Add hidden fossils: persistent meta-collectibles

src/audio.ts

@@ -307,6 +307,13 @@ export class AudioManager {
         this.tone({ freq: 340, to: 130, dur: 0.16, type: 'sawtooth', vol: 0.14 });
         this.noiseBurst({ dur: 0.08, vol: 0.08, freq: 700 });
         break;
+      case 'fossil': {
+        // Deep unearth thud followed by a warm two-note chime.
+        this.noiseBurst({ dur: 0.1, vol: 0.14, freq: 420 });
+        this.tone({ freq: 392, dur: 0.14, type: 'triangle', vol: 0.2, delay: 0.04 });
+        this.tone({ freq: 587, dur: 0.2, type: 'sine', vol: 0.18, delay: 0.14 });
+        break;
+      }
       case 'cheat':
         [784, 988, 1175, 1568].forEach((f, i) =>
           this.tone({ freq: f, dur: 0.09, type: 'sine', vol: 0.16, delay: i * 0.05 }),

src/config.ts

@@ -34,6 +34,8 @@ export const CFG = {
     heartBonus: 400,
     /** Points a healing heart is worth when collected at full health. */
     heartFull: 200,
+    /** Points a hidden fossil is worth (re-collectable each run). */
+    fossil: 150,
     timeBonusBase: 2400,
     timeBonusPerSec: 10,
   },

src/ctx.ts

@@ -51,4 +51,9 @@ export interface GameCtx {
    * the player is already at full health.
    */
   collectHeart(x: number, y: number): void;
+  /**
+   * A hidden fossil was unearthed: score + sparkle, and the first discovery
+   * is persisted to the fossil codex (id = "<levelIdx>:<i>").
+   */
+  collectFossil(x: number, y: number, id: string): void;
 }

src/fossil.ts

@@ -0,0 +1,82 @@
+import { TAU } from './config';
+
+/**
+ * A hidden fossil: a persistent meta-collectible. Found once (stored across
+ * runs by id "<levelIdx>:<i>"), but re-collectable for score on later runs.
+ */
+export class Fossil {
+  x: number;
+  y: number;
+  w = 28;
+  h = 20;
+  id: string;
+  collected = false;
+  phase = Math.random() * TAU;
+
+  constructor(x: number, y: number, id: string) {
+    this.x = x;
+    this.y = y;
+    this.id = id;
+  }
+
+  get rect(): { x: number; y: number; w: number; h: number } {
+    return { x: this.x - 15, y: this.y - 13, w: 30, h: 26 };
+  }
+
+  draw(ctx: CanvasRenderingContext2D, t: number): void {
+    const bob = Math.sin(t * 1.8 + this.phase) * 2.5; // heavy — bobs less than crystals
+    const cx = this.x;
+    const cy = this.y + bob;
+    const pulse = 0.5 + 0.5 * Math.sin(t * 2.2 + this.phase);
+    ctx.save();
+    ctx.translate(cx, cy);
+    // warm unearthed glow
+    ctx.globalAlpha = 0.22 + 0.16 * pulse;
+    ctx.fillStyle = '#e8dcc0';
+    ctx.beginPath();
+    ctx.arc(0, 0, 17 + 2 * pulse, 0, TAU);
+    ctx.fill();
+    ctx.globalAlpha = 1;
+    // bone shaft
+    const grad = ctx.createLinearGradient(0, -5, 0, 5);
+    grad.addColorStop(0, '#f4ecd9');
+    grad.addColorStop(1, '#cbb98f');
+    ctx.fillStyle = grad;
+    ctx.fillRect(-10, -3.5, 20, 7);
+    // knob ends (two circles per side)
+    for (const sx of [-1, 1]) {
+      for (const sy of [-3.2, 3.2]) {
+        ctx.beginPath();
+        ctx.arc(sx * 11, sy, 4, 0, TAU);
+        ctx.fill();
+      }
+    }
+    // weathering crack
+    ctx.strokeStyle = 'rgba(110,90,55,0.55)';
+    ctx.lineWidth = 1.2;
+    ctx.beginPath();
+    ctx.moveTo(-4, -3);
+    ctx.lineTo(-1, 0);
+    ctx.lineTo(-4, 3);
+    ctx.stroke();
+    // outline
+    ctx.strokeStyle = 'rgba(110,90,55,0.4)';
+    ctx.lineWidth = 1;
+    ctx.strokeRect(-10, -3.5, 20, 7);
+    ctx.restore();
+    // sparkle
+    if (Math.sin(t * 1.9 + this.phase * 3) > 0.88) {
+      ctx.save();
+      ctx.translate(cx + 10, cy - 11);
+      ctx.strokeStyle = '#fff';
+      ctx.lineWidth = 1.3;
+      ctx.beginPath();
+      ctx.moveTo(-3.5, 0);
+      ctx.lineTo(3.5, 0);
+      ctx.moveTo(0, -3.5);
+      ctx.lineTo(0, 3.5);
+      ctx.stroke();
+      ctx.restore();
+    }
+  }
+}

