[vtkusers] VolumeRayCast with CellData

[Daniel Garcia]

Hello all,

I'm working in the creation of a 3D image from non parallel 2D images.
The fact is that, in vtkImageData, I need to work with CellData and
not PointData (for some specific algorithms) but as far as I've tried,
VolumeRayCast works only with PointData.

I've tried also the class vtkCellDataToPointData, but I didn't manage
to create an ImageData but a StructuredPoints that can't be rendered.

Thank you

Daniel