kevinpbuckley UDS modifiers, configurations, state, and misc features
The "extras" layer of UDS: packaging, saving, and applying state; per-context post-processing; interior detection; water; sounds; on-screen UI; and the sun lens flare. Each system is independent — pick the section that applies.
| System | Category on UDS | Mental model |
|---|---|---|
| Sky Modifiers | Modifiers | Data-asset property overrides that fade in/out and layer |
| Configuration Manager | (editor utility) | Snapshot/restore the entire UDS settings state as an asset |
| Save UDS+UDW State | (function pair) | Pack/unpack state into a struct for save data |
| Sun Lens Flare | Lens Flare | UDS's own filmic flare on the sun |
| Post Process Components | Post Processing | Time/weather/interior-driven post components |
| Interior Adjustments | Interior Adjustments | Sky/fog/light changes when camera is occluded |
| Player Occlusion | Player Occlusion | The trace/volume system that drives interior detection |
| Water Level | Water Level | Caustics, underwater fog, sound, weather particle masking |
| AmbientSound — Time and Weather | (actor class in Blueprints/Sound) | Drop-in ambient sound that auto-volumes with day/night and weather |
| Onscreen Controls | (widget in palette) | Drop-in UI for player time/weather control |
When to use this skill
- Saving the current UDS look as an asset; applying a different one at runtime.
- Persisting sky/weather state across save/load.
- Layering temporary visual treatments (combat tint, slow-motion vignette) onto UDS.
- Post processing that changes with time of day, weather, or being indoors.
- A scene that needs different fog/light when the player enters a building.
- A water level affecting fog/caustics/sound/weather underwater.
- Letting players control the sky from in-game UI.
- Modifying UDS logic without losing changes on updates (child blueprints).
Sky Modifiers
Data assets that override a selection of float/color properties on UDS, plus post-process settings. Can be added/removed at runtime, faded in/out, and layered.
Authoring modifier assets
Launch the Sky Modifier Editor:
- Ultra Dynamic Sky dropdown on the level editor toolbar, or
- Run the editor utility at
Blueprints/Tools/
In the editor:
| Action | What happens |
|---|---|
| Open | Open an existing modifier asset |
| New | Blank modifier placed in Blueprints/Sky_Modifiers/ (movable afterward) |
| Edit a Modifiable Sky Property value | Modifier takes control of that property |
| Click checkbox next to a property | Remove the property override from this modifier |
| Modifier Settings → easing, max alpha, post-process toggles | Per-modifier behavior |
The current modifier previews live on UDS while you work.
Applying modifiers
| Where | How |
|---|---|
| Modifiers category on UDS | Add a modifier to be used from level start |
| Runtime functions on UDS | See table below |
| Function | Behavior |
|---|---|
Add Modifier(modifier, fadeIn) |
Add and fade in over fadeIn seconds |
Remove Modifier(modifier, fadeOut) |
Fade out an applied modifier and remove |
Set Modifier State(modifier, alpha) |
Set alpha directly and freeze it. Doesn't change on its own. Adds if not already applied. |
Clear Modifiers() |
Instantly clear all applied modifiers |
Set Unmodified Property Values() |
Resave current applied properties as the new unmodified baseline (used as the from/to for future modifier interpolations) |
Time-of-Day-specific modifiers
In Sky Modifiers category, the Time of Day Specific Modifiers map auto-applies modifiers within Time of Day ranges:
- Add a modifier to the map; expand the dropdown for its fade range.
- Configure fade in across one TOD range and fade out across another.
- Fade-in can occur before or after fade-out — useful for overnight modifiers. Just ensure end > start for each fade.
Don't drive a time-controlled modifier with Add/Remove/Set Modifier State — they'll conflict.
Configuration Manager
Save the complete configuration of every UDS (and UDW) setting as a config asset, for reuse across levels/projects or runtime application.
Launch the Configuration Manager:
- Ultra Dynamic Sky dropdown on the toolbar, or
- Run the editor utility in the Blueprints folder
| Action | What happens |
|---|---|
| Select existing config | Apply it to your UDS actor |
| Save (bottom-right, when nothing selected) | Create new config; prompts for name + location |
| Save to project files | Placed in Ultra Dynamic Sky/ folder in your project (per-project) |
| Save to engine content folder | Placed in Ultra Dynamic Sky/ folder there (per-engine-version, shared across projects) |
The version number in each config's thumbnail corner is the UDS version it was saved with. Older configs still load but won't contain data for new variables. Re-save them with current UDS for complete data.
