Stellated octagon

The stellated octagon, or soc', is a polygon compound composed of two [[square]s. As such it has 8 edges and 8 vertices. If the components are equilateral triangles, the compound will be regular.

Vertex coordinates
Coordinates for the vertices of a stellated octagon of edge length 1 centered at the origin are given by:
 * (±1/2, ±1/2),
 * (±$\sqrt{2}$/2, 0),
 * (0, ±$\sqrt{2}$/2).