Physics playback

A run records and plays back, two engines run the same game in rollback exchanging only inputs, and a digest per tick catches a desync.

• A snapshot restores a tick and the deterministic simulation re-runs the same inputs. Node ids are stable across spawns and re-runs, and scripts see rollback::input and rollback::is_resimulating.

• A peer publishes a tick's hash once every player's input for it has arrived. A desync names the tick.

• Transport runs over WebSockets, and over QUIC datagrams through balaur_webtransport, where a lost input costs a misprediction. balaur_http, balaur_websocket and balaur_webtransport are one crate each, behind their own features.

• Delay, jitter and datagram loss can be set on every session link, from the editor's settings.

  

Networking · Determinism · Balaur for multiplayer