Hi folks.

I am currently in the process of rendering my first animation using
radiosity. Actually it's not working too well, but the experts will probably
tell me I'm rendering the wrong sort of scene. Anyway, will hopefully post
the results if they can be compressed to a reasonable size without too much
loss... (Since most of the image is black, this seems possible.)

But anyway, my question...

Does POV-Ray do *real* radiosity?

According to my understanding (which may or may not be correct) "radiosity"
algorithms start from the light source(s) and follow the paths of the rays
forwards into the scene, eventually reaching the camera. However, POV-Ray is
"radiosity mode" seems to still follow light backwards, only this time
attempting to take diffuse interreflections into account. (Actually I am
*extremely* fuzzy on exactly what POV-Ray does do... the documentation seems
awefully vague.) Does this really count as radiosity?

I'm interested in the difference between POV-Ray's radiosity mode and photon
mapping... IIRC, the latter is designed only to forward-trace specular
reflections and refraction. Photon maps appear to be totally independant of
the camera angle, whereas the animation I'm currently rendering seems to
indicate that radiosity IS camera dependent (or just uses a lot of random
sampling), further implying that it traces backwards not forwards. Could the
photon mapping algorithm be changed to include diffuse elements also? Would
this be worth doing?

Radiosity is still supposed to be an "experimental feature"... is it likely
to change in the next version of POV-Ray?... is there likely to BE a next
version of POV-Ray?

Thoughts? Opinions? (No doubt flames too...)

Thanks.
Andrew.

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