Method ExtractSurface

Filters/Geometry/vtkExplicitStructuredGridSurfaceFilter.cxx:102–247

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

//------------------------------------------------------------------------------
int vtkExplicitStructuredGridSurfaceFilter::ExtractSurface(
  vtkExplicitStructuredGrid* input, vtkPolyData* output)
{
  vtkIdType numPts = input->GetNumberOfPoints();
  vtkIdType numCells = input->GetNumberOfCells();

  if (numCells == 0)
  {
    return 1;
  }

  vtkDebugMacro(<< "Executing explicit structured grid surface filter");

  vtkPointData* pd = input->GetPointData();
  vtkCellData* cd = input->GetCellData();
  vtkPointData* outputPD = output->GetPointData();
  vtkCellData* outputCD = output->GetCellData();

  vtkNew<vtkIdTypeArray> originalCellIds;
  if (this->PassThroughCellIds)
  {
    originalCellIds->SetName(this->GetOriginalCellIdsName());
    originalCellIds->SetNumberOfComponents(1);
    originalCellIds->Allocate(numCells);
    outputCD->AddArray(originalCellIds.GetPointer());
  }
  vtkNew<vtkIdTypeArray> originalPointIds;
  if (this->PassThroughPointIds)
  {
    originalPointIds->SetName(this->GetOriginalPointIdsName());
    originalPointIds->SetNumberOfComponents(1);
    originalPointIds->Allocate(numPts);
    outputPD->AddArray(originalPointIds.GetPointer());
  }

  vtkNew<vtkIdList> cellIds;
  vtkUnsignedCharArray* connectivityFlags = nullptr;

  const char* facesConnectivityFlagsArrayName = input->GetFacesConnectivityFlagsArrayName();
  if (facesConnectivityFlagsArrayName)
  {
    connectivityFlags = vtkUnsignedCharArray::SafeDownCast(
      input->GetCellData()->GetAbstractArray(facesConnectivityFlagsArrayName));
  }
  if (!connectivityFlags)
  {
    vtkErrorMacro("Make sure Connectivity Flags have been computed before using this filter");
    return 0;
  }

  vtkPoints* points = input->GetPoints();
  vtkCellArray* cells = input->GetCells();
  if (!points || !cells)
  {
    return 1;
  }

  // Allocate