The general equation is simple, should have seen it ages ago. This must be how blender generate their meshes. Use the equation, and plugin numbers for x,y, and z at certain increments, based on the required resolution. Probably also accounts for lack of details near the top centre of meshes like this:
Where the increments in z moves the cross-section outside defined space, where x and y become imaginary.
Another wonderful thing also happened, but I'll keep that private :-) Time to sleep me thinks. *yawn*
Cheer,
Steve