Polygon File Format
3 # number of polygonal chains
3 out # first polygonal chain, with 3 points, and is the out most chain
0 0 # point 1
0 10 # point 2
10 10 # point 3
3 2 1 # the order of the polychain vertices, must be ccw
4 in # Second polygonal chain, 43 points, and is a hole boundary
1 1 # All holes define after this must be contained inside the first boundary
2 1
2 2
1 2
1 2 3 4
4 out # Third polychain, another out most boundary
-5 -5 # this polychian can be in any where...
-3 0
-4 3
-6 0
1 2 3 4
