[vtk-developers] UPDATE_EXTENT not updating after change to WHOLE_EXTENT

[Bill McGrory]

I  have a pipeline for displaying structured zones within a GUI. These 
zone's have multiple grid refinement levels or sequences. The beginning 
of the pipeline is a source which creates a vtkStructuredGrid.

When I interactively change the sequence level the source gets a call to 
update the pipeline where I need to change the vtkStructuredGrid to 
represent a different sequence level (so my grid grid dimensions will 
double or halve, for example)

This process worked (by accident perhaps) in versions of VTK prior to 6.

Thanks
Bill


On 01/04/2016 11:08 AM, Berk Geveci wrote:
> Hey Bill,
>
> The very short (and annoying) answer is that VTK does not currently 
> support varying WHOLE_EXTENT().
>
> However, there are ways of getting around this. But before I get into 
> those, can you describe how/where you change the whole extent? As part 
> of a time update? By setting some data member on the reader?
>
> Best,
> -berk
>
> On Wed, Dec 30, 2015 at 3:24 PM, Bill McGrory <mcgrory at aerosoftinc.com 
> <mailto:mcgrory at aerosoftinc.com>> wrote:
>
>      I am having difficulty porting some code from VTK 5 to 6.
>
>     I have a custom algorithm for creating  a vtkStructuredGrid as the
>     source for my pipeline, so my class inherits
>     vtkStructuredGridAlgorithm
>
>     my pipeline simply connects the vtkStructuredGridAlgorithm to a
>     vtkGeometryFilter which is mapped with a vtkPolyDataMapper
>
>     I want my source to correctly render a structured grid which
>     changes dimensions dynamically within my application.
>
>     My problem is that  if I originally set up the grid with say
>     extents of 0 --99, 0-->99,  0-->99, and then change the extents to
>     0--49, 0-49,0-49 through a call to Update, then I get a VTK error
>     message from
>
>
>     ERROR: In
>     VTK-6.2.0/Common/ExecutionModel/vtkStreamingDemandDrivenPipeline.cxx,
>     line 860
>     vtkCompositeDataPipeline (0xb4561f0): The update extent specified
>     in the information for output port 0 on algorithm
>     SurfaceSNodeSource(0xb455750) is 0 80 0 32 0 0, which is outside
>     the whole extent 0 40 0 16 0 0.
>     (This is in VerifyOutputInformation) called before the
>     RequestUpdateExtent for my algorithm.
>
>     I don't quite understand the propagation of the UPDATE_EXTENT
>     information up the pipeline, but if I set the UPDATE_EXTENT to
>     WHOLE_EXTENT
>
>     in vtkGeometryFilter::RequestUpdateExtent
>
>     then the error goes away.
>     Also, at the time of calling
>     vtkGeometryFilter::RequestUpdateExtent, the UPDATE_EXTENT is still
>     set at the old value, while the WHOLE_EXTENT has been correctly
>     updated/propagated from upstream.
>
>     Is this a bug, or do I need to change something in my
>     vtkStructuredGridAlgorithm to cause the UPDATE_EXTENT to be reset
>     at the origin downstream?
>
>     Thanks
>
>     Bill
>     _______________________________________________
>     Powered by www.kitware.com <http://www.kitware.com>
>
>     Visit other Kitware open-source projects at
>     http://www.kitware.com/opensource/opensource.html
>
>     Search the list archives at:
>     http://markmail.org/search/?q=vtk-developers
>
>     Follow this link to subscribe/unsubscribe:
>     http://public.kitware.com/mailman/listinfo/vtk-developers
>
>

-- 
Dr. William D. McGrory    AeroSoft, Inc.
mcgrory at aerosoftinc.com   Suite 1400
(540) 557-1904            2000 Kraft Drive
(540) 557-1919 (FAX)      Blacksburg, VA 24060

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtk-developers/attachments/20160104/18972365/attachment.html>