CGAL 5.2.1 - Surface Mesh
Surface_mesh/check_orientation.cpp
#include <CGAL/Simple_cartesian.h>
#include <CGAL/Surface_mesh.h>
typedef Mesh::Vertex_index vertex_descriptor;
typedef Mesh::Face_index face_descriptor;
int main()
{
Mesh m;
// Add the points as vertices
vertex_descriptor u = m.add_vertex(K::Point_3(0,1,0));
vertex_descriptor v = m.add_vertex(K::Point_3(0,0,0));
vertex_descriptor w = m.add_vertex(K::Point_3(1,1,0));
vertex_descriptor x = m.add_vertex(K::Point_3(1,0,0));
m.add_face(u,v,w);
face_descriptor f = m.add_face(u,v,x);
if(f == Mesh::null_face())
{
std::cerr<<"The face could not be added because of an orientation error."<<std::endl;
f = m.add_face(u,x,v);
assert(f != Mesh::null_face());
}
return 0;
}