Do replay files require consistency or can you spawn new units from the ether as required? I think you could get a system that would get the broad strokes unit placement correct, but having a shot-for-shot perfect replication seems impossible.

Replay files are streams of the orders given by players. They generally can't do anything which would be impossible in game.

I suppose that makes sense for a deterministic engine. That way you have an ordered steam of actions with only one way to execute them.

I was wondering how you could possibly sync up something like a Carrier that has multiple fighters.

> I was wondering how you could possibly sync up something like a Carrier that has multiple fighters.

Same way as everything else - you play out the simulation and see what happens. The behavior of the interceptors is as deterministic as any other unit. (They just happen to not be directly commandable by their owner.)

No, I get that. The pondering was before I knew it was a recording of actions. Once you know that, it is a fully self-contained box with external nudges from the players which get inserted into the simulation.

Not feasible. The VODs are from a spectator's perspective; there's a lot of action happening "off camera" (like players building units) which affects what's seen on camera later, and which would be extremely difficult to reconstruct from what's visible.