Developing Your Own Replay System / SO

One approach (low memory)

• your game has to be deterministic.
• it records the initial state of the game systems on the first frame, and only the player input during gameplay.
• quantize inputs to lower # of bits. Ie. represent floats within various ranges (eg. [0, 1] or [-1 , 1] range within less bits. Quantized inputs have to be obtained during actual game play too.
• use a single bit to determine whether an input stream has new data. Since some streams won’t change frequently, this exploits temporal coherence in the inputs.