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  3. ULevelInstanceSubsystem

ULevelInstanceSubsystem

[ULevelInstanceSubsystem](API\Runtime\Engine\ULevelInstanceSubsystem)

API > API/Runtime > API/Runtime/Engine

ULevelInstanceSubsystem

   
Name ULevelInstanceSubsystem
Type class
Header File /Engine/Source/Runtime/Engine/Public/LevelInstance/LevelInstanceSubsystem.h
Include Path #include "LevelInstance/LevelInstanceSubsystem.h"

Syntax

UCLASS (MinimalAPI)  
class ULevelInstanceSubsystem :  
    public UWorldSubsystem ,  
    public IStreamingWorldSubsystemInterface

Inheritance Hierarchy

Implements Interfaces

Constructors

Name Remarks Include Path Unreal Specifiers

ULevelInstanceSubsystem()

   LevelInstance/LevelInstanceSubsystem.h  

Destructors

Name Remarks Include Path Unreal Specifiers

virtual ~ULevelInstanceSubsystem()

   LevelInstance/LevelInstanceSubsystem.h  

Classes

Name Remarks
FLevelInstanceChanged Editor-only event triggered when level instance is committed with changes
FLevelInstanceEdit  
FLevelInstanceEditCancelled  
FLevelInstancesUpdated Editor-only event triggered when level instances are reloaded after a change
FPropertyOverrideEdit  

Structs

Name Remarks
FLevelInstance  
FLevelsToRemoveScope  

Constants

Name Type Remarks Include Path
bPrimitiveColorHandlerRegistered bool   LevelInstance/LevelInstanceSubsystem.h

Variables

Protected

Name Type Remarks Include Path Unreal Specifiers
bIsCommittingLevelInstance bool   LevelInstance/LevelInstanceSubsystem.h  
bIsCreatingLevelInstance bool   LevelInstance/LevelInstanceSubsystem.h  
ChildEdits TMap< FLevelInstanceID, int32 >   LevelInstance/LevelInstanceSubsystem.h  
CurrentEditLevelInstanceActor FWorldPartitionReference   LevelInstance/LevelInstanceSubsystem.h  
LevelInstanceChangedEvent FLevelInstanceChanged   LevelInstance/LevelInstanceSubsystem.h  
LevelInstanceEdit TUniquePtr< FLevelInstanceEdit >   LevelInstance/LevelInstanceSubsystem.h  
LevelInstanceEditCancelled FLevelInstanceEditCancelled   LevelInstance/LevelInstanceSubsystem.h  
LevelInstancesToLoadOrUpdate TMap< ILevelInstanceInterface *, bool >   LevelInstance/LevelInstanceSubsystem.h  
LevelInstancesToUnload TSet< FLevelInstanceID >   LevelInstance/LevelInstanceSubsystem.h  
LevelInstancesUpdatedEvent FLevelInstancesUpdated   LevelInstance/LevelInstanceSubsystem.h  
LevelsToRemoveScope TUniquePtr< FLevelsToRemoveScope > Optional scope to accelerate level unload by batching them. LevelInstance/LevelInstanceSubsystem.h  
LoadedLevelInstances TMap< FLevelInstanceID, FLevelInstance >   LevelInstance/LevelInstanceSubsystem.h  
LoadingLevelInstances TSet< FLevelInstanceID >   LevelInstance/LevelInstanceSubsystem.h  
PropertyOverrideEdit TUniquePtr< FPropertyOverrideEdit >   LevelInstance/LevelInstanceSubsystem.h  
RegisteredLevelInstances TMap< FLevelInstanceID, ILevelInstanceInterface * >   LevelInstance/LevelInstanceSubsystem.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

void BlockLoadLevelInstance ( ILevelInstanceInterface* LevelInstance
)

   LevelInstance/LevelInstanceSubsystem.h  

void BlockUnloadLevelInstance ( ILevelInstanceInterface* LevelInstance
)

   LevelInstance/LevelInstanceSubsystem.h  

bool BreakLevelInstance ( ILevelInstanceInterface* LevelInstance,
uint32 Levels,
TArray< AActor* >* OutMovedActors,
ELevelInstanceBreakFlags Flags
)

   LevelInstance/LevelInstanceSubsystem.h  

bool CanBreakLevelInstance ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool CanCommitLevelInstance ( const ILevelInstanceInterface* LevelInstance,
bool bDiscardEdits,
FText* OutReason
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool CanCreateLevelInstanceFrom ( const TArray< AActor* >& ActorsToMove,
FText* OutReason
)

   LevelInstance/LevelInstanceSubsystem.h  

bool CanEditLevelInstance ( const ILevelInstanceInterface* LevelInstance,
FText* OutReason
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool CanMoveActorToLevel ( const AActor* Actor,
FText* OutReason
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool CanPackAllLoadedActors()

