Sublevel

A child level streamed in/out of a persistent level. Used for open-world streaming and modular maps.

Level

A scene containing actors, lighting, geometry. Open a level via Open Level. Sublevels stream in/out.

OpenLevel — load a new level by name

bAbsolute=true reloads from scratch. LevelName is the map asset name without path.

GetCurrentLevelName — get name of the current level

OpenLevel — load a level by name

UGameplayStatics::OpenLevel. Use OpenLevelBySoftObjectPtr for asset references.

GetCurrentLevelName — get the name of the currently loaded level

GetSubsystem — get a subsystem instance (GameInstance, World, etc.)

Pure node. For GameInstance subsystems: GetGameInstance → GetSubsystem. For World subsystems: GetWorld → GetSubsystem. Subsystems are auto-instanced singletons — great for organizing game systems.

Level transition with loading screen

Pattern: CreateWidget(WBP_LoadingScreen) → AddToViewport(ZOrder=100) → LoadStreamLevel or OpenLevel(NewMapName). For async: AsyncLoadLevel → OnCompleted → RemoveFromParent(LoadingWidget). Store persistent data in GameInstance before transition. Use Seamless Travel for multiplayer.

Level transition: save data then open new level

Pattern: custom trigger or UI button → [save player data to SaveSlot] → OpenLevel(LevelName='Level_02', bAbsolute=true, Options=''). For loading screen: SetGlobalTimeDilation(0.001) briefly while level loads (freeze world), or use AsyncLoadLevel with progress callback. Key: OpenLevel is in GameplayStatics. 'LevelName' is the map asset name (not full path). bAbsolute=true discards current level completely. Options string can pass params like '?GameMode=BP_GM'.

Less (float) — A < B