From: Bill Gosper <gosper@alum.mit.edu>
Due to a 2D pattern-generator discovered by two exceptional brothers I'm tutoring: http://gosper.org/p5d1.png .
Notice the pentagrams are a little bit skewed. A program I wrote also generates skewed pentagonal patterns in a square grid when run with certain settings: http://www.tiac.net/~sw/2005/03/Mandala/minsky10.html
From: Fred lunnon <fred.lunnon@gmail.com>
This might make an interesting wall design for a public space ...
As long as certain members of the public don't know you did it.
Any comments on how it's done? WFL
Mine is, find cycles in a function that rotates a grid by 36 degrees, but using a cheat method by Minsky: http://www.inwap.com/pdp10/hbaker/hakmem/hacks.html#item149 and illuminated by, er, Gosper: http://www.inwap.com/pdp10/hbaker/hakmem/hacks.html#item151 It's something like epsilon = sqrt( 2 * ( 1 - cos( pi / 10 ) ) ); x = x - round( epsilon * y ); // old y y = y + round( epsilon * x ); // new x This page explains my program in more detail & has an applet to play with: http://www.tiac.net/~sw/2005/03/Mandala/ --Steve