V.I.P 5.7 5.6 5.5 BP Ultra Dynamic Sky v9.2

Version 9.2 is going up today. Here are the changes:

• Added options to UDS and UDW for "Sky Configuration Override" and "Weather Configuration Override". You can select a configuration asset (authored with the Configuration Manager) for UDS or UDW to directly reference for its configuration. This way for example you can have UDS instances in different levels that reference a shared configuration asset which you can edit in one place.,
• UDS cloud shadows can now render into the light function atlas in a usable way. Note of course that with volumetric clouds, shadows in the atlas will extend above the cloud layer, as the atlas is just a 2D representation of the real light function. For the same reason, note there is no support for the water caustics in the atlas.,
• Reworked how Daylight Savings Time start and end days are configured. They're controlled by days of the week counted into the month, for example the second Sunday of the month, or the last Friday of the month. This allows DST start and end to properly vary from year to year. Also added support for the end hour being different from the start hour.,
• Location Presets on UDS in the Simulation category now also control daylight savings time settings, toggling DST and setting the start and end timing to be correct for the location,
• Added a utility, Configuration Buttons, which can be used to pin buttons for sky and weather configurations to a compact panel, for quick access in the level editor.,
• Added a setting to control the volumetric fog extinction of the global volumetric material, in spaces masked by the weather mask,
• Added an Automatic option for Control Point Location Source on UDW, which determines the source using Project Mode on UDS (pawn location for games/realtime, camera location for offline/cinematic). This Automatic option is the new default.,
• Added a function to UDS to output the current month as a string,

• Simplified controls for Screen Space Light Shafts on UDS. Scale, Max Brightness, and Bloom Threshold are now exposed as single values, to avoid a renderer issue in recent engine versions with changing light shaft settings on directional lights at runtime.,
• Added an option to UDS, Correct Specular Scale For Low Angle Cloud Shadows, which can reduce specular scale when the light is very low in the sky among partial cloud coverage, to help work around situations where the directional specular can appear mismatched with the clouds.,
• Added an option to UDW to choose between multiple methods for lightning flash bloom/glow. You can choose between light shaft bloom, a post process material glow, or disable the effect. The post process material effect is the new default.,
• Added a function to UDS, Offset Time of Day by Hours, which can offset time forward or backward by a number of hours, adjusting the date as needed.,
• Added a function to UDS, Offset Time by Time Span, which can offset the time and date values using a Time Span struct,
• Added an option to UDS, a string array called Disable Cvar Control, which can be used to disable UDS/UDW's control of specific cvars if needed,
• Improved behavior of the "Clouds Move with Time of Day" option, to be more responsive to fast changes of time and be previewed in the editor.,
• Improved the look of the inside cloud fog post process effect, with colors more consistent with cloud lighting and directional inscattering,
• Adjusted UDW random weather logic so if all potential presets are ruled out by the limiters (repeating type, extreme cloud coverage change, etc) it will fall back to the unfiltered map.,
• Fixed support for southern hemisphere Daylight Savings Time, where the start time is later in the year than the end time.,
• Fixed a sprite element of the Obscured Lightning effect not rendering correctly,

• Fixed Simulation sunset/sunrise event dispatcher timing not updating if date is changed at runtime in certain ways,
• Fixed Weather Override Volume temperature ranges not updating with an instant change of Season on UDW,
• Fixed post process priority not always being previewed on sky modifiers correctly when working in the sky modifier editor,
• Fixed daylight savings time making time jump forward or back one hour in some contexts where it shouldn't,
• Fixed weather mask tools blocking surface snapping in the editor,
• Fixed random weather variation state not replicating to a late joining client, if enabled on startup and later disabled,
• Fixed screen droplets not clearing on PIE if editor was showing rainy weather and the starting weather is not rainy,
• Fixed high puddle coverage causing puddle interaction sounds/particles against slopes without puddles,
• Fixed lightning flash target offset not being controlled correctly by the random seed,
• Fixed configuration manager sometimes making thumbnails with incorrect exposure,
• Fixes to widgets to support project setting "Explicit Canvas Child ZOrder",
• Fixed rain splash particles culling incorrectly in path tracer,
• Fixed Night Brightness not scaling in Simplified Color mode correctly,
• Fixed random weather instant update on season change not working as intended,
• Fixed Screen Frost rendering in front of a camera manager fade to black,
• Fixed cubemap selected for Custom Cubemap sky light mode sometimes not loading in,
• Fixed static clouds lighting angles not updating correctly with static clouds rotation speed

