MPR shows the instrument from three angles but, crucially, the thickness of the view can be varied. This allows you to search for tiny details such as worm channels. The axis can also be changed. That’s really useful because all the surfaces of the violin are curved.
See how well the worm channels show up. Only a few exit holes were visible on the inside surface of the back.
The arching profiles can be shown in any plane and the thicknesses measured accurately.
This is perfect for copying an instrument or planning arching corrections.