"Christoph Hormann" <chr### [at] gmxde> wrote...
>
> Methods based on repulsion/minimizing potential energy should work equally
> well with both high and low number of samples.  But for using the same set
> for both low and high number of samples is important to have a good way of
> sorting them.  It has been mentioned before that the set of samples right
> now in POV-Ray is only quite uniform at certain numbers of samples.

True.  It seems POV's sample list has been optimized for specific numbers of
samples.  Does anybody know which sample counts produce the most evenly
distributed samples?

Also, this brings up a good point that if we can find a fast way to generate
a new set of samples for each render, we could theoretically come up with
better distributions for all sample counts.  The key here is to be able to
generate a good sample list quickly.  Another benefit to creating a custom
sample list for each render is that we could create sample lists for things
other than the standard lambertian cos-theta distribution.  This would
potentially allow us to produce more realistic results for a wider range of
surface materials.

Also note that such sample-generating code could be useful for photon
mapping.  The current photon mapping implementation creates a fake
distribution by shooting photons in a spiral and jittering the results.
While this generally produces good results, it can also lead to artefacts if
the jitter value is too small, and can also lead to uneven samples if the
jitter value is too large.

-Nathan

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