Very simply, dynamic lights with a limited cone of illumination. Suitable for flashlights, spotlights, headlamps, etc. These would use the same lighting models (standard or attenuated) and args (RGB + radius/intensity) as existing dynamic lights. An additional arg would be used for the spread of the beam, similar to a camera's FOV angle. The actor angle/pitch would be used to point the light (angle 0 being east and pitch 0 being horizontally level, of course). In the unlikely event masks/projectors/shapes are possible, those would use the actor roll of course. Otherwise perhaps roll could be re-purposed to define the spread or softness of the illumination cone.
From a couple discussions in Discord I get the impression this should be, while not trivial, certainly not impossible or extremely difficult and (in addition to global directional illumination) would fulfill another long-awaited lighting options for modders.
