nemesis <nam### [at] nospamgmailcom> wrote:
> So, I wonder if you guys ever came in touch with the Lightcuts Global
> Illumination algorithm?
>
> http://www.cs.cornell.edu/~kb/projects/lightcuts/

Looks very, very, *very* promising when it comes to handling large amounts of
point or area lights.

I'm not sure whether it can be integrated into PoV-ray to do something
radiosity-like though.

Could be possible to do this in a multi-iteration approach though:

- Set up all classic light sources (point, area, spot etc. lights)

- Compile virtual light sources from all objects having an emissive term
(objects with ambient finish and - guess what! - media; hey, this may become
really good after all!); as it seems, number of light sources generated is
*not* an issue, so we can go into extremes here

That's our initial setting; to get radiosity-like effects, we can go ahead like
this:

- Compile more virtual light sources from all objects having a *diffuse* term
(objects with a diffuse surface, and simple scattering media), by sampling all
the incoming light from the initial set-up (using lightcuts of course!) and
multiplying with the object's diffuse color.

- Repeatedly re-compile all the virtual "diffuse-term light sources", now taking
into account the light coming from other diffuse sources, until we're either
confident that they are "stable", or until we hit some configurable hard
recursion limit.


Caustics could be done by running a classic photon pass first (or multiple times
in between), and creating a light source for every photon that hits a diffuse
surface. I guess it may even be possible to modify the photon pass in a similar
fashion.


Just a bunch of thoughts though. Maybe I'm missing some serious obstacles.

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