Sky Creator for Unreal Engine 4
Available on Marketplace
Current version: 1.23

Documentation will be updated and improved over time.

Requirements

Sky Creator requires Niagara to be enabled to display some Weather FX such as rain and snow.

Depending on your needs you also might want to enable “Support Sky Atmosphere Affecting Height Fog” in Project Settings > Rendering. If set to off (by default), the atmosphere won’t affect height fog and it will be colored by Fog Inscattering Color (black by default).

Installing the Plugin (UE4)

Open Epic Games Launcher, head to Unreal Engine > Marketplace or Library tab and find Sky Creator. Press “Install to Engine” button and choose the appropriate engine version for you.

Open your project the engine version of which have the plugin already installed and head to Plugins tab. Find the Sky Creator and set it enabled by checkbox. The engine will prompt to restart itself. Restart the editor and you will have plugin enabled and ready to work.

Installing the Plugin (UE5 EA)

Since V1.03 Sky Creator supports Unreal Engine 5 Early Access. Because of engine’s Early Access state, you can’t install plugins from Epic Launcher yet, so you’ll need to copy plugin folder to your project’s folder by hand unofficially. But make sure that you’re having latest version of the plugin installed on your version of UE4. Also be sure to have Visual Studio for Unreal Engine installed otherwise you won’t be able to compile source code.

Copy from:
“C:/Program Files/Epic Games/UE_4.27/Engine/Plugins/Marketplace/SkyCreatorPlugin” (or another directory where you have Unreal Engine installed
And paste to:
“YourProject/Plugins/SkyCreatorPlugin”.

Next time you launch your UE5 project, the engine will prompt “The SkyCreatorPlugin was designed for build 4.2X.0 Attempt to load it anyway?”, just click yes.

P.S. Please don’t expect a flawless work with early version of UE5! This support is currently unofficial.

Quickstart

After enabling the plugin go to category Lights in a Place Mode tab. Inside there you will find a new actor Sky Creator ready to be drag’n’dropped to your scene. But before adding it make sure that you deleted or at least disabled any other Directional Light, Skylight, Volumetric Cloud and Sky Atmosphere on your level.

Now Sky Creator is ready to use. Go to Details Panel and play with settings to your liking.

To create your own Weather Preset, right click in Content Browser and select
Add/Import Content > Miscellaneous > Sky Creator Weather Preset. After that select a Sky Creator actor in your scene and drag a new weather preset onto “Editor Weather Preset” variable, making a new weather preset active. Now open it and create a new weather conditions that fits to your game if you need to.

The creative power hides exactly there. Feel free to create something awesome.

To control Sky Creator’s time of day or change weather in runtime, separate controller must be used. Most of functions are already built in such as “Realtime Time of Day” or “Lerp Weather Settings” so you don’t really need to worry about it. There are an examples of a blueprint controllers in “SkyCreatorPlugin Content/Blueprints” which you can freely use in your scenes, but you can actually use whatever you want to or create a custom controller.

How to use Weather Material FX

If you want to use Sky Creator’s Weather Material FX, you need to add “MF_SC_WeatherMaterialFX” material function to your material and re-pin Base Color, Roughness and Normal connectors through it. By default, all included effects will be enabled – Wetness, Puddles and Snow. You may optionally disable some of effects using Static Bool node and plugging it into this material function.

You may also enable Occlusion and use Distant Occlusion with it by plugging “MF_SC_DistantOcclusion” material function into the Distant Occlusion pin in “MF_SC_WeatherMaterialFX” material function. See next paragraph.

How to use Occlusion

Occlusion effect is enabled by default. It uses Scene Capture Component 2D to capture a world heightmap at a certain radius around player camera once at a defined distance step to minimize performance impact. To use Occlusion effect with Weather Material FX, you need to enable this effect by plugging Static Switch node into the Use Occlusion slot of the “MF_SC_WeatherMaterialFX” material function.

If you’re using only this, you may notice that Occlusion effect is fading after reaching capture radius. To fix this you can use “SkyCreator_CaptureDistantOcclusion” blueprint. Place it in the middle of your level, adjust the width of this capture and click Capture Heightmap. After this, Distant Occlusion heightmap will be used on the materials in the area outside of radius of main Occlusion capture.

Sky Creator Actor Settings

Here’s all settings list which is meant to be set once in editor.

General

Use Editor Time of Day	Controls Time of Day by Editor. Disable if using a separate controller to drive Time of Day.
Editor Time of Day	Time of Day in Editor.
Use Editor Weather Settings	Controls Weather Settings by Editor. Disable if using a separate controller to drive Weather Settings.
Editor Weather Type	Whether to use Editor Weather Preset or Editor Weather Settings.
Editor Weather Preset	Current Weather Preset in Editor.
Editor Weather Settings	Current Weather Settings in Editor allowing to direct variable control.
Sky Creator Parameter Collection	Sky Creator Material Parameter Collection. Essential for a number of effects.
Sky Sphere Radius	Sky Sphere mesh radius in kilometers.
Show Debug Variables	Show or Hide debug variables across all sub-categories of settings.

