Fix issues from mobile playtesting (#5)

Reviewed-on: https://home.schmelczer.dev/git/andras/decla-red/pulls/5

frontend/src/main.scss

@@ -208,7 +208,9 @@ body {
       mask-image: url('../static/mask.svg');
 
       &.contested {
-        animation: contested-pulse 0.7s ease-in-out infinite;
+        box-shadow:
+          inset 0 0 0 2px rgba(255, 255, 255, 0.7),
+          inset 0 0 3px 0px rgba(0, 0, 0, 0.2);
       }
 
       &.keystone {
@@ -320,6 +322,15 @@ body {
         display: inline-block;
       }
 
+      &[hidden] {
+        display: none;
+      }
+
+      &[aria-disabled='true'] {
+        opacity: 0.3;
+        cursor: default;
+      }
+
       &.fire {
         right: $medium-padding;
 
@@ -757,18 +768,6 @@ body {
   }
 }
 
-@keyframes contested-pulse {
-
-  0%,
-  100% {
-    opacity: 1;
-  }
-
-  50% {
-    opacity: 0.35;
-  }
-}
-
 .charge-ring {
   position: fixed;
   @include square(56px);

frontend/src/scripts/commands/touch-listener.ts

@@ -4,6 +4,7 @@ import type { Command } from 'shared';
 import type { Game } from '../game';
 import { ChargeIndicator } from '../charge-indicator';
 import { centeredTransform } from '../helper/centered-transform';
+import { localCharacterPredictor } from '../helper/prediction/local-character-predictor';
 import { InputGenerator } from './input-generator';
 
 const deadZone = 8;
@@ -196,15 +197,23 @@ export class TouchListener extends InputGenerator {
     event.stopPropagation();
   }
 
+  private get isAlive(): boolean {
+    return (this.game.gameObjects.localPlayer?.health ?? 0) > 0;
+  }
+
   private leapButtonListener = (event: TouchEvent) => {
     this.swallowTouch(event);
+    if (!this.isAlive || !localCharacterPredictor.canLeap) {
+      return;
+    }
     this.sendLeap();
+    this.leapButton.hidden = true;
   };
 
   private fireButtonDownListener = (event: TouchEvent) => {
     this.swallowTouch(event);
     const touch = event.changedTouches[0];
-    if (this.fireTouchId !== null || !touch) {
+    if (!this.isAlive || this.fireTouchId !== null || !touch) {
       return;
     }
     this.fireTouchId = touch.identifier;
@@ -255,7 +264,7 @@ export class TouchListener extends InputGenerator {
     this.cancelFire();
 
     const character = this.game.gameObjects.localPlayer;
-    if (!character) {
+    if (!character || character.health <= 0) {
       return;
     }
 
@@ -287,6 +296,11 @@ export class TouchListener extends InputGenerator {
     }
 
     const character = this.game.gameObjects.localPlayer;
+    this.fireButton.setAttribute('aria-disabled', String(!this.isAlive));
+    this.leapButton.hidden = !this.isAlive || !localCharacterPredictor.canLeap;
+    if (!this.isAlive && this.fireTouchId !== null) {
+      this.cancelFire();
+    }
     if (character) {
       this.fireStrengthRing.style.background = `conic-gradient(rgba(255, 255, 255, 0.75) ${
         character.strengthFraction * 360

frontend/src/scripts/feedback-hud.ts

@@ -3,7 +3,6 @@ import { getDisplayPosition } from './helper/pointer';
 
 let root: HTMLElement | undefined;
 let killfeed: HTMLElement | undefined;
-let elimination: HTMLElement | undefined;
 
 function ensureRoot(): { root: HTMLElement; killfeed: HTMLElement } {
   if (!root || !killfeed) {
@@ -74,27 +73,7 @@ function killConfirmed(victimName?: string, streak = 1, charge = 0) {
   }
 }
 
-function showElimination(): void {
-  if (elimination) {
-    return;
-  }
-  const { root: r } = ensureRoot();
-  const el = document.createElement('div');
-  el.className = 'elimination';
-  el.innerHTML =
-    '<div class="elimination-title">Eliminated</div>' +
-    '<div class="elimination-sub">Respawning…</div>';
-  r.appendChild(el);
-  elimination = el;
-}
-
-function hideElimination(): void {
-  elimination?.remove();
-  elimination = undefined;
-}
-
 function resetFeedbackHud(): void {
-  hideElimination();
   root?.remove();
   root = undefined;
   killfeed = undefined;
@@ -122,7 +101,5 @@ function escapeHtml(text: string): string {
 export const FeedbackHud = {
   hitMarker,
   killConfirmed,
-  showElimination,
-  hideElimination,
   reset: resetFeedbackHud,
 };

