`level` kit

193 tools. Generated from the plugin source; do not edit by hand.

Guide

Everything about the world the agent is building: maps and sublevels, editor layers, World Settings, environment actors (sun, sky light, sky atmosphere, fog, clouds, reflection captures), post-process volumes and settings, splines and spline meshes, gameplay/utility volumes, lighting builds and Lightmass, navigation, and (UE 5) World Partition, data layers and level instances.

Works on UE 4.27 through 5.8 (175 tools on 4.27, 192 on 5.8). Tools marked with a minimum engine version are hidden on older engines. The kit is split over eight classes (UUeaKit_Level, UUeaKit_LevelEnvironment, UUeaKit_LevelPostProcess, UUeaKit_LevelSplines, UUeaKit_LevelVolumes, UUeaKit_LevelLighting, UUeaKit_LevelNav, UUeaKit_LevelPartition) that all expose the level. namespace.

Generic actor work (spawn, transform, properties, selection, folders, groups) lives in the actor kit; asset CRUD in asset; PIE and undo in edit.

Start here

level.get_current — name, package, dirty/untitled state, actor and sublevel counts, whether the level is partitioned, unbuilt lighting and world bounds.
level.list_environment — which of sun / sky light / sky atmosphere / fog / clouds / reflection captures already exist.
level.setup_default_environment — creates the missing ones in one call.
level.get_stats — actors by class, lights, meshes, brushes, volumes, estimated triangles.

Tools

Maps and sublevels

Tool	Purpose
`level.list_maps` / `level.list_templates`	Level assets in a folder; engine template maps.
`level.create`	New level asset (optionally from a template), optionally opened and saved.
`level.open` / `level.save`	Open a level; save the open level (`saveAs` for save-as).
`level.duplicate_map` / `level.rename_map` / `level.delete_map`	Level asset lifecycle.
`level.get_current` / `level.get_stats` / `level.get_package_info`	State, content statistics, file path and size.
`level.list_sublevels` / `level.get_sublevel`	Sublevels with class, loaded/visible/locked state, transform and actor count.
`level.add_sublevel` / `level.create_sublevel` / `level.remove_sublevel`	Add an existing level, create + add a new one, remove one.
`level.set_sublevel_visible` / `_loaded` / `_locked` / `_transform` / `_streaming_class`	Per-sublevel editing state.
`level.set_current_sublevel` / `level.get_current_sublevel`	Which level new actors spawn into.
`level.move_actors_to_sublevel` / `level.list_actors_in_sublevel`	Move actors between levels; list a level's actors.
`level.list_streaming_volumes` / `level.add_streaming_volume`	Level streaming volumes and the sublevels they drive.
`level.find_actors_by_class_in_world`	Quick class query over the whole world.
`level.get_level_blueprint` / `level.open_level_blueprint`	The persistent level's Level Blueprint.

World Settings

level.set_game_mode_override, level.set_kill_z, level.set_world_gravity, level.set_world_to_meters, level.set_time_dilation_limits, and level.get_world_settings_full (every editable AWorldSettings property with its value).

Layers

level.list_layers, level.create_layer, level.rename_layer, level.delete_layer, level.set_layer_visible, level.add_actors_to_layer, level.remove_actors_from_layer, level.get_layer_actors, level.get_actor_layers.

Environment

Tool	Purpose
`level.setup_default_environment`	Sun + sky light + sky atmosphere + fog (+ clouds) in one call; skips what exists.
`level.add_directional_light` / `add_point_light` / `add_spot_light` / `add_rect_light` / `add_sky_light`	Light actors with intensity, colour, mobility, shadows and extra `properties`.
`level.add_sky_atmosphere` / `add_volumetric_cloud` / `add_exponential_fog` / `add_atmospheric_fog`	Sky and fog actors (`add_atmospheric_fog` is the legacy deprecated actor).
`level.add_reflection_capture` / `add_planar_reflection` / `list_reflection_captures` / `recapture_reflections`	Reflections.
`level.list_lights` / `level.get_light`	Lights with intensity, colour, mobility, shadows; full component property dump.
`level.set_light` / `set_lights_many`	Any subset of a light's settings, one light or many.
`level.set_light_mobility` / `set_light_channels` / `set_light_ies` / `set_light_function`	Mobility, lighting channels, IES profile, light function material.
`level.set_sun_rotation` / `level.set_sun_from_time`	Point the sun by pitch/yaw, or by hour of day + latitude.
`level.get_sky_light` / `set_sky_light` / `recapture_sky_light`	Sky light settings and recapture.
`level.get_sky_atmosphere` / `set_sky_atmosphere`	Rayleigh/Mie scattering, ground albedo, atmosphere height, multi-scattering.
`level.get_volumetric_cloud` / `set_volumetric_cloud`	Layer altitude/height, tracing distances, cloud material.
`level.get_fog` / `set_fog`	Density, falloff, colour, start distance, volumetric fog, second fog layer.
`level.list_environment` / `level.apply_environment_preset`	Overview; day / noon / sunset / night / overcast / foggy moods.
`level.delete_environment_actors`	Delete environment actors by kind.

Post process

Every setter writes FPostProcessSettings and turns on the matching bOverride_* flag. The target is a post-process volume, a camera actor, a cine camera, or any actor whose components carry post-process settings.

Tool	Purpose
`level.add_post_process_volume`	Unbound by default, so it affects the whole level.
`level.list_post_process_volumes`	Priority, bounds mode, enabled, overridden field count.
`level.get_post_process` / `level.set_post_process`	Every field with value + overridden flag; generic setter by field name.
`level.clear_post_process_overrides` / `level.reset_post_process`	Stop overriding some/all fields; default-construct the settings.
`level.set_post_process_volume`	The volume's own settings (unbound, priority, blend radius/weight, enabled, extent).
`level.set_bloom` / `set_exposure` / `set_color_grading` / `set_ambient_occlusion` / `set_motion_blur` / `set_depth_of_field` / `set_vignette` / `set_film_grain` (5.0+) / `set_chromatic_aberration` / `set_lens_flares` / `set_white_balance`	Typed setters for the common looks.
`level.set_global_illumination` (5.0+) / `level.set_reflection_method`	Lumen / SSGI / SSR.
`level.add_post_process_material` / `remove_post_process_material` / `list_post_process_materials`	Weighted blendables.
`level.copy_post_process`	Copy the whole struct (including override flags) between targets.

Splines

level.add_spline (points, closed, local/world), list_splines, get_spline, get_spline_points, add_spline_point, remove_spline_point, set_spline_point, set_spline_points, clear_spline, set_spline_closed, set_spline_point_type, reverse_spline, get_spline_length, sample_spline (distance or 0..1 alpha), sample_spline_evenly, spline_from_actors, place_along_spline (actor class or static mesh, count or spacing, align to tangent), add_spline_mesh_segments, list_spline_meshes, clear_spline_meshes, export_spline / import_spline (JSON round trip).

Volumes

level.list_volume_kinds lists every kind level.add_volume accepts: trigger_box, trigger_sphere, trigger_capsule, blocking, kill_z, pain_causing, nav_modifier, nav_mesh_bounds, audio, physics, cull_distance, lightmass_importance, precomputed_visibility, camera_blocking, level_streaming, post_process.

Then: add_volume, list_volumes, get_volume, set_volume_extent, resize_volume_to_actors, set_trigger_collision, set_pain_volume, set_physics_volume, set_audio_volume, set_cull_distances, set_nav_modifier_area, set_volume_priority, set_blocking_volume_collision, add_nav_mesh_bounds, get_nav_bounds, delete_volumes.

Lighting

level.build_lighting (quality preview/medium/high/production, wait), build_geometry, build_all, get_build_status, get_lightmass_settings / set_lightmass_settings, set_lighting_scenario / list_lighting_scenarios, set_lightmap_resolution / set_lightmap_resolution_many / get_lightmap_stats, set_lights_mobility_many, set_directional_shadows, set_light_indirect, invalidate_lighting, list_unbuilt_lights, build_reflection_captures, set_force_no_precomputed_lighting, repair_build_data_ids.

level.build_navigation (wait), get_navigation_status, list_nav_data, get_nav_settings, set_nav_agent, set_nav_runtime_generation, set_recast_settings, add_nav_link, list_nav_links, find_path, project_point_to_nav, get_random_reachable_point, is_point_on_nav, rebuild_dirty_nav.

World Partition (UE 5)

level.is_partitioned (works on 4.27 too and returns false), list_data_layers (5.1+), create_data_layer (5.1+), set_data_layer_state, add_actors_to_data_layer, remove_actors_from_data_layer, get_actor_data_layers, set_actor_spatial, list_runtime_grids (5.4+), list_external_actors, load_region / unload_region (5.3+), list_level_instances, create_level_instance, break_level_instance, list_hlod_layers.

Recipe: a lit, playable level in three calls

level.setup_default_environment {sun:true, skyLight:true, skyAtmosphere:true, fog:true, sunPitch:-45}
level.add_post_process_volume {name:"PP_Global", unbound:true}
level.set_exposure {target:"PP_Global", method:"manual", bias:1} — without this the auto exposure of a new level makes everything look flat.

Then level.save {saveAs:"/Game/Maps/MyLevel"} (a brand new level is untitled until saved).

Recipe: sunset mood

level.apply_environment_preset {preset:"sunset", keepExisting:true}
level.set_fog {density:"0.08", volumetric:"true"}
level.set_sun_from_time {hour:18.5, latitude:40} for a precise time of day.
level.set_color_grading {target:"PP_Global", temperature:"7500", saturation:"(X=1.1,Y=1.05,Z=1,W=1)"}

Recipe: a post-process look

level.set_bloom {target:"PP_Global", intensity:"0.8", threshold:"-1"}
level.set_ambient_occlusion {target:"PP_Global", intensity:"0.6", radius:"80"}
level.set_vignette {target:"PP_Global", intensity:"0.4"}
level.get_post_process {target:"PP_Global", onlyOverridden:true} to review what you changed.
level.copy_post_process {from:"PP_Global", to:"PP_Interior"} to reuse it.

Recipe: a spline road with meshes

level.add_spline {name:"Road", points:[{x:0,y:0,z:0},{x:2000,y:0,z:0},{x:4000,y:1500,z:0}]}
level.set_spline_point_type {actor:"Road", type:"curve", index:-1}
level.add_spline_mesh_segments {actor:"Road", staticMesh:"/Game/Meshes/SM_RoadSegment", forwardAxis:"x"}
level.place_along_spline {actor:"Road", staticMesh:"/Game/Meshes/SM_Lamp", spacing:800, alignToTangent:true, offset:{x:0,y:250,z:0}}
level.sample_spline_evenly {actor:"Road", count:20} if you need the waypoints for something else.

Recipe: trigger, nav bounds and a build

level.add_volume {kind:"trigger_box", name:"TB_Door", location:{x:0,y:0,z:100}, extent:{x:200,y:200,z:150}}
level.set_trigger_collision {actor:"TB_Door", profile:"Trigger", generateOverlapEvents:"true"}
level.add_nav_mesh_bounds {extent:{x:5000,y:5000,z:1000}}
level.build_navigation {wait:true} then level.get_navigation_status.
level.find_path {start:{x:0,y:0,z:0}, end:{x:3000,y:0,z:0}} to verify the navmesh connects.