Sky Atmosphere

Sky Atmosphere Mobility	Sky Atmosphere Mobility.
Transform Mode	– Planet Top at Absolute World Position places the top ground level of the atmosphere at the world origin coordinates (0,0,0) in the scene. The Sky Atmosphere is not movable when this option is selected. – Planet Top at Component Transform places the top ground level of the atmosphere relative to the component’s transform origin. Moving the transform of the Sky Atmosphere component, or one that it is a child of, moves the atmosphere within the level. – Planet Center at Component Transform places the atmosphere centered to the component’s transform origin. Moving the transform of the Sky Atmosphere component, or one that it is a child of, moves the atmosphere within the level.
Planet Radius	The planet radius (kilometers from the center to the ground level).
Atmosphere Height	Atmosphere Height defines the height of the atmosphere above the planet’s surface (in kilometers).
Trace Sample Count Scale	Scale the atmosphere tracing sample count. Quality level scalability. The sample count is still clamped according to scalability setting to ‘r.SkyAtmosphere.SampleCountMax’ when ‘r.SkyAtmosphere.FastSkyLUT’ is 0. The sample count is still clamped according to scalability setting to ‘r.SkyAtmosphere.FastSkyLUT.SampleCountMax’ when ‘r.SkyAtmosphere.FastSkyLUT’ is 1. The sample count is still clamped for aerial perspective according to ‘r.SkyAtmosphere.AerialPerspectiveLUT.SampleCountMaxPerSlice’.

Volumetric Clouds

Bottom Altitude	The altitude at which the cloud layer starts (kilometers above the ground).
Max Height	The altitude at which the cloud layer ends (kilometers above the ground).
Tracing Start Max Distance	The maximum distance of the volumetric surface before which we will accept to start tracing (in kilometers).
Tracing Max Distance	The maximum distance that will be traced inside the cloud layer (in kilometers).
Per Sample Atmospheric Light Transmittance	Whether to apply atmosphere transmittance per sample, instead of using the light global transmittance.
Quality
Ground Contribution	Sample the shadowed lighting contribution from the ground ontro the medium (single scattering). This adds some costs to the tracing when enabled.
Multi Scattering Approximation Octave Count	How many octave to use for the multiple-scattering approximation. This adds some costs to the tracing. 0 means single scattering only.
View Sample Count Scale	Scale the tracing sample count in primary views. Quality level scalability CVARs affect the maximum range. The sample count resolution is still clamped according to scalability setting to ‘r.VolumetricCloud.ViewRaySampleCountMax’.
Reflection Sample Count Scale	Scale the tracing sample count in reflection views. Quality level scalability CVARs affect the maximum range. The sample count resolution is still clamped according to scalability setting to ‘r.VolumetricCloud.ReflectionRaySampleMaxCount’.
Shadow View Sample Count Scale	Scale the shadow tracing sample count in primary views, only used with Advanced Output ray marched shadows. Quality level scalability CVARs affect the maximum range. The sample count resolution is still clamped according to scalability setting to ‘r.VolumetricCloud.Shadow.ViewRaySampleMaxCount’.
Shadow Reflection Sample Count Scale	Scale the shadow tracing sample count in reflection views, only used with Advanced Output ray marched shadows. Quality level scalability CVARs affect the maximum range. The sample count resolution is still clamped according to scalability setting to ‘r.VolumetricCloud.Shadow.ReflectionRaySampleMaxCount’.
Shadow Tracing Distance	The shadow tracing distance in kilometers, only used with Advanced Output ray marched shadows.
Low Cloud Map
Low Cloud Map Scale	Low Cloud Map tileable texture scale in kilometers.
Low Cloud Map Offset	Low Cloud Map tileable texture UV offset.
High Cloud Map
High Cloud Map Scale	High Cloud Map tileable texture scale in kilometers.
High Cloud Map Offset	High Cloud Map tileable texture UV offset.
High Cloud Horizon Fade Hardness	Hardness of fading High Cloud Map at horizon.
Cloud Noise
Auto Scale	Automatic Cloud 3D Noise Scaling relative to “Low Cloud Map Scale”.
Shape Noise Scale	Tileable 3D Shape Noise Scale (kilometers).
Detail Noise Scale	Tileable 3D Detail Noise Scale (kilometers).

Sky Light

Sky Light Mobility	Sky Light Mobility.
Real Time Capture	When enabled, the sky will be captured and convolved to achieve dynamic diffuse and specular environment lighting. SkyAtmosphere, VolumetricCloud Components as well as sky domes with Sky materials are taken into account. Should be enabled if using dynamic time of day.
Lower Hemisphere Is Solid Color	Whether all distant lighting from the lower hemisphere should be set to “LowerHemisphereColor. Enabling this is accurate when lighting a scene on a planet where the ground blocks the sky, however disabling it can be useful to approximate skylight bounce lighting (eg Movable light).

