Checking if 2 objects are in the same grid cell (before checking proximity) is a great way to improve performance. However it does have a flaw which I'm seeing frequently enough to be annoying:
If 2 small speeding objects are near the edge of a cell, their areas may be colliding but because they're in different cells the collision won't be detected.
Does anyone have a simple solution for this? I'll admit it's an unlikely occurance but in the style of my game it's not THAT rare and I don't want any misses. Thanks!