Recipe: sublevel workflow

level.save first — a persistent level must exist on disk before it can own sublevels.
level.create_sublevel {folder:"/Game/Maps", name:"L_Props", streamingClass:"blueprint"}
level.set_current_sublevel {sublevel:"L_Props"} so new actors land there.
level.move_actors_to_sublevel {actors:["SM_Crate1","SM_Crate2"], sublevel:"L_Props"}
level.add_streaming_volume {sublevels:["L_Props"], extent:{x:3000,y:3000,z:1000}}
level.set_sublevel_visible / level.set_sublevel_loaded while editing; level.list_sublevels to check the state.

Recipe: data layers (UE 5.1+, partitioned levels)

level.is_partitioned — everything else in this section returns E_NOT_SUPPORTED when false.
level.create_data_layer {name:"DL_Vegetation", folder:"/Game/DataLayers", runtime:true}
level.add_actors_to_data_layer {actors:["SM_Tree1","SM_Tree2"], dataLayer:"DL_Vegetation"}
level.set_data_layer_state {dataLayer:"DL_Vegetation", state:"activated", visible:"true"}
level.set_actor_spatial {actor:"BP_QuestGiver", spatiallyLoaded:false} for actors that must always be loaded.

Gotchas

Untitled levels. A newly created level lives in /Temp/ until saved. level.add_sublevel, level.create_sublevel and level.save (without saveAs) all need a real package on disk — save the persistent level first.
Use the level.* map tools for maps, not the asset kit. level.duplicate_map, level.rename_map and level.delete_map go through world-aware engine APIs. The generic asset tools are built on UEditorAssetLibrary, which refuses anything "of type Map/Level" outright on 4.27. When one of these does fail, the reply now carries the engine's own error text.
Volumes are brushes. Most volume kinds are BSP brush actors: changing extent rebuilds the brush (level.set_volume_extent), it is not a scale. trigger_sphere and trigger_capsule are shape components instead and use radius. level.list_volume_kinds tells you which is which.
Unbound post-process volumes. level.add_post_process_volume defaults to unbound:true, which ignores the volume's bounds and affects the whole level — that is almost always what you want for a global look. Set unbound:false for a local zone.
Override flags. Reading a post-process field always returns a value; only overridden:true means the target actually applies it. level.get_post_process with onlyOverridden:true shows what you changed.
Optional setter fields are text. level.set_light, level.set_fog, level.set_bloom and friends take strings so an empty value means "leave unchanged" ("0" and "false" are real values). Colours are separate: pass color plus useColor:true.
Unknown fields are reported, not fatal. Fields that do not exist on the running engine (filmGrain* on 4.27, depthOfField.method on 5.x, bloomConvolutionScatterDispersion on 4.27) come back in failed with a reason instead of failing the whole call.
Invalid build-data GUIDs crash the engine, not just the tool. UMapBuildDataRegistry does check(Guid.IsValid()), so a sky atmosphere, reflection capture or light component carrying a zero GUID asserts the editor the moment a build touches it — and a component spawned by script can end up that way. Every build tool in this kit (build_lighting, build_geometry, build_all, build_reflection_captures, recapture_reflections) repairs them first and reports what it fixed in repaired[]. level.repair_build_data_ids runs the same pass on its own if you want to check or fix a level before handing it to another tool.
Lighting builds are slow. level.build_lighting returns immediately unless you pass wait:true; poll level.get_build_status otherwise. It is not undoable.
Unbuilt lighting. Adding or moving a static/stationary light marks the level's lighting out of date (level.get_current reports lightingUnbuilt). Use movable lights, or level.set_force_no_precomputed_lighting {enabled:true}, to skip baking entirely.
Navigation needs bounds. There is no navmesh until a nav_mesh_bounds volume exists; level.find_path and level.project_point_to_nav return "not found" until then. maxSlope is a Recast generation setting, not an agent property — set it with level.set_recast_settings {properties:[{key:"AgentMaxSlope", value:"44"}]}.
Partition tools are 5.x only and return a clean E_NOT_SUPPORTED on a non-partitioned world rather than failing hard. level.is_partitioned works on every version.
level.load_region holds the region for the session. The loader adapter must stay alive or the cells unload again immediately, so the kit keeps it until level.unload_region releases it. level.unload_region therefore only releases regions this session loaded; it reports that clearly when a box matches nothing.
Transactions. Every Mutates tool is wrapped in an editor transaction, so edit.undo works. Builds, level.save, level.delete_map and level.set_nav_agent (which writes DefaultEngine.ini) are not undoable.
Actor references accept an actor label, an object name or a unique class name ("Sun", "DirectionalLight_1", "PointLight"), matched in that order, then by unique prefix.
New and edited level actors are dirty in memory until level.save / asset.save_all.

Tools

Legend. risk 0 = read-only, 1 = harmless editor op, 2 = modifies asset, 3 = deletes/replaces asset, 4 = project/config/build op, 5 = potentially destructive (calls above MaxAutoRisk need "_confirm": true). mutates = runs in a transaction (edit.undo reverts). requires PIE / requires world = refused without a PIE session / an open level. requires plugin = unavailable while the plugin is disabled. dryRun = honours the dryRun argument. smoke = covered by edit.self_test.

`level.add_actors_to_data_layer` (risk 2, mutates, UE 5.1+, requires world)

Assigns actors to a data layer. Not smoke-tested: needs a partitioned world.

Argument	Type	Description
`actors`	array of string	required.
`dataLayer`	string	required. Data layer short name or asset path.

Returns: changed, changedCount, failed, failedCount, message.

`level.add_actors_to_layer` (risk 2, mutates, requires world)

Adds actors to an editor layer (the layer is created when missing). Not smoke-tested: needs level actors that the self-test does not own.

Argument	Type	Description
`actors`	array of string	required.
`layer`	string	required.

Returns: changed, changedCount, failed, failedCount, message.

`level.add_atmospheric_fog` (risk 1, mutates, requires world, smoke)

Adds the legacy AtmosphericFog actor (deprecated by Epic; prefer level.add_sky_atmosphere).

Argument	Type	Description
`name`	string
`location`	{x,y,z}
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_directional_light` (risk 2, mutates, requires world, smoke)

Adds a directional light (the sun).

Argument	Type	Description
`name`	string	Default `TEXT("DirectionalLight")`.
`rotation`	{x,y,z}	Pitch/yaw/roll in degrees; a negative pitch points down. Default `FUeaVec3(-45.0, 45.0, 0.0)`.
`intensity`	number	Light intensity in lux (engine default is 10). Default `10.0`.
`color`	UeaColor
`castShadows`	boolean	Default `true`.
`atmosphereSunLight`	boolean	Drive the SkyAtmosphere sun disk with this light. Default `true`.
`mobility`	string	"static", "stationary" or "movable" (default). Default `TEXT("movable")`.
`properties`	array of UeaKeyValue	Extra property assignments applied to the light component.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_exponential_fog` (risk 2, mutates, requires world, smoke)

Adds an exponential height fog actor.

Argument	Type	Description
`name`	string	Default `TEXT("ExponentialHeightFog")`.
`location`	{x,y,z}
`density`	number	Default `0.02`.
`heightFalloff`	number	Default `0.2`.
`fogColor`	UeaColor
`startDistance`	number	Distance in cm at which the fog starts. Default `0.0`.
`volumetric`	boolean	Turn on volumetric fog. Default `false`.
`extinctionScale`	number	Volumetric fog extinction scale. Default `1.0`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_nav_link` (risk 2, mutates, requires world, smoke)

Adds a nav link proxy connecting two world points (jumps, ledges, doors).

Argument	Type	Description
`start`	{x,y,z}	required. World location of the link's left point.
`end`	{x,y,z}	required. World location of the link's right point.
`bidirectional`	boolean	Traversable in both directions (default) or only from start to end. Default `true`.
`name`	string	Default `TEXT("NavLinkProxy")`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_nav_mesh_bounds` (risk 2, mutates, requires world, smoke)

Adds a nav mesh bounds volume (navigation is only generated inside these).

Argument	Type	Description
`name`	string	Default `TEXT("NavMeshBoundsVolume")`.
`location`	{x,y,z}
`extent`	{x,y,z}	Half-size in cm. Default `FUeaVec3(2000.0, 2000.0, 500.0)`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_planar_reflection` (risk 2, mutates, requires world, smoke)

Adds a planar reflection actor (mirrors, water).

Argument	Type	Description
`name`	string	Default `TEXT("PlanarReflection")`.
`location`	{x,y,z}
`rotation`	{x,y,z}
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_point_light` (risk 2, mutates, requires world, smoke)

Adds a point light.

Argument	Type	Description
`name`	string	Default `TEXT("PointLight")`.
`location`	{x,y,z}
`intensity`	number	Intensity in candelas/lumens depending on the unit (engine default is 5000). Default `5000.0`.
`color`	UeaColor
`attenuationRadius`	number	Attenuation radius in cm. Default `1000.0`.
`sourceRadius`	number	Source radius in cm (soft shadows). Default `0.0`.
`castShadows`	boolean	Default `true`.
`mobility`	string	"static", "stationary" or "movable" (default). Default `TEXT("movable")`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_post_process_material` (risk 2, mutates, requires world)

Adds a post-process material to the target's weighted blendables. Not smoke-tested: needs a project-authored post-process material.

Argument	Type	Description
`material`	string	required. Post-process material or material instance.
`weight`	number	0..1 blend weight. Default `1.0`.

Returns: target, materials, count, message.

`level.add_post_process_volume` (risk 2, mutates, requires world, smoke)

Adds a post-process volume (unbound by default, so it affects the whole level).

Argument	Type	Description
`name`	string	Default `TEXT("PostProcessVolume")`.
`unbound`	boolean	Affect the whole level regardless of where the camera is (default true). Default `true`.
`location`	{x,y,z}
`extent`	{x,y,z}	Half-size in cm when the volume is bounded. Default `FUeaVec3(1000.0, 1000.0, 1000.0)`.
`priority`	number	Higher priority wins where volumes overlap. Default `0.0`.
`blendRadius`	number	Blend distance in cm outside the volume. Default `100.0`.
`blendWeight`	number	0..1 weight of this volume's settings. Default `1.0`.
`enabled`	boolean	Default `true`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_rect_light` (risk 2, mutates, requires world, smoke)

Adds a rect (area) light.

Argument	Type	Description
`name`	string	Default `TEXT("RectLight")`.
`location`	{x,y,z}
`rotation`	{x,y,z}
`intensity`	number	Default `5000.0`.
`color`	UeaColor
`attenuationRadius`	number	Default `1000.0`.
`sourceWidth`	number	Emitter width in cm. Default `64.0`.
`sourceHeight`	number	Emitter height in cm. Default `64.0`.
`barnDoorAngle`	number	Barn door angle in degrees (0 = no barn doors). Default `0.0`.
`castShadows`	boolean	Default `true`.
`mobility`	string	Default `TEXT("movable")`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_reflection_capture` (risk 2, mutates, requires world, smoke)

Adds a sphere or box reflection capture.

Argument	Type	Description
`shape`	string	"sphere" (default) or "box". Default `TEXT("sphere")`.
`name`	string
`location`	{x,y,z}
`radius`	number	Influence radius in cm (sphere captures). Default `3000.0`.
`extent`	{x,y,z}	Half-size in cm (box captures). Default `FUeaVec3(1000.0, 1000.0, 1000.0)`.
`brightness`	number	Default `1.0`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_sky_atmosphere` (risk 2, mutates, requires world, smoke)

Adds a SkyAtmosphere actor (physically based sky).