Applying configs at runtime
| Function | Where |
|---|---|
Apply Sky Configuration(config) |
On UDS |
Apply Weather Configuration(config) |
On UDW |
When applying both, apply the weather config first.
Configuration override (bind UDS to a config asset)
Point UDS or UDW at a config asset for settings to be entirely driven by that reference. Useful for shared configs across multiple levels.
| Where | Setting |
|---|---|
| Advanced dropdown of Basic Controls on UDS / UDW | Configuration Override |
With an override set, UDS/UDW settings can't be changed directly — the override owns them. Override applies on startup; at runtime you can still modify UDS/UDW variables as normal.
Configuration Buttons editor panel
For levels where you swap configs while working, pin Configuration Buttons — find in the Ultra Dynamic Sky dropdown on the toolbar. Add configs as buttons in a compact panel for quick swap.
Save / load state for save games
For save-game systems that persist sky/weather state across loads or sessions:
| Function | What it does |
|---|---|
Create UDS and UDW State for Saving() |
Returns a struct with all time + current weather state — pack into save data |
Apply Saved UDS and UDW State(struct) |
Apply on save load or level entry |
Sun Lens Flare
UDS's own filmic lens flare for the sun. Completely separate from Unreal's image-based lens flare post effect.
In the Lens Flare category:
- Enable
Enable Sun Lens Flare - Select a
Lens Flare Type
Custom lens flares
In the advanced dropdown of Lens Flare, set Custom Lens Flare Parent Instance to an instance you created from one of the existing material instances at:
Materials/Material_Instances/Lens_Flares/
Adjust textures, colors, and mapping parameters in your custom instance.
Post Process Components (time/weather-driven)
In the Post Processing category, the Post Process Components array — each entry becomes a post process component the system creates at startup.
| Per-entry control | Effect |
|---|---|
| Post process settings | Override any setting (bloom, color grading, vignette) |
| Time-of-day Enable/Disable checkboxes | Fade blend weight in/out as time changes |
| Mask Blend Weight options | Mask the component based on cloud coverage, fog, dust, interior occlusion |
| Raining / Snowing masks | Dependent on UDW (no effect without it) |
Use cases:
- Desaturated grade only at night.
- Harsher contrast only when overcast.
- Warm cozy color grade only inside.
Interior Adjustments
Adjusts fog and light based on how occluded the camera is by surrounding scene collision. Category: Interior Adjustments.
| Step | Detail |
|---|---|
| Enable | Apply Interior Adjustments |
| Configure | Tune the settings below it for interior look |
| Source of occlusion | The Player Occlusion system (below) |
| Force a region to be occluded | Place a UDS Occlusion Volume actor (Blueprints/Occlusion/) |
Occlusion Mode in the Player Occlusion category — whether occlusion comes from traces, volumes, or both.
Player Occlusion
The system on UDS that monitors how occluded the player camera/pawn is from the sky/weather. Drives:
- Interior Adjustments on UDS (above)
- Sound Occlusion on UDW — quiets/muffles weather sounds in interiors
- Optional Interior Temperature on UDW's temperature calculation
The Player Occlusion category sets how occlusion is computed: per-update time budget, trace count, collision channel, etc.
| Actor / component | Purpose |
|---|---|
UDS Occlusion Volume (Blueprints/Occlusion/) |
Force a region to be fully occluded; also can block weather particles (Simple Collision mode only) |
UDS Occlusion Portal (component) |
Around the sampling location, traced against; can negate occlusion when the trace is unobstructed. Use case: an open door/window letting outside weather sound in. |
Water Level
Sets the height of water surfaces in the level. Category: Water Level.
Used by:
| Feature | Toggle / setting |
|---|---|
| Water caustics on sun/moon | Render Water Caustics on UDS |
| Volumetric fog below water (extinction + albedo) | Part of Global Volumetric Material (see ue-uds-fog-and-atmosphere) |
| UDW applying water level to weather particles, sound occlusion | Use UDS Water Level in UDW's Water Level category |
| Variable | Meaning |
|---|---|
Global Water Level |
Universal minimum water Z (e.g. an ocean) |
Water Body Classes |
Actor classes whose meshes locally affect water level by rendering to a render target. Pre-configured for the Water plugin's Lake/Ocean/River. |
If water bodies stream in/out, call Update Water Level Target on UDS to force a refresh.
