A protocol for distributed collision detection

Abstract

Scalability of multiplayer games can be improved by client-side processing of game actions. Consistency becomes a concern, however, in the case of unpredictable but important events such as object interactions. We propose here a new motion-lock protocol for distributed collision detection and resolution. The motion-lock protocol improves performance of motion prediction by giving stations time to communicate and agree on the detected collisions. This reduces the divergence of distributed object states and post-collision trajectories. Offline and online simulation results show the motion-lock protocol results in qualitative and quantitative improvements to consistency, with negligible network impact and a minimal sacrifice in the responsiveness of player controls. Our design can be used to hide latency and reduce server load in current multiplayer online games, improving scalability and furthering fully distributed designs.