The NCSA Imagemap Format

  Keyword  URL          Coordinates

  rect       your_url_here  x,y x,y     
				
  circ       your_url_here  x,y x,y

  poly       your_url_here  x,y … x,y


Rectangles are specified by their left, top, right and bottom coordinates.

Circles are specified by their left, top, right and bottom coordinates.

Polygons are specified by a list of vertices.