Sun Light

Sun Light Mobility	Sun Light Mobility.
Control Sun Direction	Whether to control Sun direction by Sky Creator.
Use Temperature	Whether to use Color temperature for sun.
Angular Diameter	Angle subtended by light source in degrees (also known as angular diameter). Defaults to 0.5357 which is the angle for our sun.
Constant Atmosphere Disk Color Scale	Whether to use constant Atmosphere Disk Color Scale for Sun.
Atmosphere Disk Color Scale	A color multiplied with the sun disk luminance.
Sun Positioning
Sun Orbit Type	Sun Orbit Type
Sunrise Time	User-defined Sunrise Time
Sunset Time	User-defined Sunset Time
Sun Dawn Offset Time	Sets “Sun Dawn Time” depending on “Sunrise Time”.
Sun Dusk Offset Time	Sets “Sun Dusk Time” depending on “Sunset Time”.
Sun Dawn Time	Sun Dawn Time.
Sun Dusk Time	Sun Dusk Time.
Sun Elevation	Sun Elevation angle in degrees.
Sun Azimuth	Sun Azimuth angle in degrees.
Sun Min Angle At Dawn & Dusk	Minimum angle of Sun below horizon at Dawn or Dusk.
Sun Fade In/Out Time	Fade in/out time for Sun at Dawn or Dusk.

Moon Light

Moon Light Mobility	Moon Light Mobility.
Control Moon Direction	Whether to control Moon direction by Sky Creator.
Use Temperature	Whether to use Color temperature for Moon.
Angular Diameter	Angle subtended by light source in degrees (also known as angular diameter). Defaults to 0.5357 which is the angle for our sun.
Constant Atmosphere Disk Color Scale	Whether to use constant Atmosphere Disk Color Scale.
Atmosphere Disk Color Scale	A color multiplied with the sun disk luminance.
Moon Phase	Moon Disk Phase.
Moon Rotation	Moon Disk Rotation.
Moon Positioning
Moon Orbit Type	Moon Orbit Type.
Moonrise Time	User-defined Moonrise Time.
Moonset Time	User-defined Moonset Time.
Moon Elevation	Moon Elevation angle in degrees.
Moon Azimuth	Moon Azimuth angle in degrees.
Moon Fade In/Out Time	Fade in/out time for Moon at Dawn or Dusk.

Exponential Height Fog

Exponential Height Fog Mobility	Exponential Height Fog Mobility.
Enable Exponential Height Fog	Whether to enable Exponential Height Fog.
Volumetric Fog	Whether to enable Volumetric fog. Scalability settings control the resolution of the fog simulation.
Fog Height Offset	Fog height offset, relative to the actor position Z.
Second Fog Height Offset	Second Fog height offset, relative to the actor position Z.

Star Map

Star Map Texture	Star Map Texture
Rotation Type	Star Map Rotation Type
Additional Rotation	Star Map Additional Rotation

Occlusion

Occlusion Capture	Whether to enable realtime Occlusion Capture.
Occlusion Render Target	Occlusion Render Target.
Occlusion Capture Width	Occlusion Capture width. Half of this value is a radius.
Occlusion Capture Height	Occlusion Capture camera height.
Occlusion Capture Realtime Update	Occlusion Capture realtime update. Expensive, so use with caution.
Occlusion Capture Step Distance	Fixed distance step to update Occlusion Capture.
Occlusion Bias	Occlusion Bias works similarly as known ‘Shadow Bias’ technique in shadow mapping. Low values can cause occlusion artifacts.
Occlusion Blur Samples	Sample count of the Occlusion Blur.
Occlusion Blur Distance	Blurring distance of the Occlusion Blur.
Occlusion Mask Fade Hardness	Hardness of fading Occlusion radial mask.

Weather FX

Precipitation General
Precipitation Spawn Radius	Precipitation spawn radius around the camera.
Enable Distant Precipitation	Whether to enable Distant Precipitation particles layer. Increases overall amount of particles so can be turned off as an optimization step.
Distant Precipitation Spawn Radius	Distant Precipitation spawn radius around the camera.
Precipitation Max View Distance	Max distance at where precipitation particles will be alive.
Precipitation Vertical Check Distance	Distance of vertical linetrace from particle spawn point to check against occlusion.
Precipitation Collision Channel	Collision Channel for precipitation particles to check against.
Precipitation Depth Fade Distance	Depth Fade distance for precipitation particles.
Precipitation Camera Fade Distance	Camera Fade distance for precipitation particles.
Precipitation Camera Fade Offset	Camera Fade Offset distance for precipitation particles.
Rain
Rain Spawn Rate Max	Max number of rain particles to spawn per second. Value is multiplied by “Rain Amount” value in weather preset.
Rain Distant Spawn Rate Max	Max number of distant rain particles to spawn per second. Value is multiplied by “Rain Amount” value in weather preset.
Rain Distance Scale Factor	Scale Factor by distance for rain particles (for better visibility).
Rain Index Of Refraction	Index of Refraction for rain particles. Set 1.0 for no refraction.
Rain Splash
Rain Splash Spawn Rate Max	Max number of rain splash particles to spawn per second. Value is multiplied by “Rain Amount” value in weather preset.
Snow
Snow Spawn Rate Max	Max number of snow particles to spawn per second. Value is multiplied by “Snow Amount” value in weather preset.
Snow Distant Spawn Rate Max	Max number of distant snow particles to spawn per second. Value is multiplied by “Snow Amount” value in weather preset.
Snow Distance Scale Factor	Scale Factor by distance for snow particles (for better visibility).
Snow Mask Hardness	Mask Hardness for snow particles. Controls how ‘soft’ they look.

