Unity Replay & Ghost System -- RC Racing

Recording and replaying ghost cars in Unity deterministically requires capturing vehicle transforms and dynamics at 50 Hz, bypassing PhysX non-determinism by using kinematic playback with Hermite interpolation for smooth visual motion.

The best way to compress racing replay data in Unity is using a pipeline of quantization, delta encoding, and DEFLATE compression, which can significantly reduce file sizes, for example compressing a 432 KB ghost file down to roughly 75 KB.

Cinemachine integration for ghost car playback provides dynamic viewing angles during kinematic replay. The system drives Cinemachine cameras alongside Hermite interpolation to render recorded vehicle transforms cinematically.

Yes, you can use async I/O to save and load ghost data in the background. This system implements asynchronous background I/O operations to prevent frame drops when reading or writing compressed replay files.

Yes, the Unity replay system includes anti-cheat validation. It implements validation mechanisms to verify the integrity of recorded ghost data, ensuring competitive racing replays remain untampered.

A limitation of state-based recording for racing replays is that it captures transforms at fixed intervals like 50 Hz rather than logging raw physics inputs, meaning playback relies on kinematic interpolation rather than real-time physics simulation.