btw the site now has instant replay seeking. i optimized it really well. it works by pre-simulating the run, which just takes a second since the sim is 900x realtime, then it also notes when the decals appear. in the game decals keep piling up during the run (shells, corpses, blood, explosions), so you can’t easily take them back.
it makes state checkpoints, or keyframes if you wish, as well as more sparse ground checkpoints. then when you seek it reads the closest previous ones, does a little bit a simulation and re-applies the missing decals since the last snapshot.
it all works really fast, scrubbing anywhere takes 2-5ms, and you can get the full replay compressed to just tens or a hundred kilobytes since it’s just inputs which is enough for deterministic simulation.