[vtkusers] missing points in polydata

[David E DeMarle]

You've given your extracted vtkPolyData cells but you haven't copied
over the points that those cells refer to.

Also, why not use a threshold or selection filter to do this?

David E DeMarle
Kitware, Inc.
R&D Engineer
21 Corporate Drive
Clifton Park, NY 12065-8662
Phone: 518-881-4909


On Wed, Aug 1, 2012 at 6:08 AM, Gonzalo Amadio <gonzaloamadio at gmail.com> wrote:
> Hello everyone. I have a polydata with scalars ( 0,1 or 2 ) in the cells.
> I want to extract all the cells with scalar 1.
> Finally, when I try to print the number of points in the extracted polydata,
> it gives me 0 . What I am missing here?
> Should I construct the points set explicitly?
>
>> polydata->GetPolys()->InitTraversal();
>>
>>
>> int i = 0;
>>
>>
>>
>> while ( polydata->GetPolys()->GetNextCell ( npts, pts ) != 0 )
>> {
>> if (cellScalarsPolydata->GetValue( i ) == 1) // if cell scalar == 1, get
>> it.
>> {
>> extractedCellArray->InsertNextCell(3);
>> extractedCellArray->InsertCellPoint(pts[0]);
>> extractedCellArray->InsertCellPoint(pts[1]);
>> extractedCellArray->InsertCellPoint(pts[2]);
>> }
>> i++;
>> }
>>
>>
>>
>> vtkPolyData* extractedPolyData = vtkPolyData::New();
>> extractedPolyData->SetPolys(extractedCellArray);
>> extractedPolyData->BuildCells();
>>
>>
>>
>> std::cout << "num points" << extractedPolyData->GetNumberOfPoints() <<
>> std::endl; // This gives me 0
>
>
>
> --
> --------
> Gonzalo Amadio
>
>
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