Argument	Type	Description
`name`	string
`location`	{x,y,z}
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_sky_light` (risk 2, mutates, requires world, smoke)

Adds a sky light.

Argument	Type	Description
`name`	string	Default `TEXT("SkyLight")`.
`realTimeCapture`	boolean	Capture the sky every frame (5.x real-time capture; ignored on 4.27 where it is off by default). Default `true`.
`cubemap`	string	Cubemap texture to use instead of capturing the scene.
`intensity`	number	Default `1.0`.
`lowerHemisphereColor`	UeaColor
`mobility`	string	Default `TEXT("movable")`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_spline` (risk 2, mutates, requires world, smoke)

Creates an actor whose root is a spline component, optionally with the given points.

Argument	Type	Description
`name`	string	Default `TEXT("Spline")`.
`location`	{x,y,z}	Actor location.
`points`	array of {x,y,z}	Initial points; empty gives the engine's default two-point spline.
`closed`	boolean	Default `false`.
`space`	string	"local" (default) or "world" - how `points` are interpreted. Default `TEXT("local")`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_spline_mesh_segments` (risk 2, mutates, requires world)

Builds a spline-mesh component per segment of a spline (roads, cables, pipes). Not smoke-tested: needs a static mesh asset, which an empty project may not have.

Argument	Type	Description
`staticMesh`	string	required. Static mesh deformed along each segment.
`segments`	integer	How many segments to build; 0 (default) = one per point pair. Default `0`.
`forwardAxis`	string	"x" (default), "y" or "z". Default `TEXT("x")`.
`material`	string	Optional material override.

Returns: actor, meshes, count, message.

`level.add_spline_point` (risk 2, mutates, requires world, smoke)

Adds a point to a spline (index -1 appends).

Argument	Type	Description
`position`	{x,y,z}	required.
`space`	string	"local" (default) or "world". Default `TEXT("local")`.
`index`	integer	Insert index; -1 appends. Default `-1`.

Returns: actor, component, points, pointCount, length, closed, message.

`level.add_spot_light` (risk 2, mutates, requires world, smoke)

Adds a spot light.

Argument	Type	Description
`name`	string	Default `TEXT("SpotLight")`.
`location`	{x,y,z}
`rotation`	{x,y,z}	Pitch/yaw/roll in degrees. Default `FUeaVec3(-90.0, 0.0, 0.0)`.
`intensity`	number	Default `5000.0`.
`color`	UeaColor
`attenuationRadius`	number	Default `1000.0`.
`sourceRadius`	number	Default `0.0`.
`innerCone`	number	Inner cone half-angle in degrees. Default `0.0`.
`outerCone`	number	Outer cone half-angle in degrees. Default `44.0`.
`castShadows`	boolean	Default `true`.
`mobility`	string	Default `TEXT("movable")`.
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_streaming_volume` (risk 2, mutates, requires world)

Adds a level streaming volume that loads/shows the given sublevels. Not smoke-tested: needs existing sublevels, which the transient self-test world has none of.

Argument	Type	Description
`sublevels`	array of string	required. Sublevels the volume controls.
`name`	string
`location`	{x,y,z}
`extent`	{x,y,z}	Half-size in cm (default 1000 on each axis). Default `FUeaVec3(1000.0, 1000.0, 1000.0)`.
`usage`	string	"loading_and_visibility" (default), "loading", "visibility_blocking_on_load", "blocking_on_load". Default `TEXT("loading_and_visibility")`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_sublevel` (risk 2, mutates, requires world)

Adds an existing level asset to the current world as a streaming sublevel. Not smoke-tested: the self-test world is an unsaved transient level, which cannot own sublevels.

Argument	Type	Description
`map`	string	required. Level asset to add as a sublevel.
`streamingClass`	string	"always_loaded" (default) or "blueprint". Default `TEXT("always_loaded")`.
`location`	{x,y,z}
`rotation`	{x,y,z}

Returns: sublevel, message.

`level.add_volume` (risk 2, mutates, requires world, smoke)

Adds a volume of the given kind, sized by extent (or radius for sphere/capsule triggers).

Argument	Type	Description
`kind`	string	required. One of level.list_volume_kinds, e.g. "trigger_box", "audio", "nav_mesh_bounds".
`name`	string
`location`	{x,y,z}
`extent`	{x,y,z}	Half-size in cm (default 100 on each axis). Default `FUeaVec3(100.0, 100.0, 100.0)`.
`radius`	number	Radius in cm for trigger_sphere / trigger_capsule. Default `100.0`.
`rotation`	{x,y,z}
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.add_volumetric_cloud` (risk 2, mutates, requires world, smoke)

Adds a VolumetricCloud actor.

Argument	Type	Description
`name`	string
`location`	{x,y,z}
`properties`	array of UeaKeyValue

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.apply_environment_preset` (risk 2, mutates, requires world, smoke)

Applies a lighting mood preset (day, noon, sunset, night, overcast, foggy).

Argument	Type	Description
`preset`	string	required. day, noon, sunset, night, overcast or foggy.
`keepExisting`	boolean	Do not create missing actors, only tune the ones that exist. Default `true`.

Returns: created, existing, createdCount, message.

`level.break_level_instance` (risk 3, mutates, destructive, UE 5.1+, requires world)

Breaks a level instance apart, moving its actors back into the current level. Not smoke-tested: needs an existing level instance actor.

Argument	Type	Description
`actor`	string	required. Level instance actor to break apart.
`levels`	integer	How many nesting levels to break (1 by default). Default `1`.

Returns: instances, count, message.

`level.build_all` (risk 4, requires world)

Runs the full "Build All" (geometry, lighting, navigation, HLOD). Not smoke-tested: long running and not undoable.

Argument	Type	Description
`quality`	string	"preview" (default), "medium", "high" or "production". Default `TEXT("preview")`.
`wait`	boolean	Block until the build finishes (the tool runs off the game thread and polls). Default `false`.
`maxFrames`	integer	Maximum editor frames to wait for when `wait` is on. Default `20000`.

Returns: type, started, running, finished, framesWaited, unbuiltObjects, repaired, repairedCount, message.

`level.build_geometry` (risk 4, requires world)

Rebuilds BSP geometry of the current level. Not smoke-tested: a geometry rebuild is not undoable and would disturb the volumes created by the run.

No arguments.

Returns: type, started, running, finished, framesWaited, unbuiltObjects, repaired, repairedCount, message.

`level.build_lighting` (risk 4, requires world)

Starts a lighting build; with wait=true the tool runs off the game thread and polls until it finishes. Not smoke-tested: a lighting build takes minutes and blocks the editor.

Argument	Type	Description
`quality`	string	"preview" (default), "medium", "high" or "production". Default `TEXT("preview")`.
`wait`	boolean	Block until the build finishes (the tool runs off the game thread and polls). Default `false`.
`maxFrames`	integer	Maximum editor frames to wait for when `wait` is on. Default `20000`.

Returns: type, started, running, finished, framesWaited, unbuiltObjects, repaired, repairedCount, message.

`level.build_navigation` (risk 4, requires world)

Rebuilds the navigation data; with wait=true the tool runs off the game thread and polls. Not smoke-tested: a navigation build takes a long time and is not undoable.

Argument	Type	Description
`wait`	boolean	Block until the navigation build finishes (the tool runs off the game thread and polls). Default `false`.
`maxFrames`	integer	Maximum editor frames to wait for when `wait` is on. Default `10000`.

Returns: started, building, finished, framesWaited, remainingTasks, message.

`level.build_reflection_captures` (risk 1, requires world, smoke)

Rebuilds every reflection capture in the level (fast compared with a lighting build).

No arguments.

Returns: type, started, running, finished, framesWaited, unbuiltObjects, repaired, repairedCount, message.

`level.clear_post_process_overrides` (risk 2, mutates, requires world, smoke)

Stops overriding the named fields (empty = every field).

Argument	Type	Description
`keys`	array of string	Field names to stop overriding; empty clears every override.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.clear_spline` (risk 3, mutates, destructive, requires world, smoke)

Removes every point of a spline.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, component, points, pointCount, length, closed, message.

`level.clear_spline_meshes` (risk 3, mutates, destructive, requires world, smoke)

Removes every spline-mesh component from a spline actor.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, meshes, count, message.

`level.copy_post_process` (risk 2, mutates, requires world, smoke)

Copies the whole FPostProcessSettings struct (including override flags) from one target to another.

Argument	Type	Description
`from`	string	required. Source target.
`to`	string	required. Destination target.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.create` (risk 2, mutates, smoke)

Creates a level asset (optionally from a template), optionally opening and saving it.

Argument	Type	Description
`folder`	string	required. Destination content folder, e.g. "/Game/Maps".
`name`	string	required. Asset name of the new level.
`template`	string	Optional template level to copy (package path or unique name); empty = empty level.
`open`	boolean	Open the new level in the editor after creating it. Default `false`.
`save`	boolean	Save the new level package to disk. Default `false`.

Returns: name, package, path, opened, saved, message.

`level.create_data_layer` (risk 2, mutates, UE 5.1+, requires world)

Creates a data layer asset and registers an instance of it in the world. Not smoke-tested: needs a partitioned world, which the self-test project does not have.

Argument	Type	Description
`name`	string	required. Data layer asset name.
`folder`	string	Content folder for the data layer asset, e.g. "/Game/DataLayers". Default `TEXT("/Game/DataLayers")`.
`runtime`	boolean	Runtime data layers can be loaded/unloaded at runtime; editor-only ones cannot. Default `false`.

Returns: dataLayers, count, message.

`level.create_layer` (risk 2, mutates, requires world, smoke)

Creates an empty editor layer.

Argument	Type	Description
`name`	string	required.

Returns: layers, count.

`level.create_level_instance` (risk 2, mutates, UE 5.1+, requires world)

Moves actors into a new level asset and replaces them with a level instance actor. Not smoke-tested: writes a level asset to disk and may open a modal dialog.

Argument	Type	Description
`actors`	array of string	required. Actors to move into the new level instance.
`folder`	string	required. Destination folder for the new level asset.
`name`	string	required. Asset name of the new level.
`packed`	boolean	Create a packed level actor instead of a plain level instance. Default `false`.

Returns: instances, count, message.

`level.create_sublevel` (risk 2, mutates, requires world)

Creates a new empty level asset and adds it to the current world as a sublevel. Not smoke-tested: the self-test world is an unsaved transient level, which cannot own sublevels.

Argument	Type	Description
`folder`	string	required. Destination folder for the new level asset.
`name`	string	required. Asset name of the new level.
`streamingClass`	string	"always_loaded" (default) or "blueprint". Default `TEXT("always_loaded")`.

Returns: sublevel, message.

`level.delete_environment_actors` (risk 3, mutates, destructive, requires world, smoke)

Deletes environment actors of the given kinds (empty = all of them).

Argument	Type	Description
`kinds`	array of string	Kinds to delete: sun, sky_light, sky_atmosphere, fog, clouds, reflection_capture, planar_reflection. Empty = every environment actor.

Returns: changed, changedCount, failed, failedCount, message.

