Le 01/04/2011 10:18, Anthony D. Baye nous fit lire :
> I've managed to write a macro to generate a a sierpinski polygon of n sides, but
> I'm having a few problems.  First, I would expect the 4-sided polygon
> (sierpinski square) to look like a Mengher sponge, but it doesn't.
> 
> This is not my main problem, however.
> 
> What I'm trying to do is something like this:
> http://www.fractalsciencekit.com/gallery/orbital/f1058.jpg
> 
> which the site says is a sierpinski n-gon, but I can't figure out how they did
> it, and they aren't really saying except that it was done with their software.
> 
> If anyone can help me, I'd appreciate it.

My bad. The initial point is 0, not the vertex.
(in fact, the initial point is pretty irrevelant, as very soon its
initial coordinates get reduced to small influence (1/8 at third
iteration, and 1/1024 at tenth)

The colour is probably fancy (or based on hsv/hsl with addition made of
composing vectors)
Nevertheless, the lightness/whiteness seems a function of the likeness
to hit the position. Or the first iteration might start with a L=1, and
it get reduced for each iteration.

Instead of being attracted to one of the original vertex
( npos = (oldpos+vertex)/2 )
they might be using the original vertex (on a circle) with a reducing
radius as the displacement for each iteration.
Or using npos = oldpos + (vertex-oldpos)/factor
with factor not being exactly 2.

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