Method RequestDataInternal

Filters/ParallelGeometry/vtkPDistributedDataFilter.cxx:322–501

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

//------------------------------------------------------------------------------
int vtkPDistributedDataFilter::RequestDataInternal(vtkDataSet* input, vtkUnstructuredGrid* output)
{
  TimeLog timer("RequestDataInternal", this->Timing);
  (void)timer;

  this->NextProgressStep = 0;
  int progressSteps = 5 + this->GhostLevel;
  if (this->ClipCells)
  {
    progressSteps++;
  }

  this->ProgressIncrement = 1.0 / (double)progressSteps;

  this->UpdateProgress(this->NextProgressStep++ * this->ProgressIncrement);
  this->SetProgressText("Begin data redistribution");

  if (this->NumProcesses == 1)
  {
    this->SingleProcessExecute(input, output);
    this->UpdateProgress(1.0);
    return 1;
  }

  // This method requires an MPI controller.

  int aok = 0;

  if (vtkMPIController::SafeDownCast(this->Controller))
  {
    aok = 1;
  }

  if (!aok)
  {
    vtkErrorMacro(<< "vtkPDistributedDataFilter multiprocess requires MPI");
    return 1;
  }

  // Stage (0) - If any processes have 0 cell input data sets, then
  //   spread the input data sets around (quickly) before formal
  //   redistribution.

  int duplicateCells;
  vtkDataSet* splitInput = this->TestFixTooFewInputFiles(input, duplicateCells);

  if (splitInput == nullptr)
  {
    return 1; // Fewer cells than processes - can't divide input
  }

  this->UpdateProgress(this->NextProgressStep++ * this->ProgressIncrement);
  this->SetProgressText("Compute spatial partitioning");

  // Stage (1) - use vtkPKdTree to...
  //   Create a load balanced spatial decomposition in parallel.
  //   Create a table assigning regions to processes.
  //