[Paraview] Combination of polygonal-data and unstructured grid?

[Stefan Melber]

Hi Armin,

sounds thats the thing i searched for! Will check it out today and see 
if it does the job. Is there a demo-xml file around with such polyhedral 
cells?

Best regards and thank you,

       Stefan


> Hi Stefan,
>
> If I understand your problem correctly, then you are looking for
> polyhedral cells (i.e. N face cells, where each face is a M edge
> polygon). Polyhedral cells are commonly used in Computational Fluid
> Dynamics codes, as e.g. OpenFOAM, and VTK/ParaView support them already
> for quite some time (i.e. since around 2010), see [1] for more details.
>
>> My problem is now i have a set of complex shaped volumes (dual-grid
>> data) which cannot be found in the list of cell types for
>> unstructured grid data. Therefore i use the polygonal data and color
>> each cell with one color. Of course for further analysis (e.g.
>> integration of the cell volumes, volume gradient and so on) i need a
>> way to give a set of (closed surface) poly-data elements a kind
>> connection to form a volume to handle them together.
> In which file format do you store your data?
>
> For example, the unstructured VTK XML format [2] has support for
> polyhedral cells. An alternative would be the XDMF file format [3] to
> which I recently added polyhedral cell support [4,5]. Please note that
> the latest release versions of VTK (7.0) or ParaView (5.1) don't support
> the polyhedral cells in XDMF yet, but the nightly builds and the
> upcoming releases (i.e. VTK 7.1 and ParaView 5.2) will have this feature.
>
> Cheers,
> Armin
>
>
> [1] http://www.vtk.org/Wiki/VTK/Polyhedron_Support
> [2] http://www.vtk.org/Wiki/VTK_XML_Formats
> [3] http://www.xdmf.org
> [4] 
> https://gitlab.kitware.com/xdmf/xdmf/commit/0a9fbd0590dff8a677c86754169cd2ccd72fe4b1
> [5] 
> https://gitlab.kitware.com/vtk/vtk/commit/802c9b61de28e560c2659d2af76660bbb49c68be
>
>