[vtkusers] QVTKWidget + volume misbehavior

[clinton at elemtech.com]

Does image point to the output of another filter?  In which case the execution 
of the pipeline will overwrite anything you do to image.  Maybe you intend to 
delete the filter and keep the image?

Clint

On Wednesday 12 November 2008 4:42:23 am Dominik Szczerba wrote:
> I am doing something as trivial as:
>
> 	// record existing spacing
> 	image->GetSpacing(old_spacing);
>
> 	// modify it
> 	image->SetSpacing(new_spacing);
> 	image->Modified();
>
> 	// refresh display
> 	vtkWidget->GetRenderWindow()->Render();
>
> 	// debug
> 	image->GetSpacing(current_spacing);
>
>
> which behaves correctly, with current_spacing = new_spacing and my
> outline actor responding to the changes.
>
> The moment I call:
>
> 	ren1->AddVolume(volume); // volume is representation of image
>
> I can properly see my volume only before calling Render():
> current_spacing gets reset back to old_spacing right after.
>
> 1) Am I doing something obviously wrong (like I am not allowed to modify
> a registered volume)
> 2) What is caching the original image properties and why?
>
> Thanks for any hints,
> Dominik