@quartata I'm working on
a clone of bsdgames's atc
(an "air traffic control" simulation/game). It's an array of pointers to all planes currently on the radar. I know that the change in x of every plane is always either -1, 0, or 1, so if I cache the sorted result via pointers to the actual plane, I don't have to do as much work. (Yes, technically the planes aren't
always ≤ 2 from their actual spot, but only in very rare edge cases are they not).