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PostRoll Help

Atmosphere and weather

Beyond ambient darkness and mood, PostRoll adds four atmosphere layers you can stack:

  • Atmospheric fog — animated drifting haze.
  • Weather — clear / overcast / rain / snow / storm / fog state machine that drives several subsystems together.
  • Volumetrics — god-rays / light-shaft effect.
  • Reflectivity — wet-floor mirrored reflection.

All of these are configured in the Scene Lighting panel.

Atmospheric fog

Section titled “Atmospheric fog”

A separate haze layer that drifts across the scene — useful for damp morning mist, smoky tavern, magical haze. Settings in the Atmospheric Fog section:

Field Effect
Enabled Master on/off.
Density 0..1 — how thick. 0.4 is a noticeable but pierceable haze; 0.95 is pea soup.
Color Tint of the haze (defaults to neutral grey).

Atmospheric fog drifts subtly on its own. It’s separate from fog of war (the explored / unexplored mask) — both can coexist.

Weather

Section titled “Weather”

Weather is a high-level state that drives several lighting subsystems together so you can pick “rain” once instead of tuning fog density + ambient tint + particles + lightning individually.

In the Weather section, the Type select offers:

Type What you get
Clear No overrides — your manual fog / ambient / mood show through unchanged.
Overcast Light pearly haze + a cool tint nudge on ambient.
Rain Cool grey haze + cool tint + falling rain particles.
Snow Heavy soft haze + snowfall particles + cool tint.
Storm Heavy dark haze + rain particles + periodic lightning strobe.
Fog Pea-soup atmospheric fog only (no particles, no tint).

The Intensity slider scales the effect strength. 1 is the recommended look; lower values dial down for a subtle hint.

Lightning

Section titled “Lightning”

Storm weather has periodic strobes — brief brightness flashes across the whole lighting layer. The mean gap between strikes is configurable (defaults to 7 seconds for storm; the actual gap jitters around it so strikes don’t feel mechanical).

Volumetrics (god-rays)

Section titled “Volumetrics (god-rays)”

Volumetric light shafts — the streaks you see when light filters through dust or fog. In the Volumetrics section:

Field Effect
Enabled Master on/off.
Intensity 0..1 — strength of the rays.
Decay 0..1 — how quickly the rays fade with distance.
Source What seeds the rays (see below).

The Source select decides where rays come from:

  • Lights — rays seed from your scene lights only. Token vision halos are excluded so you don’t get rays from every player’s flashlight.
  • Scene — rays seed from the basemap’s painted detail (works well with painted sun-disc / cathedral-window maps).
  • Both — blends scene + lights for the richest look.

Volumetrics are the most expensive single feature in the lighting stack. If your scene drops frames, this is the first thing to dial down.

Reflectivity (wet floor)

Section titled “Reflectivity (wet floor)”

The Reflectivity section adds a mirrored copy of the lighting composite below a “floor” line — perfect for rain-soaked streets, a flooded dungeon, an icy lake.

Field Effect
Enabled Master on/off.
Amount 0..1 — how strong the reflection is.
Floor Y Pixel Y coordinate of the reflection plane (the “ground line”).
Tint Colour the reflection through (cool blue for water, neutral for polished stone).

The reflection mirrors the lighting layer only — your map sprite stays as drawn. Pair with Storm weather and an inky tint for a noir noir noir look.

Putting it together

Section titled “Putting it together”

A few weather-driven set-pieces:

Scene Mood Weather Atm. fog Volumetrics Reflectivity
Foggy graveyard at dawn Moonlight Fog density 0.7, blue-grey Lights, low intensity off
Tavern fire scene Warm Tavern Clear density 0.2, warm off off
Storm-tossed deck Stormy Storm (driven by weather) off on, water tint
Cathedral with sunbeam Daylight Clear density 0.3, neutral Both, high intensity off

A note on performance

Section titled “A note on performance”

At the bottom of the Scene Lighting panel there’s a Performance section with one control today: Penumbra quality (off / low / medium / high). This is per-client — each device picks its own based on its GPU. PostRoll auto-detects mobile and low-core machines and starts you on low; everyone else defaults to medium. Override if you have a beefy GPU and want crisper soft shadows, or dial down if you’re seeing frame drops.

Volumetric god-rays are the single most expensive effect — if you’re squeezing frames, that’s the first thing to disable. Then atmospheric fog, then storm weather (rain particles + lightning).

Section titled “Related”