#http://www.mathcurve.com/surfaces/elasticite/elasticite.shtml
vertices = D1:200 D2:400
u = from 0 to (PI) D1
v = from 0 to (PI*2) D2

a = rand2(1, 10)
b = rand2(1, 10)
c = rand2(1, 10)

m = sin(u)
n = cos(u)
i = sin(v)
j = cos(v)

t = i*i + c*c*j*j*(n*n/a/a + m*m/b*b)

x = c*c/a*n*j/t
z = c*c/b*m*j/t
y = c*i/t
