unreal-actor-editing

name	unreal-actor-editing
description	Manage actors in UE levels via UCP. Use when the user asks to spawn, delete, move, duplicate, select, or otherwise manipulate actors in the Unreal Engine editor.

Unreal Actor Editing

Manage actors in Unreal Engine levels through UCP's call command. This skill guides you to use engine-provided actor subsystems and libraries.

Prerequisite: The unreal-client-protocol skill must be available and the UE editor must be running with the UCP plugin enabled.

Engine Built-in Actor Libraries

UEditorActorSubsystem

CDO Path: /Script/UnrealEd.Default__EditorActorSubsystem

This is the primary API for actor manipulation in the editor:

Function	Description
GetAllLevelActors()	Get all actors in the current level
GetAllLevelActorsOfClass(ActorClass)	Get all actors of a specific class
GetSelectedLevelActors()	Get currently selected actors
SetSelectedLevelActors(ActorsToSelect)	Set actor selection
SelectNothing()	Deselect all actors
SpawnActorFromClass(ActorClass, Location, Rotation)	Spawn a new actor
SpawnActorFromObject(ObjectToUse, Location, Rotation)	Spawn from an existing asset
DuplicateActor(ActorToDuplicate, ToWorld, Offset)	Duplicate an actor
DuplicateActors(ActorsToDuplicate, ToWorld, Offset)	Duplicate multiple actors
DestroyActor(ActorToDestroy)	Delete an actor
DestroyActors(ActorsToDestroy)	Delete multiple actors
SetActorTransform(Actor, WorldTransform)	Set actor transform
ConvertActors(Actors, ActorClass)	Convert actors to a different class

Examples

Get all actors in level:

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"GetAllLevelActors"}

Get all static mesh actors:

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"GetAllLevelActorsOfClass","params":{"ActorClass":"/Script/Engine.StaticMeshActor"}}

Spawn a point light:

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"SpawnActorFromClass","params":{"ActorClass":"/Script/Engine.PointLight","Location":{"X":0,"Y":0,"Z":200}}}

Destroy an actor:

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"DestroyActor","params":{"ActorToDestroy":"/Game/Maps/Main.Main:PersistentLevel.PointLight_0"}}

UGameplayStatics

CDO Path: /Script/Engine.Default__GameplayStatics

Useful for runtime/game queries:

Function	Description
GetAllActorsOfClass(WorldContextObject, ActorClass)	Find actors by class
GetAllActorsWithTag(WorldContextObject, Tag)	Find actors by tag
GetAllActorsOfClassWithTag(WorldContextObject, ActorClass, Tag)	Combined class + tag filter
GetAllActorsWithInterface(WorldContextObject, Interface)	Find actors implementing an interface
GetActorOfClass(WorldContextObject, ActorClass)	Get first actor of class
FindNearestActor(WorldContextObject, Origin, ActorClass)	Find nearest actor of class to a location
GetActorArrayAverageLocation(Actors)	Get average location of an array of actors
GetActorArrayBounds(Actors, bOnlyCollidingComponents)	Get combined bounds of an array of actors
GetPlayerPawn(WorldContextObject, PlayerIndex)	Get player pawn
GetPlayerController(WorldContextObject, PlayerIndex)	Get player controller
GetPlayerCameraManager(WorldContextObject, PlayerIndex)	Get camera manager

UEditorLevelLibrary

CDO Path: /Script/EditorScriptingUtilities.Default__EditorLevelLibrary

Unique level editing functions not covered by UEditorActorSubsystem:

Function	Description
JoinStaticMeshActors(ActorsToJoin, JoinOptions)	Merge static meshes into one
ReplaceSelectedActors(InAssetPath)	Replace selected actors with given asset
GetPIEWorlds()	Get worlds from Play-In-Editor sessions

Layer Management (ULayersSubsystem)

Get the instance via FindObjectInstances with ClassName set to /Script/UnrealEd.LayersSubsystem.

