Question

How to turn a point3d array from Cartesian coordinates into Spherical coordinate system (assuming its geometric center is 0,0,0 in spherical system)?

Answer 1

Copying the formula from Wikipedia, apply this to each entry in the array:

r = Math.Sqrt(p.X*p.X + p.Y*p.Y + p.Z*p.Z);
if (r == 0) {
  theta = 0;
  phi = 0;
} else {
  theta = Math.Acos(p.Z/r);
  phi = Math.Atan2(p.Y, p.X);
}