[vtkusers] vtkSeedWidget and vtkImageViewer2 bug in visualization?

[Nicolas Rannou]

On 04/13/2010 10:53 AM, John Drescher wrote:
> On Tue, Apr 13, 2010 at 9:49 AM, Nicolas Rannou
> <nicolas_rannou at hms.harvard.edu>  wrote:
>    
>> Hello,
>>
>> I'm experimenting some troubles using vtkSeedWidget.
>>
>> I visualize a volume (*.mhd) in a vtkImageViewer2.
>> Then I use vtkSeedWidget to select some points through the volume.
>>
>> The problem is that when I select one point in one slice, then move to
>> another slice to select another point, I can see the actor of the first
>> selected point even if I am not on the same slice anymore.
>> If I move further, the first point will not be visible after some more
>> slices...
>> The coordinates (real world coordinates) of all the created points are good.
>>
>> The problem must be in the visualization/actors somewhere...
>>
>> I tried to use vtkConstrainedPointHandleRepresentation and
>> vtkImageActorPointPlacer without success.
>>
>> Did somebody already face this issue or have any advice?
>>
>>
>> Thanks for your help,
>>
>>      
> You need to either reimplement the seed widget to handle slices (I
> have done this) or create a seed widget for each slice and then use
> the callback mechanism to hide and restore seed widgets when the slice
> changes.
>
> John
>    

Hi John,

Thanks for the fast answer.

Is you code available as part of VTK or an open source project?
Does your reimplemented seed widget works in the same way as you 
suggested (

create a seed widget for each slice and then use
the callback mechanism to hide and restore seed widgets when the slice
changes

)

Or is it a different approach?

I would like to avoid creating  a seed widget for each slice, since I 
have 3 rendering windows to visualize a 3d volume through different 
views. (create 500 + 500 +500 seed widgets?)

And I'm not totally satisfied with this kind of solution because I feel 
like creating a widget for each slice doesn't solve the problem but just 
avoid it doing some tricks, which  would prefer not to do if possible.

Thanks,

     Nicolas