Function	Description
CreateLayer(LayerName)	Create a new layer
DeleteLayer(LayerToDelete)	Delete a layer
RenameLayer(OriginalLayerName, NewLayerName)	Rename a layer
AddActorToLayer(Actor, LayerName)	Add a single actor to a layer
RemoveActorFromLayer(Actor, LayerName)	Remove a single actor from a layer
AddActorsToLayer(Actors, LayerName)	Add multiple actors to a layer
GetActorsFromLayer(LayerName)	Get all actors in a layer
SetLayerVisibility(LayerName, bIsVisible)	Show/hide a layer
SelectActorsInLayer(LayerName)	Select all actors in a layer
AddAllLayerNamesTo(OutLayers)	Get all layer names

Examples

Find the LayersSubsystem instance:

{"object":"/Script/UnrealClientProtocol.Default__ObjectOperationLibrary","function":"FindObjectInstances","params":{"ClassName":"/Script/UnrealEd.LayersSubsystem"}}

Create a layer (use the instance path returned above):

{"object":"<layers_subsystem_instance_path>","function":"CreateLayer","params":{"LayerName":"Lighting"}}

Add an actor to a layer:

{"object":"<layers_subsystem_instance_path>","function":"AddActorToLayer","params":{"Actor":"/Game/Maps/Main.Main:PersistentLevel.PointLight_0","LayerName":"Lighting"}}

Actor Grouping (UActorGroupingUtils)

Get the CDO at /Script/UnrealEd.Default__ActorGroupingUtils, then call Get() on it to obtain the singleton instance.

Function	Description
GroupActors(Actors)	Group specified actors
UngroupActors(Actors)	Ungroup specified actors
GroupSelected()	Group currently selected actors
UngroupSelected()	Ungroup currently selected actors
LockSelectedGroups()	Lock selected groups
UnlockSelectedGroups()	Unlock selected groups
CanGroupActors()	Check if current selection can be grouped

Examples

Get the grouping utils instance:

{"object":"/Script/UnrealEd.Default__ActorGroupingUtils","function":"Get"}

Group selected actors (use the instance returned by Get):

{"object":"<actor_grouping_utils_instance_path>","function":"GroupSelected"}

Actor Folders (on Actor instances)

Functions called directly on actor instance paths:

Function	Description
GetFolderPath()	Get the actor's folder path in the outliner
SetFolderPath(NewFolderPath)	Set the actor's folder path in the outliner

Examples

Get an actor's folder:

{"object":"/Game/Maps/Main.Main:PersistentLevel.PointLight_0","function":"GetFolderPath"}

Move an actor into a folder:

{"object":"/Game/Maps/Main.Main:PersistentLevel.PointLight_0","function":"SetFolderPath","params":{"NewFolderPath":"Lighting/Dynamic"}}

Actor Attachment (on Actor instances)

Functions called directly on actor instance paths:

Function	Description
K2_AttachToActor(ParentActor, SocketName, LocationRule, RotationRule, ScaleRule, bWeldSimulatedBodies)	Attach this actor to a parent actor
K2_DetachFromActor(LocationRule, RotationRule, ScaleRule)	Detach this actor from its parent

Rules are EAttachmentRule values: KeepRelative, KeepWorld, SnapToTarget.

Examples

Attach an actor to another:

{"object":"/Game/Maps/Main.Main:PersistentLevel.Cube_0","function":"K2_AttachToActor","params":{"ParentActor":"/Game/Maps/Main.Main:PersistentLevel.Sphere_0","SocketName":"None","LocationRule":"KeepWorld","RotationRule":"KeepWorld","ScaleRule":"KeepWorld","bWeldSimulatedBodies":false}}

Detach an actor:

{"object":"/Game/Maps/Main.Main:PersistentLevel.Cube_0","function":"K2_DetachFromActor","params":{"LocationRule":"KeepWorld","RotationRule":"KeepWorld","ScaleRule":"KeepWorld"}}

Level Management (ULevelEditorSubsystem + UEditorLevelUtils)

ULevelEditorSubsystem

Get the instance via FindObjectInstances with ClassName set to /Script/LevelEditor.LevelEditorSubsystem.

Function	Description
NewLevel(AssetPath)	Create a new level
NewLevelFromTemplate(AssetPath, TemplatePath)	Create a new level from template
LoadLevel(AssetPath)	Load a level
SaveCurrentLevel()	Save the current level
SaveAllDirtyLevels()	Save all modified levels
SetCurrentLevelByName(LevelName)	Switch current level
GetCurrentLevel()	Get the current level
PilotLevelActor(ActorToPilot)	Pilot an actor in the viewport
EjectPilotLevelActor()	Stop piloting an actor

Examples

Find the LevelEditorSubsystem instance:

{"object":"/Script/UnrealClientProtocol.Default__ObjectOperationLibrary","function":"FindObjectInstances","params":{"ClassName":"/Script/LevelEditor.LevelEditorSubsystem"}}