Weather Material FX

Wetness
Wetness Slope Angle	Slope Angle for the Wetness effect.
Wetness Slope Smoothness	Slope Smoothness for the Wetness effect.
Puddles
Puddles Mask Scale	Scale of the Puddles Mask in world units.
Puddles Roughness	Roughness of the Puddles effect.
Puddles Slope Angle	Slope Angle for the Puddles effect.
Puddles Slope Smoothness	Slope Smoothness for the Puddles effect.
Ripples
Rain Ripples Update Rate	Update Rate of the Rain Ripples Solver. Higher values increases simulation speed.
Rain Ripples Scale	Scale of the Rain Ripples in world units.
Rain Ripples Max Density	Max density of Rain Ripples when the amount equals “1”.
Wind Ripples Scale	Scale of the Wind Ripples in world units.
Snow
Snow Mask Scale	Scale of the Snow Mask in world units.
Snow Scale	Scale of the Snow Material in world units.
Snow Roughness	Roughness of the Snow Material.
Snow Sparkles Scale	Scale of the Snow Sparkles effect in world units.
Snow Sparkles Roughness	Roughness of the Snow Sparkles effect.
Snow Slope Angle	Slope Angle for the Snow effect.
Snow Slope Smoothness	Slope Smoothness for the Snow effect.

Wind

Enable Wind	Whether to enable Wind. Affects Volumetric Clouds and Weather FX particles.
Independent Wind Control	If set to true, Cloud & Weather FX Wind is controlled by either static values or by separate controller. If set to false, Cloud & Weather FX Wind will read values from Weather Presets.
Editor Independent Wind Settings	Editor Independent Wind Settings.
Volumetric Cloud
Low Cloud Wind Direction	Wind direction for Low Cloud Layer in angles
Low Cloud Wind Speed	Wind speed for Low Cloud Layer in m/s
High Cloud Wind Direction	Wind direction for High Cloud Layer in angles
High Cloud Wind Speed	Wind speed for High Cloud Layer in m/s
Cloud Noise Wind Direction	Wind direction for Cloud Noise in angles
Cloud Noise Wind Speed Horizontal	Horizontal wind speed for Cloud Noise in m/s
Cloud Noise Wind Speed Vertical	Vertical wind speed for Cloud Noise in m/s
Cloud Wind Skew Amount	Skew clouds towards Low Cloud Wind Direction. Affected by Low Cloud Wind Speed.
Weather FX
Precipitation Wind Direction	Wind direction for Precipitation in angles
Precipitation Wind Speed	Wind speed for Precipitation

Exposure

Use Built-in Exposure Settings	Whether to use built-in Exposure Settings.
Exposure Method	Luminance computation method.
Exposure Compensation Curve	Exposure compensation based on the scene EV100. Used to calibrate the final exposure differently depending on the average scene luminance. 0: no adjustment, -1:2x darker, -2:4x darker, 1:2x brighter, 2:4x brighter, …
Exposure Metering Mask	Exposure metering mask. Bright spots on the mask will have high influence on auto-exposure metering and dark spots will have low influence.
Min Brightness	Auto-Exposure minimum adaptation. Eye Adaptation is disabled if Min = Max. Auto-exposure is implemented by choosing an exposure value for which the average luminance generates a pixel brightness equal to the Constant Calibration value. The Min/Max are expressed in pixel luminance (cd/m2).
Max Brightness	Auto-Exposure maximum adaptation. Eye Adaptation is disabled if Min = Max. Auto-exposure is implemented by choosing an exposure value for which the average luminance generates a pixel brightness equal to the Constant Calibration value. The Min/Max are expressed in pixel luminance (cd/m2).
Min EV100	Auto-Exposure minimum adaptation. Eye Adaptation is disabled if Min = Max. Auto-exposure is implemented by choosing an exposure value for which the average luminance generates a pixel brightness equal to the Constant Calibration value. The Min/Max are expressed in EV100 when using ExtendDefaultLuminanceRange (see project settings).
Max EV100	Auto-Exposure maximum adaptation. Eye Adaptation is disabled if Min = Max. Auto-exposure is implemented by choosing an exposure value for which the average luminance generates a pixel brightness equal to the Constant Calibration value. The Min/Max are expressed in EV100 when using ExtendDefaultLuminanceRange (see project settings).
Speed Up	In F-stops per second, should be >0.
Speed Down	In F-stops per second, should be >0.
Low Percent	The eye adaptation will adapt to a value extracted from the luminance histogram of the scene color. The value is defined as having x percent below this brightness. Higher values give bright spots on the screen more priority but can lead to less stable results. Lower values give the medium and darker values more priority but might cause burn out of bright spots. >0, <100, good values are in the range 70 .. 80
High Percent	The eye adaptation will adapt to a value extracted from the luminance histogram of the scene color. The value is defined as having x percent below this brightness. Higher values give bright spots on the screen more priority but can lead to less stable results. Lower values give the medium and darker values more priority but might cause burn out of bright spots. >0, <100, good values are in the range 80 .. 95
Histogram Log Min	Histogram Min value. Expressed in Log2 (Luminance).
Histogram Log Max	Histogram Max value. Expressed in Log2 (Luminance).
Histogram Min EV100	Histogram Min value. Expressed in EV100 when using ExtendDefaultLuminanceRange (see project settings).
Histogram Max EV100	Histogram Max value. Expressed in EV100 when using ExtendDefaultLuminanceRange (see project settings).