   LevelInstance/LevelInstanceSubsystem.h  

bool CommitLevelInstance ( ILevelInstanceInterface* LevelInstance,
bool bDiscardEdits,
TSet< FName >* DirtyPackages
)

   LevelInstance/LevelInstanceSubsystem.h  

ILevelInstanceInterface * CreateLevelInstanceFrom ( const TArray< AActor* >& ActorsToMove,
const FNewLevelInstanceParams& CreationParams
)

   LevelInstance/LevelInstanceSubsystem.h  

void EditLevelInstance ( ILevelInstanceInterface* LevelInstance,
TWeakObjectPtr< AActor > ContextActorPtr
)

   LevelInstance/LevelInstanceSubsystem.h  

void ForEachActorInLevelInstance ( const ILevelInstanceInterface* LevelInstance,
TFunctionRef< bool(AActor*LevelActor)> Operation
) const

   LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceActorAncestors ( const ULevel* Level,
TFunctionRef< bool(AActor*)> Operation
) const

 Returns the upper chain of level instance actors for the specified level starting with the level instance referencing the level. LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceAncestors ( AActor* Actor,
TFunctionRef< bool(ILevelInstanceInterface*)> Operation
) const

   LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceAncestors ( const AActor* Actor,
TFunctionRef< bool(const ILevelInstanceInterface*)> Operation
) const

   LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceAncestorsAndSelf ( const AActor* Actor,
TFunctionRef< bool(const ILevelInstanceInterface*)> Operation
) const

 Runs a lambda operation along the ancestors that own the LevelInstance. LevelInstance/LevelInstanceSubsystem.h  
  LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceChild ( const ILevelInstanceInterface* LevelInstance,
bool bRecursive,
TFunctionRef< bool(const ILevelInstanceInterface*)> Operation
) const

   LevelInstance/LevelInstanceSubsystem.h  

void ForEachLevelInstanceChild ( ILevelInstanceInterface* LevelInstance,
bool bRecursive,
TFunctionRef< bool(ILevelInstanceInterface*)> Operation
) const

   LevelInstance/LevelInstanceSubsystem.h  

ILevelInstanceInterface * GetEditingLevelInstance()

   LevelInstance/LevelInstanceSubsystem.h  

ILevelInstanceInterface * GetLevelInstance ( const FLevelInstanceID& LevelInstanceID
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool GetLevelInstanceBounds ( const ILevelInstanceInterface* LevelInstance,
FBox& OutBounds
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool GetLevelInstanceEditorBounds ( const ILevelInstanceInterface* LevelInstance,
FBox& OutBounds
) const

   LevelInstance/LevelInstanceSubsystem.h  

ULevel * GetLevelInstanceLevel ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

ULevelStreamingLevelInstance * GetLevelInstanceLevelStreaming ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

TArray< ILevelInstanceInterface * > GetLevelInstances ( const FString& WorldAssetPackage
) const

   LevelInstance/LevelInstanceSubsystem.h  

ILevelInstanceInterface * GetOwningLevelInstance ( const ULevel* Level
) const

   LevelInstance/LevelInstanceSubsystem.h  

ILevelInstanceInterface * GetParentLevelInstance ( const AActor* Actor
) const

   LevelInstance/LevelInstanceSubsystem.h  

TArray< AActor * > GetParentLevelInstanceActors ( const ULevel* Level
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool HasChildEdit ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool HasDirtyChildrenLevelInstances ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool HasParentEdit ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsCurrent ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsEditingLevelInstance ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsEditingLevelInstanceDirty ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsEditingLevelInstancePropertyOverrides ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsLoaded ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsLoading ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool IsSubSelectionEnabled()

   LevelInstance/LevelInstanceSubsystem.h  

bool LevelInstanceHasLevelScriptBlueprint ( const ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

bool MoveActorsTo ( ILevelInstanceInterface* LevelInstance,
const TArray< AActor* >& ActorsToMove,
TArray< AActor* >* OutActors
)

   LevelInstance/LevelInstanceSubsystem.h  

bool MoveActorsToLevel ( const TArray< AActor* >& ActorsToRemove,
ULevel* DestinationLevel,
TArray< AActor* >* OutActors
) const

   LevelInstance/LevelInstanceSubsystem.h  

void OnActorDeleted ( AActor* Actor
)

   LevelInstance/LevelInstanceSubsystem.h  

void OnExitEditorMode()

   LevelInstance/LevelInstanceSubsystem.h  

FLevelInstanceChanged & OnLevelInstanceChanged()

   LevelInstance/LevelInstanceSubsystem.h  

FLevelInstanceEditCancelled & OnLevelInstanceEditCancelled()

   LevelInstance/LevelInstanceSubsystem.h  

FLevelInstancesUpdated & OnLevelInstancesUpdated()

   LevelInstance/LevelInstanceSubsystem.h  

void OnTryExitEditorMode()

