message: ENH: allow flip in projections' m_Direction in rtkprojectionmatrix
diff: @@ -96,9 +96,10 @@ int main(int argc, char * argv[])
  std::cerr << "This tool has been designed for 2D, i.e., with one row in the sinogram only." << std::endl;
  return EXIT_FAILURE;
  }
  - if(!reader->GetOutput()->GetDirection().GetVnlMatrix().is_identity ())
  + const OutputImageType::DirectionType dir = reader->GetOutput()->GetDirection();
  + if(itk::Math::abs(dir[0][0]) != 1. || itk::Math::abs(dir[1][1]) != 1.)
  {
  - std::cerr << "Projections with non-identity Direction is not handled." << std::endl;
  + std::cerr << "Projections with non-diagonal Direction is not handled." << std::endl;
  return EXIT_FAILURE;
  }
  