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Fog memory

By default, fog of war has two states: revealed (you’ve seen it, it’s fully visible) or unrevealed (you haven’t seen it, it’s black). When a token walks through a corridor and out the other side, the corridor stays fully revealed even though no light is currently shining on it.

But what about the opposite — when a token leaves a torch-lit room and the torch goes with them? In a strict-darkness scene, the fog stays cleared (the room is “explored”) but the room is now back to full ambient darkness — pitch black. The player saw the room once, but now sees nothing.

Fog memory fixes that. It keeps a dim impression of the explored areas even when they’re no longer being lit, so the player retains a low-contrast view of what they’ve seen.

Turning it on

Section titled “Turning it on”
  1. Open the Scene Lighting panel.
  2. Scroll to the Fog Memory section.
  3. Toggle Enabled on.
  4. Adjust the Brightness slider to taste.
Brightness What it looks like
0 Identical to the default — no memory; explored-but-unlit areas go fully dark.
0.25 Subtle — explored areas have a faint impression.
0.5 Moderate — clearly visible but obviously dim relative to lit areas.
1 Maximum — explored areas stay fully visible (lit or not).

When to use it

Section titled “When to use it”
Scene type Recommendation
Dungeon crawl Yes — fog memory at 0.2–0.4 is table-stakes for the genre.
Outdoor exploration Maybe — useful for moonlit / night scenes; redundant in daylight.
Tactical combat Optional — the dim memory of distant tokens may help or hinder depending on what your players are tracking.
Cinematic / set-piece Probably not — you usually want full control of what’s visible per beat.

How it works under the hood

Section titled “How it works under the hood”

Fog memory keeps a per-pixel record of the lighting at every spot a player has had vision over. When the players move on, the engine displays the brighter of two values per pixel:

  • the live lighting (when something currently illuminates the spot), or
  • the remembered lighting times your brightness setting (when nothing currently lights it).

So a torch that lit a corridor leaves the corridor dimly visible at brightness × original strength after the torch is gone. Unexplored areas — places the players have never had vision over — stay fully dark. There’s a clean boundary: explored = dim impression, unexplored = pitch black.

Toggling fog memory off wipes the accumulated state so re-enabling it later doesn’t surface stale memory from earlier in the session.

Disabling

Section titled “Disabling”

Toggle Enabled off in the Fog Memory section. The brightness floor returns to whatever your ambient darkness alone produces. The fog of war state itself doesn’t change — explored areas are still tracked the same way; they just go to full ambient darkness when no light is on them.

Section titled “Related”