[vtkusers] Depth peeling a volume

[David Brayford]

Does anyone know how to show the inside of a volume scan in VTK as I
can display the data but can only see the outside shell when I want to
be able to view the inside. I can view the correct structures in a
DICOM viewer, but can only display a cylinder in VTK.

The data is a vtkVolume and can generate a correct DRR within ITK
using thresholding, bujt I don't know how to do this in VTK.

I tried this, but it didn't work

	volumeActor = vtkVolume::New();
	renderer->AddVolume(volumeActor);

	vtkVolumeProperty *prop = vtkVolumeProperty::New();
	vtkPiecewiseFunction *opacity = vtkPiecewiseFunction::New();
	opacity->AddPoint(20, 0);
	opacity->AddPoint(20, 0);
	opacity->AddPoint(20, 0);
	prop->SetScalarOpacity( opacity );

	// connect up the volume to the property and the mapper
	volumeActor->SetProperty( prop );


Thanks
David