Shading a Surface Using Mesh
Mathematica supplies a useful way to apply shading to 3D plots when a mesh lies over the figure (here, an ellipsoid).
The resolution of the mesh is defined using the built-in Mathematica Mesh option. The option MeshShading then lets you define the pattern of the mesh shading. This can be made fairly complex, but in this Demonstration, only 2×2 matrices were used.