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

[Stefan Melber]

Hi Armin,

thank you  - thats what i searched for ...

      Stefan
> Hi Stefan,
>
> IIRC there is a .vtu file containing polyhderal cells in the VTK DATA
> repository.
>
> Otherwise, I attached a .xmf and a .vtu file containing each containing
> identical data, i.e. 2 hexahedral and 2 polyhderal cell.
> Please note that the white-space in these files has no meaning, and that
> for the .xmf file you need a recent ParaView nightly build.
>
> Best regards,
> Armin
>
>
>
>
>
> On 09/27/2016 07:42 AM, Stefan Melber wrote:
>> 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 
>>>
>>>
>>>
>>>
>>