Sky Actor
Components, setup properties, clock handles, and refresh controls on the Agentic Atmos sky actor
Sky Actor
AAtmosSkyActor is the native output actor for Agentic Atmos on Unreal Engine 5.8. It owns the components that render the sky and applies the resolved day-cycle and weather state to them.
Use one sky actor per world. Other directional lights, sky lights, atmosphere, cloud, or fog producers can still contribute to the frame, including components inside streamed levels.
Owned components
These are component references on the actor, not alternative places to author a reusable look.
| Property | Component / role |
|---|---|
SunLight | Directional light for the sun. |
MoonLight | Directional light for the moon. |
LightningFlashLight | Directional light for lightning flashes. |
SkyLight | Ambient sky light with real-time capture. |
SkyAtmosphere | Rayleigh and Mie scattering and aerial perspective. |
HeightFog | Exponential height fog and volumetric fog medium. |
VolumetricCloud | Volumetric cloud rendering. |
WindSource | Engine directional wind source. |
PostProcessA, PostProcessB | The two sides of a day-look post-process crossfade. |
Effects | Host for weather effects. |
ShelterBuffer, ShelterBufferDistant | Near and distant precipitation shelter captures. |
SnowTrails | Painter for tracks in settled snow. |
WindFlag, SunHandle, NorthHandle | Viewport authoring handles. |
Sky-dome imagery uses pooled static-mesh shell components selected by the look's SkyDome.Shells. There is no separate public sky-dome component property to assign. Ground fog uses its own renderer and requires placement and terrain data; it is not created merely by assigning a cycle.
Basic controls
| Property | Meaning |
|---|---|
TimeOfDay | Clock handle in HHMM units, from 0 to 2400; 1730 means 17:30. Default 1200. |
bPauseClock | Pause/resume handle for the world clock. Default false. |
bOverrideDayLength | Allow this actor to own the day length rather than the calendar configuration. Default false. |
DayLengthMinutes | Real minutes per in-game day when the override is enabled. Default 30; minimum 0.1. |
bShowSkyGizmos | Show viewport handles in the editor. Default true. |
bShowSkyGizmosInGame | Also show the handles in game. Default false. |
NorthYawDeg | World orientation of true north, in degrees. Default 0. |
SetDayLengthOverride applies the day-length override from Blueprint. SetTimeOfDayFromGizmo takes hours, unlike the HHMM details-panel property. SetWindBaselineFromGizmo takes compass direction and speed in metres per second; SetNorthYawFromGizmo takes degrees.
The actor also exposes read-only feedback including SunElevationDisplayDeg, CloudCoverageDisplay, and FogDensityDisplay. These help distinguish the composed result from values on an asset that is not currently selected.
Setup and weather
| Property | Meaning |
|---|---|
DayCycle | The UAgenticDayCycle supplying the timeline, base look, and render profile. |
LightingProfile | UAtmosPhysicsProfile used by the physical lighting solve and author-time seeding. |
bDriveWeather | Consume simulated weather. Default true. |
OverrideWeather | Authoring pin that renders a chosen UAtmosWeatherType instead of the simulator's selection. |
OverrideWeatherSeverity | Severity of that pin, from 0 to 1; default 1. Only read while a weather pin is assigned. |
DefaultRegion | Region to use when no region volume claims the sample location. |
Atmosphere | Actor-level sky-atmosphere fallback. |
Fog | Actor-level height-fog fallback. |
bAssertWind, Wind | Whether the actor asserts an ambient wind baseline, and the baseline itself. |
PostProcess | Actor-level post-process fallback. |
The renderer registry belongs to DayCycle.RenderProfile, not to the actor or a project-wide sky-profile setting. Author reusable lighting, fog, clouds, and grade in look presets.
Advanced controls
| Property | Meaning |
|---|---|
bDriveLightsFromEphemeris | Actor-level physical-light drive option; default false. The look's light settings also carry their own drive choice. |
SunCutoffElevationDeg | How far below the horizon the sun continues to contribute; default -18. |
bPinSunPosition | Hold a geometric sun position rather than following the clock. |
PinnedSunElevationDeg, PinnedSunAzimuthDeg | Pinned elevation and compass bearing; defaults 45 and 180 degrees. |
PlanetSurfaceOffsetZ | Planet surface offset from the actor, in centimetres; default -150. |
CelestialDomeRadius | Celestial dome radius in centimetres; default 1000000. |
LightningEvaluationPeriodSeconds | Lightning evaluation cadence; default one thirtieth of a second. |
ScreenFrostMaterial | Post-process material for screen frost. |
RippleSpeedMetresPerSecond, RippleTilingMetres | Surface-ripple speed and cell size. |
ShelterExtentMetres, ShelterExtentDistantMetres | Near and distant shelter coverage controls. |
ShelterCadenceNear, ShelterCadenceDistant | Capture scheduling for the two shelter tiers. |
SnowTrailsExtentMetres, SnowTrailsFadeSeconds | Snow-trail coverage and decay time constant. |
SurfaceFXExtentMetres | Surface-effects grid coverage. |
Refresh and seed methods
| Method | Purpose |
|---|---|
RefreshNow() | Explicitly re-resolve and re-apply the current authored state. Use after changing an asset beneath a paused clock or after an external edit. Available as Refresh Now in the Details panel and to Blueprint. |
RefreshFromClock() | Re-aim and re-light from the clock's current instant, including an unplayed editor world. |
SeedLookPresetFromPhysics(Target) | Write the solved light groups into a look preset. Marks the target package dirty; save the asset afterwards. |
The actor is driven by clock-change events rather than its actor tick. A paused clock is useful for authoring, but a change to external state may require Refresh Now before judging the frame.
Project settings that live elsewhere
In Project Settings → Plugins → Agentic Atmos, UAgenticAtmosphereSettings provides DefaultCalendarConfig, DefaultRegionAdapterClass, DefaultWeatherSimClass, and BlendTransitionSeconds. Geography and calendar configuration are not per-sky-actor latitude/date fields. Surface-effects, shelter, and snow-trail render targets are also project settings.
Continue with the day-cycle asset reference, console commands, or support.