Full-Guard Diagrams

A set of "regression test" diagrams to demonstrate correct rolling around/inside an arbitrary polygon, allowing every segment and vertex to be a potential obstruction to the rolling.

For the quads, the polygon is shown in white. The upper left is a pair of spirograph curves -- one inside and one from rolling outside the polygon. The upper right is a "roll diagram" showing the wheel and pen at various points along the curve. The lower left shows several curves generated with the number of complete rotations for a circuit varying between 4 and 9, and the lower right shows a set of curves where the initial offset for the pen position various between 0 and pi.