A Schlegel diagram is a planar representation of a polyhedron. First, the polyhedron is projected from its center onto the unit sphere. A face is chosen and the spherical polyhedron is projected to the nearest tangent plane parallel to .

This Demonstration shows mazes on a polyhedron given by a Schlegel diagram. The path should go from the black dot to the gray dot through some or all of the faces without crossing a red edge. The top face corresponds to the exterior of the bounded region.

Sometimes the diagram can be improved by using "adapt diagram."