Function SynchronizeBlocks

IO/ParallelNetCDF/vtkPSLACReader.cxx:154–182

============================================================================= Make sure that each process has the same number of blocks in the same position. Assumes that all blocks are unstructured grids.

// Make sure that each process has the same number of blocks in the same
// position.  Assumes that all blocks are unstructured grids.
static void SynchronizeBlocks(vtkMultiBlockDataSet* blocks, vtkMultiProcessController* controller,
  vtkInformationIntegerKey* typeKey)
{
  unsigned long localNumBlocks = blocks->GetNumberOfBlocks();
  unsigned long numBlocks;
  controller->AllReduce(&localNumBlocks, &numBlocks, 1, vtkCommunicator::MAX_OP);
  if (blocks->GetNumberOfBlocks() < numBlocks)
  {
    blocks->SetNumberOfBlocks(numBlocks);
  }

  for (unsigned int blockId = 0; blockId < numBlocks; blockId++)
  {
    vtkDataObject* object = blocks->GetBlock(blockId);
    if (object && !object->IsA("vtkUnstructuredGrid"))
    {
      vtkGenericWarningMacro(<< "Sanity error: found a block that is not an unstructured grid.");
    }
    int localBlockExists = (object != nullptr);
    int globalBlockExists = 0;
    controller->AllReduce(&localBlockExists, &globalBlockExists, 1, vtkCommunicator::LOGICAL_OR_OP);
    if (!localBlockExists && globalBlockExists)
    {
      vtkNew<vtkUnstructuredGrid> grid;
      blocks->SetBlock(blockId, grid);
      blocks->GetMetaData(blockId)->Set(typeKey, 1);
    }
  }
}

//=============================================================================
// Structures used by ReadMidpointCoordinates to store and transfer midpoint