Re: [MayaVi-users] Misunderstanding

[Prabhu R. <pra...@us...>]

>>>>> "MK" == Matthew Knepley <kn...@mc...> writes:

[...]
    MK> 3) Try to choose the PolyData Module, but it complains that
    MK>            it does not handle UnstructuredGrid

    MK> I thought the Filter would change the rep to PolyData, but
    MK> that is not happening somehow. I also misunderstand the "Show
    MK> Pipeline" command because I cannot understand the output. Any
    MK> suggestions here?
    MK>         I would be glad to send the new module or mesh if you
    MK> want.

Your understanding of the pipeline is perfectly ok.  I just wrote some
bad code in the PolyData module. :( The PolyData module was meant to
visualize data that originated from a file containing polydata.  An
unnecessary restriction since filters can change the data type.  I'll
fix this in CVS shortly.

However, I recommend that you use the SurfaceMap module instead of
PolyData in general.  SurfaceMap will work with any dataset and is
generally more used (and therefore better tested).  Using the
SurfaceMap you can view your data right now (no need to wait for
anon-CVS from SourceForge etc.).

Also note that you really don't need to write a new filter if its a
trivial one.  Simply use the UserDefined filter and enter the VTK
filter name.  Or from the command line like so:

 $ mayavi -d vtkbin.vtk -f UserDefined:vtkExtractEdges -m SurfaceMap

You might also want to try the vtkFeatureEdges filter like so:

 $ mayavi -d vtkbin.vtk -f PolyDataNormals -f \
 UserDefined:vtkFeatureEdges -m SurfaceMap

vtkFeatureEdges expects polydata so I add a PolyDataNormals filter
upstream.  If you look at Filters/PolyDataNormals.py you'll see that I
do some magic in the _set_input method to make sure that the data is
converted to polydata before processing.

cheers,
prabhu