The cylinder, arrow, cone, pyramid, sphere, ring, box, and
ellipsoid objects (but not curve or convex) can be rotated about a specified
origin:
object.rotate(angle=pi/4., axis=axis, origin=pos)
The rotate function applies a transformation to the specified
object (sphere, box, etc.). The transformation is a rotation of angle
radians, counterclockwise around the line defined by origin
and origin+axis. By default, rotations are
around the object's own pos and axis.