The Hausdorff Core of a Simple Polygon
These are applets which illustrate some of the interesting cases of the Hausdorff Core problem.
The definition of Hausdorff distance: here
A simple example: here
A challenging example: here
A simple but difficult case: here
For further information, please see my Hausdorff Core papers. The first presents an FPTAS for the general
problem on simple polygons, while the second follows up with An exact solution for simple polygons with a
single reflex vertex:

Reza Dorrigiv,
Stephane Durocher,
Arash Farzan,
Robert Fraser,
Alejandro LópezOrtiz,
J. Ian Munro,
Alejandro Salinger and
Matthew Skala.
Finding a Hausdorff Core
of a Polygon: On Convex Polygon Containment with Bounded Hausdorff Distance.
Proceedings of the Algorithms and Data Structures Symposium (WADS), LNCS 5664, pp. 218229, 2009.
[Preprint PDF]
[via Springer]
 Robert Fraser and
Patrick K. Nicholson.
Hausdorff Core of a One Reflex Vertex Polygon.
Proceedings of the 22nd Canadian Conference on Computational Geometry (CCCG), pp. 183186, 2010.
[PDF]
[via CCCG]
