Hello fellow multiplayer devs!
I’ve been working on a 2D physics engine for a synchronous RTS game. It uses fixed point math with no arbitrary rounding so theoretically, it’ll turn up with the same results on all computers given the same input. Note that this is theory right now - as I continue to develop this engine and my RTS game, this theory will be proven.
Many games such as Call of duty, Halo, Starcraft, Warcraft, and Command and Conquer use synchronous simulations for efficiency in bandwidth and replay systems. If you’re interested, check out the Work In Progress thread here: DPhysics: Deterministic 2D Physics Engine - Community Showcases - Unity Discussions.