6 
convex
6
1 0.375 -0.375 0.5 -0.375
2 0.5 -0.375 0.625 -0.5
3 0.625 -0.5 0.625 -0.625 
4 0.625 -0.625 0.5 -0.625
5 0.5 -0.625 0.375 -0.5
6 0.375 -0.5 0.375 -0.375
