Function ExecuteStructured

Filters/Geometry/vtkGeometryFilter.cxx:3294–3462

//------------------------------------------------------------------------------
template <typename TInputIdType>
int ExecuteStructured(vtkGeometryFilter* self, vtkDataSet* input, vtkPolyData* output,
  int* wholeExtent, vtkExcludedFaces<TInputIdType>* exc, bool* extractFace)
{
  vtkIdType numCells = input->GetNumberOfCells();
  vtkPointData* inPD = input->GetPointData();
  vtkCellData* inCD = input->GetCellData();
  vtkPointData* outPD = output->GetPointData();
  vtkCellData* outCD = output->GetCellData();

  // Setup processing
  bool mergePts = true; // implicit point representations require merging
  vtkPoints* inPts = nullptr;
  if (auto sgrid = vtkStructuredGrid::SafeDownCast(input))
  {
    inPts = sgrid->GetPoints();
    mergePts = self->GetMerging(); // may not be required for explicit
  }
  unsigned char* cellGhosts = nullptr;
  if (inCD)
  {
    if (auto ghosts = inCD->GetGhostArray())
    {
      cellGhosts = ghosts->GetPointer(0);
    }
  }

  // We can now extract the boundary topology. This works for all structured
  // types. Here we are only dealing with 3D structured datasets. The 2D cells
  // are handled as a general dataset.
  vtkNew<vtkCellArray> polys;
  output->SetPolys(polys);
  ThreadOutputType<TInputIdType> threads;

  outPD->CopyGlobalIdsOn();
  outCD->CopyGlobalIdsOn();

  ExtractCellBoundaries<TInputIdType>* extStr;
  // if extractFace are defined, it's an AMR block
  if (auto image = vtkImageData::SafeDownCast(input))
  {
    extStr = ExtractStructured<vtkImageData, TInputIdType>::Execute(
      self, image, wholeExtent, extractFace, mergePts, cellGhosts, exc, &threads);
  }
  else if (auto sGrid = vtkStructuredGrid::SafeDownCast(input))
  {
    extStr = ExtractStructured<vtkStructuredGrid, TInputIdType>::Execute(
      self, sGrid, wholeExtent, extractFace, mergePts, cellGhosts, exc, &threads);
  }
  else if (auto rGrid = vtkRectilinearGrid::SafeDownCast(input))
  {
    extStr = ExtractStructured<vtkRectilinearGrid, TInputIdType>::Execute(
      self, rGrid, wholeExtent, extractFace, mergePts, cellGhosts, exc, &threads);
  }
  else
  {
    vtkErrorWithObjectMacro(self, "Data type " << input->GetClassName() << "is not supported.");
    return 0;
  }