    hedgehog = vtkHedgeHog()
    hedgehog.SetInputData(sgrid)
    hedgehog.SetScaleFactor(0.1)

    sgridMapper = vtkPolyDataMapper()
    sgridMapper.SetInputConnection(hedgehog.GetOutputPort())
--
    hhog = vtkHedgeHog()
    hhog.SetInputConnection(reader.GetOutputPort())
    hhog.SetScaleFactor(0.3)

    lut = vtkLookupTable()
    # lut.SetHueRange(.667, 0.0)
