    streamers = vtkStreamTracer()
    # streamers.DebugOn()
    streamers.SetInputConnection(reader.GetOutputPort())
    streamers.SetSourceConnection(line1.GetOutputPort())
    streamers.SetMaximumPropagation(maxTime)
    streamers.SetInitialIntegrationStep(0.2)
--
    streamers = vtkStreamTracer()
    streamers.SetInputConnection(reader.GetOutputPort())
    streamers.SetSourceConnection(psource.GetOutputPort())
    # streamers.SetMaximumPropagationUnitToTimeUnit()
    streamers.SetMaximumPropagation(100.0)
    # streamers.SetInitialIntegrationStepUnitToCellLengthUnit()
--
    streamers = vtkStreamTracer()
    streamers.SetInputConnection(pl3d.GetOutputPort())

    # streamers SetSource [rake GetOutput]
    streamers.SetSourceConnection(seedsComp.GetOutputPort())
    streamers.SetMaximumPropagation(250)
--
    streamers = vtkStreamTracer()
    streamers.SetInputConnection(pl3d.GetOutputPort())

    # streamers SetSource [rake GetOutput]
    streamers.SetSourceConnection(seedsComp.GetOutputPort())
    streamers.SetMaximumPropagation(250)
--
        streamers = vtkStreamTracer()
        streamers.SetInputConnection(pl3d.GetOutputPort())

        # streamers SetSource [rake GetOutput]
        streamers.SetSourceConnection(rake.GetOutputPort())
        streamers.SetMaximumPropagation(250)
--
    streamers = vtkStreamTracer()
    streamers.SetInputConnection(reader.GetOutputPort())
    streamers.SetSourceConnection(seeds.GetOutputPort())
    streamers.SetMaximumPropagation(500)
    streamers.SetMinimumIntegrationStep(0.1)
    streamers.SetMaximumIntegrationStep(1.0)
--
    streamer = vtkStreamTracer()
    streamer.SetInputConnection(reader.GetOutputPort())
    streamer.SetStartPosition(0.1, 2.1, 0.5)
    streamer.SetMaximumPropagation(500)
    streamer.SetInitialIntegrationStep(0.05)
    streamer.SetIntegrationDirectionToBoth()
--
    streamer = vtkStreamTracer()
    streamer.SetInputData(pl3d_output)
    streamer.SetSourceData(seeds)
    streamer.SetMaximumPropagation(100)
    streamer.SetInitialIntegrationStep(0.2)
    streamer.SetIntegrationDirectionToForward()
--
    streamer2 = vtkStreamTracer()
    streamer2.SetInputData(pl3d_output)
    streamer2.SetSourceData(seeds2)
    streamer2.SetMaximumPropagation(100)
    streamer2.SetInitialIntegrationStep(0.2)
    streamer2.SetIntegrationDirectionToForward()
--
    streamers = vtkStreamTracer()
    # streamers.DebugOn()
    streamers.SetInputConnection(reader.GetOutputPort())
    streamers.SetSourceConnection(line.GetOutputPort())
    streamers.SetMaximumPropagation(maxTime)
    streamers.SetInitialIntegrationStep(.5)
--
    streamline = vtkStreamTracer()
    streamline.SetInputData(pl3d.GetOutput().GetBlock(0))
    streamline.SetSourceConnection(seeds.GetOutputPort())
    streamline.SetMaximumPropagation(200)
    streamline.SetInitialIntegrationStep(.2)
    streamline.SetIntegrationDirectionToForward()
