how to draw a a simple cross line in vtkresliceimageviewer

hi, all
i am a vtk beginner. i am trying to draw a simple crossline in the vtk example of fourpane view’s vtkresliceimageviwer pane to indicate the other two view’s slice index. but i don`t find a right way to solve the problem. anyone can give me sugessions or directions ? thanks very much.

You need to use a vtkLineSource to get the polydata and put it on a mapper, about the four planes I don’t know I guess they would be acotrs