Method MergeGrids

Filters/ParallelGeometry/vtkPDistributedDataFilter.cxx:4260–4316

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//------------------------------------------------------------------------------
vtkUnstructuredGrid* vtkPDistributedDataFilter::MergeGrids(vtkDataSet** sets, int nsets,
  int deleteDataSets, int useGlobalNodeIds, float pointMergeTolerance, int useGlobalCellIds)
{
  int i;

  if (nsets == 0)
  {
    return nullptr;
  }

  vtkUnstructuredGrid* newGrid = vtkUnstructuredGrid::New();
  // Any global ids should be consistent, so make sure they are passed.
  newGrid->GetPointData()->CopyGlobalIdsOn();
  newGrid->GetCellData()->CopyGlobalIdsOn();

  vtkMergeCells* mc = vtkMergeCells::New();
  mc->SetUnstructuredGrid(newGrid);

  mc->SetTotalNumberOfDataSets(nsets);

  vtkIdType totalPoints = 0;
  vtkIdType totalCells = 0;

  for (i = 0; i < nsets; i++)
  {
    totalPoints += sets[i]->GetNumberOfPoints();
    totalCells += sets[i]->GetNumberOfCells();
    // Only use global ids if they are available.
    useGlobalNodeIds = (useGlobalNodeIds && (sets[i]->GetPointData()->GetGlobalIds() != nullptr));
    useGlobalCellIds = (useGlobalCellIds && (sets[i]->GetCellData()->GetGlobalIds() != nullptr));
  }

  mc->SetTotalNumberOfPoints(totalPoints);
  mc->SetTotalNumberOfCells(totalCells);

  if (!useGlobalNodeIds)
  {
    mc->SetPointMergeTolerance(pointMergeTolerance);
  }
  mc->SetUseGlobalIds(useGlobalNodeIds);
  mc->SetUseGlobalCellIds(useGlobalCellIds);

  for (i = 0; i < nsets; i++)
  {
    mc->MergeDataSet(sets[i]);

    if (deleteDataSets)
    {
      sets[i]->Delete();
    }
  }

  mc->Finish();
  mc->Delete();

  return newGrid;
}