Method extractFaceMesh

src/Mesh.cc:100–333

}

int Mesh::extractFaceMesh(const TopoDS_Face& face, bool qualityNormals)
{

  if (face.IsNull()) {
    StdFail_NotDone::Raise("Face is Null");
  }
  auto& hashMap = this->_faceHashMap;
  int hash = face.HashCode(std::numeric_limits<int>::max());
  // find hash in edgehash.push_back(hash);
  if (hashMap.end() != hashMap.find(hash)) {
    return 0;
  }

  hashMap[hash] = (uint32_t)this->_faceRanges.size();
  this->_faceRanges.push_back((uint32_t)this->_triangles.size());

  TopLoc_Location loc;
  occHandle(Poly_Triangulation) triangulation = BRep_Tool::Triangulation(face, loc);
  if (triangulation.IsNull()) {
    StdFail_NotDone::Raise("No triangulation created");
  }

  bool reversed = (face.Orientation() == TopAbs_REVERSED);
  int nb_points = triangulation->NbNodes();

  gp_Trsf tr = loc;
  std::vector<uint32_t> translationTable;
  translationTable.reserve(nb_points);

  std::vector<uint32_t> normalTranslationTable;
  normalTranslationTable.reserve(nb_points);

  // ------------------------------------------------------------------------------
  // import face points into index 
  // ------------------------------------------------------------------------------
  const TColgp_Array1OfPnt&   nodes = triangulation->Nodes();
  Coord3f vert;
  double x, y, z;
  for (int i = 1; i <= nb_points; i++) {
    const gp_Pnt& pnt = nodes(i);
    x = pnt.X();
    y = pnt.Y();
    z = pnt.Z();
    tr.Transforms(x, y, z);
    vert.x = (float)x;
    vert.y = (float)y;
    vert.z = (float)z;
    uint32_t index = push_point(vert);
    translationTable.push_back(index);
  }

  // ------------------------------------------------------------------------------
  // import vertex normal
  // ------------------------------------------------------------------------------
  std::vector<gp_Vec> local_normals;
  local_normals.reserve(nb_points);

  if (!qualityNormals) {