Sky Creator Weather Settings

Here’s all settings list which is meant to be used by weather presets in runtime.

Sky Atmosphere

Rayleigh
Rayleigh Scattering Scale	Rayleigh scattering coefficient scale.
Rayleigh Scattering	The Rayleigh scattering coefficients resulting from molecules in the air at an altitude of 0 kilometer.
Rayleigh Exponential Distribution	The altitude in kilometer at which Rayleigh scattering effect is reduced to 40%.
Mie
Mie Scattering Scale	Mie scattering coefficient scale.
Mie Scattering	The Mie scattering coefficients resulting from particles in the air at an altitude of 0 kilometer. As it becomes higher, light will be scattered more.
Mie Absorption Scale	Mie absorption coefficient scale.
Mie Absorption	The Mie absorption coefficients resulting from particles in the air at an altitude of 0 kilometer. As it becomes higher, light will be absorbed more.
Mie Anisotropy	A value of 0 mean light is uniformly scattered. A value closer to 1 means lights will scatter more forward, resulting in halos around light sources.
Mie Exponential Distribution	The altitude in kilometer at which Mie effects are reduced to 40%.
Absorption
Absorption Scale	Absorption coefficients for another atmosphere layer. Density increase from 0 to 1 between 10 to 25km and decreases from 1 to 0 between 25 to 40km. The default values represents ozone molecules absorption in the Earth atmosphere.
Absorption	Absorption coefficients for another atmosphere layer. Density increase from 0 to 1 between 10 to 25km and decreases from 1 to 0 between 25 to 40km. The default values represents ozone molecules absorption in the Earth atmosphere.
Art Direction
Sky Luminance Factor	Scales the luminance of pixels representing the sky, i.e. not belonging to any surface.
Height Fog Contribution	Scale the sky and atmosphere lights contribution to the height fog when SupportSkyAtmosphereAffectsHeightFog project setting is true.

Volumetric Cloud

Low Cloud Layer
Low Cloud Coverage	Coverage level of Low Cloud layer.
Low Cloud Density	Density level of Low Cloud layer.
Low Cloud Altitude	Altitude of Low Cloud layer.
Low Cloud Height	Height of Low Cloud layer.
Low Cloud Height Variation	Height Variation of Low Cloud layer.
Low Cloud Secondary Coverage	Coverage level of Low Cloud Secondary layer.
Low Cloud Secondary Altitude	Altitude of Low Cloud Secondary layer.
Low Cloud Secondary Height	Height of Low Cloud Secondary layer.
High Cloud Layer
High Cloud Coverage	Coverage level of High Cloud layer.
High Cloud Density	Density level of High Cloud layer.
High Cloud Height	Height of High Cloud layer.
High Cloud Amount Type A	Amount of ‘Type A’ clouds in High Cloud layer.
High Cloud Amount Type B	Amount of ‘Type B’ clouds in High Cloud layer.
High Cloud Amount Type C	Amount of ‘Type C’ clouds in High Cloud layer.
Cloud Lighting
Albedo	Albedo color of Volumetric Clouds.
Albedo Bottom	Albedo color of the bottom of Low Cloud layer.
Bottom Darkening	Darkening amount of the bottom of Low Cloud layer.
Night Emissive	Emissive color of Volumetric Clouds. Better to keep this value low.
Phase G	Phase function describing how much forward (G < 0) of backward (G > 0) light scatter around.
Phase G2	Second phase function describing how much forward (G < 0) of backward (G > 0) light scatter around.
Phase Blend	Lerp factor when blending the two phase functions.
Multi Scattering Contribution	Multi-scattering approximation: represents how much contribution each successive octave will add. Evaluatead per pixel.
Multi Scattering Occlusion	Multi-scattering approximation: represents how much occlussion will be reduced for each successive octave. Evaluatead per pixel.
Multi Scattering Eccentricity	Multi-scattering approximation: represents how much the phase will become isotropic for each successive octave. Evaluatead per pixel.
Cloud Noise
Shape Noise Erosion	Erosion amount of ‘Shape’ 3D Noise.
Detail Noise Erosion	Erosion amount of ‘Detail’ 3D Noise.

