Mark Weyer wrote:
> That's what I thought, except I expected the probability to be
> sin(theta)
> (or cos(theta), if theta is the angle between ray and TANGENT), implying
> fewer rays close to normal than close to tangent. Is this a typo?

What you must remember is that you are trying to estimate the lighting 
at a particular point.

If you have a light source almost tangential to the surface it doesn't 
illuminate much and one almost normal to the surface gives high 
illumination. So, if all the samples are weighted the same you want most 
samples from the normal direction and few from tangential to give the 
best estimate.

> 
> Why is the lookup array fixed? It might be calculated at program start,
> allowing for varying length.

I suppose it could be, and I've thought about doing this. However you 
would have to calculate an array for each level of radiosity recursion 
because the code reduces the number of samples taken at each subsequent 
recursion level. And the results wouldn't be very different anyway.

> 
>   Mark

Mike Andrews.

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