> > I'm trying to code the cornell box but using Photons Mapping instead of
> > radiosity. So far, no success. I've got all my photons{} blocs in my
> > global, light and objects. The scene is very simple but all I get is
> > essentially the same render as with ray-trace only.
>
> This last sentence shows a misunderstanding of how POV works. POV is a
> raytracer, there is no "ray-trace only" mode, it is always raytracing.
> The radiosity algorithm is not a patch subdivision method, it uses
> raytracing to collect samples.

What I meant is that I get the same render result as when I remove every
"photons {}" blocks from my global, light and objects descriptions thus
leaving only the regular ray-trace render in action.

While I don't know the implementation details of radiosity in POV-Ray,
radiosity and photon mapping is not quite the same technique. I'm interested
in using the photons mapping technique here. I understand that photons
mapping proceeds in two passes. First pass, shoots and collect photons
either on surfaces on in a kd-tree or on both at the same time using the
raytrace engine. Second pass, renders as usual using raytrace but add the
radiance values computed from stored photons using a sort of area-averaging
procedure.

If I remove the photons {} blocs from a scene, the first pass of photon
shooting will not happen and thus the render pass will not have any radiance
data to add thus render like a normal raytracer.

I hope this removes any confusions as to what I meant.

WhiteZebra

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