Sky Light

Intensity	Total energy that the light emits.
Light Color	Filter color of the light. Note that this can change the light’s effective intensity.
Lower Hemisphere Color	Lower Hemisphere Color.

Sun Light

Intensity	Maximum illumination from the light in lux.
Light Color	Filter color of the light. Note that this can change the light’s effective intensity.
Temperature	Color temperature in Kelvin of the blackbody illuminant. White (D65) is 6500K.
Volumetric Scattering Intensity	Intensity of the volumetric scattering from sun. This scales Intensity and Light Color.
Atmosphere And Cloud
Atmosphere Disk Color Scale	A color multiplied with the sun disk luminance.
Cloud Scattered Luminance Scale	Scales the lights contribution when scattered in cloud participating media.
Cloud Shadow Strength	The overall strength of the cloud shadow, higher value will block more light.
Cloud Shadow on Atmosphere Strength	The strength of the shadow on atmosphere. Disabled when 0.
Cloud Shadow on Surface Strength	The strength of the shadow on opaque and transparent meshes. Disabled when 0.

Moon Light

Intensity	Maximum illumination from the light in lux.
Light Color	Filter color of the light. Note that this can change the light’s effective intensity.
Temperature	Color temperature in Kelvin of the blackbody illuminant. White (D65) is 6500K.
Volumetric Scattering Intensity	Intensity of the volumetric scattering from moon. This scales Intensity and Light Color.
Atmosphere And Cloud
Atmosphere Disk Color Scale	A color multiplied with the moon disk luminance.
Cloud Scattered Luminance Scale	Scales the lights contribution when scattered in cloud participating media.
Cloud Shadow Strength	The overall strength of the cloud shadow, higher value will block more light.
Cloud Shadow on Atmosphere Strength	The strength of the shadow on atmosphere. Disabled when 0.
Cloud Shadow on Surface Strength	The strength of the shadow on opaque and transparent meshes. Disabled when 0.

Exponential Height Fog

Fog
Fog Density	Global density factor of fog.
Fog Height Falloff	Height density factor, controls how the density increases as height decreases. Smaller values make the visible transition larger.
Fog Inscattering Color	Fog Inscattering Color.
Fog Start Distance	Distance from the camera that the fog will start.
Second Fog
Second Fog Density	Global density factor of secondary fog.
Second Fog Height Falloff	Height density factor, controls how the density increases as height decreases. Smaller values make the visible transition larger.
Directional Inscattering
Directional Inscattering Exponent	Controls the size of the directional inscattering cone, which is used to approximate inscattering from a directional light. Note: there must be a directional light with bUsedAsAtmosphereSunLight enabled for DirectionalInscattering to be used.
Directional Inscattering Start Distance	Controls the start distance from the viewer of the directional inscattering, which is used to approximate inscattering from a directional light. Note: there must be a directional light with bUsedAsAtmosphereSunLight enabled for DirectionalInscattering to be used.
Directional Inscattering Color	Controls the color of the directional inscattering, which is used to approximate inscattering from a directional light. Note: there must be a directional light with bUsedAsAtmosphereSunLight enabled for DirectionalInscattering to be used.
Volumetric Fog
Volumetric Fog Scattering Distribution	Controls the scattering phase function – how much incoming light scatters in various directions. A distribution value of 0 scatters equally in all directions, while .9 scatters predominantly in the light direction. In order to have visible volumetric fog light shafts from the side, the distribution will need to be closer to 0.
Volumetric Fog Albedo	The height fog particle reflectiveness used by volumetric fog. Water particles in air have an albedo near white, while dust has slightly darker value.
Volumetric Fog Emissive	Light emitted by height fog. This is a density so more light is emitted the further you are looking through the fog. In most cases skylight is a better choice, however right now volumetric fog does not support precomputed lighting, so stationary skylights are unshadowed and static skylights don’t affect volumetric fog at all.
Volumetric Fog Extinction Scale	Scales the height fog particle extinction amount used by volumetric fog. Values larger than 1 cause fog particles everywhere absorb more light.

Star Map

Star Map Brightness	Overall brightness of the Star Map.
Star Map Color Tint	Overall color tint of the Star Map.
Star Map Twinkle Intensity	Intensity of twinkling stars.
Star Map Twinkle Saturation	Saturation of twinkling stars.
Star Map Twinkle Speed	Twinkle speed of stars.
Star Map Horizon Threshold	Indicates how strong the star map can be faded into horizon. Lower values cause more stars appear at horizon.
Star Map Atmosphere Threshold	Indicates how strong the star map can be faded into atmosphere. Lower values cause more stars appear at brighter points in atmosphere, e.g. at daytime.
Night Horizon Color	Color tint of the horizon.
Night Zenith Color	Color tint of the zenith.

