Snow

Weather reference

FXMasterParticle effectAPI type: snow

Falling snow with configurable movement and persistent snow-cover background support.

Weather effects can cover a full Scene or be limited to Regions. Configure the placement or movement controls exposed by the effect first, then tune its appearance, population, and optional background controls.

Reference	Value
Package	FXMaster
Effect kind	Particle effect
Category	Weather
Runtime type	snow
Exposed parameters	30

Airborne and settled snow

Within an enabled Snow effect, the airborne and Background layers are configured separately. The Background can build to full coverage without requiring the airborne flakes to become a whiteout, but disabling Snow disables both layers.

Airborne snow

Choose Top Down before adjusting Direction, Scale, Speed, and Density. The normal presentation shows drifting snowfall across a side-facing view; Top Down changes the motion and coverage for overhead maps.

Background snow

Background creates persistent snow coverage with immediate or timed fill, opacity, fill variation, drift height, and drift size. Configure the background after the airborne layer so the two remain visually balanced.

Token trails and refill

Token Trails removes a path through the accumulated snow. Trail Width and Trail Strength define the path, Refill Trails Over Time restores it over the configured Trail Refill Time, and Token Elevation Threshold prevents elevated tokens from affecting the surface.

Important controls

• Top Down: Switches Snow to the overhead presentation intended for top-down maps. This changes particle projection and movement, so set it before finalizing scale and direction.
• Direction: Sets the primary travel direction for snowflakes. Directional Spread can add variation around this angle.
• Density: Changes how many snowflakes are visible or spawned at once. It does not change their size.
• Background: Render a persistent settled-snow surface behind this effect. The surface follows the effect’s stack placement, scene or Region mask, Levels selection, and below-token/tile settings.
• Token Trails: Create visible background trails as tokens move through the surface. By default trails remain for the current canvas session; Refill Trails Over Time can gradually restore the background.

Setup notes

• Balance airborne Density separately from Background coverage while Snow is enabled.
• Background trails can expose paths through snow and optionally refill over a configured duration.
• Use the Token Elevation Threshold to prevent flying or elevated tokens from carving trails through the surface.

Bundled preset usage

Preset	API name	Availability	Variants
Snow	snow	FXMaster	Normal, Top Down

Parameters

The table combines the settings available for this effect in Scene and Region contexts. Scene-only and Region-only badges identify controls limited to one context. Hover or focus an info button to see what the parameter changes on the canvas. Select it to keep the card open. Each card also includes the default, range or choices, context, availability, API key, and control type.

30 exposed parameters1 Scene-onlysnow API type

iHover or focus an info button to see what the parameter changes on the canvas. Select it to keep the card open. Context badges identify Scene-only and Region-only controls; unbadged parameters are available in both. Hover or focus an availability condition to highlight the parameter that controls it.

Parameter	Control	Default	Range or choices	Availability
Below Tokensi belowTokens	checkbox	Off	—	Always
Below Tilesi belowTiles	checkbox	Off	—	Always
Below Foregroundi belowForeground	checkbox	Off	—	Always
Levelsi levelsScene only	scene-levels	All Levels	—	Always
Tinti tint	color	#FFFFFF (disabled)	—	Always
Sound FXi soundFxEnabled	checkbox	Off	—	Always
Sound FX Soundsi soundFxManualSoundIds	multi-select	Rule default	—	Shown when Sound FX = On and the matching enabled SoundFX rule uses Multi-Sound Mode = Manual with at least two configured sounds
Top Downi topDown	checkbox	Off	—	Always
Directioni direction	range	—	0–360 · step 5	Shown when Top Down = Off
Synchronized Directioni synchronizedDirection	checkbox	Off	—	Shown when Top Down = Off
Scalei scale	range	0.27	0.1–1 · step 0.01	Always
Speedi speed	range	0.14	0.1–1 · step 0.01	Always
Lifetimei lifetime	range	0.27	0.1–1 · step 0.01	Always
Densityi density	range	0.16	0.1–1 · step 0.01	Always
Opacityi alpha	range	1	0–1 · step 0.1	Always
Backgroundi backgroundEnabled	checkbox	Off	—	Always
Background Filli backgroundMode	select	accumulate	Full Coverage, Fill Over Time	Shown when Background = On
Time to Full Coveragei backgroundDuration	range	180	10–3600 · step 10	Shown when Background = On and Background Fill = Fill Over Time
Background Opacityi backgroundOpacity	range	0.7	0–1 · step 0.01	Shown when Background = On
Fill Variationi backgroundFillVariation	range	0.75	0–1 · step 0.05	Shown when Background = On and Background Fill = Fill Over Time
Drift Heighti backgroundDriftStrength	range	0.5	0–1 · step 0.05	Shown when Background = On
Drift Size (Grid Spaces)i backgroundDriftScale	range	0.07	0.01–1 · step 0.01	Shown when Background = On
Token Trailsi backgroundTrailsEnabled	checkbox	Off	—	Shown when Background = On
Refill Trails Over Timei backgroundTrailRefillEnabled	checkbox	On	—	Shown when Background = On and Token Trails = On
Trail Refill Timei backgroundTrailRefillDuration	range	90	10–3600 · step 10	Shown when Background = On and Token Trails = On and Refill Trails Over Time = On
Trail Widthi backgroundTrailWidth	range	0.5	0–2 · step 0.05	Shown when Background = On and Token Trails = On
Trail Strengthi backgroundTrailStrength	range	0.25	0–1 · step 0.01	Shown when Background = On and Token Trails = On
Token Elevation Thresholdi backgroundInteractionElevationThreshold	number-infinity	5	0–Infinity · step 0.5	Shown when Background = On and Token Trails = On
Darkness Activationi darknessActivationEnabled	checkbox	Off	—	Always
Darkness Activation Rangei darknessActivationRange	range-dual	{"min":0,"max":1}	0–1 · step 0.01	Shown when Darkness Activation = On

Direct-effect API example

The Direct Effect API creates a separate row shown through Manage API Effects. Add a stable apiMacro_…_p or apiMacro_…_f ID when later macro calls need to update or stop the same row.

const created = await FXMASTER.api.effects.play({
  particles: [{
    "id": "apiMacro_wikisnow_p",
    "type": "snow",
    "options": {
      "topDown": true,
      "direction": 270,
      "speed": 0.25,
      "density": 0.4,
      "backgroundEnabled": false
    }
  }],
});

await FXMASTER.api.effects.particles.stop(created.particles);

For complete API behavior, scene targeting, stack ordering, and toggle groups, see the Direct Effect API guide.