note about exterior edges
note about exterior edges

JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,JianpingCAI/libigl,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,aaronzou/Shape-Deformation,aaronzou/Shape-Deformation