[vtk-developers] Which class to derive from for filter with input: PolyData, output: Graph

[Jeff Baumes]

> In fact, stepping through with the debugger I realized that it is
> never even going into FillInputPortInformation() or RequestData(),
> which seems very strange?
>
> The error is:
> vtkStreamingDemandDrivenPipeline (0x8571e78): Algorithm
> vtkGraphAlgorithm(0x856fee8) returned failure for request:
> vtkInformation (0x8572160)

Try debugging a bit further to see exactly the request type that is
failing. e.g. you can put a breakpoint in
vtkGraphAlgorithm::ProcessRequest() to see which type of requests are
happening and which one fails (returns 0).

Jeff