src/game.ts

@@ -1,7 +1,7 @@
 import { CFG, VW, VH, TAU, FONT_STACK, DIFFICULTIES, STARS } from './config';
 import type { Difficulty } from './config';
 import { clamp, easeOutBack, fmtTime } from './util';
-import { Store, getStats, getBest, getBestStars, getDailyBest, getDailyStars, getGhostEnabled, setGhostEnabled, getGhostTrack, saveGhostTrack } from './store';
+import { Store, getStats, getBest, getBestStars, getDailyBest, getDailyStars, getGhostEnabled, setGhostEnabled, getGhostTrack, saveGhostTrack, getFoundFossils, findFossil } from './store';
 import type { GameStats } from './store';
 import { AudioManager } from './audio';
 import { Input } from './input';
@@ -122,6 +122,8 @@ export class Game implements GameCtx {
   rainbow = false;
   /** Ghost race: replay the stored best run alongside the player. */
   ghostOn: boolean = getGhostEnabled();
+  /** Fossil ids discovered so far (persistent meta-progress). */
+  fossilsFound: string[] = getFoundFossils();
   private ghost: GhostPlayer | null = null;
   private ghostRec: GhostRecorder | null = null;
   /** Cheat queue: apply max hearts once a player exists. */
@@ -260,10 +262,16 @@ export class Game implements GameCtx {
   /* ---------- lifecycle ---------- */
   buildLevel(): void {
     const info = this.currentInfo();
-    this.level = new Level(info.def, this, DIFFICULTIES[this.difficulty].enemySpeed);
+    // Daily levels have no fossils; the sentinel keeps fossil ids stable.
+    this.level = new Level(info.def, this, DIFFICULTIES[this.difficulty].enemySpeed, this.daily ? -1 : this.levelIdx);
     this.bg.theme = info.theme;
   }
 
+  /** Total hidden fossils across the hand-built levels. */
+  totalFossils(): number {
+    return LEVELS.reduce((n, l) => n + (l.def.fossils?.length ?? 0), 0);
+  }
+
   startGame(): void {
     this.buildLevel();
     this.player = new Player(this.level!.start.x, this.level!.start.y, this);
@@ -524,6 +532,25 @@ export class Game implements GameCtx {
     }
   }
 
