Method Collapse

Common/DataModel/vtkReebGraph.cxx:2428–2624

------------------------------------------------------------------------------

//------------------------------------------------------------------------------
void vtkReebGraph::Implementation::Collapse(vtkIdType startingNode, vtkIdType endingNode,
  vtkReebLabelTag startingLabel, vtkReebLabelTag endingLabel)
{

  int L0, L0n, L1, L1n;
  int cont[3] = { 0, 0, 0 }, Case;

  if (startingNode == endingNode)
    return;

  vtkReebNode* nstart = this->GetNode(startingNode);
  vtkReebNode* nend = this->GetNode(endingNode);

  if (!vtkReebGraphIsSmaller(this, startingNode, endingNode, nstart, nend))
  {
    vtkReebGraphSwapVars(int, startingNode, endingNode);
    vtkReebGraphSwapVars(vtkReebNode*, nstart, nend);
  }

  L0 = FindUpLabel(startingNode, startingLabel);
  L1 = FindUpLabel(startingNode, endingLabel);

  while (true)
  {
    int A0 = this->GetLabel(L0)->ArcId;
    vtkReebArc* a0 = this->GetArc(A0);
    int A1 = this->GetLabel(L1)->ArcId;
    vtkReebArc* a1 = this->GetArc(A1);

    vtkReebNode* down0 = this->GetNode(a0->NodeId0);
    vtkReebNode* up0 = this->GetNode(a0->NodeId1);
    vtkReebNode* up1 = this->GetNode(a1->NodeId1);

    /* it is the same arc, no semplification is done */
    if (A0 == A1)
    {
      Case = 0;
      L0n = this->GetLabel(L0)->VNext;
      L1n = this->GetLabel(L1)->VNext;
    }
    /* there are two arcs connecting the same start-end node */
    else if (A0 != A1 && a0->NodeId1 == a1->NodeId1)
    {
      Case = 1;
      vtkReebGraphRemoveUpArc(this, a0->NodeId0, A1);
      vtkReebGraphRemoveDownArc(this, a0->NodeId1, A1);

      for (int Lcur = this->GetArc(A1)->LabelId0; Lcur; Lcur = this->GetLabel(Lcur)->HNext)
      {
        this->GetLabel(Lcur)->ArcId = A0;
      }

      this->GetLabel(this->GetArc(A1)->LabelId0)->HPrev = this->GetArc(A0)->LabelId1;
      this->GetLabel(this->GetArc(A0)->LabelId1)->HNext = this->GetArc(A1)->LabelId0;
      this->GetArc(A0)->LabelId1 = this->GetArc(A1)->LabelId1;

      this->GetArc(A1)->LabelId0 = 0;
      this->GetArc(A1)->LabelId1 = 0;