1. Version 9.1 is out today. Here is the change list:
   • UDS and UDW configurations, authored with the Configuration Manager, can now be applied at runtime with new "Apply Sky Configuration" and "Apply Weather Configuration" functions on UDS and UDW. Configuration assets are now saved with new classes to make this possible. The Configuration Manager will handle converting your existing configs to the new classes when you open it for the first time.,
   • Added the option for a Sky Modifier to apply its own post process settings. Can be configured from the Sky Modifier Editor.,
   • Added support for multiple cloud paint containers in a level and changing between them. You can make as many cloud paint containers as you want in a level, and the Volumetric Cloud Painter will prompt you to pick one when you open it. Cloud paint containers now also have an Active variable to set if the container will be used by UDS, with Activate/Deactivate functions to toggle if the container is active at runtime.,
   • Added a new setting for volumetric clouds, Cloud Formation Z Shift, which can shift cloud formation with height within the layer. To support this, the cloud formation texture is now a volume texture with formation changes in the Z channel. The default look of the clouds is unchanged, but this allows for another dimension of variety in potential cloud shapes.,
   • Added settings to Basic Controls on UDS for "Lighting Brightness" which handles scaling directional balance and sky light intensity together, to scale scene lighting relative to sky colors in a unified way.,
   • Simplified the Post Processing category on UDS. The logic for post process components will now detect when an entry doesn't use any of the Disable toggles and apply it without updating dynamically, eliminating the need for the separate Static Post Process Settings variable. Existing configurations which used the static settings will have them automatically moved to an entry in Post Process Components.,
   • Made some adjustments to make it possible to create a seamless looping animation of volumetric cloud movement. There is a new documentation entry which walks through how to configure for that.,
   • Added logic to allow random lightning flashes to strike actors in the level. This is achieved with a blueprint interface you can add to your actors. See the Lightning documentation entry for info on the setup.,
   • Improved integration of water caustics and the water fog values applied through the global volumetric material. If both features are enabled, caustic rays will be implemented through the global volumetric mat to cast appropriate light rays through the water, avoiding the present engine limitations of light function sampling in volumetric fog.,
   • Added a setting to control the height falloff for the water fog values,
   • Added settings to individually offset the falloff for the water caustics and water fog values,
   • Added an input to Test Actor For Weather Exposure to directly control the trace channel used for the queries,
   • Added a Weather Exposure Trace Channel variable to the Actor Weather Status component to set what trace channel it uses when querying the scene,
   • Added an option to toggle off the previewed cloud movement in editor,
   • Added empty functions to render target drawing logic on UDS/UDW, which can be overridden to allow custom drawing behavior to be added.,
   • Added an event dispatcher to UDS called when a time transition completes (started by Transition Time of Day),
   • The Actor Weather Status component will now respond to an instant weather change with an immediate refresh of its status,
   • Some optimization of DLWE snow/dust trail drawing,
   • Improved Night Brightness behavior to avoid lighting issues during the transition at dawn/dusk,
   • Some optimization of texture memory use for UDS/UDW,
   • Improved behavior of time based event dispatchers on UDS when time is changed instantly,
   • Improved consistency of effects on UDW updating instantly after any instant weather change,
   • Improved cloud rendering clarity/reduced noise when looking at clouds directly above,
   • Fixed an issue with the volumetric cloud material which could produce different cloud noise in the left and right eyes in VR,
   • Fixed for a warning message appearing when using Adjust for Path Tracer in 5.6,
   • Fixed UDW sound effect volumes not being affected by volume/LPF settings on an audio volume,
   • Fixed lightning flash cloud light element not scaling its lifetime with the lightning flash duration setting,
   • Fixed uneven cloud speed on begin play when Clouds Move With Time Of Day is enabled,
   • Fixed moving fog effects flickering in editor on reconstruct, when cloud speed is set to 0.,
   • Fixed starting modifiers sometimes not applying on begin play if Preview Starting Modifiers in Editor is disabled.,
   • Fixed UDW sound effects having noise/crackling artifacts when a global pitch modification is applied to game audio,
   • Fixed weather changes over volumetric cloud layer incorrectly disabling interaction effects,
   • Fixed configuration manager sometimes not applying time/date variables when changing toggles which can control time/date variables.
   
