Mesh_feature_extractor ne renvoie pas la bordure correcte

Question

Je ne comprends peut-être pas comment la bordure Mesh_feature_extractor fonctionne. J'utilise un cube parfait avec 8 sommets, quand j'appelle get_nb_borders() il renvoie 1, ce qui me semble faux (peut-être que ma compréhension de 'Border' est fausse). Quelqu'un peut-il expliquer ce qu'est une frontière?

std::vector<Vector3> tempVertices; 
    tempVertices.push_back(Vector3(-50, 50, -50)); 
    tempVertices.push_back(Vector3(-50, 50, 50)); 
    tempVertices.push_back(Vector3(50, 50, 50)); 
    tempVertices.push_back(Vector3(50, 50, -50)); 

    tempVertices.push_back(Vector3(-50, -50, -50)); 
    tempVertices.push_back(Vector3(-50, -50, 50)); 
    tempVertices.push_back(Vector3(50, -50, 50)); 
    tempVertices.push_back(Vector3(50, -50, -50)); 

    std::vector<int32> tempIndices; 
    tempIndices.push_back(0); tempIndices.push_back(2); tempIndices.push_back(1); 
    tempIndices.push_back(0); tempIndices.push_back(3); tempIndices.push_back(2); 

    tempIndices.push_back(4); tempIndices.push_back(6); tempIndices.push_back(5); 
    tempIndices.push_back(4); tempIndices.push_back(7); tempIndices.push_back(6); 

    tempIndices.push_back(4); tempIndices.push_back(3); tempIndices.push_back(0); 
    tempIndices.push_back(4); tempIndices.push_back(7); tempIndices.push_back(3); 

    tempIndices.push_back(7); tempIndices.push_back(2); tempIndices.push_back(3); 
    tempIndices.push_back(7); tempIndices.push_back(6); tempIndices.push_back(2); 

    tempIndices.push_back(6); tempIndices.push_back(1); tempIndices.push_back(2); 
    tempIndices.push_back(6); tempIndices.push_back(5); tempIndices.push_back(1); 

    tempIndices.push_back(5); tempIndices.push_back(0); tempIndices.push_back(1); 
    tempIndices.push_back(5); tempIndices.push_back(4); tempIndices.push_back(0); 

    typedef Polyhedron::HalfedgeDS HalfedgeDS; 

    Polyhedron mesh; 
    CGALTriangleBuilder<HalfedgeDS> triangle(tempVertices, tempIndices); 
    mesh.delegate(triangle); 

    typedef CGAL::Parameterization_polyhedron_adaptor_3<Polyhedron> Parameterization_polyhedron_adaptor; 
    Parameterization_polyhedron_adaptor mesh_adaptor(mesh); 

    // Helper class to compute genus or extract borders 
    typedef CGAL::Parameterization_mesh_feature_extractor<Parameterization_polyhedron_adaptor> Mesh_feature_extractor; 


    // Extract mesh borders and compute genus 
    Mesh_feature_extractor feature_extractor(mesh_adaptor); 
    int nb_borders = feature_extractor.get_nb_borders(); 
    int genus = feature_extractor.get_genus(); 

Answer 1

Mon mauvais 1 face du cube était dans le sens horaire et de repos étaient ... antihoraire