This example demonstrates how to do clipped volume rendering
The 3DHEAD model is clipped with a sphere. The clipping model is a standard OpenInventor scene graph under a SoVolumeClippingGroup. Jittering and preintergration are applied to the final rendering in order to decrease slicing effect thanks to the SoVolumeRenderingQuality node.
SoVolumeClippingGroup SoVolumeRenderingQuality