[vtkusers] Help with vtkDataSetSurfaceFilter

[David Doria]

On Thu, May 27, 2010 at 5:38 AM, Adriano Gagliardi <agagliardi at ara.co.uk> wrote:
>
> Dear All,
>
> I'm trying to convert an unstructured surface mesh to poly data format with
> vtkDataSetSurfaceFilter, but I'm getting the following error:
>
> vtkStreamingDemandDrivenPipeline (0x1940cec0): Input port 0 of algorithm
> vtkDataSetSurfaceFilter(0x19460f70) has 0 connections but is not optional
>
> The code is as below:
>
> for ( int j = 0; j != input->GetNumberOfBlocks(); ++j ) {
>        vtkUnstructuredGrid* surf =
> vtkUnstructuredGrid::SafeDownCast(input->GetBlock(j));
>        vtkDataSetSurfaceFilter* polySurf = vtkDataSetSurfaceFilter::New();
>        polySurf->SetInput(surf);
>        polySurf->Update();
>        input->SetBlock(j, polySurf->GetOutput());
>        polySurf->Delete();
> }
>
> Cheers,
>
> Adriano
>
> p.s. I notice there is a problem with the VTK Examples website, otherwise
> I'd have had a look there first.
>
> ===================================
>
> Adriano Gagliardi MEng PhD

The kitware site seems to be back up.

You're usage seems to be identical to this:
http://www.vtk.org/Wiki/VTK/Examples/PolyData/DataSetSurfaceFilter

I'm not sure if 'surf' being NULL would product that error? Can you
try compiling a very short program in which you read a vtu and try to
run it through vtkDataSetSurfaceFilter? And in your current code, try

if(!surf)
 std::cout << "surf is NULL" << std::endl;

Thanks,

David