+  /** Fossil pickup (GameCtx): persistent discovery + re-collectable score. */
+  collectFossil(x: number, y: number, id: string): void {
+    const first = !this.fossilsFound.includes(id);
+    if (first) {
+      findFossil(id);
+      this.fossilsFound = getFoundFossils();
+    }
+    this.addScore(CFG.score.fossil, x, y - 14);
+    this.audio.play('fossil');
+    if (first) {
+      this.addStatus('Fossil found! ' + this.fossilsFound.length + '/' + this.totalFossils(), '#e8dcc0');
+      this.addShake(2);
+      this.burst(x, y, 22, ['#f4ecd9', '#e8dcc0', '#cbb98f', '#fff'], 'dot', 170);
+      this.texts.push(new FloatingText(x, y - 34, 'NEW FOSSIL!', '#f4ecd9'));
+    } else {
+      this.burst(x, y, 10, ['#f4ecd9', '#e8dcc0'], 'dot', 130);
+    }
+  }
+
   burst(x: number, y: number, n: number, colors: string[], type: ParticleType, speed: number): void {
     if (this.reducedMotion) n = Math.max(1, Math.floor(n * 0.4));
     for (let i = 0; i < n; i++) {
@@ -753,6 +780,9 @@ export class Game implements GameCtx {
     for (const h of this.level!.hearts) {
       if (!h.collected) h.draw(ctx, this.time);
     }
+    for (const f of this.level!.fossils) {
+      if (!f.collected) f.draw(ctx, this.time);
+    }
     for (const e of this.level!.enemies) {
       if (e.dead) continue;
       if (e.x + e.w < camX - 60 || e.x > camX + VW + 60) continue;
@@ -1048,17 +1078,34 @@ export class Game implements GameCtx {
     ctx.font = '800 17px ' + FONT_STACK;
     ctx.textAlign = 'left';
     ctx.fillText('× ' + (this.crystalsGot || 0) + '/' + (this.level ? this.level.totalCrystals : 0), cx + 14, 38);
-    // Score & time (right)
+    // Score, time & fossil count (right)
     ctx.textAlign = 'right';
     ctx.fillStyle = 'rgba(20,30,45,0.55)';
-    this.roundRect(ctx, VW - 190, 10, 180, 62, 12);
+    this.roundRect(ctx, VW - 190, 10, 180, 84, 12);
     ctx.fill();
     ctx.fillStyle = '#ffe28a';
     ctx.font = '800 19px ' + FONT_STACK;
     ctx.fillText('Score ' + this.score, VW - 24, 34);
     ctx.fillStyle = '#cfe8ff';
     ctx.font = '700 15px ' + FONT_STACK;
-    ctx.fillText('Time ' + fmtTime(this.elapsed), VW - 24, 58);
+    ctx.fillText('Time ' + fmtTime(this.elapsed), VW - 24, 56);
+    // Fossil meta-progress with a tiny bone glyph
+    ctx.font = '700 13px ' + FONT_STACK;
+    const fossilTxt = 'Fossils ' + this.fossilsFound.length + '/' + this.totalFossils();
+    const fossilW = ctx.measureText(fossilTxt).width;
+    ctx.fillText(fossilTxt, VW - 24, 80);
+    ctx.save();
+    ctx.translate(VW - 24 - fossilW - 16, 75);
+    ctx.fillStyle = '#e8dcc0';
+    ctx.fillRect(-6, -1.8, 12, 3.6);
+    for (const kx of [-7, 7]) {
+      for (const ky of [-2.2, 2.2]) {
+        ctx.beginPath();
+        ctx.arc(kx, ky, 2.2, 0, TAU);
+        ctx.fill();
+      }
+    }
+    ctx.restore();
     // Progress toward the nest (top centre, between the panels)
     if (this.player && this.level) this.drawProgress(ctx);
     // Combo chip while a crystal chain is alive
@@ -1495,7 +1542,7 @@ export class Game implements GameCtx {
     ctx.font = '600 12px ' + FONT_STACK;
     ctx.fillStyle = 'rgba(255,255,255,0.6)';
     ctx.fillText(
-      'PLAYS ' + this.stats.runs + '  ·  DEATHS ' + this.stats.deaths + '  ·  CRYSTALS ' + this.stats.crystals + '  ·  HEARTS ' + this.stats.hearts + '  ·  SINCE ' + since,
+      'PLAYS ' + this.stats.runs + '  ·  DEATHS ' + this.stats.deaths + '  ·  CRYSTALS ' + this.stats.crystals + '  ·  HEARTS ' + this.stats.hearts + '  ·  FOSSILS ' + this.fossilsFound.length + '/' + this.totalFossils() + '  ·  SINCE ' + since,
       VW / 2,
       205,
     );
@@ -1532,6 +1579,7 @@ export class Game implements GameCtx {
       'Stomp beetles, trikes & pteros',
       'Watch for lava, spikes & rocks',
       'Touch flags to save progress',
+      'Unearth the hidden fossils',
     ];
     ctx.font = '600 13px ' + FONT_STACK;
     quest.forEach((r, i) => {
@@ -1582,13 +1630,30 @@ export class Game implements GameCtx {
           ctx.stroke();
         }
       }
+      // Fossil dots (hand-built levels only: one per hidden fossil)
+      if (!isDaily) {
+        const fCount = LEVELS[i].def.fossils?.length ?? 0;
+        for (let f = 0; f < fCount; f++) {
+          const found = this.fossilsFound.includes(i + ':' + f);
+          const fx = cx0 + cw / 2 + (f - (fCount - 1) / 2) * 18;
+          ctx.fillStyle = found ? '#f4ecd9' : 'rgba(255,255,255,0.16)';
+          ctx.fillRect(fx - 5, cardY + 82, 10, 2.6);
+          for (const kx of [-5, 5]) {
+            for (const ky of [-2.4, 2.4]) {
+              ctx.beginPath();
+              ctx.arc(fx + kx, cardY + 83.3 + ky, 2.4, 0, TAU);
+              ctx.fill();
+            }
+          }
+        }
+      }
       // Records
       const bb = isDaily ? getDailyBest() : getBest(i);
       ctx.font = '600 12px ' + FONT_STACK;
       ctx.textAlign = 'center';
       ctx.fillStyle = 'rgba(220,232,245,0.85)';
-      ctx.fillText('Score ' + (bb.score || '—'), cx0 + cw / 2, cardY + 98);
-      ctx.fillText('Time ' + (bb.time === null ? '—' : fmtTime(bb.time)), cx0 + cw / 2, cardY + 118);
+      ctx.fillText('Score ' + (bb.score || '—'), cx0 + cw / 2, cardY + 104);
+      ctx.fillText('Time ' + (bb.time === null ? '—' : fmtTime(bb.time)), cx0 + cw / 2, cardY + 122);
       ctx.font = '600 11px ' + FONT_STACK;
       ctx.fillStyle = 'rgba(255,255,255,0.45)';
       ctx.fillText(isDaily ? dailyLabel(dailySeed()) : 'TAP · ←/→', cx0 + cw / 2, cardY + 138);

