen some applications
> that do a good job of handling it, but they have obviously put in a
> *ton* of time working out the issues (and are probably only running on a
> single specific kind of hardware/video card.)

Hmmm ... that's not good news.
The only way to make sure the polygons share the exact same vertices is to  
slice the lines into the underlying polygons which is a whole lot more work 
and increases the polygon count too.
Plus you end up with seam artifacts which need to be worked around.  :-\

> Do the textures stay compressed in video ram, does the texture render
> unit render from the compressed texture, or does it have to uncompress
> it in video ram before rendering it?

I'm not sure about that - I'll have to makes some inquiries and find out how  
video cards actually handle the rendering of compressed textures.
There would be no point if all the textures were uncompressed at the same time 
into VRAM.
The nice thing with compressed textures is that they are fairly simple to 
implement. The loading is the hardest part.


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