In article <3E9C4925.B3E7CACD@gmx.de>,
 Christoph Hormann <chr### [at] gmxde> wrote:

> I think it would be interesting to test.  One problem about blurred
> reflection is that low sample counts tend to generate noise that makes the
> result look very ugly.  Some 'slight' artefacts could be preferable in
> some situations.

If you look at the averaged texture method, the result of too few 
samples ends up as a blotchy, uneven blur instead of the severe 
grainyness of the old MegaPOV patch. I've been thinking about the 
possibilities of a patch that used precomputed sample directions 
smoothly perturbed by a pattern. This could avoid some of the extra 
computations of the averaged texture method and lower the number of 
samples required for a good result relative to the random sample method.

Another odd idea is adaptive sampling. For example, start off with a 
tetrahedron and subdivide each triangle into 4 triangles, sampling 
through the vertices and subdividing further when there's a significant 
difference between samples. Or have a minimum and maximum number of 
samples, split the minimum into two sets of samples and compare the 
results. If the results vary too much, take more samples and compare 
again. I did something like this in a development version of my 
proximity or curvature patterns (can't remembe exactly which, and didn't 
do much testing with it anyway).

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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