if(GNURBS_ENABLE_TEST)
if(GNURBS_ENABLE_VTK_INTERFACE)
  add_subdirectory(curves)
  add_subdirectory(CoonsPatch)
  add_subdirectory(SurfaceOfRevolution)
endif(GNURBS_ENABLE_VTK_INTERFACE)
endif(GNURBS_ENABLE_TEST)