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<DIV><FONT size=2 face=Arial>Hi,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>If my recollection is correct, in VTK 4.2, filters
which took vtkDataSet as input and produced an output type = input type, warned
when the input type changed because the output had to be deleted and re-created
to match the input.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>e.g.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial> f =
vtkMergeDataObjectFilter::New();</FONT></DIV>
<DIV><FONT size=2 face=Arial> f->SetInput( vtkPolyData
);</FONT></DIV>
<DIV><FONT size=2 face=Arial>
f->SetInput( vtkUnstructuredGrid ); // delete 'old' vtkPolyData
output and create 'new' vtkUnstructuredGrid output</FONT></DIV>
<DIV><FONT size=2 face=Arial>
<P>In VTK 5.4, these filters are now derived from vtkDataSetAlgorithm. The
problem (I think) I have is, doing</P><FONT size=2>
<DIV><FONT size=2 face=Arial> f->SetInput( vtkPolyData
);</FONT></DIV>
<DIV><FONT size=2 face=Arial>
f->SetInput( vtkUnstructuredGrid );</FONT></DIV>
<DIV> vtkDataSet* ds1 = f->GetOutput();</DIV>
<DIV> f->Update();</DIV>
<DIV>
<DIV> vtkDataSet* ds2 = f->GetOutput();</DIV>
<DIV> </DIV>
<DIV>gives 2 different objects for ds1 & ds2 (ds1 is corrupt). Also, I
cannot see any warning that the output from the first SetInput() will be
deleted.</DIV>
<DIV> </DIV>
<DIV>Can anyone confirm if this is the expected behaviour?</DIV>
<DIV> </DIV>
<DIV>Many thanks for any help.</DIV>
<DIV> </DIV>
<DIV>John.</DIV></DIV></FONT></FONT></DIV></BODY></HTML>