[Paraview] Pruned output for extract block

[Utkarsh Ayachit]

Paul,

If you don't want the ExtractBlock filter to prune the output, you can
always simply uncheck the "Prune Output" checkbox.

Utkarsh

On Thu, Feb 18, 2010 at 9:45 AM, Paul Edwards <paul.m.edwards at gmail.com> wrote:
> Hi,
> What is the reason for pruning the structure in the "Extract Block" filter
> when there is only one child item?  I output the following structure from
> the custom reader:
>
> output (multi-block dataset)
>
> zone 1 (multi-block dataset)
>
> volume (unstructured grid)
> boundaries (multi-block dataset)
>
> blade (poly data)
> hub (poly data)
> case (poly data)
>
> zone 2 (multi-block dataset)
>
> volume (unstructured grid)
> boundaries (multi-block dataset)
>
> blade (poly data)
> hub (poly data)
> case (poly data)
>
> If I were to extract both the blades then the resulting structured would be:
>
> output (multi-block dataset)
>
> blade (poly data)
> blade (poly data)
>
> This has now lost all the information from the original structure.
> Commenting out the section for the case when there is only one child item
> fixes this for me:
> 8<--------------------------------------------------------------------------------------------------
> Index: ./VTK/Graphics/vtkExtractBlock.cxx
> ===================================================================
> RCS file: /cvsroot/ParaView3/ParaView3/VTK/Graphics/vtkExtractBlock.cxx,v
> retrieving revision 1.6
> diff -r1.6 vtkExtractBlock.cxx
> 239,251c239,251
> <         vtkMultiBlockDataSet* prunedBlock =
> vtkMultiBlockDataSet::SafeDownCast(block);
> <         if (prunedBlock && prunedBlock->GetNumberOfBlocks()==1)
> <           {
> <           // shrink redundant branches.
> <           clone->SetBlock(index, prunedBlock->GetBlock(0));
> <           if (prunedBlock->HasMetaData(static_cast<unsigned int>(0)))
> <             {
> <             clone->GetMetaData(index)->Copy(prunedBlock->GetMetaData(
> <                 static_cast<unsigned int>(0)));
> <             }
> <           }
> <         else
> <           {
> ---
>> //        vtkMultiBlockDataSet* prunedBlock =
>> vtkMultiBlockDataSet::SafeDownCast(block);
>> //        if (prunedBlock && prunedBlock->GetNumberOfBlocks()==1)
>> //          {
>> //          // shrink redundant branches.
>> //          clone->SetBlock(index, prunedBlock->GetBlock(0));
>> //          if (prunedBlock->HasMetaData(static_cast<unsigned int>(0)))
>> //            {
>> //            clone->GetMetaData(index)->Copy(prunedBlock->GetMetaData(
>> //                static_cast<unsigned int>(0)));
>> //            }
>> //          }
>> //        else
>> //          {
> 257c257
> <           }
> ---
>> //          }
> -------------------------------------------------------------------------------------------------->8
> Could this case be removed in the main CVS or is there a good reason for
> keeping it?  (maybe an option could be added for it....)
> Thanks,
> Paul
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Please keep messages on-topic and check the ParaView Wiki at:
> http://paraview.org/Wiki/ParaView
>
> Follow this link to subscribe/unsubscribe:
> http://www.paraview.org/mailman/listinfo/paraview
>
>