So, I am making metroidvania.
My character run through a level and change it (open/close doors, lit candles, pull some triggers etc.)
What is the best way to save all this changes to restore the level state after level reload?
Do I really have to somehow register all “changable” objects and it’s state in some kind of “game_session” to keep it and restore it from such object or there is a better way to store such complex state?
Load/Save steps:
An excellent discussion of loading/saving in Unity3D by Xarbrough:
And another excellent set of notes and considerations by karliss_coldwild:
Loading/Saving ScriptableObjects by a proxy identifier such as name:
When loading, you can never re-create a MonoBehaviour or ScriptableObject instance directly from JSON. Save data needs to be all entirely plain C# data with no Unity objects in it.
The reason is they are hybrid C# and native engine objects, and when the JSON package calls new to make one, it cannot make the native engine portion of the object, so you end up with a defective “dead” Unity object.
Instead you must first create the MonoBehaviour using AddComponent() on a GameObject instance, or use ScriptableObject.CreateInstance() to make your SO, then use the appropriate JSON “populate object” call to fill in its public fields.
If you want to use PlayerPrefs to save your game, it’s always better to use a JSON-based wrapper such as this one I forked from a fellow named Brett M Johnson on github:
Do not use the binary formatter/serializer: it is insecure, it cannot be made secure, and it makes debugging very difficult, plus it actually will NOT prevent people from modifying your save data on their computers.
A good summary of the problem space:
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You can have objects that need to restore their state register themselves into a registry of level state data. Then when the scene is loaded, they can pull their state out and set themselves up.
Just consider how much state you need to save. Potentially it’s not as much as you expected.
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