Change interpolation method

[jamesobutler (James Butler)]

It appears you are trying to use PhongInterpolation for more realistic shading?

Slicer/Slicer/blob/0094e9a35bd266cc8b0e677858dabce797c9928f/Libs/MRML/Core/vtkMRMLDisplayNode.h#L54-L57

Have you tried the “Lights” module for various interactive lighting techniques for shading?

New module to customize lighting in 3D view

A new experimental module, “Lights”, was added to “Sandbox” extension that allows you to change lightkit parameters with a simple GUI. See a short demo video here: If we get the feedback that this module is useful then we’ll consider adding it to the Slicer core.