polyop.flipNormals <Poly poly> <facelist>Flips the normal of the specified faces.
polyop.retriangulate <Poly poly> <facelist>Retriangulates the specified faces.
polyop.setDiagonal <Poly poly> <int face> <int face_vert1> <int face_vert2>Sets a diagonal of the face between the two vertices.
The face must have a degree greater than three and the two vertices must not be connected by an edge.