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# System prepended metadata

title: ERWIN - Physics

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# ERWIN - Physics

### Current state: Non-deterministic Physics with Unity Physx

* \+ No gameplay/code changes necessary
* \+ Complete physics interaction possible for replays
* \- Buggy af (even with enhanced determinism enabled)

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### Deterministic Physics with Unity Physics

* \+ No gameplay changes necessary
* \+ Complete physics interaction possible for replays
* \+ Probably the future: Cool, new and fast
* \- Either pre-release 0.51 version with Unity LTS (>2020.3.30f1, e.g., 2021.3.11f1 LTS)
* \- Or experimental 1.0 release with Unity Beta (>2022.2.0b8, latest is 2022.2.0b11)
* \- Many new concepts to learn (Entity System)
* \- Large API changes / bugs possible
* \- May not actually be the solution

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### "Fake"-Deterministic Physics
Note: No physics interaction for replays (record transform instead of input)
- \+ Probably very stable
- \+ Same framework can be used to animate rewind of Erwin and environment
- \+ More consistent with setting (past can't be changed)
- ~ Replay could still be "disturbed" through collision detection, if wanted
- \- Large gameplay changes necessary (entire concept changes)
- \- No physics interaction possible (or only fake-interaction)


### Other alternatives

TODO