Warp wrote:
>   Unless I understood incorrectly, the "lightcuts" algorithm is not about
> global illumination, but about speeding up illumination from hundreds of
> thousands of point light sources, which is a rather different thing. (Global
> illumination is about light reflecting from surfaces and illuminating other
> surfaces, in turn reflecting from them and illuminating yet other surfaces,
> and so on. "Lightcuts" looked like an algorithm for direct illumination only.)

Yes, I was in doubt too.  But in the webpage for the paper they say: 
"It handles arbitrary geometry, non-diffuse materials, and illumination 
from a wide variety of sources including point lights, area lights,... 
and indirect illumination."  They couldn't just be plain lying.

So, I did a test using the Blender implementation:
http://img440.imageshack.us/img440/1255/lightcutstestzg0.jpg

Only lightsource is an area light outside and above the window.  So, 
indeed it handles indirect illumination automatically...

It has a lightcuts panels with quite a few parameters, among them, 
number of point lights generated from an area light.  The default is 
immense, so I fearfully put it down to a modest 128 as well as a 
indirect light factor about the same.  I think such "low" settings can 
be accounted for the splotches and "cuts" seen.

OTOH, it took 44 minutes on a P4 2.66.  Not as fast as I had hoped for... :P

Next, I'll try to export to pov and play around with radiosity.  I 
didn't like the radiosity in Blender, even with quite lots of 
subdivision, it still looks quite ugly and not on par with the lightcuts 
picture...

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