position
Position of the light source relative to lit (extruded) geometries, in r radial coordinate, a azimuthal angle, p polar angle where r indicates the distance from the center of the base of an object to its light, a indicates the position of the light relative to 0 degree (0 degree when light.anchor is set to viewport corresponds to the top of the viewport, or 0 degree when light.anchor is set to map corresponds to due north, and degrees proceed clockwise), and p indicates the height of the light (from 0 degree, directly above, to 180 degree, directly below).
This is an Expression representation of "position".