Angle measurements using LOS thread

It would be great if the LOS thread allowed you to measure not only the distance but also the angle between two pieces, as drawn from the measuring piece.

The angle might be defined in terms of 360 degrees, or it could be just a coarse measurement of firing arc. For example, the circle around a piece could simply be defined as four firing arcs, each 90 degrees, and the thread would indicate which of the arcs it crossed.