Method RequestData

Filters/Generic/vtkGenericClip.cxx:125–369

------------------------------------------------------------------------------ Clip through data generating surface.

// Clip through data generating surface.
//
int vtkGenericClip::RequestData(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  // get the info objects
  vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
  vtkInformation* outInfo = outputVector->GetInformationObject(0);

  // get the input and output
  vtkGenericDataSet* input =
    vtkGenericDataSet::SafeDownCast(inInfo->Get(vtkDataObject::DATA_OBJECT()));
  vtkUnstructuredGrid* output =
    vtkUnstructuredGrid::SafeDownCast(outInfo->Get(vtkDataObject::DATA_OBJECT()));

  if (input == nullptr)
  {
    return 1;
  }

  vtkUnstructuredGrid* clippedOutput = this->GetClippedOutput();

  vtkIdType numPts = input->GetNumberOfPoints();
  vtkIdType numCells = input->GetNumberOfCells();
  vtkPointData* outPD = output->GetPointData();
  vtkCellData* outCD[2];
  vtkIdType npts = 0;
  const vtkIdType* pts;
  int cellType = 0;
  int j;
  vtkIdType estimatedSize;
  vtkUnsignedCharArray* types[2];
  int numOutputs = 1;
  vtkGenericAdaptorCell* cell;

  outCD[0] = nullptr;
  outCD[1] = nullptr;

  vtkDebugMacro(<< "Clipping dataset");

  // Initialize self; create output objects
  //
  if (numPts < 1)
  {
    vtkErrorMacro(<< "No data to clip");
    return 1;
  }

  if (!this->ClipFunction && this->GenerateClipScalars)
  {
    vtkErrorMacro(<< "Cannot generate clip scalars if no clip function defined");
    return 1;
  }

  // allocate the output and associated helper classes
  estimatedSize = numCells;
  estimatedSize = estimatedSize / 1024 * 1024; // multiple of 1024
  estimatedSize = std::max<vtkIdType>(estimatedSize, 1024);

  vtkPoints* newPoints = vtkPoints::New();