I am working on a game with a lot of interactable objects and I would like to be able to save the current game progress and to be able to loaded it later. So this kind of game save is very much like RTS games, where nearly the status of all game objects have to be saved in order to resume the game. Is it possible to achieve such kind of game save in Unreal?
Yes Possible. How you Organize it and what Data you want to track is Up to you. The save and Load Process is pretty straight forward.
https://docs.unrealengine.com/latest/INT/Gameplay/SaveGame/Blueprints/index.html
I know how to save some key attributes to save game but I have problem saving and loading a very large number of them. Technically I might have to retrieve all the actors from the level and save them.
Ok fine let me Kickstart your thinking =)
First Create a Interface I called mine ISavable.
Next every Blueprint that you want to save Data has to implement that Interface.
Next add the OnSave event to your BP (if it does not appear close and reopen the BP)
The Implementation is Individual for each different BP since they have different Data to save. In my case I added all the important Data to a Array of Units (custom Struct)
Last step is to tell everyone that has that Interface to save. Every BP in that case knows how to save “itself” and where. But that Event anywhere you want as long as you can Call it easily.
Its a very basic System and it gets the Job done. There are more advanced techniques but this one is pretty straight forward and easy to use. If you got Child Classes and want to save differently simply add the OnSave event again you can also call the parent Save functionality by right clicking the event.
Now go ahead and make a great RTS =)