This morning's prompt was 'peacock feather'.

I've been messing around with marching triangles and tetrahedra, because I can see how to making contour mapping procedural. Squares are also quads and subdivide into a pair of triangles. This corner triangle can be projected down to the center of a world polyhedron as a skinny tetra out out some distance for a triangular prism which 'easily' subdivides into three triangles.

Any tetra can be thought to have vertices inside or outside of a shape or the earth if delving...

All points can be inside or all can be outside, which is a little boring. If three are inside and one outside, or one inside and the other three outside, then we can draw a triangle at the three surface points. If half, there are four surface points making a pair of triangles as the surface, where inside becomes outside or vice versa.