Method MarshalDataObject

Parallel/Core/vtkCommunicator.cxx:501–574

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

//------------------------------------------------------------------------------
int vtkCommunicator::MarshalDataObject(vtkDataObject* object, vtkCharArray* buffer)
{
  buffer->Initialize();
  buffer->SetNumberOfComponents(1);

  if (object == nullptr)
  {
    buffer->SetNumberOfTuples(0);
    return 1;
  }

  VTK_CREATE(vtkGenericDataObjectWriter, writer);

  vtkSmartPointer<vtkDataObject> copy;
  copy.TakeReference(object->NewInstance());
  copy->ShallowCopy(object);

  writer->SetFileTypeToBinary();
  // There is a problem with binary files with no data.
  if (vtkDataSet::SafeDownCast(copy) != nullptr)
  {
    vtkDataSet* ds = vtkDataSet::SafeDownCast(copy);
    if (ds->GetNumberOfCells() + ds->GetNumberOfPoints() == 0)
    {
      writer->SetFileTypeToASCII();
    }
  }
  writer->WriteToOutputStringOn();
  writer->SetInputData(copy);

  if (!writer->Write())
  {
    vtkGenericWarningMacro("Error detected while marshaling data object.");
    return 0;
  }
  const vtkIdType size = writer->GetOutputStringLength();
  if (object->GetExtentType() == VTK_3D_EXTENT)
  {
    // You would think that the extent information would be properly saved, but
    // no, it is not.
    int extent[6] = { 0, 0, 0, 0, 0, 0 };
    vtkRectilinearGrid* rg = vtkRectilinearGrid::SafeDownCast(object);
    vtkStructuredGrid* sg = vtkStructuredGrid::SafeDownCast(object);
    vtkImageData* id = vtkImageData::SafeDownCast(object);
    if (rg)
    {
      rg->GetExtent(extent);
    }
    else if (sg)
    {
      sg->GetExtent(extent);
    }
    else if (id)
    {
      id->GetExtent(extent);
    }
    char extentHeader[EXTENT_HEADER_SIZE];
    auto result =