v 10000 10000
v 12000 30000
v 10000 50000
v 30000 48000
v 50000 50000
v 48000 30000
v 50000 10000
v 30000 12000
x
v 25000 25000
v 35000 35000
v 25000 35000
#

Same as 'polygon_concave.txt', but with a triangular hole in it.