Weather FX

Rain
Rain Amount	Rain Amount.
Rain Color	Rain Color.
Rain Gravity Min	Minimum gravity of a single raindrop.
Rain Gravity Max	Maximum gravity of a single raindrop.
Rain Lifetime Min	Minimum lifetime of a single raindrop. Can affect the performance.
Rain Lifetime Max	Maximum lifetime of a single raindrop. Can affect the performance.
Rain Size Min	Minimum size of a single raindrop.
Rain Size Max	Maximum size of a single raindrop.
Rain Length Min	Minimum length of a single raindrop.
Rain Length Max	Maximum length of a single raindrop.
Rain Splash
Rain Splash Size Min	Minimum size of a rain splash.
Rain Splash Size Max	Maximum size of a rain splash.
Snow
Snow Amount	Snow Amount.
Snow Color	Snow Color.
Snow Gravity Min	Minimum gravity of a single snowflake.
Snow Gravity Max	Maximum gravity of a single snowflake.
Snow Turbulence	Snow turbulence.
Snow Lifetime Min	Minimum lifetime of a single snowflake. Can affect the performance.
Snow Lifetime Max	Maximum lifetime of a single snowflake. Can affect the performance.
Snow Size Min	Minimum size of a single snowflake.
Snow Size Max	Maximum size of a single snowflake.

Weather Material FX

Wetness
Wetness Amount	Wetness Amount.
Wetness Color	Wetness Color.
Puddles
Puddles Amount	Puddles Amount.
Puddles Color	Puddles Color.
Ripples
Rain Ripples Amount	Rain Ripples Amount.
Rain Ripples Intensity	Rain Ripples normap map intensity.
Rain Ripples Force Min Radius	Min Force Radius to write by the Rain Ripples Solver.
Rain Ripples Force Max Radius	Max Force Radius to write by the Rain Ripples Solver.
Rain Ripples Rings Number	Number of Rain Ripples Rings to propagate by a single raindrop.
Rain Ripples Rings Delay	Delay of Rain Ripples Rings propagation. Number represents Rain Ripples Solver frames to skip.
Rain Ripples Damping	Damping of Rain Ripples. Higher values are fading Rain Ripples faster.
Wind Ripples Intensity	Wind Ripples normap map intensity.
Wind Ripples Speed	Speed of the Wind Ripples.
Snow
Snow Amount	Snow Coverage Amount.
Snow Color	Snow Coverage Color.
Snow Intensity	Snow normap map intensity.
Snow Sparkles Threshold	Snow Sparkles Threshold. Lower values exposes more sparkles.

Wind

Volumetric Cloud
Low Cloud Wind Direction	Wind direction angle of Low Cloud layer in degrees.
Low Cloud Wind Speed	Wind speed of Low Cloud layer in m/s.
High Cloud Wind Direction	Wind direction angle of High Cloud layer in degrees.
High Cloud Wind Speed	Wind speed of High Cloud layer in m/s.
Cloud Noise Wind Direction	Wind direction angle of Cloud Noise in degrees.
Cloud Noise Wind Speed Horizontal	Horizontal wind speed of Cloud Noise in m/s.
Cloud Noise Wind Speed Vertical	Vertical wind speed of Cloud Noise in m/s.
Weather FX
Precipitation Wind Direction	Wind direction angle of precipitation particles in degrees.
Precipitation Wind Speed	Wind speed of precipitation particles.

Exposure

Exposure Compensation

Logarithmic adjustment for the exposure. Only used if a tonemapper is specified. 0: no adjustment, -1:2x darker, -2:4x darker, 1:2x brighter, 2:4x brighter, …

To be updated.

Changelog

V1.00

• Initial release

V1.01

• Deleted two legacy unused functions which were triggering an error “Explicit Category is required …” when packaging a build
• Moved Rain & Snow particle emitters from GPU to CPU, which fixes an error “Assertion failed: OnRequestDefaultDataInterface.IsBound() …”. This is probably an engine bug, deserves a further investigation. This can be just a temporary solution for now
• Default values to Rain & Snow particle count are reduced because CPU emitters are usually more expensive
• Fixed wrong material link in static mesh “SM_SC_SkySphere”
• Moved “Volumetric Cloud MID” variable in “Debug” Category
• Reverted to false default “Per Pixel Atmosphere Transmittance” boolean values to Sun and Moon (can cause “shadow zones” if surface is below Planet Top of Sky Atmosphere)

V1.02

• Fixed Moon disk direction when Sky Creator actor is rotated
• Fixed visual bug with long Cloud Wind Skew when editing clouds in editor
• Fixed Second Fog control in Exponential Height Fog
• Lowered default value for Cloud Shadow Extent from 50 to 25 in Sun & Moon (better cloud shadows with same performance)

V1.03

• Changed Volumetric Cloud material shading model to “Default Lit” instead of “Unlit” (makes no difference in UE4 4.26, but it does in UE5)
• Added engine major version verification when initializing FPlaceableItem in editor module (that struct is a bit different between UE4 and UE5)

