I generealized the tools from the Polygon Portal sketch
([url]http://www.geogebratube.org/material/show/id/131862[/url])
to give the user more control, working for your choice of vertices, center and turning point.
Though this only has tools for triangles and quadrilaterals and the original did regular n-gons.
Hope it's fun for you and you can make something pretty!
