Sound: recorded SFX layer + a touch-easier CPU

Wire the new assets/audio/*.wav samples over the synth SFX:
- Ball hits: per-side tennis-player / tennis-opponent on serve & return,
  now with a stadium reverb tail (same convolver as umpire/aww).
- Crowd: tennis-applaus on your points/games (louder on big moments);
  tennis-aww when the opponent scores or you're eaten (reverb tail).
- Ambient bed: tennis-ambient-loop from first tap, 500Hz lowcut, low vol.
- Zombie music: zombie-mode loop when splatter kicks in (800Hz lowcut),
  fades out for the 1:1 sudden-death duel and back in after.
- Headshots: random headshot-1/-2 on every zombie kill (killZombie).

audio.js: sfx() one-shot player w/ rate+reverb opts, loopBed() beds with
duck/fade, aww() wrapper, hotter reverb send on the umpire voice.

Also: normal opponent aiFlub 0.09 -> 0.14 (a little easier to beat).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

audio.js

@@ -29,7 +29,9 @@ export function voice(name, delay = 0, rate = 1) {
   const play = buf => {
     const src = ac.createBufferSource(); src.buffer = buf;
     src.playbackRate.value = rate; // < 1 = slower and lower — the umpire's dark register
-    src.connect(ac.destination); src.connect(reverb(ac)); // dry + center-court echo
+    src.connect(ac.destination); // dry
+    const send = ac.createGain(); send.gain.value = 1.8; // umpire rides a wetter PA tail than the crowd sfx
+    src.connect(send).connect(reverb(ac)); // extra reverb send — the big-stadium announcer echo
     src.start(ac.currentTime + delay);
   };
   if (VOICE[name]) return play(VOICE[name]);
@@ -40,6 +42,62 @@ export function voice(name, delay = 0, rate = 1) {
     .catch(() => say(name.replace(/_/g, ' '), delay));
 }
 
+// Recorded one-shot SFX (assets/audio/tennis-*.wav): ball hits, applause, the crowd's aww.
+// Same load-once-then-cache pattern as voice(), but dry (no PA reverb) and with a volume knob.
+const SFX = {};
+export function sfx(name, vol = 1, opts = {}) {
+  const ac = audio();
+  const play = buf => {
+    const src = ac.createBufferSource(); src.buffer = buf;
+    if (opts.rate) src.playbackRate.value = opts.rate; // < 1 stretches it a touch longer (and lower)
+    const g = ac.createGain(); g.gain.value = vol;
+    src.connect(g).connect(ac.destination);
+    if (opts.reverb) g.connect(reverb(ac)); // wet stadium tail on top of the dry sample
+    src.start();
+  };
+  if (SFX[name]) return play(SFX[name]);
+  fetch('assets/audio/' + name + '.wav')
+    .then(r => { if (!r.ok) throw 0; return r.arrayBuffer(); })
+    .then(ab => ac.decodeAudioData(ab))
+    .then(buf => { SFX[name] = buf; play(buf); })
+    .catch(() => {}); // missing sample = silence, never a thrown error mid-rally
+}
+
+// the crowd's groan — stretched a touch and pushed through the PA reverb for a longer, wetter sigh
+export function aww(vol = 1) { sfx('tennis-aww', vol * 0.5, { reverb: true }); }
+
+// Looping background beds (scene atmosphere, mode music): each starts once, highpass 'lowcut' + quiet gain.
+const beds = new Map(); // file -> {ac, g, vol} once playing (null while loading); see fadeBed
+function loopBed(file, lowcut, vol) {
+  if (beds.has(file)) return;
+  beds.set(file, null);
+  const ac = audio();
+  fetch('assets/audio/' + file + '.wav')
+    .then(r => { if (!r.ok) throw 0; return r.arrayBuffer(); })
+    .then(ab => ac.decodeAudioData(ab))
+    .then(buf => {
+      const src = ac.createBufferSource(); src.buffer = buf; src.loop = true;
+      const hp = ac.createBiquadFilter(); hp.type = 'highpass'; hp.frequency.value = lowcut;
+      const g = ac.createGain(); g.gain.value = vol;
+      src.connect(hp).connect(g).connect(ac.destination); src.start();
+      beds.set(file, { ac, g, vol });
+    })
+    .catch(() => beds.delete(file)); // failed start (decode/network) can retry next call
+}
+export const ambient = () => loopBed('tennis-ambient-loop', 500, 0.035);  // whole-scene atmosphere, from first tap
+export const zombieMusic = () => loopBed('zombie-mode', 800, 0.2);         // background music once splatter kicks in
+
+// duck a bed to silence (out=true) or back to its base level over `secs` — the sudden-death duel mutes the music
+function fadeBed(file, out, secs = 0.7) {
+  const b = beds.get(file);
+  if (!b) return;
+  const t = b.ac.currentTime;
+  b.g.gain.cancelScheduledValues(t);
+  b.g.gain.setValueAtTime(b.g.gain.value, t); // anchor at current level so a mid-fade toggle stays smooth
+  b.g.gain.linearRampToValueAtTime(out ? 0 : b.vol, t + secs);
+}
+export const zombieDuck = out => fadeBed('zombie-mode', out);
+
 let sysVoice = null;
 export function say(text, delay = 0) { // fallback when a recorded umpire line is missing
   try {