AmbientSound — Time and Weather Controlled
Actor class at Blueprints/Sound/AmbientSound - Time and Weather Controlled. Child of standard Ambient Sound — auto-adjusts volume by day/night and weather.
| Setting (top of Sound category on the actor) | Effect |
|---|---|
| Day / night volume multipliers | Per-time-band volume |
| Snowy / Rainy / No-weather multipliers | Per-weather volume |
Volume Multiplier Transition Time |
How long the volume change takes when conditions change |
For a fuller soundscape with sound occlusion, prefer UDW's Environment Sound system — see ue-udw-particles-lightning-wind-sounds.
On-screen sky controls widget
UDS Onscreen Controls widget in the widget designer palette under Ultra Dynamic Sky Widgets. Drop-in player UI for time/weather.
| Exposed setting | Effect |
|---|---|
Show Time Control, Show Weather Control, etc. |
Toggle off individual controls (e.g. for a compact time-only widget) |
| Time / date format | Display format |
| Weather presets available | What appears in the weather control |
Multiplayer use
For client-side Onscreen Controls driving server-side UDS/UDW state: add the UDS Client Controller component to your player controller class. Onscreen Controls automatically uses it from clients to replicate function calls up to the server.
Modifying UDS blueprints (survives updates)
For changing UDS logic itself: work in a child class rather than editing UDS directly — modifications survive updates.
1. Right-click UDS class in content browser
2. Create Child Blueprint Class
3. Override individual functions (e.g. Current Sun Light Color)
Some classes have empty functions specifically meant for override in children — e.g. Custom Volume Behavior on Weather Override Volume (see ue-udw-spatial-weather).
Gotchas
- Modifier and time-of-day specific modifier both applied to the same modifier — they conflict. Pick one mechanism.
Set Modifier Statedoesn't appear to work — the modifier wasn't applied first.Set Modifier Stateadds it automatically; if alpha looks wrong, you may be racing another modifier control call.- Config asset loads with missing values — saved with an older UDS version. Re-save with current UDS to fill in new fields.
- Can't change a UDS variable — configuration override is bound to a config asset. Either remove the override or edit the underlying config.
Apply Sky ConfigurationandApply Weather Configurationin the wrong order — apply weather first when applying both.- Sun Lens Flare confused with engine post-process lens flare — different system. UDS's Lens Flare is filmic and configured per Lens Flare Type in the Lens Flare category. Engine post lens flare is configured per post-process volume.
- Interior Adjustments fade in/out flickering — occlusion traces are unstable; tune Player Occlusion settings (trace count, update period) or place UDS Occlusion Volumes for stable interiors.
- Weather sounds quiet at wrong times — sound occlusion using Player Occlusion. Adjust trace behavior in Player Occlusion on UDS. (See
ue-udw-particles-lightning-wind-sounds.) - Underwater fog or sound not applying —
Use UDS Water Levelon UDW is off, orGlobal Water Levelis wrong, or per-body Water Body Classes aren't configured. - Onscreen Controls don't work for clients in multiplayer —
UDS Client Controllercomponent not added to the player controller. - Changes to UDS blueprint lost after a plugin update — modifications were made directly to UDS classes. Use child blueprints (see above).
References & source material
Docs (Ultra Dynamic Sky 9.5):
- Saving and Applying Configurations
- Sky Modifiers
- Saving the Sky and Weather State for Save Data
- Sun Lens Flare
- Interior Adjustments
- Player Occlusion
- Water Level (incl. Water Body Classes)
- Post Processing (Post Process Components)
- Ambient Sounds Controlled by Time and Weather
- On Screen Sky Controls
- Modifying UDS Blueprints
Plugin asset paths:
Blueprints/Tools/— Sky Modifier Editor, Configuration Manager, Configuration Buttons utilitiesBlueprints/Sky_Modifiers/— default home for new modifier assetsBlueprints/Sound/—AmbientSound - Time and Weather Controlledactor classBlueprints/Occlusion/—UDS Occlusion Volumeactor;UDS Occlusion PortalcomponentMaterials/Material_Instances/Lens_Flares/— material instances for Custom Lens Flare Parent InstanceUltra Dynamic Sky/(project or engine content) — default location for Configuration assets- Widget designer palette → Ultra Dynamic Sky Widgets —
UDS Onscreen Controls
Related skills: ue-uds-setup-and-modes (config override option lives in Basic Controls advanced dropdown), ue-uds-fog-and-atmosphere (Water Level drives Global Volumetric Material underwater extinction), ue-uds-performance-mobile-troubleshooting (Hard Reset Cache, Static Properties functions), ue-udw-setup-and-state (Apply Weather Configuration), ue-udw-particles-lightning-wind-sounds (Sound Occlusion uses Player Occlusion; Environment Sound system).