   
2. 
   
   

9.0B hotfix is out now, with a few more fixes for 9.0:

• Fixed readme utility search function not working from home screen,
• Fixed cloud speed briefly being too fast/slow if using random weather variation with random weather on begin play.,
• Fixed rain and snow getting too little ambient light in path tracer renders,
• Improved interpolation logic between day and night values for Space Layer Brightness

Small hotfix release today, v9.0A, to fix a few issues in 9.0:

• Fixed UDW causing levels to show as having unsaved changes incorrectly when weather effects are active in the editor viewport when level editor tick is enabled.,
• Fixed Cloud Light Color tint settings for simplified color not being applied to 2D/static clouds as intended.,
• Fixed a warning message about a missing file when starting some weather effects in PIE

Version 9.0 for 5.5 and 5.6 is released today. Here is the changelog:

Sky:
Simplified Color has been reworked. It now very closely matches the sky atmosphere in most contexts with default settings, while still being adjustable with its color tint settings in the same ways as before. Note the old approach with the atmospheric scattering LUT texture has been replaced with sun and moon LUT volume textures formatted differently.,
Since changes in 5.5 made the cloud rendering mode UDS exposes as "Background Only Clouds" not strictly limited to the background anymore, the names and descriptions of the volumetric cloud rendering modes have been rewritten to better communicate their behavior in 5.5.,
Feature Levels on UDS for "Mobile Forward" and "Mobile Deferred" have been combined into one Mobile option. The system now sees if forward or deferred is in use by querying the project configuration.,
Improved logic for Directional Lights Absent Brightness, to get more consistently scaled brightness with different modes and settings,
Added an option to the Space Planet struct to make the planet render as just a ring around the local planet. A new planet preset is included as an example.,
Improved behavior of path tracer fog post process in heavy fog, when used with volumetric fog enabled,
2D Cloud Shadows will now project at an angle consistent with the sun/moon orientation, instead of straight down by default. This is adjustable with a new setting in Cloud Shadows.,
Some changes to reduce rendering artifacts with volumetric fog and volumetric clouds together,
Added a static overcast sky texture to the static clouds for more natural overcast skies in that mode. The texture can be adjusted or replaced in the Static Clouds category.,
Some improvements to coloring/lighting on static clouds,
Added an option, enabled by default, for Static Clouds to fade opacity down for clear skies.,
Added settings to the global volumetric fog material on UDS to add extra global extinction from rain/snow/dust.,
Added an option to UDS to force the sky material to sample the DBuffer for the space layer, even if no planets/moons/nebula are enabled.,
Exposed a setting to control the update period for cloud movement,
Added a warning message if the project uses a project setting which breaks fog colors,
Added a setting for "Exposure Bias Dawn/Dusk" to exposure settings on UDS,
Cleaned up some alpha edge artifacts from included static clouds textures,
Fixed a few variables on UDS not being included in saved configurations,
Fixed the conflicts which could be caused by assigning one sky modifier to multiple weather presets transitioning between each other.,
Fixed volumetric cloud painting textures sometimes not drawing in when opening a level for the first time in the editor.,

