vertices = D1:160 D2:160
u = from 0 to (4*PI) D1
v = from 0 to (2*PI) D2

a = sin(u)
b = cos(u)

c = sin(v)
d = cos(v)

e = sin(u/2)
f = cos(u/2)

x = b*(f*(sqrt(2) + d) + e*c*d)
z = a*(f*(sqrt(2) + d) + e*c*d)
y = -e*(sqrt(2) + d) + f*c*d