config.js

@@ -14,7 +14,7 @@ export const TUNE = {
   serveSpeed: 21, serveQualitySpeed: 7,
   aimError: 2.4,           // m of scatter at quality 0
   perfectMs: 45,           // |offset from window center| for PERFECT
-  aiQualityMin: 0.45, aiQualityMax: 0.85, aiFlub: 0.09,
+  aiQualityMin: 0.45, aiQualityMax: 0.85, aiFlub: 0.14, // ~86% of returns land (was 0.09) — a touch easier to beat
   aiReaction: 0.45,        // s before the CPU reads your shot — well-aimed corners are winners
   autoAssist: matchMedia('(pointer: coarse)').matches ? 1.15 : 0, // auto-run speed factor (mobile)
   zSpeed: 0.7,      // zombie shamble speed m/s

gameplay.js

@@ -2,7 +2,7 @@
 
 import { TUNE, COURT, CONTACT, VOLLEY, ZONE_DEPTH, HOME, P_BOUNDS, TOSS, SHOT_DEPTH, POSE_TIME, BOUNCE_IDLE } from './config.js';
 import { P, O, ball, score, crowd, G, other, deuceSide, setupPoint, sendBoy } from './state.js';
-import { audio, pock, swish, applause, voice } from './audio.js';
+import { audio, pock, swish, applause, voice, sfx, aww, zombieMusic, zombieDuck } from './audio.js';
 import { axisX, axisZ, takeFlickAim, touchPX } from './input.js';
 import { W } from './render.js'; // runtime-only cycle (render imports gameplay), same pattern as input/zombies
 import { updateZombies, spawnZombie, spawnRacketZombie, sweepCourt, zombies, explode, meleeSwipe, extras, parts } from './zombies.js';
@@ -106,7 +106,7 @@ function doHit(ch, quality, aim) {
     G.outMarker = { x: tx, z: tz, out: !ok, t: 1.3 };
     G.aiReactT = 0; // CPU hasn't read the shot yet
   }
-  pock(0.9, 950);
+  sfx(ch.side === 'P' ? 'tennis-player' : 'tennis-opponent', 0.9, { reverb: true }); // recorded racket strike, per side
   if (quality > 0.999) { G.hitstop = 0.05; G.flash = { text: 'PERFECT', t: 0.7 }; pock(0.5, 1600); }
   ch.pose = 'swing'; ch.poseT = 0;
 }
@@ -162,7 +162,7 @@ function hitServe(sv, quality, aim = null) {
     }
   }
   if (sv.side === 'P') G.outMarker = { x: boxX, z: tzs, out: G.mode === 'tennis' && !inServeBox(boxX, tzs), t: 1.3 };
-  G.phase = 'rally'; pock(1, 1100);
+  G.phase = 'rally'; sfx(sv.side === 'P' ? 'tennis-player' : 'tennis-opponent', 0.9, { reverb: true }); // recorded serve strike, per side
   sv.pose = 'serve'; sv.poseT = 0;
   if (quality > 0.999) { G.flash = { text: 'PERFECT', t: 0.7 }; G.hitstop = 0.05; }
 }
@@ -180,7 +180,7 @@ function scoreKey() {
 }
 
 export function cheer(seconds, vol) {
-  applause(seconds, vol);
+  sfx('tennis-applaus', Math.min(1.5, vol * 2.2)); // recorded crowd; vol scales with the size of the moment (gain > 1 amplifies)
   crowd.cheer = Math.max(crowd.cheer, seconds);
 }
 