   LevelInstance/LevelInstanceSubsystem.h  

void PackAllLoadedActors()

   LevelInstance/LevelInstanceSubsystem.h  

bool PassLevelInstanceFilter ( UWorld* World,
const FWorldPartitionHandle& Actor
) const

   LevelInstance/LevelInstanceSubsystem.h  

FString PrefixWithParentLevelInstanceActorLabels ( const FString& ActorLabel,
const ULevel* Level
) const

   LevelInstance/LevelInstanceSubsystem.h  

FLevelInstanceID RegisterLevelInstance ( ILevelInstanceInterface* LevelInstance
)

   LevelInstance/LevelInstanceSubsystem.h  

void RequestLoadLevelInstance ( ILevelInstanceInterface* LevelInstance,
bool bUpdate
)

   LevelInstance/LevelInstanceSubsystem.h  

void RequestUnloadLevelInstance ( ILevelInstanceInterface* LevelInstance
)

   LevelInstance/LevelInstanceSubsystem.h  

bool SetCurrent ( ILevelInstanceInterface* LevelInstance
) const

   LevelInstance/LevelInstanceSubsystem.h  

void SetIsHiddenEdLayer ( ILevelInstanceInterface* LevelInstance,
bool bIsHiddenEdLayer
)

   LevelInstance/LevelInstanceSubsystem.h  

void SetIsTemporarilyHiddenInEditor ( ILevelInstanceInterface* LevelInstance,
bool bIsHidden
)

   LevelInstance/LevelInstanceSubsystem.h  

void Tick()

   LevelInstance/LevelInstanceSubsystem.h  

void UnregisterLevelInstance ( ILevelInstanceInterface* LevelInstance
)

   LevelInstance/LevelInstanceSubsystem.h  

Overridden from UWorldSubsystem

Name Remarks Include Path Unreal Specifiers

virtual bool DoesSupportWorldType ( EWorldType::Type WorldType
) const

   LevelInstance/LevelInstanceSubsystem.h  

Overridden from USubsystem

Name Remarks Include Path Unreal Specifiers

virtual void Deinitialize()

 Implement this for deinitialization of instances of the system LevelInstance/LevelInstanceSubsystem.h  

virtual void Initialize ( FSubsystemCollectionBase& Collection
)

 Initializes the world subsystem. LevelInstance/LevelInstanceSubsystem.h  

Overridden from IStreamingWorldSubsystemInterface

Name Remarks Include Path Unreal Specifiers

virtual void OnUpdateStreamingState()

   LevelInstance/LevelInstanceSubsystem.h  

Static

Name Remarks Include Path Unreal Specifiers

static void AddReferencedObjects ( UObject* InThis,
FReferenceCollector& Collector
)

   LevelInstance/LevelInstanceSubsystem.h  

static bool CanUsePackage ( FName InPackageName
)

   LevelInstance/LevelInstanceSubsystem.h  

static bool CanUseWorldAsset ( const ILevelInstanceInterface* LevelInstance,
TSoftObjectPtr< UWorld > WorldAsset,
FString* OutReason
)

 Checks if a WorldAsset can/should be used in a LevelInstance LevelInstance/LevelInstanceSubsystem.h  

static bool CheckForLoop ( const ILevelInstanceInterface* LevelInstance,
TArray< TPair< FText, TSoftObjectPtr< UWorld > > >* LoopInfo,
const ILevelInstanceInterface** LoopStart
)

   LevelInstance/LevelInstanceSubsystem.h  

static bool CheckForLoop ( const ILevelInstanceInterface* LevelInstance,
TSoftObjectPtr< UWorld > WorldAsset,
TArray< TPair< FText, TSoftObjectPtr< UWorld > > >* LoopInfo,
const ILevelInstanceInterface** LoopStart
)

 Lambda expr format that checks ancestor owners of a LevelInstance. LevelInstance/LevelInstanceSubsystem.h  

static bool GetLevelInstanceBoundsFromPackage ( const FTransform& InstanceTransform,
FName LevelPackage,
FBox& OutBounds
)

   LevelInstance/LevelInstanceSubsystem.h  

static ULevel * GetOwningLevel ( const ULevel* Level,
bool bFollowChainToNonLevelInstanceOwningLevel
)

   LevelInstance/LevelInstanceSubsystem.h  

static void RegisterPrimitiveColorHandler()

   LevelInstance/LevelInstanceSubsystem.h  

static void ResetLoadersForWorldAsset ( const FString& WorldAsset
)

   LevelInstance/LevelInstanceSubsystem.h  

static bool ShouldIgnoreDirtyPackage ( UPackage* DirtyPackage,
const UWorld* EditingWorld
)

   LevelInstance/LevelInstanceSubsystem.h  

static void UnregisterPrimitiveColorHandler()

   LevelInstance/LevelInstanceSubsystem.h  

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