`level.delete_layer` (risk 3, mutates, destructive, requires world, smoke)

Deletes an editor layer (its actors stay in the level).

Argument	Type	Description
`name`	string	required.

Returns: layers, count.

`level.delete_map` (risk 3, mutates, destructive, smoke)

Deletes a level asset. The level must not be the one currently open.

Argument	Type	Description
`map`	string	required. Level asset (package path or unique name).

Returns: message, count.

`level.delete_volumes` (risk 3, mutates, destructive, requires world, smoke)

Deletes volumes by kind or by actor list.

Argument	Type	Description
`kind`	string	Delete every volume of this kind; ignored when `actors` is given.
`actors`	array of string	Specific volume actors to delete.

Returns: changed, changedCount, failed, failedCount, message.

`level.duplicate_map` (risk 2, mutates, smoke)

Duplicates a level asset into another folder/name.

Argument	Type	Description
`map`	string	required. Source level asset.
`folder`	string	required. Destination folder.
`name`	string	required. Destination asset name.

Returns: name, package, path, opened, saved, message.

`level.export_spline` (risk 0, requires world, smoke)

Exports a spline as JSON (points, tangents, types, closed flag).

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, json, pointCount.

`level.find_actors_by_class_in_world` (risk 0, requires world, smoke)

Actors of a class (or subclass) in the current world.

Argument	Type	Description
`class`	string	required. Class name, class path or Blueprint asset.
`includeSublevels`	boolean	Include actors living in loaded sublevels (default true). Default `true`.
`limit`	integer	Default `200`.

Returns: actors, count, total.

`level.find_path` (risk 0, requires world, smoke)

Finds a navmesh path between two world points and returns its waypoints.

Argument	Type	Description
`start`	{x,y,z}	required.
`end`	{x,y,z}	required.

Returns: valid, partial, points, count, length, message.

`level.get_actor_data_layers` (risk 0, UE 5.1+, requires world)

Data layers an actor belongs to. Not smoke-tested: needs a partitioned world and a level actor.

Argument	Type	Description
`actor`	string	required. Actor label, object name or unique class name.

Returns: dataLayers, count, message.

`level.get_actor_layers` (risk 0, requires world)

Editor layers an actor belongs to. Not smoke-tested: needs a level actor that the self-test does not own.

Argument	Type	Description
`actor`	string	required. Actor label, object name or unique class name.

Returns: layers, count.

`level.get_build_status` (risk 0, requires world, smoke)

Whether a lighting, geometry or navigation build is running, and how much is unbuilt.

No arguments.

Returns: lightingBuilding, anyBuildRunning, navigationBuilding, unbuiltLightingObjects, unbuiltReflectionCaptures, remainingNavBuildTasks, configuredLightingQuality, message.

`level.get_current` (risk 0, requires world, smoke)

The level currently open: name, package, dirty/untitled state, actor and sublevel counts, partitioning, unbuilt lighting and bounds.

No arguments.

Returns: name, package, path, dirty, untitled, actorCount, sublevelCount, partitioned, unbuiltLightingObjects, lightingUnbuilt, boundsMin, boundsMax, gameModeOverride.

`level.get_current_sublevel` (risk 0, requires world, smoke)

The level new actors are currently spawned into.

No arguments.

Returns: sublevel, message.

`level.get_fog` (risk 0, requires world, smoke)

Settings of the exponential height fog actor.

Argument	Type	Description
`actor`	string	Actor label/name; empty = the first actor of the matching kind in the level.

Returns: entries, count, message.

`level.get_layer_actors` (risk 0, requires world, smoke)

Actors assigned to an editor layer.

Argument	Type	Description
`layer`	string	required.

Returns: actors, count, total.

`level.get_level_blueprint` (risk 0, requires world, smoke)

Path and graph names of the persistent level's Level Blueprint.

No arguments.

Returns: path, name, graphs, nodeCount, message.

`level.get_light` (risk 0, requires world, smoke)

Full summary of one light, including every editable property of its light component.

Argument	Type	Description
`actor`	string	required. Actor label, object name or unique class name.

Returns: light, properties, applied, failed, message.

`level.get_lightmap_stats` (risk 0, requires world, smoke)

Lightmap resolution and lightmap UV channel of every static mesh component in the level.

No arguments.

Returns: entries, count, lightmapTotalSizeKB, shadowmapTotalSizeKB, message.

`level.get_lightmass_settings` (risk 0, requires world, smoke)

Lightmass settings of the current level.

No arguments.

Returns: entries, count, message.

`level.get_nav_bounds` (risk 0, requires world, smoke)

Nav mesh bounds volumes in the level and their combined world bounds.

No arguments.

Returns: volumes, count, min, max, hasBounds.

`level.get_nav_settings` (risk 0, smoke)

Project navigation settings: supported agents and generation options.

No arguments.

Returns: agents, count, autoCreateNavigationData, allowClientSideNavigation, buildNavigationAtRuntime, entries, message.

`level.get_navigation_status` (risk 0, requires world, smoke)

Whether navigation is building, how many tasks remain, and which agents and nav data exist.

No arguments.

Returns: navigationSystemPresent, building, locked, remainingTasks, navDataCount, navBoundsVolumes, agents, message.

`level.get_package_info` (risk 0, smoke)

File path, size on disk, dirty state and (5.x) external actor count of a level package.

Argument	Type	Description
`map`	string	Level asset; empty = the level currently open.

Returns: package, filePath, sizeBytes, dirty, exists, externalActorCount.

`level.get_post_process` (risk 0, requires world, smoke)

Reads post-process settings from a volume, camera or cine camera.

Argument	Type	Description
`onlyOverridden`	boolean	Only report the fields whose bOverride_ flag is on. Default `true`.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.get_random_reachable_point` (risk 0, requires world, smoke)

A random navigable point within a radius of an origin.

Argument	Type	Description
`origin`	{x,y,z}	required.
`radius`	number	required. Search radius in cm.

Returns: found, point, distance, message.

`level.get_sky_atmosphere` (risk 0, requires world, smoke)

Settings of the SkyAtmosphere actor.

Argument	Type	Description
`actor`	string	Actor label/name; empty = the first actor of the matching kind in the level.

Returns: entries, count, message.

`level.get_sky_light` (risk 0, requires world, smoke)

Settings of the sky light.

Argument	Type	Description
`actor`	string	Actor label/name; empty = the first actor of the matching kind in the level.

Returns: entries, count, message.

`level.get_spline` (risk 0, requires world, smoke)

One spline in detail: every point with tangents, rotation, scale and type, plus length.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, component, points, pointCount, length, closed, message.

`level.get_spline_length` (risk 0, requires world, smoke)

Total length of a spline in cm.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, samples, count, length.

`level.get_spline_points` (risk 0, requires world, smoke)

Just the points of a spline.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, component, points, pointCount, length, closed, message.

`level.get_stats` (risk 0, requires world, smoke)

Content statistics of the level currently open: actors by class, lights, meshes, brushes, volumes and an estimated triangle count.

No arguments.

Returns: actorCount, lightCount, staticMeshCount, skeletalMeshCount, brushCount, volumeCount, componentCount, estimatedTriangles, byClass, distinctClasses.

`level.get_sublevel` (risk 0, requires world)

One sublevel in detail. Not smoke-tested: the transient self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required. Sublevel name or package path (substring match on the package is accepted).

Returns: sublevel, message.

`level.get_volume` (risk 0, requires world, smoke)

One volume in detail, with every editable property of the actor.

Argument	Type	Description
`actor`	string	required. Volume actor label, name or unique class.

Returns: volume, properties, applied, failed, message.

`level.get_volumetric_cloud` (risk 0, requires world, smoke)

Settings of the VolumetricCloud actor.

Argument	Type	Description
`actor`	string	Actor label/name; empty = the first actor of the matching kind in the level.

Returns: entries, count, message.

`level.get_world_settings_full` (risk 0, requires world, smoke)

Every editable property of AWorldSettings with its current value.

No arguments.

Returns: entries, count, message.

`level.import_spline` (risk 2, mutates, requires world)

Replaces a spline's points from JSON produced by level.export_spline. Not smoke-tested: its payload is a JSON document, which cannot be written in a UHT Smoke string (single quotes there are rewritten to double quotes, so nested JSON cannot be expressed).

Argument	Type	Description
`json`	string	required. JSON produced by level.export_spline.

Returns: actor, component, points, pointCount, length, closed, message.

`level.invalidate_lighting` (risk 4, destructive, requires world)

Invalidates the baked lighting of every actor, marking the level as needing a rebuild. Not smoke-tested: throws away the project's baked lighting and is not undoable.

No arguments.

Returns: type, started, running, finished, framesWaited, unbuiltObjects, repaired, repairedCount, message.

`level.is_partitioned` (risk 0, requires world, smoke)

Whether the current world uses World Partition (always false on UE 4.27).

No arguments.

Returns: partitioned, streamingEnabled, world, externalActorCount, message.

`level.is_point_on_nav` (risk 0, requires world, smoke)

Whether a world point lies on the navmesh.

Argument	Type	Description
`point`	{x,y,z}	required.
`extent`	{x,y,z}	Search box half-size in cm around the point. Default `FUeaVec3(100.0, 100.0, 200.0)`.

Returns: found, point, distance, message.

`level.list_actors_in_sublevel` (risk 0, requires world, smoke)

Actors that live in one level (empty sublevel = the persistent level).

Argument	Type	Description
`sublevel`	string	Sublevel name or package; empty = the persistent level.
`classFilter`	string	Only actors of this class (or a subclass).
`limit`	integer	Default `200`.

Returns: actors, count, total.

`level.list_data_layers` (risk 0, UE 5.1+, requires world)

Data layer instances of the current partitioned world. Not smoke-tested: the self-test world is not partitioned, so this returns E_NOT_SUPPORTED.

No arguments.

Returns: dataLayers, count, message.

`level.list_environment` (risk 0, requires world, smoke)

Which environment actors exist in the level (sun, sky light, atmosphere, fog, clouds, captures) and their key values.

No arguments.

Returns: environment, count, message.

`level.list_external_actors` (risk 0, UE 5.0+, requires world, smoke)

External actor packages of the current world (one package per actor in a partitioned level).

Argument	Type	Description
`limit`	integer	Default `200`.

Returns: packages, count, total, message.

`level.list_hlod_layers` (risk 0, UE 5.0+, smoke)

HLOD layer assets available in the project.

No arguments.

Returns: layers, count, message.

`level.list_layers` (risk 0, requires world, smoke)

Editor layers of the current world with visibility and actor counts.

No arguments.

Returns: layers, count.

`level.list_level_instances` (risk 0, UE 5.1+, requires world, smoke)

Level instance actors in the current world.

No arguments.

Returns: instances, count, message.

`level.list_lighting_scenarios` (risk 0, requires world, smoke)

Levels flagged as lighting scenarios.

No arguments.

Returns: sublevels, count.

`level.list_lights` (risk 0, requires world, smoke)

Lights in the level with intensity, colour, mobility and shadow state.

Argument	Type	Description
`classFilter`	string	Light class to keep, e.g. "PointLight"; empty = every light.
`mobility`	string	"static", "stationary" or "movable"; empty = any.
`limit`	integer	Default `200`.

Returns: lights, count, total.

`level.list_maps` (risk 0, smoke)

Level (UWorld) assets in a content folder, filtered by name substring.

