Method DivideCells

IO/Parallel/vtkPChacoReader.cxx:300–376

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

}
//------------------------------------------------------------------------------
int vtkPChacoReader::DivideCells(
  vtkMultiProcessController* contr, vtkUnstructuredGrid* output, int source)
{
  int retVal = 1;

  int i = 0;

  int nprocs = contr->GetNumberOfProcesses();
  int myrank = contr->GetLocalProcessId();

  vtkUnstructuredGrid* mygrid = nullptr;

  if (source == myrank)
  {
    vtkIdType ntotalcells = output->GetNumberOfCells();
    vtkIdType nshare = ntotalcells / nprocs;
    vtkIdType leftover = ntotalcells - (nprocs * nshare);

    vtkIdType startId = 0;

    for (i = 0; i < nprocs; i++)
    {
      if (!retVal && (i != myrank))
      {
        this->SendGrid(contr, i, nullptr); // we failed
        continue;
      }

      vtkIdType ncells = ((i < leftover) ? nshare + 1 : nshare);

      vtkIdType endId = startId + ncells - 1;

      vtkUnstructuredGrid* ug = this->SubGrid(output, startId, endId);

      if (i != myrank)
      {
        retVal = this->SendGrid(contr, i, ug);
        ug->Delete();
      }
      else
      {
        mygrid = ug;
      }
      startId += ncells;
    }
  }
  else
  {
    mygrid = this->GetGrid(contr, source);
    if (mygrid == nullptr)
    {
      retVal = 0;
    }
  }

  int vote = 0;
  contr->Reduce(&retVal, &vote, 1, vtkCommunicator::SUM_OP, 0);
  contr->Broadcast(&vote, 1, 0);