/**
* checks whether an edge is shared by two faces f1 and f2: the function check whether the
* corresponding vertices appear both in f1 and f2, in the correct order. LCA: a' tester
*/
public boolean areEqual(
TriangulationDSFace_2<X> face1, int i1, TriangulationDSFace_2<X> face2, int i2) {
HalfedgeHandle<X> edge1 = new HalfedgeHandle<X>(face1, i1);
HalfedgeHandle<X> edge2 = new HalfedgeHandle<X>(face2, i2);
TriangulationDSVertex_2<X> v1 = edge1.getVertex(0); // first vertex of edge1
TriangulationDSVertex_2<X> v2 = edge1.getVertex(1); // second vertex of edge1
boolean contained = edge2.hasVertex(v1);
if (contained == false) return false;
contained = edge2.hasVertex(v2);
if (contained == false) return false;
if (v1.equals(edge2.getVertex(0))) return false;
return true;
}
