Method RequestData

Filters/Extraction/vtkExtractBlock.cxx:98–148

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

//------------------------------------------------------------------------------
int vtkExtractBlock::RequestData(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  auto input = vtkDataObjectTree::GetData(inputVector[0], 0);
  auto output = vtkDataObjectTree::GetData(outputVector, 0);
  if (this->Indices->find(0) != this->Indices->end())
  {
    // trivial case.
    output->CompositeShallowCopy(input);
    return 1;
  }

  // pruning is unnecessary for vtkPartitionedDataSetCollection and hence we
  // skip it.
  const bool prune =
    vtkPartitionedDataSetCollection::SafeDownCast(input) ? false : (this->PruneOutput != 0);

  output->CopyStructure(input);

  vtkSet activeIndices(*this->Indices);

  // Copy selected blocks over to the output.
  vtkDataObjectTreeIterator* iter = input->NewTreeIterator();
  iter->VisitOnlyLeavesOff();
  iter->SkipEmptyNodesOff();
  for (iter->InitTraversal(); !iter->IsDoneWithTraversal() && !activeIndices.empty();
       iter->GoToNextItem())
  {
    if (this->CheckAbort())
    {
      break;
    }
    if (activeIndices.find(iter->GetCurrentFlatIndex()) != activeIndices.end())
    {
      activeIndices.erase(iter->GetCurrentFlatIndex());
      this->CopySubTree(iter, output, input, activeIndices);

      if (prune)
      {
        // add a "hint" to the output to help identify visited nodes.
        output->GetMetaData(iter)->Set(DONT_PRUNE(), 1);
      }
    }
  }
  iter->Delete();
  if (prune)
  {
    this->Prune(output);
  }
  return 1;
}

//------------------------------------------------------------------------------
bool vtkExtractBlock::Prune(vtkDataObject* branch)