Argument	Type	Description
`folder`	string	Content folder to search, e.g. "/Game/Maps". Empty = "/Game".
`recursive`	boolean	Default `true`.
`nameContains`	string	Case-insensitive substring the map name must contain.
`limit`	integer	Default `200`.

Returns: maps, count, total.

`level.list_nav_data` (risk 0, requires world, smoke)

Navigation data actors in the level with their agent parameters.

No arguments.

Returns: navData, count, message.

`level.list_nav_links` (risk 0, requires world, smoke)

Nav link proxies in the level.

No arguments.

Returns: links, count, message.

`level.list_post_process_materials` (risk 0, requires world, smoke)

Post-process materials currently blended by the target.

Argument	Type	Description
`target`	string	required. Post-process volume, camera actor or any actor with post-process settings.

Returns: target, materials, count, message.

`level.list_post_process_volumes` (risk 0, requires world, smoke)

Post-process volumes in the level with priority, bounds mode and how many fields they override.

No arguments.

Returns: volumes, count.

`level.list_reflection_captures` (risk 0, requires world, smoke)

Reflection capture actors in the level.

No arguments.

Returns: actors, count, total.

`level.list_runtime_grids` (risk 0, UE 5.0+, requires world)

Runtime grids of the world's partition runtime hash. Not smoke-tested: needs a partitioned world.

No arguments.

Returns: grids, count, message.

`level.list_spline_meshes` (risk 0, requires world, smoke)

Spline-mesh components on a spline actor.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, meshes, count, message.

`level.list_splines` (risk 0, requires world, smoke)

Actors in the level that carry a spline component.

No arguments.

Returns: splines, count.

`level.list_streaming_volumes` (risk 0, requires world, smoke)

Level streaming volumes in the current world with the sublevels they drive.

No arguments.

Returns: actors, count, total.

`level.list_sublevels` (risk 0, requires world, smoke)

Streaming sublevels of the current world with class, loaded/visible/locked state, transform and actor count.

No arguments.

Returns: sublevels, count.

`level.list_templates` (risk 0, smoke)

Engine template levels that level.create can copy (/Engine/Maps/Templates).

No arguments.

Returns: maps, count, total.

`level.list_unbuilt_lights` (risk 0, requires world, smoke)

Lights that contribute to baked lighting while the level's lighting is out of date.

No arguments.

Returns: lights, count, unbuiltObjects, message.

`level.list_volume_kinds` (risk 0, smoke)

Every kind level.add_volume accepts, with its actor class and whether it is a BSP brush or a shape component.

No arguments.

Returns: kinds, count.

`level.list_volumes` (risk 0, requires world, smoke)

Volumes in the level, optionally of one kind.

Argument	Type	Description
`kind`	string	Kind to keep; empty = every volume.
`limit`	integer	Default `200`.

Returns: volumes, count.

`level.load_region` (risk 1, UE 5.3+, requires world)

Loads the partition cells intersecting a world-space box into the editor. Not smoke-tested: needs a partitioned world.

Argument	Type	Description
`min`	{x,y,z}	required. Minimum corner of the world-space box to load/unload.
`max`	{x,y,z}	required. Maximum corner of the world-space box.

Returns: applied, min, max, message.

`level.move_actors_to_sublevel` (risk 2, mutates, requires world)

Moves actors from their current level into another loaded level. Not smoke-tested: the self-test world has no sublevels to move actors into.

Argument	Type	Description
`actors`	array of string	required.
`sublevel`	string	required. Destination sublevel; empty is not accepted (use the persistent level name).

Returns: changed, changedCount, failed, failedCount, message.

`level.open` (risk 2)

Opens a level in the editor. Not smoke-tested: swapping the open level is not undoable and would disturb every other tool in the run.

Argument	Type	Description
`map`	string	required. Level asset to open (package path or unique name).
`saveCurrent`	boolean	Save dirty packages before switching. Default `false`.

Returns: name, package, path, opened, saved, message.

`level.open_level_blueprint` (risk 1, requires world)

Opens the Level Blueprint editor. Not smoke-tested: opens an editor window.

No arguments.

Returns: path, name, graphs, nodeCount, message.

`level.place_along_spline` (risk 2, mutates, requires world, smoke)

Spawns copies of an actor class or a static mesh along a spline.

Argument	Type	Description
`actorClass`	string	Actor class to spawn; ignored when `staticMesh` is given.
`staticMesh`	string	Static mesh to place (spawns AStaticMeshActor).
`count`	integer	How many copies to place; ignored when `spacing` is greater than 0. Default `5`.
`spacing`	number	Distance in cm between copies; 0 uses `count`. Default `0.0`.
`alignToTangent`	boolean	Rotate each copy to face along the spline. Default `true`.
`offset`	{x,y,z}	Extra offset in cm applied to each copy.

Returns: changed, changedCount, failed, failedCount, message.

`level.project_point_to_nav` (risk 0, requires world, smoke)

Projects a world point onto the navmesh inside a search box.

Argument	Type	Description
`point`	{x,y,z}	required.
`extent`	{x,y,z}	Search box half-size in cm around the point. Default `FUeaVec3(100.0, 100.0, 200.0)`.

Returns: found, point, distance, message.

`level.rebuild_dirty_nav` (risk 4, requires world)

Requests a rebuild of the navigation areas the editor marked dirty. Not smoke-tested: starts a navigation build that is not undoable.

No arguments.

Returns: started, building, finished, framesWaited, remainingTasks, message.

`level.recapture_reflections` (risk 1, mutates, requires world, smoke)

Rebuilds every reflection capture in the level (invalid build-data GUIDs are repaired first, since the engine asserts on them).

No arguments.

Returns: repaired, repairedCount, count, message.

`level.recapture_sky_light` (risk 1, requires world, smoke)

Recaptures the sky into the sky light's cubemap.

Argument	Type	Description
`actor`	string	Actor label/name; empty = the first actor of the matching kind in the level.

Returns: message, count.

`level.remove_actors_from_data_layer` (risk 2, mutates, UE 5.1+, requires world)

Removes actors from a data layer. Not smoke-tested: needs a partitioned world.

Argument	Type	Description
`actors`	array of string	required.
`dataLayer`	string	required. Data layer short name or asset path.

Returns: changed, changedCount, failed, failedCount, message.

`level.remove_actors_from_layer` (risk 2, mutates, requires world)

Removes actors from an editor layer. Not smoke-tested: needs level actors that the self-test does not own.

Argument	Type	Description
`actors`	array of string	required.
`layer`	string	required.

Returns: changed, changedCount, failed, failedCount, message.

`level.remove_post_process_material` (risk 2, mutates, requires world)

Removes a post-process material from the target's weighted blendables. Not smoke-tested: needs a project-authored post-process material.

Argument	Type	Description
`material`	string	required.

Returns: target, materials, count, message.

`level.remove_spline_point` (risk 3, mutates, destructive, requires world, smoke)

Removes one point from a spline.

Argument	Type	Description
`index`	integer	required.

Returns: actor, component, points, pointCount, length, closed, message.

`level.remove_sublevel` (risk 3, mutates, destructive, requires world)

Removes a sublevel from the current world (the asset is kept). Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required. Sublevel name or package path (substring match on the package is accepted).

Returns: message, count.

`level.rename_layer` (risk 2, mutates, requires world, smoke)

Renames an editor layer.

Argument	Type	Description
`name`	string	required.
`newName`	string	required.

Returns: layers, count.

`level.rename_map` (risk 3, mutates, smoke)

Renames a level asset in place (leaves a redirector).

Argument	Type	Description
`map`	string	required. Level asset to rename.
`newName`	string	required. New asset name (no path).

Returns: name, package, path, opened, saved, message.

`level.repair_build_data_ids` (risk 1, mutates, requires world, smoke)

Replaces invalid (zero) build-data GUIDs on sky atmosphere, reflection capture and light components. The engine asserts on them during a build, so every build tool in this kit runs this first.

No arguments.

Returns: repaired, repairedCount, count, message.

`level.reset_post_process` (risk 3, mutates, destructive, requires world, smoke)

Resets the target's post-process settings to the engine defaults (every override cleared).

Argument	Type	Description
`target`	string	required. Post-process volume, camera actor or any actor with post-process settings.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.resize_volume_to_actors` (risk 2, mutates, requires world)

Moves and resizes a volume so it encloses the given actors, plus a padding margin. Not smoke-tested: needs level actors that the self-test does not own.

Argument	Type	Description
`actors`	array of string	required. Actors the volume must enclose.
`padding`	number	Extra margin in cm added on every side. Default `100.0`.

Returns: volume, properties, applied, failed, message.

`level.reverse_spline` (risk 2, mutates, requires world, smoke)

Reverses the point order of a spline.

Argument	Type	Description
`actor`	string	required. Actor carrying the spline component.
`component`	string	Component name when the actor has more than one spline.

Returns: actor, component, points, pointCount, length, closed, message.

`level.sample_spline` (risk 0, requires world, smoke)

Location, rotation, tangent and up vector at a distance (or 0..1 alpha) along a spline.

Argument	Type	Description
`distance`	number	Distance along the spline in cm; ignored when `alpha` is given. Default `0.0`.
`alpha`	string	Position along the spline as 0..1; empty uses `distance`.
`space`	string	"local" or "world" (default). Default `TEXT("world")`.

Returns: actor, samples, count, length.

`level.sample_spline_evenly` (risk 0, requires world, smoke)

N evenly spaced samples along a spline.

Argument	Type	Description
`count`	integer	required. How many samples to return (>= 2).
`space`	string	"local" or "world" (default). Default `TEXT("world")`.

Returns: actor, samples, count, length.

`level.save` (risk 2)

Saves the level currently open (optionally "save as", optionally with its loaded sublevels). Not smoke-tested: writes to disk and an untitled level opens a modal Save As dialog.

Argument	Type	Description
`saveAs`	string	Optional package path for "save as", e.g. "/Game/Maps/Copy".
`saveSublevels`	boolean	Also save every loaded sublevel. Default `false`.

Returns: name, package, path, opened, saved, message.

`level.set_actor_spatial` (risk 2, mutates, UE 5.0+, requires world)

Whether an actor streams with the partition grid, and which runtime grid it belongs to. Not smoke-tested: needs a level actor that the self-test does not own.

Argument	Type	Description
`actor`	string	required.
`spatiallyLoaded`	boolean	required. Spatially loaded actors stream with the grid; non-spatial ones are always loaded.
`runtimeGrid`	string	Runtime grid name; empty leaves it unchanged.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.set_ambient_occlusion` (risk 2, mutates, requires world, smoke)

Screen-space ambient occlusion intensity, radius, static fraction, fade distance and power.

Argument	Type	Description
`intensity`	string
`radius`	string
`staticFraction`	string
`fadeDistance`	string
`power`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_audio_volume` (risk 2, mutates, requires world)

Priority, enabled flag and reverb of an audio volume. Not smoke-tested: needs an audio volume, which the smoke chain does not keep.

Argument	Type	Description
`priority`	string
`enabled`	string
`reverbEffect`	string	Reverb effect asset.
`reverbVolume`	string	Reverb volume 0..1.
`properties`	array of UeaKeyValue

Returns: volume, properties, applied, failed, message.

`level.set_blocking_volume_collision` (risk 2, mutates, requires world)

Collision profile of a blocking volume. Not smoke-tested: needs a blocking volume, which the smoke chain does not keep.

