By pure chance, I am watching Edge of Tomorrow as we type. (It's a Tom Cruise time loop movie, if you haven't seen it.)

A game with a story line built around that concept would be very interesting, for sure. However, the old Sierra adventure games came to mind, specifically Space Quest and Leisure Suit Larry, where you just had to keep trying different things until you didn't die. It was fun back in the day, but it got old really quick.

Implemention in a sports game is a cool idea, though.

that only really works with deterministic systems though. You could do that with a 6502 or simple systems because you could perfectly predict what the state of the system would be in just by replaying inputs. everything up to predicting all cache misses.

consider a badly written game on a modern console (remember that save states should work for any game) in which physics is tied to framerate. Follow the chain... framerate depends on system speed... which, indirectly depends on the ambient temperature (a console running in a hot climate would throttle earlier than one running in an air conditioned cool room). And because modern systems execute more than one process, it also depends on what else is running (were you downloading a game in the background, slowing down the game ever so slightly?) or unpredictable things such as interrupts on certain system timers. And the list goes on and on. Even if the game didn't have physics depending on framerate, differing deltaTime on each frame means different floating point rounding errors happen, which could accumulate over time.

So in this case, replaying inputs does not get you the exact state. you were in. there are just too many variables.

system state is not the same as a save file. System state is the cpu registers, the process' entire memory space (because you don't know what the game might do at any point) gpu context, etc.

edit: example: the save file for older games was measured in bytes. System state is much larger han that. It contains everything not just what the developer decided to allow you to save.

My BG3 saves are massive. Not at the PC but very much in the Gigabytes

Nintendo did it on the wii

I was afraid I was too old and people wouldn't even know games used to do this.

So isn't this like what stadia wanted to do with its integration with YouTube where you could watch someone's letsplay and there'd be a button that could take you to where they were so you can experience it or see if you can do better?

How were they able to patent it if something like this was already described by another company years ago?

So... they're inventing level codes you can re-enter to start from there.

I'm massively impressed by Sony, clearly revolutionary technology right there.

Sounds cool and all but I heavily doubt they would do the work to implement it like that. Replay value doesn't add market value in the view of the producers. So there is not much money to be made from the large amount of work this requires.

Of course if they ever do it, feel free to correct me, people from the future