Weather:
Added a system for Environment Sound to UDW. This is built to help with setting up general ambient audio which changes with time and weather, and is affected by UDW's full directional sound occlusion. Its set up for users to author their own Environment Sound assets, and a function call on UDW can enable/disable and transition between them at runtime.,
Added functionality to UDW to periodically spawn Radial Storm actors, positioned and animated so they pass over the player's location. This can be enabled and configured in a new Radial Storm Spawning category.,
Added new functionality to UDW for wind gusts. Wind can vary intensity using a stream of noise, for more natural randomized gusts/lulls in wind. You can scale the intensity and speed of that noise with settings in a new Wind Gusts category.,
Added a new widget blueprint, UDW Current Weather Display, which can display the current weather from UDW, either as an icon or text description.,
Reworked UDW support for a Wind Directional Source. Instead of linking to a Wind Directional Source actor, UDW will construct a Wind Directional Source component, if "Enable Wind Directional Source" is turned on, which it is by default. There's also an option for "Disable Directional Source Speed in Interior", useful for example when the wind directional source is only being used to affect chaos cloth on the player character.,
Added an option for UDW to apply a camera shake when the camera is exposed to heavy winds. Found in a new Wind Camera Shake category, disabled by default.,
Added a function to UDW, Get Wind Speed in Real Units, which outputs approximated values for wind speed represented in Knots, MPH, and KPH.,
Made a new version of Dynamic Landscape Weather Effects (V3) which uses a material attributes pin for its input and output, similar to Surface Weather Effects. It also has some new inputs for adjusting behavior with nanite tessellation displacement. The V2 function is still included for now, for legacy support.,
Added a setting to determine if UDW will derive Season from date as meteorological seasons or astronomical seasons. The default is now meteorological seasons.,
Added deterministic control for the weather particles on UDW, controlled via the Random Seed setting in Basic Controls.,
Added a Height Falloff option to the Weather Override Volume to have its effect on weather state fade out either above or below its Z position.,
Rain and Snow particles now get their ambient light from the translucency volume. Their ambient light variables still exist, but are called "extra ambient light" and default to 0.,
Reworked how sound occlusion and spatialization is applied to weather sounds. The global and directional weather sound sources now output to an audio bus which a metasound source called Weather Sound Mixer applies directional occlusion and stereo panning to. Allows additional sound sources (like the new environment sound system) to have the same effects applied to them without additional cost.,
Added a Season Debug to the Season category on UDW, to more clearly convey how the Season float value is interpreted.,
Added an option to Material Effects on UDW to shift snow/dust coverage with the wind direction,
Exposed sound source assets for UDW sound effects to variables in the Sound Effects category,
Added an option for Heat Distortion to use the localized temperature (from the player occlusion location) instead of the global temperature.,
Removed the volumetric fog particles option from UDW. If you've been using this feature, I would recommend using the global volumetric material, configured on UDS. It can achieve similar results of volumetric fog extinction moving with the weather effects, and much more efficiently.,
Added a master volume control for all the weather sound effects.,
Changed Movement Update Threshold on Radial Storms to be entered as a fraction of Outer Radius,
Added a variable to DLWE Interaction Settings to control the object types queried for when testing for landscape collision,
Added an option to the Temperature Volume to replace the temperature inside the volume with a direct value.,
Added "Getting Foggy" and "Fog Clearing" event dispatchers to UDW,
Improvements to DLWE snow/dust normal behavior on static meshes,
Added an input to the DLWE function to scale a windswept normal texture aligned to wind direction,
Added functions to UDW to directly toggle on/off entire features at runtime (each type of weather particles, sound effects, screen effects, etc),
Removed the legacy "Wet Weather Effects" and "Snow and Dust Weather Effects" material functions,
Added a variable to the Wind Physics Force to define what bone to apply the force to if the parent is a skeletal mesh.,
Added simple white alpha masked versions of the weather preset icons, linked as a new variable in the data assets.,
Fixed a bug with change weather transitions in progress being applied as part of a save structure not affecting the clients correctly in multiplayer,
Fixed rain drip spline icicles not being affected correctly by WOV material target,
Fixed puddle normal ripples not rendering correctly on mobile,
Fixed applying a saved UDS state not correctly affecting random weather changes in progress,
Fixed cloud movement direction not immediately updating at runtime if wind direction on UDW changes with no other weather changes.,

