Mark Weyer wrote:
> 
> > Well, it is not easy to create such a continuously uniform distribution,
> > uniform at a certain number is fairly simple on the other hand.
> 
> What is the problem you are adressing here?
> 
> [...]

Quoting from the source:

A bit of theory: The goal is to create a set of "random" direction rays
so that the probability of close-to-normal versus close-to-tangent rolls
off in a cos-theta curve, where theta is the deviation from normal.
That is, lots of rays close to normal, and very few close to tangent.
You also want to have all of the rays be evenly spread, no matter how
many you want to use.  The lookup array has an array of points carefully
chosen to meet all of these criteria.

The problem is similar to the classical "How can I arrange N points evenly
on a sphere" problem like described in:

http://www.ogre.nu/sphere.htm

Just that it is hemispherical, not really uniform and it not only has to
be good for N points but also for N-X points (X = 1..N-1)

Christoph

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