Method SplitMesh

Filters/General/vtkIntersectionPolyDataFilter.cxx:455–633

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//------------------------------------------------------------------------------
int vtkIntersectionPolyDataFilter::Impl ::SplitMesh(
  int inputIndex, vtkPolyData* output, vtkPolyData* intersectionLines)
{
  vtkPolyData* input = this->Mesh[inputIndex];
  IntersectionMapType* intersectionMap = this->IntersectionMap[inputIndex];
  vtkCellData* inCD = input->GetCellData();
  vtkCellData* outCD = output->GetCellData();
  vtkIdType numCells = input->GetNumberOfCells();
  vtkIdType cellIdX = 0;

  //
  // Process points
  //
  vtkIdType inputNumPoints = input->GetPoints()->GetNumberOfPoints();
  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
  points->Allocate(100);
  output->SetPoints(points);

  //
  // Split intersection lines. The lines structure is constructed
  // using a vtkPointLocator. However, some lines may have an endpoint
  // on a cell edge that has no neighbor. We need to duplicate a line
  // point in such a case and update the point ID in the line cell.
  //
  vtkSmartPointer<vtkPolyData> splitLines = vtkSmartPointer<vtkPolyData>::New();
  splitLines->DeepCopy(intersectionLines);

  vtkPointData* inPD = input->GetPointData();
  vtkPointData* outPD = output->GetPointData();
  outPD->CopyAllocate(inPD, input->GetNumberOfPoints());

  // Copy over the point data from the input
  for (vtkIdType ptId = 0; ptId < inputNumPoints; ptId++)
  {
    double pt[3];
    input->GetPoints()->GetPoint(ptId, pt);
    output->GetPoints()->InsertNextPoint(pt);
    outPD->CopyData(inPD, ptId, ptId);
    this->BoundaryPoints[inputIndex]->InsertValue(ptId, 0);
  }

  // Copy the points from splitLines to the output, interpolating the
  // data as we go.
  for (vtkIdType id = 0; id < splitLines->GetNumberOfPoints(); id++)
  {
    double pt[3];
    splitLines->GetPoint(id, pt);
    vtkIdType newPtId = output->GetPoints()->InsertNextPoint(pt);

    // Retrieve the cell ID from splitLines
    vtkIdType cellId = this->PointCellIds[inputIndex]->GetValue(id);

    double closestPt[3], pcoords[3], dist2, weights[3];
    int subId;
    vtkCell* cell = input->GetCell(cellId);
    cell->EvaluatePosition(pt, closestPt, subId, pcoords, dist2, weights);
    outPD->InterpolatePoint(input->GetPointData(), newPtId, cell->PointIds, weights);
    this->BoundaryPoints[inputIndex]->InsertValue(newPtId, 0);