Single player RPG: Using a persistence level & save/load game object when switching between levels

[anonymous_user_73094a6c1 (anonymous_user_73094a6c)]

**Please help me contribute to this thread. **

This thread discusses the following concepts for a single player RPG:

• A dedicated, persistent level to store data that is never destroyed throughout current session of the game.
• Saving data to a save game file and loading into a persistent level later on.
• Level streaming on top of your persistent level.
• Loading and appliying customization to the players main character one time when the game loads and keeping it in the persistent level.
• Remembering inventory, equipment, gear and things you pick up.

Q: Why is a persistent level important for a single player RPG?

The persistent level is a level that never gets unloaded when you start a new game or load an existing save game. Once you load a persistent map via the “Open Level” node, you can then load or unload other streaming maps at will via the “Load Streaming Map” node. Maps you load in this manner must have been added as streaming maps to the persistent map using the “Levels” window dialog, and have had their streaming method set to “Blueprint”. Ideally, you only place objects in the persistent map that are required to be there for all maps. Otherwise, persistent maps should be empty.

Q Where do I store character customization information?
A: To a save file by creating a save game object class. This information is loaded into your persistent level and applied to a pawn character. This pawn character will stay in the persistent level and never be destroyed and won’t need to be reloaded nor have it’s customizations re-applied.

Q: Where do I store story plot flags?
A: This is the same concept. To a save file by creating a save game object class. This information is then loaded into your persistent level and loaded into your plotFlagList which can be in a blueprint in your persistent level.

Q: Where do I store a list of acquired items the player has found?
A. Read the answers up above, it’s the same as any other data. Save the info to your save game file. When the player loads a game, the data is then read and stored into a blueprint in your persistent

Q: Where do I store a list of all NPCs whose location can change constantly from level to level?
A: Hmm, this is tricky. You can’t store every NPC in the entire game in your persistent level. When level streaming, you’ll load a new map into your persistent level, during this time you can decide what NPC’s need to be loaded into that area, if the loading time is long you can switch to a loading screen. Let’s say NCP’s travel from city to city, you’ll have to go through an array that keeps track of their locations to see if they needed to be loaded into the level you’re loading.

SCROLL DOWN FOR VIDEOS THAT DISCUSS Persistence, Save Game Objects when switching between levels for single player RPG

[anonymous_user_73094a6c1 (anonymous_user_73094a6c)]

Remembering variable data between levels.

UE4 - Using Game Instances & Persistent Variables

HTF do I? Save Variables between Maps ( UE4 )

HTF do I? Save Variables between Maps ( UE4 )

So far my conclusion is to use a combination of gameInstance and a custom Save Game object class to ensure persistence across map levels.

Here is another helpful video, probably the most important one:

Unreal Concepts - Persistent or Saveable Objects ( UE4 )

[anonymous_user_73094a6c1 (anonymous_user_73094a6c)]

Saving a game to a custom SaveGame object
https://docs.unrealengine.com/latest…ame/index.html

Here’s a good explanation on GameInstance vs GameState I found on this forum:
https://forums.unrealengine.com/deve…266#post672266

*GameInstance

The GameInstance Class will be created when the Game starts and will be deleted when it closes. It will SURVIVE level swaps, so you
can use it to save overall things, like a PlayerName, to keep that between Levels. You can also use it to have a State of the COMPLETE
game. Like “IsInMainMenu” or “IsInPlayMap” or “TrysToHostGame” etc.

While it makes sense to save some stuff in the GameInstance to keep it between level changes, it’s not really recommended to do that with
all kinds of stuff that you want to save. It makes more sense to use the GameSave Class to actually save parts of the game before switch the Level.

GameState

The GameState Class is unique for each Level. So if you change the Level, the GameState will be destroyed and a new one will be created for the
new loaded level. So you CAN’T save stuff in it for LevelChanges.

The GameState Class is meant to keep the State of the current Game. Or better, of the current Level.
Keep in mind that the Engine is highly affected by UnrealTournament. You will find that a lot of classes make total sense for Games like that, but
are useless for your own Game.

But in general, you would have states in that Class that manage how far the current round is. “Are we still playing?”, “Did someone win the round?”,
“What Players are connected?” (PlayerArray for example) or “Do we need to restart the round?” and all of that stuff.*

[anonymous_user_73094a6c1 (anonymous_user_73094a6c)]

When switching levels how do you keep the pawn character persistent so you don’t have to re-apply character customization?

I found it, I hope this helps anyone:

https://forums.unrealengine.com/deve…697#post833697

*GameInstance is a good place to store any data that should persist between levels, like your character info.

You can also use level streaming: **basically you have one mostly empty map, the “persistent map” as its called, while levels with actual content are loaded and unloaded on the fly and you teleport your character between them. Your character is part of the persistent map, so it won’t get destroyed **when you switch between sub levels. Look into level streaming for more information.

Any of these approaches should work fine, however.*

[emptyT]

I found this one by UnrealGaimeDev on 6/8/18 which is prolly the best I’ve seen - Info seems to be in the ‘Top Secret’ drawer along with saving methods other than click ‘s’ button to save type crap:( .
Sorry - I’m a noob and it’s been a long day of failure - but I’m lovin it!
If anyone can point me to a tut where you can have multiple save slots each with a player entered name I will love you forever!

[TUTORIAL] PERSISTENCE in Unreal Engine 4 [Eng]

[OptimisticMonkey]

I have found this useful:

Rama Save System in Code Plugins - UE Marketplace

[emptyT]

Thank you OptimisticMonkey - that looks really good - is there detailed documentation included?