Nicolas Alvarez wrote:

> AFAIK, this algorithm doesn't shoot rays per pixel, really. Just lots of
> rays, and starting from the light.
> 
> Note it's not the common "backwards raytracing" like POV-Ray has. This
> is forwards.

I think it actually does shoot rays from camera. The ray shooting
recursive function returns when an emitting surface (or certain depth)
is found. It actually doesn't matter (from physics point of view) where
you start: from camera of from the light as the ray paths are identical.

I think normal raytracers start from camera and go straight from first
intersection to light point. That is the difference here. In brute force
you keep on going (shooting random rays from diffuse surfaces) and you
hope you hit a light at some point. And that is why all light sources
must basically have surface to be able to hit.

Yes, I oversimplified and I'm still a n00b so please correct all the
mistakes.

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