Argument	Type	Description
`profile`	string	required. Collision profile name, e.g. "BlockAll", "InvisibleWall".

Returns: volume, properties, applied, failed, message.

`level.set_bloom` (risk 2, mutates, requires world, smoke)

Bloom method, intensity, threshold and size.

Argument	Type	Description
`method`	string	"standard" (gaussian) or "convolution".
`intensity`	string
`threshold`	string
`sizeScale`	string
`convolutionScatterDispersion`	string	5.0+ only.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_chromatic_aberration` (risk 2, mutates, requires world, smoke)

Chromatic aberration (scene fringe) intensity and start offset.

Argument	Type	Description
`intensity`	string
`startOffset`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_color_grading` (risk 2, mutates, requires world, smoke)

Colour grading: saturation, contrast, gamma, gain, offset, white balance and scene colour tint.

Argument	Type	Description
`saturation`	string	FVector4 fields accept "(X=1,Y=1,Z=1,W=1)" or "1,1,1,1".
`contrast`	string
`gamma`	string
`gain`	string
`offset`	string
`temperature`	string
`tint`	string
`sceneColorTint`	string	Scene colour tint as "(R=1,G=1,B=1,A=1)".

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_cull_distances` (risk 2, mutates, requires world)

Size/distance pairs of a cull distance volume. Not smoke-tested: needs a cull distance volume, which the smoke chain does not keep.

Argument	Type	Description
`entries`	array of UeaCullDistanceEntry	required.

Returns: volume, properties, applied, failed, message.

`level.set_current_sublevel` (risk 1, requires world, smoke)

Makes a sublevel the current level new actors spawn into (empty = the persistent level).

Argument	Type	Description
`sublevel`	string	Sublevel name or package path; empty = the persistent level.

Returns: sublevel, message.

`level.set_data_layer_state` (risk 2, mutates, UE 5.1+, requires world)

Initial runtime state, editor visibility and editor loading of a data layer. Not smoke-tested: needs a partitioned world.

Argument	Type	Description
`dataLayer`	string	required. Data layer short name or asset path.
`state`	string	"loaded", "activated" or "unloaded" (the initial runtime state).
`visible`	string	Editor visibility.
`loadedInEditor`	string	Whether the layer's actors are loaded in the editor.

Returns: dataLayers, count, message.

`level.set_depth_of_field` (risk 2, mutates, requires world, smoke)

Depth of field: focal distance, f-stop, sensor width, focal region and blur sizes.

Argument	Type	Description
`focalDistance`	string
`fstop`	string
`sensorWidth`	string
`focalRegion`	string
`nearBlur`	string
`farBlur`	string
`method`	string	4.27 only (DepthOfFieldMethod); reported as failed on 5.x, where only Cinematic DoF exists.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_directional_shadows` (risk 2, mutates, requires world, smoke)

Cascaded shadow map settings of a directional light.

Argument	Type	Description
`actor`	string	Directional light; empty = the first one in the level.
`cascades`	string
`dynamicShadowDistance`	string
`distanceFieldShadows`	string
`cascadeDistribution`	string

Returns: entries, count, message.

`level.set_exposure` (risk 2, mutates, requires world, smoke)

Auto-exposure method, bias, brightness range and adaptation speed.

Argument	Type	Description
`method`	string	"manual", "histogram" or "basic".
`bias`	string
`minBrightness`	string
`maxBrightness`	string
`speedUp`	string
`speedDown`	string
`applyPhysicalCamera`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_film_grain` (risk 2, mutates, UE 5.0+, requires world, smoke)

Film grain intensity and its shadow/midtone/highlight weights.

Argument	Type	Description
`intensity`	string
`intensityShadows`	string
`intensityMidtones`	string
`intensityHighlights`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_fog` (risk 2, mutates, requires world, smoke)

Changes any subset of the exponential height fog settings.

Argument	Type	Description
`actor`	string
`density`	string
`heightFalloff`	string
`fogColor`	UeaColor
`useFogColor`	boolean	Default `false`.
`startDistance`	string
`volumetric`	string
`extinctionScale`	string
`secondFogDensity`	string
`secondFogHeightFalloff`	string
`secondFogHeightOffset`	string
`volumetricScatteringDistribution`	string
`volumetricAlbedo`	UeaColor
`useVolumetricAlbedo`	boolean	Default `false`.
`properties`	array of UeaKeyValue

Returns: entries, count, message.

`level.set_force_no_precomputed_lighting` (risk 2, mutates, requires world, smoke)

Turns "Force No Precomputed Lighting" on or off in World Settings (fully dynamic lighting).

Argument	Type	Description
`enabled`	boolean	required.

Returns: entries, count, message.

`level.set_game_mode_override` (risk 2, mutates, requires world, smoke)

Sets (or clears) the Game Mode override of this level.

Argument	Type	Description
`gameMode`	string	Game mode class or Blueprint; empty clears the override.

Returns: entries, count, message.

`level.set_global_illumination` (risk 2, mutates, UE 5.0+, requires world, smoke)

Global illumination method (Lumen, SSGI, none) and Lumen quality.

Argument	Type	Description
`method`	string	"none", "lumen", "ssgi" or "plugin".
`lumenSceneLightingQuality`	string
`lumenFinalGatherQuality`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_kill_z` (risk 2, mutates, requires world, smoke)

Sets the Kill Z of this level (actors below it are destroyed).

Argument	Type	Description
`killZ`	number	required. Z below which actors are destroyed (cm).

Returns: entries, count, message.

`level.set_layer_visible` (risk 1, requires world, smoke)

Shows or hides every actor of an editor layer.

Argument	Type	Description
`name`	string	required.
`visible`	boolean	required.

Returns: layers, count.

`level.set_lens_flares` (risk 2, mutates, requires world, smoke)

Lens flare intensity, tint, bokeh size and threshold.

Argument	Type	Description
`intensity`	string
`tint`	string	"(R=1,G=1,B=1,A=1)".
`bokehSize`	string
`threshold`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_light` (risk 2, mutates, requires world, smoke)

Changes any subset of a light's settings (empty fields are left unchanged).

Argument	Type	Description
`actor`	string	required. Light actor label, name or unique class.
`intensity`	string
`color`	UeaColor	Colour; leave at the default and set `useColor` false to keep the current colour.
`useColor`	boolean	Apply `color` (false = keep the current colour). Default `false`.
`temperature`	string
`useTemperature`	string
`castShadows`	string
`mobility`	string	"static", "stationary" or "movable".
`attenuationRadius`	string
`innerCone`	string
`outerCone`	string
`sourceRadius`	string
`indirectIntensity`	string
`volumetricScattering`	string
`specularScale`	string
`iesTexture`	string	IES profile texture asset.
`properties`	array of UeaKeyValue

Returns: light, properties, applied, failed, message.

`level.set_light_channels` (risk 2, mutates, requires world, smoke)

Sets the lighting channels a light affects.

Argument	Type	Description
`actor`	string	required.
`channel0`	boolean	Default `true`.
`channel1`	boolean	Default `false`.
`channel2`	boolean	Default `false`.

Returns: light, properties, applied, failed, message.

`level.set_light_function` (risk 2, mutates, requires world, smoke)

Sets a light's light-function material.

Argument	Type	Description
`actor`	string	required.
`material`	string	required. Light function material; empty clears it.

Returns: light, properties, applied, failed, message.

`level.set_light_ies` (risk 2, mutates, requires world, smoke)

Sets a light's IES profile texture.

Argument	Type	Description
`actor`	string	required.
`iesTexture`	string	required. IES profile texture asset (UTextureLightProfile); empty clears it.
`useIesBrightness`	boolean	Default `false`.

Returns: light, properties, applied, failed, message.

`level.set_light_indirect` (risk 2, mutates, requires world, smoke)

Indirect lighting intensity and volumetric scattering of one light.

Argument	Type	Description
`actor`	string	required.
`indirectIntensity`	string
`volumetricScattering`	string

Returns: entries, count, message.

`level.set_light_mobility` (risk 2, mutates, requires world, smoke)

Sets a light's mobility (static, stationary or movable).

Argument	Type	Description
`actor`	string	required.
`mobility`	string	required. "static", "stationary" or "movable".

Returns: light, properties, applied, failed, message.

`level.set_lighting_scenario` (risk 2, mutates, requires world, smoke)

Marks a level as a lighting scenario (its baked lighting can be swapped at runtime).

Argument	Type	Description
`sublevel`	string	required. Sublevel name; empty = the persistent level.
`enabled`	boolean	required.

Returns: sublevels, count.

`level.set_lightmap_resolution` (risk 2, mutates, requires world)

Overrides the lightmap resolution of one mesh component. Not smoke-tested: needs a static mesh actor that the self-test does not own.

Argument	Type	Description
`actor`	string	required.
`resolution`	integer	required. Lightmap resolution in texels (power of two, e.g. 64).
`component`	string	Component name when the actor has several meshes.

Returns: entries, count, lightmapTotalSizeKB, shadowmapTotalSizeKB, message.

`level.set_lightmap_resolution_many` (risk 2, mutates, requires world, smoke)

Overrides the lightmap resolution of many actors at once.

Argument	Type	Description
`actors`	array of string	Actors to change; empty uses `classFilter`.
`classFilter`	string	Apply to every actor of this class when `actors` is empty; empty = every mesh actor.
`resolution`	integer	required.

Returns: changed, changedCount, failed, failedCount, message.

`level.set_lightmass_settings` (risk 2, mutates, requires world, smoke)

Changes any subset of the Lightmass settings of the current level.

Argument	Type	Description
`numIndirectLightingBounces`	string
`numSkyLightingBounces`	string
`indirectLightingQuality`	string
`indirectLightingSmoothness`	string
`staticLightingLevelScale`	string
`environmentColor`	string	"(R=1,G=1,B=1,A=1)".
`environmentIntensity`	string
`useAmbientOcclusion`	string
`compressLightmaps`	string
`properties`	array of UeaKeyValue	Any other LightmassSettings field by name.

Returns: entries, count, message.

`level.set_lights_many` (risk 2, mutates, requires world, smoke)

Applies the same settings to many lights at once (by list or by class).

Argument	Type	Description
`actors`	array of string	Light actors to change; empty uses `classFilter`.
`classFilter`	string	Apply to every light of this class when `actors` is empty; empty = every light.
`intensity`	string
`color`	UeaColor
`useColor`	boolean	Default `false`.
`temperature`	string
`useTemperature`	string
`castShadows`	string
`mobility`	string	"static", "stationary" or "movable".
`attenuationRadius`	string
`innerCone`	string
`outerCone`	string
`sourceRadius`	string
`indirectIntensity`	string
`volumetricScattering`	string
`specularScale`	string
`iesTexture`	string
`properties`	array of UeaKeyValue

Returns: changed, changedCount, failed, failedCount, message.

`level.set_lights_mobility_many` (risk 2, mutates, requires world, smoke)

Sets the mobility of every light (optionally of one class) at once.

Argument	Type	Description
`mobility`	string	required. "static", "stationary" or "movable".
`classFilter`	string	Light class to change; empty = every light.

Returns: changed, changedCount, failed, failedCount, message.

`level.set_motion_blur` (risk 2, mutates, requires world, smoke)

Motion blur amount, maximum, per-object size and target FPS.

