def _make_tris_fan(n_vert):
 tris = np.zeros(((n_vert - 2), 3), int)
 tris[:, 2] = np.arange(2, n_vert)
 tris[:, 1] = (tris[:, 2] - 1)
 return tris

def _make_tris_fan ( n_vert ) : tris = np . zeros ( ( ( n_vert - 2 ) , 3 ) , int ) tris [ : , 2 ] = np . arange ( 2 , n_vert ) tris [ : , 1 ] = ( tris [ : , 2 ] - 1 ) return tris
make tris given a number of vertices of a circle-like obj .