FEAR stains the forbidden ground in the cockpit too

The aura's warp-walking diamond — dreadDistance ≤ 3, extracted to one
shared fearCells so the board's dashed ring, the cockpit's floor stain,
and the engine's refusal can never disagree — now tints the flagstones
violet in first person, breathing like the board's aura, beneath the
dread ring already at the bearer's feet.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015RCWSTnb1KYTPyL4GmhGnF

packages/engine/src/view.ts

@@ -16,6 +16,7 @@ import {
   type SustainedEffect,
   type TreasureState,
   type TurnState,
+  dreadDistance,
 } from "./game";
 
 export interface PlayerPublicView {
@@ -193,6 +194,22 @@ export function viewFor(state: GameState, playerId: PlayerId): GameView {
  * reflects what this player knows (illusion walls they believe in block it).
  * The basis for the client's "dim the ineligible squares" targeting aid.
  */
+/** Every square inside a living FEAR-bearer's aura — dreadDistance walks
+ * through warps, the engine's own yardstick, so the painted aura and the
+ * movement refusal can never disagree. */
+export function fearCells(view: GameView): Set<string> {
+  const out = new Set<string>();
+  for (const fp of view.players) {
+    if (!fp.alive) continue;
+    if (!view.sustained.some((e) => e.cardId === "fear" && e.targetId === fp.id)) continue;
+    for (const k of Object.keys(view.board.cells)) {
+      const [x, y] = k.split(",").map(Number) as [number, number];
+      if (dreadDistance(view.board, fp.position, { x, y }) <= 3) out.add(k);
+    }
+  }
+  return out;
+}
+
 export function sightedCellsFor(view: GameView): Set<string> {
   const out = new Set<string>();
   const me = view.players.find((p) => p.id === view.you);

packages/web/src/Board.svelte

@@ -2,7 +2,7 @@
   import type { Component } from "svelte";
   import type { GameView, SightTrace } from "@wizwar/engine";
   import type { Side } from "@wizwar/engine";
-  import { dreadDistance } from "@wizwar/engine";
+  import { fearCells } from "@wizwar/engine";
   import type { BoardFx } from "./fx";
   import { colorIndexOf as sharedColorIndex, wizardColor } from "./colors";
   import { CREATURE_ART, objectArt, TERRAIN_ART, tokenArt } from "./art";
@@ -212,18 +212,7 @@
   // ("even if walls separate you"), never diagonally — and the maze wraps,
   // so the diamond continues from the opposite rim. The engine's own
   // yardstick, so the aura and the refusal can never disagree.
-  const fearCells = $derived.by(() => {
+  const fearAura = $derived(fearCells(view));
-    const out = new Set<string>();
-    for (const fp of view.players) {
-      if (!fp.alive) continue;
-      if (!view.sustained.some((e) => e.cardId === "fear" && e.targetId === fp.id)) continue;
-      for (const k of Object.keys(view.board.cells)) {
-        const [x, y] = k.split(",").map(Number) as [number, number];
-        if (dreadDistance(view.board, fp.position, { x, y }) <= 3) out.add(k);
-      }
-    }
-    return out;
-  });
 
   // Warp pairs share a letter, like the printed openings on the real boards.
   const warpLetters = $derived.by(() => {
@@ -692,7 +681,7 @@
     {/each}
   {/if}
   <!-- FEAR's bubble: the three-space diamond, through walls, wrapping the rim -->
-  {#each fearCells as key (key)}
+  {#each fearAura as key (key)}
     {@const bx = Number(key.split(",")[0])}
     {@const by = Number(key.split(",")[1])}
     <rect x={bx * CELL + 1.5} y={by * CELL + 1.5} width={CELL - 3} height={CELL - 3}

packages/web/src/fpv/FirstPerson.svelte

@@ -9,6 +9,7 @@
   import { terrainFallback, TERRAIN3D } from "./terrain3d";
   import { tokenArt } from "../art";
   import { PLAYER_COLORS } from "../colors";
+  import { fearCells } from "@wizwar/engine";
 import type { GameView } from "@wizwar/engine";
 
   let {
@@ -120,6 +121,23 @@
     }
     return px;
   }
+  // The dread-stained squares, rasterized once per view (null = no fear).
+  const dreadCache = new WeakMap<object, Uint8Array | null>();
+  function dreadGridOf(v: GameView): Uint8Array | null {
+    if (dreadCache.has(v)) return dreadCache.get(v)!;
+    const cells = fearCells(v);
+    let grid: Uint8Array | null = null;
+    if (cells.size > 0) {
+      grid = new Uint8Array(v.board.width * v.board.height);
+      for (const k of cells) {
+        const [fx, fy] = k.split(",").map(Number) as [number, number];
+        if (fx >= 0 && fy >= 0 && fx < v.board.width && fy < v.board.height) grid[fy * v.board.width + fx] = 1;
+      }
+    }
+    dreadCache.set(v, grid);
+    return grid;
+  }
+
   let frame: ImageData | null = null;
 
   // The floor wears decals: home emblems in their owners' colors, pits
@@ -222,6 +240,10 @@
         if (lx >= 0 && ly >= 0 && lx < litBw && ly < litBh) litGrid[ly * litBw + lx] = 1;
       }
     }
+    // FEAR's aura stains the forbidden ground itself, as the board draws
+    // its dashed diamond — the same warp-walking yardstick behind both.
+    const dreadGrid = dreadGridOf(view);
+    const dreadBlend = dreadGrid ? 0.16 + 0.07 * Math.sin(time / 400) : 0;
     for (let row = 0; row < H; row++) {
       const below = row > half;
       const dz = below ? row - half : half - row;
@@ -260,6 +282,14 @@
             const gx = (wx - u) | 0, gy = (wy - v) | 0;
             if (gx < 0 || gy < 0 || gx >= litBw || gy >= litBh || !litGrid[gy * litBw + gx]) sh *= 0.3;
           }
+          if (dreadGrid && below) {
+            const gx = (wx - u) | 0, gy = (wy - v) | 0;
+            if (gx >= 0 && gy >= 0 && gx < litBw && gy < litBh && dreadGrid[gy * litBw + gx]) {
+              r = r * (1 - dreadBlend) + 122 * dreadBlend;
+              g = g * (1 - dreadBlend) + 74 * dreadBlend;
+              b = b * (1 - dreadBlend) + 138 * dreadBlend;
+            }
+          }
           if (dec) {
             const hx = (wx - u) | 0, hy = (wy - v) | 0;
             if (hx >= 0 && hy >= 0 && hx < dec.bw && hy < dec.bh) {