Method ExecuteDataWithInformation

IO/MPIImage/vtkMPIImageReader.cxx:365–491

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

//------------------------------------------------------------------------------
void vtkMPIImageReader::ExecuteDataWithInformation(vtkDataObject* output, vtkInformation* outInfo)
{
#ifdef VTK_USE_MPI_IO
  vtkMPIController* MPIController = vtkMPIController::SafeDownCast(this->Controller);
  if (!MPIController)
  {
    this->Superclass::ExecuteDataWithInformation(output, outInfo);
    return;
  }

  vtkImageData* data = this->AllocateOutputData(output, outInfo);

  if (!this->FileName && !this->FilePattern && !this->FileNames)
  {
    vtkErrorMacro("Either a valid FileName, FileNames, or FilePattern"
                  " must be specified.");
    return;
  }

  // VTK stores images in traditional "right handed" coordinates.  That is, the
  // origin is in the lower left corner.  Many images, especially those with RGB
  // colors, have the origin in the upper right corner.  In this case, we have
  // to flip the y axis.
  vtkTransform* saveTransform = this->Transform;
  if (!this->FileLowerLeft)
  {
    vtkTransform* newTransform = vtkTransform::New();
    if (this->Transform)
    {
      newTransform->Concatenate(this->Transform);
    }
    else
    {
      newTransform->Identity();
    }
    newTransform->Scale(1.0, -1.0, 1.0);
    this->Transform = newTransform;
  }

  // Get information on data partition requested.
  int inExtent[6];
  vtkIdType inIncrements[3];
  data->GetExtent(inExtent);
  data->GetIncrements(inIncrements);
  vtkDataArray* outputDataArray = data->GetPointData()->GetScalars();
  vtkIdType numValues =
    (outputDataArray->GetNumberOfComponents() * outputDataArray->GetNumberOfTuples());

  outputDataArray->SetName(this->ScalarArrayName);

  vtkDebugMacro("Reading extent: " << inExtent[0] << ", " << inExtent[1] << ", " << inExtent[2]
                                   << ", " << inExtent[3] << ", " << inExtent[4] << ", "
                                   << inExtent[5]);

  // Respect the Transform.
  int outExtent[6];
  vtkIdType outIncrements[3];
  this->ComputeInverseTransformedExtent(inExtent, outExtent);