In article <409495bc@news.povray.org>,
 "Ilia Guzei" <igu### [at] fozziechemwiscedu> wrote:

> Mersenne twister can probably produce a random enough (as in "uniform")
> distribution but I'd rather do it exactly if possible.  I need to do it once
> to generate an input table for an application, so time and algorithm
> efficiency is irrelevant.

It is not possible to do so for large numbers of points. As I recall, 
the largest number of points that can be perfectly evenly distributed is 
20, the triangles of an icosahedron or vertices of a dodecahedron.

If you need points with overall even spacing, and the spacing given by 
polyhedron subdivision is too uneven, the electrostatic repulsion method 
mentioned can help you minimize the unevenness. You basically model each 
point as a particle that repels the other particles by the 1/r^2 law. 
Figure out which direction the surrounding particles are pushing each 
particle, move it slightly in that direction and project it's new 
position onto the sphere, and repeat until the particles settle down 
enough.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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