"Jim McElhiney" <mun### [at] excitecom> wrote...
> Christoph Hormann wrote:
> > That complies well with the observations that have been made with the
> > sample set, namely that it is fairly good at certain count values but
> > quite limited for values in between.  When you use 'normal on' in
> > radiosity (i think this was added by Nathan) it is not guaranteed that
the
> > first N samples are actually used when you use 'count N'.
>
> It is certainly designed to work well for any number over 50, but it
> is designed around the idea that it should always use indices 1..N.
> Using anything else would certainly give problems with the current
> rad_data.  It would be better to rotate the whole set of points, then
> take 1..N, rather than taking a "slanted" sample from the set.

The code does rotate the points, so to speak, to match the normal.  The code
already was capable of doing that, I just changed it to use the perturbed
normal instead of the raw normal (when the user enables the feature).

The problem is similar to problems with combining reflection with a
perturbed normal.  Because the normal is inconsistent with the geometry,
this method shoots some of the sample rays _below_ the surface of the
object, which is not at all what we want.  I choose to simply throw out
those samples and re-shoot them if such a case was detected.

-Nathan

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