I understand what you mean. The top-left, top-right, and bottom-right are ok, but what about bottom-left? The other three are on a convex extreme of the planet, but the third is in the middle of a concave. How would you calculate the position of this point? would it be just diagoally from the top right?
Unfortunately while this may work in 2D, I don\'t know if it would work in 3D with 6 sides instead of 4.