[general]
name = Boy2;
comments = Boy surface. Werner Boy (1879-1914).;
a1_min = 0;
a1_max = 180;
a1_steps = 80;
a2_min = 0.1; 
a2_max = 179.9;
a2_steps = 80;

[formula]
a = cos(A1) * sin(A2);
b = sin(A1) * sin(A2);
c = cos(A2);
aa = sqr(a);
bb = sqr(b);
cc = sqr(c);

X = 0.5 * ((2*aa - bb - cc) * (aa + bb + cc) + 2*b*c * (bb - cc) + c*a * (aa - cc) + a*b * (bb - aa));
Y = 0.5 * 1.73205080757 * ((bb - cc) * (aa + bb + cc) + c*a * (cc - aa) + a*b * (bb - aa));
Z = -0.125 * (a + b + c) * (pow(a + b + c, 3) + 4 * (b - a) * (c - b) * (a - c));