Method RequestData

Filters/CellGrid/vtkUnstructuredGridToCellGrid.cxx:191–275

}

int vtkUnstructuredGridToCellGrid::RequestData(
  vtkInformation* vtkNotUsed(request), vtkInformationVector** inInfo, vtkInformationVector* ouInfo)
{
  vtkSmartPointer<vtkPartitionedDataSetCollection> inputPDC;
  inputPDC = vtkPartitionedDataSetCollection::GetData(inInfo[0]);
  if (!inputPDC)
  {
    auto* input = vtkUnstructuredGrid::GetData(inInfo[0]);
    if (input)
    {
      inputPDC = vtkSmartPointer<vtkPartitionedDataSetCollection>::New();
      inputPDC->SetNumberOfPartitionedDataSets(1);
      inputPDC->SetPartition(0, 0, input);
    }
  }
  auto* output = vtkPartitionedDataSetCollection::GetData(ouInfo);
  if (!inputPDC)
  {
    vtkWarningMacro("Empty input or input of wrong type.");
    return 1;
  }
  if (!output)
  {
    vtkErrorMacro("Empty output.");
    return 0;
  }

  // Copy the input's hierarchical block arrangement if it exists:
  if (inputPDC->GetDataAssembly())
  {
    vtkNew<vtkDataAssembly> dataAssembly;
    dataAssembly->DeepCopy(inputPDC->GetDataAssembly());
    output->SetDataAssembly(dataAssembly);
  }

  // Look for annotations specifying DG cell-attributes.
  // this->AddAnnotatedAttributes(inputPDC);
  // Reset any annotations from the ustructured grid and re-ingest.
  this->Request->Annotations->Reset();
  this->Request->Annotations->FetchAnnotations(
    inputPDC->GetFieldData(), inputPDC->GetDataAssembly());

  // Iterate over partitioned datasets and turn unstructured grids
  // into cell grids.
  //
  // NB: We cannot use vtkPartitionedDataSetCollection::NewIterator()
  // to fetch an iterator because there is no mapping between that
  // iterator's flat index and the flat index of the parent node ID
  // in the vtkDataAssembly.
  // For instance, given a data assembly like this:
  //   + root 1
  //     + node 2 : dataset ids 0, 3
  //     + node 3 : dataset ids 1
  //       + node 4 : dataset ids 2
  //  When a composite iterator points to a dataset held inside
  //  dataset id 1 (itself a partitioned-dataset), there is no
  //  way to discover the flat index of dataset id 1 from the
  //  (non-partitioned) child dataset or the iterator.