I think you'd find a lot more noise in the image (and it would probably be
a lot slower).  What I was thinking was this:

Right now, when POV takes samples, it averages them and saves just the
color.  It could, however, save the direction/brightness of each sample.
Then, instead of just doing a weighted-average of nearby points to
interpolate in-between colors, you would reuse the individual samples.
With knowledge of both direction and brightness, you could calculate
diffuse, phong, and specular components.  This might be considerable slower
(100+ samples per intersection), but probably not a great deal slower, since
you would be reusing samples instead of tracing them.  Going through a 'for'
loop 100 times doing a few dot products each time is not _that_ time
consuming.

I would keep an option of the current version, though, for speed reasons.
I also think it is important to generalize radiosity a little bit more, so
that it works for reflections (like the furry cat picture in the latest
IRTC) and allows more recursion depth.

Right now I'm working on the photon map stuff, but this is interesting
enough for me to play with it too.  :-)

-Nathan


Margus Ramst wrote:
> 
> Well, knowing only the general principles of POV's radiosity system, I'm not
> sure whether this is a good idea but...
> Maybe shoot out a small number of sample rays (count/10 or something) at
> every pixel and add this to the value calculated by the conventional method.
> Perhaps make this an object-level option.
> Since features usually represented by bump maps would (in real life) not
> have great effect on the shape of the object, the weight of the colors
> calculated by this pixel-by-pixel method could be small, so the the
> statistical errors resulting from using few sample rays would (in theory) be
> negligible.
> I can make really long sentences, n'est pas?
> 
> Margus.

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