Argument	Type	Description
`amount`	string
`max`	string
`perObjectSize`	string
`targetFps`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_nav_agent` (risk 4)

Changes a supported navigation agent in the project settings and writes DefaultEngine.ini. Not smoke-tested: writes the project's DefaultEngine.ini, which the self-test must not touch.

Argument	Type	Description
`name`	string	required. Agent name from level.get_nav_settings, e.g. "Default".
`radius`	string
`height`	string
`stepHeight`	string
`maxSlope`	string	Maximum walkable slope in degrees. Not an agent property: reported as unsupported and applied through level.set_recast_settings instead.

Returns: agents, count, autoCreateNavigationData, allowClientSideNavigation, buildNavigationAtRuntime, entries, message.

`level.set_nav_modifier_area` (risk 2, mutates, requires world)

Nav area class applied by a nav modifier volume. Not smoke-tested: needs a nav modifier volume, which the smoke chain does not keep.

Argument	Type	Description
`areaClass`	string	required. Nav area class, e.g. "NavArea_Null", "NavArea_Obstacle", "NavArea_Default".

Returns: volume, properties, applied, failed, message.

`level.set_nav_runtime_generation` (risk 2, mutates, requires world)

Runtime generation mode of the nav data actors (static, dynamic, dynamicModifiersOnly). Not smoke-tested: an empty project has no navigation data actor until a nav mesh bounds volume is built.

Argument	Type	Description
`mode`	string	required. "static", "dynamic" or "dynamicModifiersOnly".
`actor`	string	Nav data actor to change; empty = every nav data in the level.

Returns: navData, count, message.

`level.set_pain_volume` (risk 2, mutates, requires world)

Damage settings of a pain-causing volume. Not smoke-tested: needs a pain-causing volume, which level.add_volume can create but the smoke chain does not keep.

Argument	Type	Description
`damagePerSec`	string
`damageType`	string	Damage type class.
`painCausing`	string
`entryPain`	string

Returns: volume, properties, applied, failed, message.

`level.set_physics_volume` (risk 2, mutates, requires world)

Priority, friction, terminal velocity and water flag of a physics volume. Not smoke-tested: needs a physics volume, which the smoke chain does not keep.

Argument	Type	Description
`priority`	string
`fluidFriction`	string
`terminalVelocity`	string
`waterVolume`	string

Returns: volume, properties, applied, failed, message.

`level.set_post_process` (risk 2, mutates, requires world, smoke)

Writes arbitrary post-process fields by name (the bOverride_ flag of each is turned on).

Argument	Type	Description
`settings`	array of UeaKeyValue	required. Field name -> value; the matching bOverride_ flag is turned on automatically.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_post_process_volume` (risk 2, mutates, requires world, smoke)

Changes the volume's own settings (bounds mode, priority, blending, size).

Argument	Type	Description
`unbound`	string
`priority`	string
`blendRadius`	string
`blendWeight`	string
`enabled`	string
`extent`	{x,y,z}	New half-size in cm; rebuilds the volume's brush.
`useExtent`	boolean	Apply `extent` (false = keep the current size). Default `false`.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_recast_settings` (risk 2, mutates, requires world)

Recast navmesh generation settings (cell size, agent size, tile size, debug draw). Not smoke-tested: an empty project has no RecastNavMesh actor until navigation is built.

Argument	Type	Description
`actor`	string	RecastNavMesh actor; empty = the first one in the level.
`cellSize`	string
`cellHeight`	string
`agentRadius`	string
`agentHeight`	string
`tileSizeUU`	string	Tile size in Unreal units.
`drawDebug`	string	Draw the navmesh in the editor viewport.
`properties`	array of UeaKeyValue

Returns: entries, count, message.

`level.set_reflection_method` (risk 2, mutates, requires world, smoke)

Reflection method (Lumen, SSR, none) and screen-space reflection quality/intensity.

Argument	Type	Description
`method`	string	"none", "lumen" or "ssr" (5.0+; the SSR fields work on 4.27 too).
`ssrQuality`	string
`ssrIntensity`	string

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_sky_atmosphere` (risk 2, mutates, requires world, smoke)

Changes any subset of the SkyAtmosphere settings.

Argument	Type	Description
`actor`	string
`rayleighScatteringScale`	string
`rayleighScattering`	UeaColor
`useRayleighScattering`	boolean	Default `false`.
`mieScatteringScale`	string
`mieAnisotropy`	string
`groundAlbedo`	UeaColor
`useGroundAlbedo`	boolean	Default `false`.
`atmosphereHeight`	string	Atmosphere height in km.
`multiScattering`	string
`properties`	array of UeaKeyValue

Returns: entries, count, message.

`level.set_sky_light` (risk 2, mutates, requires world, smoke)

Changes any subset of the sky light's settings.

Argument	Type	Description
`actor`	string	Sky light actor; empty = the first one in the level.
`intensity`	string
`color`	UeaColor
`useColor`	boolean	Default `false`.
`realTimeCapture`	string
`cubemap`	string	Cubemap texture asset (switches the source to "specified cubemap").
`lowerHemisphereColor`	UeaColor
`useLowerHemisphereColor`	boolean	Default `false`.
`occlusion`	string	Occlusion (distance field ambient occlusion) intensity.
`properties`	array of UeaKeyValue

Returns: entries, count, message.

`level.set_spline_closed` (risk 2, mutates, requires world, smoke)

Opens or closes the loop of a spline.

Argument	Type	Description
`closed`	boolean	required.

Returns: actor, component, points, pointCount, length, closed, message.

`level.set_spline_point` (risk 2, mutates, requires world, smoke)

Changes any subset of one point's position, tangents, rotation, scale and type.

Argument	Type	Description
`index`	integer	required.
`position`	{x,y,z}
`usePosition`	boolean	Default `false`.
`arriveTangent`	{x,y,z}
`useArriveTangent`	boolean	Default `false`.
`leaveTangent`	{x,y,z}
`useLeaveTangent`	boolean	Default `false`.
`rotation`	{x,y,z}
`useRotation`	boolean	Default `false`.
`scale`	{x,y,z}
`useScale`	boolean	Default `false`.
`type`	string	linear, curve, constant, curveClamped or curveCustomTangent.
`space`	string	"local" (default) or "world". Default `TEXT("local")`.

Returns: actor, component, points, pointCount, length, closed, message.

`level.set_spline_point_type` (risk 2, mutates, requires world, smoke)

Sets the interpolation type of one point (index -1 = every point).

Argument	Type	Description
`type`	string	required. linear, curve, constant, curveClamped or curveCustomTangent.
`index`	integer	Point index; -1 applies to every point. Default `-1`.

Returns: actor, component, points, pointCount, length, closed, message.

`level.set_spline_points` (risk 2, mutates, requires world, smoke)

Replaces every point of a spline.

Argument	Type	Description
`points`	array of {x,y,z}	required. New point positions, replacing every existing point.
`space`	string	"local" (default) or "world". Default `TEXT("local")`.

Returns: actor, component, points, pointCount, length, closed, message.

`level.set_sublevel_loaded` (risk 2, mutates, requires world)

Loads or unloads a sublevel (flushes level streaming). Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required.
`loaded`	boolean	required.

Returns: sublevel, message.

`level.set_sublevel_locked` (risk 2, mutates, requires world)

Locks or unlocks a sublevel for editing. Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required.
`locked`	boolean	required.

Returns: sublevel, message.

`level.set_sublevel_streaming_class` (risk 2, mutates, requires world)

Switches a sublevel between always-loaded and blueprint (dynamic) streaming. Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required.
`streamingClass`	string	required. "always_loaded" or "blueprint".

Returns: sublevel, message.

`level.set_sublevel_transform` (risk 2, mutates, requires world)

Moves a sublevel by setting its editor transform. Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required.
`location`	{x,y,z}
`rotation`	{x,y,z}

Returns: sublevel, message.

`level.set_sublevel_visible` (risk 2, mutates, requires world)

Shows or hides a sublevel in the editor. Not smoke-tested: the self-test world has no sublevels.

Argument	Type	Description
`sublevel`	string	required.
`visible`	boolean	required.

Returns: sublevel, message.

`level.set_sun_from_time` (risk 2, mutates, requires world, smoke)

Points the sun using a simple solar model (hour of day + latitude).

Argument	Type	Description
`hour`	number	required. Hour of day, 0..24 (12 = noon).
`latitude`	number	Latitude in degrees (positive = northern hemisphere). Default `0.0`.
`azimuth`	number	Compass direction the sun travels through, in degrees. Default `0.0`.
`actor`	string	Directional light to rotate; empty = the first one in the level.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.set_sun_rotation` (risk 2, mutates, requires world, smoke)

Points the sun (a directional light) at a pitch/yaw.

Argument	Type	Description
`pitch`	number	required. Pitch in degrees (negative points down).
`yaw`	number	required. Yaw in degrees.
`actor`	string	Directional light to rotate; empty = the first one in the level.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.set_time_dilation_limits` (risk 2, mutates, requires world, smoke)

Sets the minimum/maximum global time dilation of this level.

Argument	Type	Description
`min`	string	Minimum global time dilation; empty leaves it unchanged.
`max`	string	Maximum global time dilation; empty leaves it unchanged.

Returns: entries, count, message.

`level.set_trigger_collision` (risk 2, mutates, requires world, smoke)

Collision profile and overlap events of a trigger volume.

Argument	Type	Description
`profile`	string	Collision profile name, e.g. "Trigger", "OverlapAllDynamic", "BlockAll".
`generateOverlapEvents`	string

Returns: volume, properties, applied, failed, message.

`level.set_vignette` (risk 2, mutates, requires world, smoke)

Vignette intensity (0..1).

Argument	Type	Description
`intensity`	string	required.

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_volume_extent` (risk 2, mutates, requires world, smoke)

Resizes a volume (rebuilds the BSP brush, or resizes the collision component of a trigger).

Argument	Type	Description
`extent`	{x,y,z}	required. New half-size in cm.
`radius`	number	New radius in cm for sphere/capsule triggers. Default `0.0`.

Returns: volume, properties, applied, failed, message.

`level.set_volume_priority` (risk 2, mutates, requires world)

Priority of an audio or post-process volume. Not smoke-tested: needs an audio or post-process volume selected by actor, covered by level.set_post_process_volume instead.

Argument	Type	Description
`priority`	number	required. Higher priority wins where volumes overlap.

Returns: volume, properties, applied, failed, message.

`level.set_volumetric_cloud` (risk 2, mutates, requires world, smoke)

Changes any subset of the VolumetricCloud settings.

Argument	Type	Description
`actor`	string
`layerBottomAltitude`	string	Cloud layer bottom altitude in km.
`layerHeight`	string	Cloud layer thickness in km.
`tracingStartMaxDistance`	string
`tracingMaxDistance`	string
`material`	string	Cloud material asset.
`properties`	array of UeaKeyValue

Returns: entries, count, message.

`level.set_white_balance` (risk 2, mutates, requires world, smoke)

White balance temperature, tint and temperature type.

Argument	Type	Description
`temperature`	string
`tint`	string
`method`	string	"whiteBalance" or "colorTemperature".

Returns: target, fields, count, overriddenCount, applied, failed, message.

`level.set_world_gravity` (risk 2, mutates, requires world, smoke)

Sets the per-level gravity override (cm/s^2 on Z).

