Method RequestData

Infovis/Core/vtkExtractSelectedGraph.cxx:120–444

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

//------------------------------------------------------------------------------
int vtkExtractSelectedGraph::RequestData(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  vtkGraph* input = vtkGraph::GetData(inputVector[0]);
  vtkSelection* inputSelection = vtkSelection::GetData(inputVector[1]);
  vtkAnnotationLayers* inputAnnotations = vtkAnnotationLayers::GetData(inputVector[2]);
  vtkGraph* output = vtkGraph::GetData(outputVector);

  if (!inputSelection && !inputAnnotations)
  {
    vtkErrorMacro("No vtkSelection or vtkAnnotationLayers provided as input.");
    return 0;
  }

  vtkSmartPointer<vtkSelection> selection = vtkSmartPointer<vtkSelection>::New();
  int numSelections = 0;
  if (inputSelection)
  {
    selection->DeepCopy(inputSelection);
    numSelections++;
  }

  // If input annotations are provided, extract their selections only if
  // they are enabled and not hidden.
  if (inputAnnotations)
  {
    for (unsigned int i = 0; i < inputAnnotations->GetNumberOfAnnotations(); ++i)
    {
      vtkAnnotation* a = inputAnnotations->GetAnnotation(i);
      if ((a->GetInformation()->Has(vtkAnnotation::ENABLE()) &&
            a->GetInformation()->Get(vtkAnnotation::ENABLE()) == 0) ||
        (a->GetInformation()->Has(vtkAnnotation::ENABLE()) &&
          a->GetInformation()->Get(vtkAnnotation::ENABLE()) == 1 &&
          a->GetInformation()->Has(vtkAnnotation::HIDE()) &&
          a->GetInformation()->Get(vtkAnnotation::HIDE()) == 1))
      {
        continue;
      }
      selection->Union(a->GetSelection());
      numSelections++;
    }
  }

  // Handle case where there was no input selection and no enabled, non-hidden
  // annotations
  if (numSelections == 0)
  {
    output->ShallowCopy(input);
    return 1;
  }

  // Convert the selection to an INDICES selection
  vtkSmartPointer<vtkSelection> converted;
  converted.TakeReference(vtkConvertSelection::ToIndexSelection(selection, input));
  if (!converted)
  {
    vtkErrorMacro("Selection conversion to INDICES failed.");
    return 0;