Shared/Tools:
Changed Configuration Manager so it can gather config assets from any folders, not just the ones it saves to. Also added text to config thumbnails indicating the version of UDS they were saved with (applies to new configs saved moving forward),
Added a slider to scale the interface and text in the documentation utility, and made it so right clicking images will open them in a browser.,
Many variables on UDS and UDW now represent the units they use,
Added mobile support for features: Space Layer, Weather Masks, DLWE Snow/Dust Trails, WOV Material Target,
Made the Mini Controls utility show controls for date, if UDS is using Simulate Real Sun.,
Added "Hide Sky" and "Hide Weather" functions to UDS and UDW, to act as a simple way at runtime to hide/show the actors or specific elements like lights, fog, weather particles, etc.,
Added an entry to documentation about how to install updates for UDS,
Visual refresh to the UDS/UDW actors appearance in editor,
Fixed editor preview of player occlusion sometimes not behaving the same as runtime, and not reaching full occlusion,
Fixed errors which could happen when using occlusion portal components in some streaming/world partition contexts

8.6A hotfix with a few bug fixes for 8.6, out today:

• Fixed Static Clouds Authoring Tool producing broken results in 5.5
• Fixed clients not always starting with the server's weather in 5.5 if random weather variation is used with "Begin Play Weather Is Random" enabled.
• Fixed sky light time slicing cvar only being set at runtime
• Fixed runtime changes from Space sky mode to others causing broken real time sky light capture

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8.6B hotfix out today. Here are the changes:

• Fixed sky modifiers added on the same frame UDS starts up not animating correctly if they have a non-zero fade in time.
• Fixed icicle mesh LOD distance issue in 5.4 and 5.5
• Fixed color based fog directional inscattering being too dark in 5.5
• Fixed "Ambient Sound Time and Weather Controlled" fading in/out on startup when it shouldn't
• Fixed random weather forecast array not being available immediately if "Begin Play Weather Is Random" is disabled.
• Fixed translucent icicle material not compiling on mobile
• Added a setting to the sky light category to control the cvar "r.SkyLight.RealTimeReflectionCapture.TimeSlice.SkyCloudCubeFacePerFrame". This is mainly to apply a default value of 1, to avoid an engine bug in 5.5 which can happen when this value is higher than 1.
• Changed Weather Mask class to use a timer for its fade behavior, to avoid an issue if the project has "Can Blueprints Tick By Default" disabled
• Added a trace channel input to the "Check If Point Is Exposed to Sun or Moon Light" function
• Added a setting to control the cull distance for drip particles on a Rain Drip Spline actor

8.6 is up now, for 5.1 to 5.5. Make sure to update using the launcher. The fab plugin cannot update an asset pack. If the launcher doesn't prompt the update or list compatibility correctly, use Remove Local Content on UDS to force it to redownload latest when you add. Here is the change list:

• Added the option for Weather Mask Brushes to use a manually painted texture instead of the simple brush shapes, and a utility for painting them called the Weather Mask Brush Painter.
• Added a new feature to the Rain Drip Spline to render icicle meshes hanging from the spline, scaled with material snow coverage from UDW
• Added a new event dispatcher to UDS called "Custom Time". This uses an array of floats in the Animate Time of Day category. If the user adds values to this array, each one will be used to call the dispatcher, when Time of Day passes that value at runtime. The event outputs the index of which time in the array caused the call.
• Reworked how high frequency noise samples are distributed for volumetric clouds. They now distribute noise levels more effectively based both on both distance to the sample and camera field of view. The settings for high frequency levels and disable distance have been replaced with "High Frequency Noise Distance Scale" and "Max High Frequency Noise Levels".
• Added a function, Fade Mask Over Time, to the Weather Mask components. Call this function on the Weather Mask Brush or Weather Mask Projection Box at runtime to fade their mask values over a duration.
• Added a setting to scale aurora brightness in the sky light/global reflection environment.
• Added settings to adjust the velocity added to rain/snow/dust/wind debris from the current wind