src/level-data.ts

@@ -70,6 +70,8 @@ export interface LevelDef {
   decor: DecorDef[];
   /** Spring pads: {x, groundTopY}. Launch the player upward. */
   springs?: Point[];
+  /** Hidden fossils: persistent meta-collectibles (id = "<levelIdx>:<i>"). */
+  fossils?: Point[];
   /** Pressure plates: hold to keep the referenced door (index into `doors`) open. */
   plates?: { x: number; y: number; door: number }[];
   /** Sliding gates: {x, y, w, h}; y is the top, bottom meets the ground. */
@@ -199,6 +201,11 @@ const LEVEL_1: LevelDef = {
     { x: 2660, y: 330 }, // stone ledge before the spikes
     { x: 5080, y: 428 }, // just past the spike gauntlet
   ],
+  fossils: [
+    { x: 3255, y: 163 }, // high bonus route — top of the jump chain
+    { x: 3230, y: 363 }, // stepping stone over lava pool A
+    { x: 4990, y: 323 }, // stone ledge right above the spike pit
+  ],
   goal: { x: 7150, y: 460 },
   decor: [
     { type: 'sign', x: 120 },
@@ -321,6 +328,11 @@ const LEVEL_2: LevelDef = {
     { x: 4300, y: 428 }, // safe ground after the lava moat
     { x: 6340, y: 332 }, // stone ledge above the rock gauntlet
   ],
+  fossils: [
+    { x: 2830, y: 393 }, // stepping stone mid-moat, lava on both sides
+    { x: 5685, y: 313 }, // stone above the twin falling-rock gauntlet
+    { x: 7010, y: 275 }, // high stone of the home-stretch jump chain
+  ],
   goal: { x: 7350, y: 460 },
   decor: [
     { type: 'sign', x: 120 },
@@ -447,6 +459,11 @@ const LEVEL_3: LevelDef = {
     { x: 3720, y: 428 }, // just past the first gate
     { x: 7720, y: 428 }, // past the final gate, near the goal
   ],
+  fossils: [
+    { x: 3860, y: 425 }, // just behind the first gate
+    { x: 5925, y: 263 }, // bonus spring ledge, high above the rockfall ridge
+    { x: 7700, y: 425 }, // behind the final gate, patrolled by a beetle
+  ],
   goal: { x: 7850, y: 460 },
   decor: [
     { type: 'sign', x: 120 },

