[vtkusers] How do you turn on/off a pipeline?

[Charles Law]

prabhu,

In Tcl and empty string is interpreted as NULL.  I do not know about python.

If I have my python syntax correct, this should work.


>c = vtkContourFilter()
># do something with c
>...
># turn c off
save = c.GetOutput()
>  dummy = vtkPolyData()
>c.SetOutput(dummy)
># do whatever
>...
># turn it back on
>c.SetOutput(save)


Charles.




At 11:24 PM 7/5/00 +0530, you wrote:
>hi,
>
>         Thanks for all the tips.  But how does one do all this with
>python?  Using SetInput(0) results in an exception (SystemError).  Or
>should I just do something like
>
>c = vtkContourFilter()
># do something with c
>...
># turn c off
>s = vtkPolyDataReader()
>c.SetInput(s.GetOutput())
># do whatever
>...
># turn it back on
>c.SetInput(correct_object.GetOutput())
>
>Is there no other way to do this?  Or am I missing something?
>
>prabhu
>
> >>>>> "Law" == Charles Law <charles.law at kitware.com> writes:
>
>     Law> Setting the output of a source/filter to NULL will have the
>     Law> same effect.  Turn the pipeline back on by setting the output
>     Law> back to the old value.
>
>     Law> Charles.
>
>     Law> At 10:57 AM 7/5/00 +0100, John Biddiscombe wrote:
>     >> >A simple question: > How does one turn on or off a particular
>     >> VTK pipeline?  Or how >does one disconnect a pipeline??
>     >>
>     >> Write a simple filter which takes an input, and generates an
>     >> output, all it does is copystructure from input to output and
>     >> pass point and cell data, override the update mechanism so that
>     >> when flag=false, output doesn't get updated, when flag=true it
>     >> acts as usual.
>     >>