[Gmsh] Reclassify 2D does not work

[Martin Vymazal]

Hello Matthias,

  I don't know if there's a full documentation of ParaView plugins  
(they call them filters), but I simply go through the drop-down list  
of available filters (menu Filters->Alphabetical) and look if there's  
anything potentially useful for me. Most filters are available by  
default, you can control what is loaded at startup in Tools->Manage  
Plugins.

Most of the time, I use:
  - Transform to scale the mesh when I need it to be in different units
  - Clip to remove a part of the mesh
  - Extract cells by region (a bit similar to Clip, but preserves  
cells, does not cut through them)
  - Tetrahedralize (takes a hexa mesh and splits all elements into  
tetra elements)
  - Extract surface (similar to the skin plugin that prof. Geuzaine  
mentioned in his reply to my post)

I believe you can also use vtk as a library and link it to your own  
code to have all the filters available.

It's hard to process meshes with one opensource package, I usually use  
the combination Gmsh-Paraview-Meshlab. I like gmsh, but its gui  
becomes extremely slow with large meshes (say ~ 10^6 elements).  
ParaView is much more responsive.

Best regards,

   Martin Vymazal


Quoting "Zenker, Dr. Matthias" <Matthias.Zenker at erbe-med.com>:

> Hi Martin,
>
> I have read in your message below that one can modify a mesh with  
> ParaView. I use ParaView for postprocessing and didn't know that it  
> can also process meshes. Maybe this could help me to solve a meshing  
> problem I have since a long time which gmsh cannot solve. Could you  
> give me some indications where I can find information about  
> ParaView's mesh processing capabilities? Are there built-in filters  
> for that (which ones?), or did you need to build one yourself?
>
> Thank you for some hints,
>
> Matthias
>
> ----------------------------------------------------------------
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>> -----Ursprüngliche Nachricht-----
>> Von: Martin Vymazal [mailto:martin.vymazal at vki.ac.be]
>> Gesendet: Donnerstag, 4. April 2013 11:37
>> An: gmsh at geuz.org
>> Betreff: [Gmsh] Reclassify 2D does not work
>>
>> Dear gmsh developers,
>>
>>  I have a 3D flat plate grid  downloaded from here:
>> http://turbmodels.larc.nasa.gov/flatplate_grids.html (3D Plot3d  
>> grid, 2 x 545
>> x 385 points). I converted the grid to vtk and also split the hexahedra into
>> tetra using paraview. I am not able to reclassify the surface of  
>> the geometry
>> to create physical surfaces (to be able to set boundary conditions  
>> for my flow
>> solver). The 'Reclassify' button in the Reclassify2D dialog always remains
>> greyed out, no matter what I do. Is it a bug? If not, could you  
>> please tell me
>> the settings you use to reclassify the surface?
>>
>>  Best regards,
>>
>>    Martin Vymazal
>
>
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