Save the current level:

{"object":"<level_editor_subsystem_instance_path>","function":"SaveCurrentLevel"}

UEditorLevelUtils

CDO Path: /Script/UnrealEd.Default__EditorLevelUtils

Function	Description
CreateNewStreamingLevel(LevelStreamingClass, NewLevelPath, bMoveSelectedActors)	Create a new streaming level
MoveActorsToLevel(ActorsToMove, DestLevel, bWarnAboutReferences, bWarnAboutRenaming)	Move actors to another level
K2_AddLevelToWorld(World, LevelPath, LevelStreamingClass)	Add a sub-level to the world
K2_RemoveLevelFromWorld(Level)	Remove a sub-level from the world
SetLevelVisibility(Level, bShouldBeVisible, bForceLayersVisible)	Show/hide a level
GetLevels(World)	Get all levels in a world

Viewport & Camera (UUnrealEditorSubsystem)

Get the instance via FindObjectInstances with ClassName set to /Script/UnrealEd.UnrealEditorSubsystem.

Function	Description
GetLevelViewportCameraInfo(OutCameraLocation, OutCameraRotation)	Get the viewport camera position and rotation
SetLevelViewportCameraInfo(CameraLocation, CameraRotation)	Set the viewport camera position and rotation
GetEditorWorld()	Get the current editor world
ScreenToWorld(ScreenPosition)	Convert screen coordinates to world coordinates
WorldToScreen(WorldPosition)	Convert world coordinates to screen coordinates

Also available via UEditorUtilityLibrary:

CDO Path: /Script/Blutility.Default__EditorUtilityLibrary

Function	Description
GetSelectionBounds(Origin, BoxExtent, SphereRadius)	Get bounding info of the current selection

Examples

Find the UnrealEditorSubsystem instance:

{"object":"/Script/UnrealClientProtocol.Default__ObjectOperationLibrary","function":"FindObjectInstances","params":{"ClassName":"/Script/UnrealEd.UnrealEditorSubsystem"}}

Get viewport camera info:

{"object":"<unreal_editor_subsystem_instance_path>","function":"GetLevelViewportCameraInfo"}

Set viewport camera position:

{"object":"<unreal_editor_subsystem_instance_path>","function":"SetLevelViewportCameraInfo","params":{"CameraLocation":{"X":0,"Y":0,"Z":500},"CameraRotation":{"Pitch":-45,"Yaw":0,"Roll":0}}}

Get selection bounds:

{"object":"/Script/Blutility.Default__EditorUtilityLibrary","function":"GetSelectionBounds"}

Common Patterns

Discover and inspect actors

First get all actors, then inspect a specific actor (run as separate calls):

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"GetAllLevelActors"}

{"object":"/Script/UnrealClientProtocol.Default__ObjectOperationLibrary","function":"GetObjectProperty","params":{"ObjectPath":"<actor_path>","PropertyName":"RelativeLocation"}}

Move an actor

Use the unreal-object-operation skill to set properties on the actor's root component:

{"object":"/Script/UnrealClientProtocol.Default__ObjectOperationLibrary","function":"SetObjectProperty","params":{"ObjectPath":"<actor_root_component_path>","PropertyName":"RelativeLocation","JsonValue":"{\"X\":100,\"Y\":200,\"Z\":0}"}}

Spawn, position, and select

Spawn an actor, then get selection (run as separate calls):

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"SpawnActorFromClass","params":{"ActorClass":"/Script/Engine.PointLight","Location":{"X":0,"Y":0,"Z":300}}}

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"GetSelectedLevelActors"}

Organize actors into folders

{"object":"/Script/UnrealEd.Default__EditorActorSubsystem","function":"GetAllLevelActorsOfClass","params":{"ActorClass":"/Script/Engine.PointLight"}}

Then set folder paths on each returned actor:

{"object":"/Game/Maps/Main.Main:PersistentLevel.PointLight_0","function":"SetFolderPath","params":{"NewFolderPath":"Lighting"}}

Attach actors together

{"object":"/Game/Maps/Main.Main:PersistentLevel.ChildActor_0","function":"K2_AttachToActor","params":{"ParentActor":"/Game/Maps/Main.Main:PersistentLevel.ParentActor_0","SocketName":"None","LocationRule":"KeepWorld","RotationRule":"KeepWorld","ScaleRule":"KeepWorld","bWeldSimulatedBodies":false}}