@@ -203,6 +203,7 @@ function pointTo(side, reason) {
   const gameOver = advancePoint(side);
   G.phase = 'over'; G.overT = gameOver ? 3.2 : 2.2;
   sendBoy();
+  if (side === 'O') aww(0.8); // you dropped the point — the crowd sighs
   if (reason) voice(reason);
   if (gameOver) {
     if (G.mode === 'tennis' && side === 'P' && !G.everTransitioned) return startTransition();
@@ -232,7 +233,7 @@ export function splatPoint(side, quiet = false) {
         (G.runGames > TUNE.ballChangeFirst && (G.runGames - TUNE.ballChangeFirst) % TUNE.ballChangeEvery === 0))
       G.tinDue = true;
     voice(side === 'P' ? 'game_set_massacre' : 'game_opponent', 0.5); // game-win lines always speak
-    cheer(2.2, 0.5);
+    if (side === 'P') cheer(2.2, 0.5); else aww(0.85); // your game = applause, theirs = a groan
     sweepCourt();          // the wave is OVER: survivors collapse where they stand — a game ends visibly
     ball.active = false;   // the beat owns the court
     G.pendingGame = true;  // 'GAME N' announces the next wave when play resumes
@@ -282,12 +283,13 @@ function deliverTin() {
 export function resolveInterlude(side) {
   if (!G.interlude) return;
   G.interlude = false;
+  zombieDuck(false); // duel over — bring the music back up
   ball.active = false; G.phase = 'over'; G.overT = 2.2;
   if (side === 'P') {
     cheer(3, 0.7);
     deliverTin(); // win the point, win the next tin — on the spot
   } else {
-    voice('game_opponent', 0.4);
+    voice('game_opponent', 0.4); aww(0.85); // lost the sudden-death duel
     score.games[1]++; G.runGames++; G.shameGame = true; // it goes on the scoreboard
     if (score.games[1] >= 6) { G.sets[1]++; score.games = [0, 0]; }
     G.flash = { text: 'GAME. THEM.', t: 1.6 };
@@ -339,7 +341,7 @@ function transition(dt) {
   once('turn', 3.4, () => { spawnZombie(O.x, O.z, 'c'); G.hideO = true; }); // the opponent... turns
   once('mob', 4.8, () => { spawnZombie(-3.5, -1.6, 'a'); spawnZombie(2.5, -2.1, 'b'); });
   once('seated', 5.4, () => voice('remain_seated', 0, 0.95));
-  once('go', 8.2, () => { G.mode = 'splatter'; score.server = 'P'; setupPoint(); voice('play', 0.4, 0.9); });
+  once('go', 8.2, () => { G.mode = 'splatter'; score.server = 'P'; setupPoint(); voice('play', 0.4, 0.9); zombieMusic(); });
 }
 
 function fault() {
@@ -653,6 +655,7 @@ export function update(dt) {
       && G.phase === 'pretoss' && zombies.length === 1 && zombies[0].variant === 'r' && !zombies[0].dueled) {
     zombies[0].dueled = true; // one duel per opponent — after that it just rallies
     G.interlude = { introT: 2.4 }; // the intro beat: serving blocked, centered card, colors return
+    zombieDuck(true); // fade the zombie music out for the 1:1 duel
     voice('play_resume', 0.2); voice('sudden_death', 2.4);
   }
   if (G.interlude && G.interlude.introT > 0) G.interlude.introT -= dt;

main.js

@@ -7,7 +7,7 @@ import { TUNE, COURT, UMP_H, UMP_X } from './config.js';
 import { P, O, ball, score, G, setupPoint } from './state.js';
 import { update, keyPressed, solveShot, inServeBox, inCourt, forceZombies, splatPoint } from './gameplay.js';
 import { fitViewport, render, proj, RES } from './render.js';
-import { voice } from './audio.js';
+import { voice, ambient } from './audio.js';
 import { zombies, spawnZombie, piles, gore, parts, pellets, extras, explode } from './zombies.js';
 import { cv } from './dom.js';
 import './input.js';
@@ -27,7 +27,7 @@ setupPoint();
 const intro = document.getElementById('intro');
 function dismissIntro() {
   if (!intro.parentNode) return;
-  intro.remove(); voice('quiet_please');
+  intro.remove(); ambient(); voice('quiet_please'); // low atmosphere bed starts with the first gesture
 }
 intro.addEventListener('pointerdown', e => { e.preventDefault(); dismissIntro(); });
 addEventListener('keydown', () => dismissIntro(), { once: true });

zombies.js

@@ -5,7 +5,7 @@
 
 import { TUNE, COURT } from './config.js';
 import { G, P, ball, sendBoy, setupPoint } from './state.js';
-import { splat, moan, pock, voice, boom, swish, shriek } from './audio.js';
+import { splat, moan, pock, voice, boom, swish, shriek, aww, sfx } from './audio.js';
 import { splatPoint, cheer, spentBall, resolveInterlude } from './gameplay.js';
 
 export const zombies = []; // {x, z, v, walkT, variant: 'a'|'b'|'c'}
@@ -64,6 +64,7 @@ function killZombie(i, quiet) {
     t: dark ? 0.6 + Math.random() * 0.6 : 0.4 + Math.random() * 0.4, dark,
   }); }
   splat();
+  sfx('headshot-' + (Math.random() < 0.5 ? 1 : 2), 0.6); // random headshot crack layered on the gore burst
   sendBoy(zb.x, zb.z);            // a boy sprints out to mop
   if (!G.horde) splatPoint('P', quiet); // a horde is survival — it doesn't score, so it can't chain into itself
 }
@@ -195,7 +196,7 @@ export function updateZombies(dt) {
         t: 0.5 + Math.random() * 0.5,
       });
       splat(1);
-      voice('game_set_massacre', 0.8);
+      voice('game_set_massacre', 0.8); aww(1); // the run is over — the crowd groans
       G.mode = 'eaten'; ball.active = false; G.flash = null; // zombies keep shambling for ambience
       G.horde = null; pellets.length = 0; extras.length = 0; G.mgT = 0; // everything stops; the eaten screen takes over
       try { // the run is over — settle it against the best (games survived, sets as tiebreak)