V1.04

• Fixed Moon Disk sorting priority in sky material – stars are properly occluded now
• Fixed Moon Mask aliasing
• Fixed “Auto Scale” for Volumetric Cloud Noise
• Fixed “Cloud Wind Skew”
• Added “SkyCreator_CinematicController” blueprint specifically for Sequencer
• Added Moon Disk Rotation
• Added ability to choose between “Editor Weather Preset” and “Editor Weather Settings” – second option is for direct variable control
• Added two new quality options for Volumetric Cloud – “Ground Contribution” and “Multi Scattering Approximation Octave Count”
• Renamed “Sample Count Scale” subcategory to “Quality” in Volumetric Cloud options
• Renamed “Sync With Low Cloud Map Scale” variable to “Auto Scale” in Volumetric Cloud options

V1.05

• Fixed “Explicit Category is required …” in a Volumetric Cloud Materials struct when packaging a build

V1.10

• Enhanced Rain & Snow including many improvements
• New Rain Splashes effect
• Expanded Exposure settings supporting “Extended Luminance Range”
• Lower Hemisphere Color for Sky Light (useful for night lighting)
• Sun Light Intensity in Weather Settings is now “40.0”
• Moon Light Intensity in Weather Settings is now “0.02”
• Min Brightness for Exposure is now “0.02”
• Speed Up and Speed Down for Exposure are now “4.0”
• Fixed a typo in “Bottom Altitude” variable

V1.11

• New Cloud settings for Sun Light & Moon Light
• New Star Map Threshold settings
• New Star Map Twinkle settings
• Added “Use Editor Time of Day” & “Use Editor Weather Settings”
• Commented all visible variables
• Unclamped variables where it was unnecessary
• Added missing line “Super::GetLifetimeReplicatedProps(OutLifetimeProps)” to the replication function

V1.12

• Displaying debug variables now can be turned off by a checkbox “Show Debug Variables”
• Changed default “Fog Inscattering Color” from black to dark blue color (improves lighting at nights)
• Modified ConstructorStatics calls in SkyCreatorActor.cpp
• Added missing “Lower Hemisphere Color” parameter in the “Lerp Sky Light Settings” function
• Fixed empty reference in “MI_SC_SkySphere”
• Fixed empty reference in “MI_Demo_01”
• Fixed “ObjectProperty is not initialized properly” warnings
• Fixed casting static shadows from Compass mesh

V1.20

• Added dynamic Occlusion Capture
• Added new Weather Material FX – Wetness
• Added new Weather Material FX – Puddles
• Added new Weather Material FX – Ripples (including built-in Ripples Solver)
• Added new Weather Material FX – Snow
• Added new blueprint “SkyCreator_CaptureDistantOcclusion”
• Added new blueprint “SkyCreator_DebugOcclusion”
• Debug category is now deprecated – now all debug variables are placed at corresponding categories. They are still not visible by default, but can be turned on by “Show Debug Variables” checkbox
• Updated “SkyCreator_ControllerExample” – now it has Accumulation/Dry timers for the new Weather Material FX
• Updated Demo map
• Updated default Weather Settings to be slightly more pleasing to the eye
• Updated all Weather Presets and added a few more
• Updated Rain material to be slightly more soft looking

V1.21

• Added Real Sun & Moon Positioning
• Moved all Sun & Moon position settings into new single category “Sun & Moon Position”
• Reworked “Light Transition” hardcoded feature. Transitions between Sun & Moon are noticeably smoother now
• Direction of the North has changed from Y- to X+ to match Unreal’s yaw angle rotation
• Disabled Cloud Shadows of MoonLight component by default
• Fixed wrong color conversion with Volumetric Fog Albedo in Weather Settings
• Minor changes to code to have UE 5.0 Preview compatibility

V1.22

• Added Camera Velocity Alignment effect for Rain FX
• Added Moon Phase Light Intensity Scale
• Moon Disk color (or “Atmosphere Disk Color Scale”) is now independent of Moon Intensity and Moon Light Color
• Precipitation FX is now rendered before DOF
• Increased default Rain Splash amount x2
• Fixed crash when trying to change Sun or Moon Position Type variable of a blueprint child of Sky Creator
• Fixed Rain Splash fading

V1.23

• Added GPU Precipitation Particles feature
• Added Motion-based Alignment & Elongation for Precipitation particles
• Added Unified Gravity settings for Precipitation particles
• Added Constant Sun & Moon Intensity
• Redesigned Rain, Rain Splash and Snow materials (better blending with a scene and better visibility)
• Deleted “Distant Precipitation” feature (replaced by GPU Precipitation)
• Deleted “Index of Refraction” settings
• Deleted “Rain Length Min” and “Rain Length Max” variables are obsolete now
• Replaced “Gravity Min” and “Gravity Max” with a single “Gravity” variable
• Renamed “Camera Velocity Alignment” to “Camera Motion Alignment”
• Changed “Snow Spawn Rate Max” default value to 1000
• Changed some minor default weather preset settings
• Declared some functions as virtual
• Fixed Occlusion Capture not happening at the level load
• Fixed “Niagara Shader Module Delegate Never Set” crash in packaged builds