#http://www.mathcurve.com/courbes3d/couronnetangentoidale/couronnetangentoidale.shtml

vertices = 12000

t = from 0 to (20*PI)

a = 10
b = rand2(1, 10)
n = rand2(0.5, 10)
 
x = a*cos(t)
y = a*sin(t)
z = b*cos(n*t)
