Tree stump highlighting missing

[ReaperSWE]

On this occasion, a birch tree stump wasn't being highlighted when hidden behind an apple tree. Forcing me to cut down the apple tree to remove the birch stump.

[loftar]

The problem with highlighting is that only the base coordinate of objects is checked for obstruction. Probably, that coordinate for the stump happened to be behind a pixel on the apple tree that wasn't opaque enough to be considered an obstruction. To be properly fixed, more than just the base coordinate should be checked, but I haven't yet figured out how to do that in a way that doesn't waste a ton of CPU time.

[ReaperSWE]

You could check the top left, base, and bottom right for obstruction, average the numbers, and draw the highlighting based on that?