NullPointerException in Gridded3DSet.makeIsoLines()

I must have been asking VisAD to display contours of some unfriendly
data, but I'd expect a healthier response:

java.lang.NullPointerException
        at visad.Gridded3DSet.makeIsoLines(Gridded3DSet.java:1705)
        at visad.ShadowType.makeContour(ShadowType.java:3553)
        at
visad.java3d.ShadowTypeJ3D.makeContour(ShadowTypeJ3D.java:329)
        at
visad.ShadowFunctionOrSetType.doTransform(ShadowFunctionOrSetType.java:2074)
        at
visad.java3d.ShadowFunctionOrSetTypeJ3D.doTransform(ShadowFunctionOrSetTypeJ3D.java:100)
        at
visad.java3d.ShadowFunctionOrSetTypeJ3D.recurseRange(ShadowFunctionOrSetTypeJ3D.java:986)
        at
visad.ShadowFunctionOrSetType.doTransform(ShadowFunctionOrSetType.java:2914)
        at
visad.java3d.ShadowFunctionOrSetTypeJ3D.doTransform(ShadowFunctionOrSetTypeJ3D.java:100)
        at
visad.java3d.DefaultRendererJ3D.doTransform(DefaultRendererJ3D.java:99)
        at visad.java3d.RendererJ3D.doAction(RendererJ3D.java:180)
        at visad.DisplayImpl.doAction(DisplayImpl.java:1546)
        at visad.ActionImpl.run(ActionImpl.java:303)
        at visad.util.ThreadPool$ThreadMinnow.run(ThreadPool.java:95)

Also, the "please wait" is left on.

Cheers,
Doug

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| Doug Lindholm, Software Engineer          |  E-mail: lind@xxxxxxxx   |
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