Argument	Type	Description
`gravityZ`	number	required. Gravity on Z in cm/s^2 (engine default is -980).
`override`	boolean	required. Use this value instead of the project default.

Returns: entries, count, message.

`level.set_world_to_meters` (risk 2, mutates, requires world, smoke)

Sets WorldToMeters (Unreal units per metre, default 100).

Argument	Type	Description
`scale`	number	required. Unreal units per metre (default 100).

Returns: entries, count, message.

`level.setup_default_environment` (risk 2, mutates, requires world, smoke)

Creates the actors a lit, playable level needs (sun, sky light, sky atmosphere, fog, optionally clouds), skipping the ones that already exist.

Argument	Type	Description
`sun`	boolean	Add a directional light acting as the sun. Default `true`.
`skyLight`	boolean	Add a sky light (real-time capture on 5.x). Default `true`.
`skyAtmosphere`	boolean	Add a SkyAtmosphere actor. Default `true`.
`fog`	boolean	Add an exponential height fog actor. Default `true`.
`clouds`	boolean	Add a VolumetricCloud actor. Default `false`.
`sunPitch`	number	Sun pitch in degrees (negative points down; -45 is a mid-afternoon sun). Default `-45.0`.

Returns: created, existing, createdCount, message.

`level.spline_from_actors` (risk 2, mutates, requires world)

Creates a spline whose points are the world locations of the given actors, in order. Not smoke-tested: needs level actors that the self-test does not own.

Argument	Type	Description
`actors`	array of string	required. Actors whose locations become the spline points, in order.
`name`	string	Default `TEXT("Spline")`.
`closed`	boolean	Default `false`.

Returns: name, label, class, path, location, rotation, applied, failed, message.

`level.unload_region` (risk 1, UE 5.3+, requires world)

Unloads the partition cells intersecting a world-space box. Not smoke-tested: needs a partitioned world.

Argument	Type	Description
`min`	{x,y,z}	required. Minimum corner of the world-space box to load/unload.
`max`	{x,y,z}	required. Maximum corner of the world-space box.

Returns: applied, min, max, message.

Guide
Start here
Tools
Recipe: a lit, playable level in three calls
Recipe: sunset mood
Recipe: a post-process look
Recipe: a spline road with meshes
Recipe: trigger, nav bounds and a build
Recipe: sublevel workflow
Recipe: data layers (UE 5.1+, partitioned levels)
Gotchas
Tools

Guide​

Start here​

Tools​

Maps and sublevels​

World Settings​

Layers​

Environment​

Post process​

Splines​

Volumes​

Lighting​

Navigation​

World Partition (UE 5)​

Recipe: a lit, playable level in three calls​

Recipe: sunset mood​

Recipe: a post-process look​

Recipe: a spline road with meshes​

Recipe: trigger, nav bounds and a build​

Recipe: sublevel workflow​

Recipe: data layers (UE 5.1+, partitioned levels)​

Gotchas​

Tools​

level.add_actors_to_data_layer (risk 2, mutates, UE 5.1+, requires world)​

level.add_actors_to_layer (risk 2, mutates, requires world)​

level.add_atmospheric_fog (risk 1, mutates, requires world, smoke)​

level.add_directional_light (risk 2, mutates, requires world, smoke)​

level.add_exponential_fog (risk 2, mutates, requires world, smoke)​

level.add_nav_link (risk 2, mutates, requires world, smoke)​

level.add_nav_mesh_bounds (risk 2, mutates, requires world, smoke)​

level.add_planar_reflection (risk 2, mutates, requires world, smoke)​

level.add_point_light (risk 2, mutates, requires world, smoke)​

level.add_post_process_material (risk 2, mutates, requires world)​

level.add_post_process_volume (risk 2, mutates, requires world, smoke)​

level.add_rect_light (risk 2, mutates, requires world, smoke)​

level.add_reflection_capture (risk 2, mutates, requires world, smoke)​

level.add_sky_atmosphere (risk 2, mutates, requires world, smoke)​

level.add_sky_light (risk 2, mutates, requires world, smoke)​

level.add_spline (risk 2, mutates, requires world, smoke)​

level.add_spline_mesh_segments (risk 2, mutates, requires world)​

level.add_spline_point (risk 2, mutates, requires world, smoke)​

level.add_spot_light (risk 2, mutates, requires world, smoke)​

level.add_streaming_volume (risk 2, mutates, requires world)​

level.add_sublevel (risk 2, mutates, requires world)​

level.add_volume (risk 2, mutates, requires world, smoke)​

level.add_volumetric_cloud (risk 2, mutates, requires world, smoke)​

level.apply_environment_preset (risk 2, mutates, requires world, smoke)​

level.break_level_instance (risk 3, mutates, destructive, UE 5.1+, requires world)​

level.build_all (risk 4, requires world)​

level.build_geometry (risk 4, requires world)​

level.build_lighting (risk 4, requires world)​

level.build_navigation (risk 4, requires world)​

level.build_reflection_captures (risk 1, requires world, smoke)​

level.clear_post_process_overrides (risk 2, mutates, requires world, smoke)​

level.clear_spline (risk 3, mutates, destructive, requires world, smoke)​

level.clear_spline_meshes (risk 3, mutates, destructive, requires world, smoke)​

level.copy_post_process (risk 2, mutates, requires world, smoke)​

level.create (risk 2, mutates, smoke)​

level.create_data_layer (risk 2, mutates, UE 5.1+, requires world)​

level.create_layer (risk 2, mutates, requires world, smoke)​

level.create_level_instance (risk 2, mutates, UE 5.1+, requires world)​

level.create_sublevel (risk 2, mutates, requires world)​

level.delete_environment_actors (risk 3, mutates, destructive, requires world, smoke)​

level.delete_layer (risk 3, mutates, destructive, requires world, smoke)​

level.delete_map (risk 3, mutates, destructive, smoke)​

level.delete_volumes (risk 3, mutates, destructive, requires world, smoke)​

level.duplicate_map (risk 2, mutates, smoke)​

level.export_spline (risk 0, requires world, smoke)​

level.find_actors_by_class_in_world (risk 0, requires world, smoke)​

level.find_path (risk 0, requires world, smoke)​

level.get_actor_data_layers (risk 0, UE 5.1+, requires world)​

level.get_actor_layers (risk 0, requires world)​

level.get_build_status (risk 0, requires world, smoke)​

level.get_current (risk 0, requires world, smoke)​

level.get_current_sublevel (risk 0, requires world, smoke)​

level.get_fog (risk 0, requires world, smoke)​

level.get_layer_actors (risk 0, requires world, smoke)​

level.get_level_blueprint (risk 0, requires world, smoke)​

level.get_light (risk 0, requires world, smoke)​

level.get_lightmap_stats (risk 0, requires world, smoke)​

level.get_lightmass_settings (risk 0, requires world, smoke)​

Guide

Start here

Tools

Maps and sublevels

World Settings

Layers

Environment

Post process

Splines

Volumes

Lighting

Navigation

World Partition (UE 5)

Recipe: a lit, playable level in three calls

Recipe: sunset mood

Recipe: a post-process look

Recipe: a spline road with meshes

Recipe: trigger, nav bounds and a build

Recipe: sublevel workflow

Recipe: data layers (UE 5.1+, partitioned levels)

Gotchas

Tools

`level.add_actors_to_data_layer` (risk 2, mutates, UE 5.1+, requires world)

`level.add_actors_to_layer` (risk 2, mutates, requires world)

`level.add_atmospheric_fog` (risk 1, mutates, requires world, smoke)

`level.add_directional_light` (risk 2, mutates, requires world, smoke)

`level.add_exponential_fog` (risk 2, mutates, requires world, smoke)

`level.add_nav_link` (risk 2, mutates, requires world, smoke)

`level.add_nav_mesh_bounds` (risk 2, mutates, requires world, smoke)

`level.add_planar_reflection` (risk 2, mutates, requires world, smoke)

`level.add_point_light` (risk 2, mutates, requires world, smoke)

`level.add_post_process_material` (risk 2, mutates, requires world)

`level.add_post_process_volume` (risk 2, mutates, requires world, smoke)

`level.add_rect_light` (risk 2, mutates, requires world, smoke)

`level.add_reflection_capture` (risk 2, mutates, requires world, smoke)

`level.add_sky_atmosphere` (risk 2, mutates, requires world, smoke)

`level.add_sky_light` (risk 2, mutates, requires world, smoke)

`level.add_spline` (risk 2, mutates, requires world, smoke)

`level.add_spline_mesh_segments` (risk 2, mutates, requires world)

`level.add_spline_point` (risk 2, mutates, requires world, smoke)

`level.add_spot_light` (risk 2, mutates, requires world, smoke)

`level.add_streaming_volume` (risk 2, mutates, requires world)

`level.add_sublevel` (risk 2, mutates, requires world)

`level.add_volume` (risk 2, mutates, requires world, smoke)

`level.add_volumetric_cloud` (risk 2, mutates, requires world, smoke)

`level.apply_environment_preset` (risk 2, mutates, requires world, smoke)

`level.break_level_instance` (risk 3, mutates, destructive, UE 5.1+, requires world)

`level.build_all` (risk 4, requires world)

`level.build_geometry` (risk 4, requires world)

`level.build_lighting` (risk 4, requires world)

`level.build_navigation` (risk 4, requires world)

`level.build_reflection_captures` (risk 1, requires world, smoke)

`level.clear_post_process_overrides` (risk 2, mutates, requires world, smoke)

`level.clear_spline` (risk 3, mutates, destructive, requires world, smoke)

`level.clear_spline_meshes` (risk 3, mutates, destructive, requires world, smoke)

`level.copy_post_process` (risk 2, mutates, requires world, smoke)

`level.create` (risk 2, mutates, smoke)

`level.create_data_layer` (risk 2, mutates, UE 5.1+, requires world)

`level.create_layer` (risk 2, mutates, requires world, smoke)

`level.create_level_instance` (risk 2, mutates, UE 5.1+, requires world)

`level.create_sublevel` (risk 2, mutates, requires world)

`level.delete_environment_actors` (risk 3, mutates, destructive, requires world, smoke)

`level.delete_layer` (risk 3, mutates, destructive, requires world, smoke)

`level.delete_map` (risk 3, mutates, destructive, smoke)

`level.delete_volumes` (risk 3, mutates, destructive, requires world, smoke)

`level.duplicate_map` (risk 2, mutates, smoke)

`level.export_spline` (risk 0, requires world, smoke)

`level.find_actors_by_class_in_world` (risk 0, requires world, smoke)

`level.find_path` (risk 0, requires world, smoke)

`level.get_actor_data_layers` (risk 0, UE 5.1+, requires world)

`level.get_actor_layers` (risk 0, requires world)

`level.get_build_status` (risk 0, requires world, smoke)

`level.get_current` (risk 0, requires world, smoke)

`level.get_current_sublevel` (risk 0, requires world, smoke)

`level.get_fog` (risk 0, requires world, smoke)

`level.get_layer_actors` (risk 0, requires world, smoke)

`level.get_level_blueprint` (risk 0, requires world, smoke)

`level.get_light` (risk 0, requires world, smoke)

`level.get_lightmap_stats` (risk 0, requires world, smoke)

`level.get_lightmass_settings` (risk 0, requires world, smoke)