Listing all objects affected by direct lighting

I’m looking into finding the easiest way to test for an actor (or rather, multiple actors) overlapping with light from light sources like movable spotlights, basically an implementation of the On Actor Begin Overlap event for “collision” with lighting. There are few other similar threads ([here][1] or [here][2]) that ask the same question, but the proposed solutions look too cumbersome and expensive to use on large scale.

Instead of relying on collision and tracing, isn’t there any way to test for something like brightness level adjustment instead? Naturally, all the the objects affected by lighting do get identified and listed to be processed by said lighting somewhere in the code. Imagine the most basic example with a pitch black level (no ambient or any other lighting), a single spotlight, and a few box actors. Some of the boxes are directly lit, some stay in shadow of other boxes, and some are completely unlit by the spotlight. Isn’t there a simpler way to get an array of all the objects that receive any brightness adjustments (partial or full) as the result of the lighting, instead of endlessly running multiple collision checks, then individual tracing checks and whatnot? This has been gnawing at me for a while now, so any insight into the subject will be much appreciated.

Image: cheaply identifying boxes #1 and #2 as lit.