• Added a bool variable to UDS, Fast Cache Toggle, which can be turned on selectively at runtime if performing a change/animation of cached properties which needs faster cached property updating.
• Added a Fog Noise Offset vector to UDS, to manually offset the volumetric fog noise samples
• Added a setting to control the framerate/speed of the SubUV animation for tiling water ripples on UDW material effects
• Added an option to make the lightning directional light on UDW stationary, so it can potentially use baked shadows, at the cost of only being able to spawn lightning flashes in one direction.
• Added an option to UDS to replace the volumetric cloud material. Mainly useful for selecting a modified copy of the UDS cloud mat.
• Added an optional emissive snow sparkle effect to Dynamic Landscape Weather Effects and Surface Weather Effects. Disabled by default.
• Added a setting to toggle off the UDS level editor toolbar dropdown
• Some improvements to deeper snow depth rendering with Dynamic Landscape Weather Effects and snow trails
• Improvements to distance field collision on weather particles handling of thin distance field walls
• Changed the User Friendly Name variable in UDS_Weather_Settings to a Text variable so it may be localized if needed
• Improved behavior of "Disable Height Fog Above Volumetric Cloud Layer" to be more seamless
• Increased the default of "Scale View Samples When Camera Is in Cloud Layer" to 2
• Made it so Adjust for Path Tracer enables sky light location updating and disables real time capture time slicing
• Made UDS and UDW skip some unnecessary update logic on dedicated servers and use a longer tick interval there by default, exposed as Dedicated Server Tick Interval.

1. • Adjusted tiling stars texture sampling to avoid aliasing with FXAA or MSAA
   • Fixed manual weather sliders in Onscreen Controls not updating with the weather state changes
   • Fixed Weather Override Volume spawned on server sometimes not replicating Runtime Spline Points to clients before they start up
   • Fixed Hourly event dispatcher calling for every hour between the old time and new time when applying a saved UDS/UDW state
   • Fixed a bug with the Date Changed event dispatcher and saving and loading on UDS when using negative year values, due to limitations of the unreal datetime structure
   • Fixed random weather variation forecast not working for starting random weather
   • Fixed some snow particles showing line artifacts when snow particle ambient light is turned up very high
   • Fixed outer radius and inner fraction not replicating to clients from the radial storm
   • Fixed volumetric fog albedo settings being applied to height fog component without appropriate SRGB correction
   • Fixed for Puddle Fluid Volume causing an editor crash in 5.5 if configured with a very high grid density
   • Fixed an issue where the moon texture alignment could get flipped when Simulate Real Moon is on
   • Fixed Weather Mask Target Size having an unintended effect on Weather Mask Projection Box blur radius
   • Fixed for a renderer crash in 5.5 if using DLWE snow trails with forward shading

8.5 is up today, for 5.1 to 5.5. Here is the change list:

• Added a new Sky Modifier Editor utility, a tool for creating and working with sky modifier assets
• A sky modifier can now be selected on a weather preset asset directly, and it will be applied to UDS based on how that preset is affecting local weather. Associating custom presets with sky modifiers allows weather to effectively take control of anything on UDS exposed to the sky modifier system.
• Added an Ultra Dynamic Sky level editor toolbar menu, with shortcuts to UDS tools and utilities.
• Added an option to scale Simulation Speed at night
• Added an actor component, UDS Client Controller, which can be added to a Player Controller to provide replicated events for the client to send time/weather changes to the server. The Onscreen Controls widget will automatically make use of this from a client, if the component exists on the player controller.
• Added a color variable to tint sun disk color
• Expanded the properties which can be controlled by the Sky Modifier system
• Added a new Nebula effect to the Space Layer category on UDS, for rendering a layer of noise based nebula into the space layer
• Exposed weather particles' visibility to raytracing to a setting in Shared Particle Settings, off by default. Bypassed if Adjust for Path Tracer is enabled on UDS.
• Changed the Space mode to allow Night Sky Glow to affect sky color in that version of the material.
• Fixed rain splash particles spawning against surfaces at incorrect normals relative to general rain velocity
• Fixed wind direction variation going out of sync on multiplayer clients
• Fixed for a renderer bug which could cause the Space mode to render with a black horizon in some project templates
• Fixed issue with "Clouds Move with Time of Day" causing sudden cloud movement at midnight
• Fixed for an editor crash when opening the puddle ripple niagara system in 5.4 with RT features enabled in DX12.
• Fixed weather particle spawning issue when the player camera is pointed exactly straight down
• Removed some circular class dependencies between UDW and its components, to help avoid a new engine crash specific to some packaging settings in 5.5
• Fixed for a material compilation error when cooking for android in some contexts
• Made UDW apply a cvar by default in 5.5 to avoid GPU niagara emitters taking a long time to cache and start working on first launch of a packaged build. Toggled as part of Apply Version Specific Correction.
• Fixed Onscreen Controls manual weather sliders sometimes not responding to clicks
• Fixed obscured lightning not being disabled consistently by its toggle

