Method TransformData

IO/MPIImage/vtkMPIImageReader.cxx:300–355

This method could be made a lot more efficient.

#ifdef VTK_USE_MPI_IO
// This method could be made a lot more efficient.
void vtkMPIImageReader::TransformData(vtkImageData* data)
{
  if (!this->Transform)
    return;

  vtkDataArray* fileData = data->GetPointData()->GetScalars();
  vtkDataArray* dataData = fileData->NewInstance();
  dataData->SetName(fileData->GetName());
  dataData->SetNumberOfComponents(fileData->GetNumberOfComponents());
  dataData->SetNumberOfTuples(fileData->GetNumberOfTuples());

  int dataExtent[6];
  data->GetExtent(dataExtent);

  int fileExtent[6];
  this->ComputeInverseTransformedExtent(dataExtent, fileExtent);

  vtkIdType dataMinExtent[3];
  vtkIdType fileMinExtent[3];
  vtkIdType dataExtentSize[3];
  vtkIdType fileExtentSize[3];
  for (int i = 0; i < 3; i++)
  {
    dataMinExtent[i] = std::min(dataExtent[2 * i], dataExtent[2 * i + 1]);
    fileMinExtent[i] = std::min(fileExtent[2 * i], fileExtent[2 * i + 1]);
    dataExtentSize[i] = std::abs(dataExtent[2 * i + 1] - dataExtent[2 * i]) + 1;
    fileExtentSize[i] = std::abs(fileExtent[2 * i + 1] - fileExtent[2 * i]) + 1;
  }

  for (vtkIdType file_k = 0; file_k < fileExtentSize[2]; file_k++)
  {
    for (vtkIdType file_j = 0; file_j < fileExtentSize[1]; file_j++)
    {
      for (vtkIdType file_i = 0; file_i < fileExtentSize[0]; file_i++)
      {
        double fileXYZ[3];
        fileXYZ[0] = file_i + fileMinExtent[0];
        fileXYZ[1] = file_j + fileMinExtent[1];
        fileXYZ[2] = file_k + fileMinExtent[2];
        double dataXYZ[3];
        this->Transform->TransformPoint(fileXYZ, dataXYZ);
        vtkIdType data_i = static_cast<vtkIdType>(dataXYZ[0]) - dataMinExtent[0];
        vtkIdType data_j = static_cast<vtkIdType>(dataXYZ[1]) - dataMinExtent[1];
        vtkIdType data_k = static_cast<vtkIdType>(dataXYZ[2]) - dataMinExtent[2];

        vtkIdType fileTuple = ((file_k * fileExtentSize[1] + file_j) * fileExtentSize[0]) + file_i;
        vtkIdType dataTuple = ((data_k * dataExtentSize[1] + data_j) * dataExtentSize[0]) + data_i;

        dataData->SetTuple(dataTuple, fileTuple, fileData);
      }
    }
  }

  data->GetPointData()->SetScalars(dataData);
  dataData->Delete();
}
#else  // VTK_USE_MPI_IO
void vtkMPIImageReader::TransformData(vtkImageData*)