Interesting historical annotation

[SheepNine]

First off, kudos for such a well-written book. I have thoroughly enjoyed reading it.

Just wanted to offer up something that you could add for history buffs: in chapter 20, you mention the corner case of two entities in separate cells of a grid partition. It turns out that this bug exists in the 1993 classic Doom! See http://games.moria.org.uk/doom/research/shooting-through-things for the technical details.

[munificent]

Oh, this is fascinating, thank you!