Version 8.4 is out today. Here is the change list:

• Added an option to Shared Particle Settings on UDW to apply a custom weather particle camera transform. If true, vector variables for a custom camera location and forward vector will be used instead of player camera 0. Can be used to place the weather particle systems spawn area in any location if needed.
• Improvements to DLWE snow trail rendering. Trail edges now have a soft piling normal effect in a radius around compressions. This is specific to Shader Model 6.
• Added an option to UDS Occlusion Settings to have player occlusion use GPU distance field traces, instead of the simple collision traces on the CPU.
• Added an element to the rain particles for small impact ripples from raindrops on surfaces. Toggled by a setting in Rain Particles, and enabled by default.
• Changed UDW Thermometer to use basic letters for its scale display instead of the special ℉ and ℃ characters, for compatibility with fonts that lack those characters
• Added a function to UDW, Generate Weather State at Location, which can be called to create what would be the local weather state if the player was in a custom input location. Can be used to query the specific weather at any location in a level.

• Added a setting, Splash Minimum Z Normal, to adjust the angles of collision which rain splash particles can spawn against. The new default allows splashes and splash droplets to happen against more vertical surfaces.
• Added support for rain drop decals and splash droplets to the distance field collision version of the rain
• Made it so sampling temperature from UDW at a custom location will take local sources of weather at that specific location into account in addition to interior temperature and temperature volumes.
• Made it so distant lightning bolts can appear in a path tracer render, when Adjust for Path Tracer is enabled.
• The weather particles warmup on begin play is now toggled by an option in Shared Particle Settings, and is disabled by default.
• Added a function to UDW, "Impact Snow/Puddle/Dust at Location" which can be used to manually do a one shot interaction with the DLWE snow/dust/puddles and Puddle Fluid Volumes.
• Added an option to UDW to scale lightning bolt ribbon width
• Exposed Transmission on the Sun and Moon lights to a toggle in the Sun and Moon categories.

• Changed the pure UDS and UDW references in the Custom Weather Behavior function to be Actor references, to avoid an engine bug with class reference loops in data assets. Children using these references will need to use interfaces or casting to conform to the change.
• Fixed an issue with Weather Override Volumes loading/spawning at runtime, keeping them from affecting weather/material state correctly in some contexts
• Fixed errors from the DLWE Interaction component when its settings for snow or puddle sound effects are disabled
• Fixed post process wind fog disappearing in the level editor after ending a PIE session
• Fixed manual weather state overrides not being applied in editor if Level Editor Tick is disabled.
• Fixed rain drip spline sometimes only spawning particles at the start of the curve
• Fixed weather effects of radial storms not affecting temperature calculation correctly
• Fixed an issue with post process wind fog when partially occluded in a camera with a very wide field of view
• Fixed an issue where snow trails could draw lines incorrectly when snow weather starts suddenly
• Fixed an issue with some active properties on UDS not updating completely to match new conditions with some fast changes of weather.
• Fixed an issue with the Configuration Manager applying unintended manual weather overrides to UDW when applying sky configs

Small hotfix for 8.1 is out today. Here are the changes:

• Fixed issue with sound occlusion not ignoring pawn collision on players other than first player
• Fixed bug with cloud shadows which could happen when opening and closing the onscreen controls widget
• Adjusted settings on metasounds assets to avoid a potential metasound bug causing incorrect culling of audio channels for weather sounds