#  nodes.txt
#
#     5  7  6
#           
#  4  8  2
#         
#  9  1  3
#
  1.0  0.0
  2.0  1.0
  2.0  0.0
  0.0  1.0
  1.0  2.0
  3.0  2.0
  2.0  2.0
  1.0  1.0
  0.0  0.0