Chris Huff wrote:
> 
> In article <39665ac3@news.povray.org>, Warp <war### [at] tagpovrayorg>
> wrote:
> 
> >   Yes. Moving vertices around is not problem at all. Someone has only to
> > code it.
> 
> I have attempted to add displacement mapping to meshes, but I only got
> "scrambled triangles". I think the problem is in my understanding of the
> mesh code...
> 

I add my opinion to this matter, of which I know nothing:-)
For obtaining good displacement result, you have to subdivide your mesh
(patch, whatever) into micropolygons (to such size, that they cover one
pixel) and then apply displacement. This is how it is done in RenderMan.
Only problem here is the fact that in this case the size of geometry
will increase tenfolds. Of course, there are papers available for
caching this geometry (tesselating part of surface only when ray hits
it), so it could be managed even in case, when whole tesselated geometry
does not fit into memory. (But in this case it would be better to change
rendering order: now it is performed line-by-line, with caching it would
be better to render bucket-by-bucket (where bucket is small picture
area, e.g. with size 16x16) in order to take advantage of spatial
coherence. Or could this be done already by specifying some parameter?).
I don't know, to what size patch is tesselated in POV-Ray, if into
microtriangles (with covered size one pixel), then it should be fairly
easy. But I guess, that it is tesselated until it is flat enough,
resulting in much bigger triangles.

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