[Paraview-developers] MultiBlockDataSet rendering error with parallel Paraview

[Utkarsh Ayachit]

Prashant,

If I understand correctly, you're creating a vtkMultiBlockDataSet
(MBD) on each ParaView rank for each timestep. What is the structure
of this MBD on all ranks for a specific timestep? Structure implies
the multiblock tree i.e, number of blocks in this MBD and its children
and so on. ParaView/VTK requires that the structure is identical on
all ranks. It's okay to have NULL datasets on ranks where there's no
data for a specific leaf node in the multblock tree.


Utkarsh

On Wed, Aug 5, 2015 at 12:17 PM, Prashant V <prashant.v at quest-global.com> wrote:
> Hi,
>
> I am relatively new to paraview and developing a co-processing framework for
> a client.
> I am facing problem when running paraview in parallel mode.
>
> I have developed a paraview source plugin which collects data from each
> iteration of solver simulation and renders in paraview.
> When simulation is run in parallel mode with n processes, source plugin
> collects n multiBlockDataSets.
> If paraview is also running in parallel mode with n processes, source plugin
> code assigns one multiblock to each paraview process.
> However rendering fails in this scenario with error message:
>
> 'vtkMultiBlockDataSet (0x1860afe0): Structure does not match. You must use
> CopyStructure before calling this method'
>
> While exploring this error, some old paraview e-mails suggested to apply d3
> filter to each dataset.
>
> I applied d3 filter to each multiblock as below:
>
> VTK_CREATE(vtkDistributedDataFilter, d3);
>
> d3->AddInputData(multiblock);
> d3->UpdateInformation();
> exec = static_cast<vtkStreamingDemandDrivenPipeline*>(d3->GetExecutive());
> exec->SetUpdateExtent(exec->GetOutputInformation(), piece, numPieces, 1); //
> 1 -> ghostlevel
> d3->Update();
>
> newMultiBlock->ShallowCopy(d3->GetOutput());
>
>
> However this leads to new set of errors:
>
> vtkPKdTree (0xea7b440): (process 0) VolumeBounds - degenerate volume
> vtkDistributedDataFilter (0xe7b6480): Unable to build k-d tree structure
> vtkDistributedDataFilter (0xe7b6480): vtkDistributedDataFilter::Execute k-d
> tree failure
>
> Can anyone advice here what could be going wrong? MultiBlockDataSets render
> perfectly with sequential run of paraview.
>
> Thanks,
> Prashant
> ---Disclaimer------------------------------ This e-mail contains PRIVILEGED
> AND CONFIDENTIAL INFORMATION intended solely for the use of the
> addressee(s). If you are not the intended recipient, please notify the
> sender by e-mail and delete the original message. Opinions, conclusions and
> other information in this transmission that do not relate to the official
> business of QuEST Global and/or its subsidiaries, shall be understood as
> neither given nor endorsed by it. Any statements made herein that are
> tantamount to contractual obligations, promises, claims or commitments shall
> not be binding on the Company unless followed by written confirmation by an
> authorized signatory of the Company.
> -----------------------------------------------------------------------------------
>
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Search the list archives at:
> http://markmail.org/search/?q=Paraview-developers
>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/paraview-developers
>