Povray in action.
The Viviani-Body is the intersection of a sphere with a cylinder, where the cylinder is tangential to both the sphere’s boundary and an axis going through the sphere’s centerpoint.
The Povray-animation shows this body rotating. It is a Full-HD-video with 50 fps, 18000 frames (so the duration is 6 minutes) and its bitrate is 0.8 MBit/s.
$\mbox{The Viviani-Body}$