[vtkusers] ImageData WholeExtent/Dimensions problem

[Lisa Sobierajski Avila]

Hello John,

The Extent is the part actually updated, which comes from the UpdateExtent 
which is either set explicitly, or is set by an upstream source / data 
object. How is your filter getting the Update call - directly, or from 
upstream? What is your UpdateExtent? If the UpdateExtent is 0 -1 0 -1 0 -1 
then the filter should automatically change this to the whole extent. There 
were some changes to this logic from 2.4 to 3.1.

Lisa


At 07:54 PM 10/5/2000, John Biddiscombe wrote:
>I'm averaging some 2D data and producing a final value which in
>some cases consists of a single pixel.
>
>Setting
>data->SetWholeExtent(0,0,0,0,0,0);
>data->SetDimensions(1,1,1);
>used to set the dimensions of the image to
>1,1,1 as expected
>but now the Extent is being set to
>0,-1,0,-1,0,-1
>and dimensions are returned as 0,0,0
>
>causing most grievious access violations when allocating scalars
>and writing to memory.
>
>Has someone changed the functionality to handle UpdateExtents and
>streaming issues differently (invalid update extents)?
>
>thanks
>
>John B
>
>
>
>_______________________________________________
>This is the private VTK discussion list.
>Please keep messages on-topic. Check the FAQ at: 
><http://public.kitware.com/cgi-bin/vtkfaq>
>Follow this link to subscribe/unsubscribe:
>http://public.kitware.com/mailman/listinfo/vtkusers