src/level.ts

@@ -13,6 +13,7 @@ import { SpringPad } from './spring';
 import { PressurePlate } from './plate';
 import { Door } from './door';
 import { Projectile } from './projectile';
+import { Fossil } from './fossil';
 
 export class Level {
   width: number;
@@ -33,12 +34,14 @@ export class Level {
   plates: PressurePlate[];
   doors: Door[];
   projectiles: Projectile[];
+  fossils: Fossil[];
   readonly game: GameCtx;
 
-  constructor(d: LevelDef, game: GameCtx, enemySpeed = 1) {
+  constructor(d: LevelDef, game: GameCtx, enemySpeed = 1, levelIdx = 0) {
     this.width = d.width;
     this.enemySpeed = enemySpeed;
     this.game = game;
+    this.fossils = (d.fossils ?? []).map((f, i) => new Fossil(f.x, f.y, levelIdx + ':' + i));
     this.springs = (d.springs ?? []).map((s) => new SpringPad(s.x, s.y));
     this.plates = (d.plates ?? []).map((p) => new PressurePlate(p.x, p.y, game));
     this.doors = (d.doors ?? []).map((dr) => new Door(dr.x, dr.y, dr.w, dr.h, game));
@@ -114,6 +117,7 @@ export class Level {
     this.projectiles = [];
     for (const c of this.crystals) c.collected = false;
     for (const h of this.hearts) h.collected = false;
+    for (const f of this.fossils) f.collected = false;
     for (const e of this.enemies) e.reset();
     // Restore each hazard's own interval (the original hard-coded 2.2,
     // clobbering hazards configured with a different one).

src/player.ts

@@ -310,6 +310,15 @@ export class Player {
       }
     }
 
+    // --- Fossils (persistent discoveries, re-collectable for score) ---
+    for (const f of level.fossils) {
+      if (f.collected) continue;
+      if (overlap(this.rect, f.rect)) {
+        f.collected = true;
+        this.game.collectFossil(f.x, f.y, f.id);
+      }
+    }
+
     // --- Enemies: stomp from above, hurt from the side ---
     for (const e of level.enemies) {
       if (e.dead) continue;

src/store.ts

@@ -75,6 +75,23 @@ export function saveGhostTrack(idx: number, track: GhostTrack): void {
   Store.set(key, track);
 }
 
+/**
+ * Found fossil ids ("<levelIdx>:<i>"), persistent across runs. A fossil can
+ * be re-collected for score on later runs, but only the first discovery
+ * counts toward the codex.
+ */
+export function getFoundFossils(): string[] {
+  const v = Store.get<string[] | null>('tinyrex_fossils', null);
+  return Array.isArray(v) ? v : [];
+}
+
+/** Record a fossil discovery; no-op when it is already in the codex. */
+export function findFossil(id: string): void {
+  const found = getFoundFossils();
+  if (found.includes(id)) return;
+  Store.set('tinyrex_fossils', [...found, id]);
+}
+
 /** Safe localStorage wrapper (settings + best records). */
 export const Store = {
   get<T>(key: string, fallback: T): T {