frontend/src/scripts/game.ts

@@ -55,7 +55,7 @@ export class Game extends CommandReceiver {
 
   private socket!: Socket;
   private socketReceiver!: CommandSocket;
-  private tutorial!: Tutorial;
+  private tutorial?: Tutorial;
   private resolveStarted!: () => void;
   private isBetweenGames = false;
   private isActive = true;
@@ -92,7 +92,7 @@ export class Game extends CommandReceiver {
       ),
     [GameEndCommand.name]: () => (localCharacterPredictor.enabled = false),
     [UpdateMinimap.name]: (c: UpdateMinimap) => (this.lastMinimap = c),
-    [GameStartCommand.name]: () => this.initialize(),
+    [GameStartCommand.name]: () => this.initialize(true),
   };
 
   constructor(
@@ -106,7 +106,7 @@ export class Game extends CommandReceiver {
 
     const onInput = (c: Command) => {
       this.socketReceiver.queue(c);
-      this.tutorial.handleCommand(c);
+      this.tutorial?.handleCommand(c);
     };
     this.keyboardListener = new KeyboardListener(onInput);
     this.mouseListener = new MouseListener(this.canvas, this, onInput);
@@ -117,7 +117,7 @@ export class Game extends CommandReceiver {
     this.gameObjects.handleCommand(c);
   }
 
-  private initialize() {
+  private initialize(isNewGame = false) {
     this.isBetweenGames = true;
 
     this.socket?.close();
@@ -131,14 +131,15 @@ export class Game extends CommandReceiver {
     this.keystoneArrow = undefined;
     this.connectionBanner = undefined;
     this.lastMinimap = undefined;
-    this.lastAnnouncementText = '';
+    this.lastAnnouncementText = isNewGame ? 'New game!' : '';
+    this.timeSinceLastAnnouncement = 0;
     this.announcementText.innerText = '';
     this.overlay.append(
       this.scoreboard.element,
       this.minimap.element,
       this.announcementText,
     );
-    this.tutorial = new Tutorial(this.overlay);
+    this.tutorial = isNewGame ? undefined : new Tutorial(this.overlay);
 
     this.socket = io(this.playerDecision.server, {
       reconnectionDelayMax: 10000,
@@ -281,9 +282,9 @@ export class Game extends CommandReceiver {
   public static rejectionText(reason: JoinRejectionReason): string {
     switch (reason) {
       case JoinRejectionReason.ServerFull:
-        return 'That server is full — pick another';
+        return 'That server is full. Pick another';
       case JoinRejectionReason.RoundEnding:
-        return 'That round is just finishing — try again in a moment';
+        return 'That round is just finishing. Try again in a moment';
       case JoinRejectionReason.AlreadyJoined:
         return 'Already joined on this connection';
       default:
@@ -354,7 +355,7 @@ export class Game extends CommandReceiver {
     this.gameObjects.step(deltaTime);
     this.gameObjects.render(renderer, this.overlay, shouldChangeLayout);
     this.touchListener.update();
-    this.tutorial.step(this.gameObjects);
+    this.tutorial?.step(this.gameObjects);
     this.socketReceiver.sendQueuedCommands();
 
     return this.isActive;

frontend/src/scripts/helper/prediction/local-character-predictor.ts

@@ -28,6 +28,11 @@ const maxReplayMs = 400;
 const correctionSeconds = 0.08;
 const snapDistance = 1500;
 
+interface PredictedMovementState extends CharacterMovementState {
+  availableStrength: number;
+  leapCooldownRemaining: number;
+}
+
 interface ReplaySnapshot {
   pose: { head: Circle; leftFoot: Circle; rightFoot: Circle };
   movement: CharacterMovementSnapshot;
@@ -35,7 +40,7 @@ interface ReplaySnapshot {
   leapAckMs: number;
   strength: number;
   planets: Array<PlanetSnapshot>;
-  horizonState?: CharacterMovementState;
+  horizonState?: PredictedMovementState;
 }
 
 const upwards = vec2.fromValues(0, 1);
@@ -59,6 +64,7 @@ export class LocalCharacterPredictor {
   private leapHistory: Array<number> = [];
   private lastLeapAckMs = -Infinity;
   private currentStrength = settings.playerMaxStrength;
+  private predicted?: PredictedMovementState;
 
   private alive = true;
   private previousSnapshot?: ReplaySnapshot;
@@ -79,6 +85,17 @@ export class LocalCharacterPredictor {
     return this.renderRightFoot;
   }
 
+  public get canLeap(): boolean {
+    return (
+      this.enabled &&
+      this.alive &&
+      !this.isAnimatingInOrOut &&
+      !!this.predicted?.currentPlanet &&
+      this.predicted.leapCooldownRemaining <= 0 &&
+      this.predicted.availableStrength >= settings.leapStrengthCost
+    );
+  }
+
   public recordInput(direction: vec2): number {
     const timeMs = clientTimeMs();
     this.inputHistory.record(direction, timeMs);
@@ -103,6 +120,7 @@ export class LocalCharacterPredictor {
   public recordLeap(): number {
     const timeMs = clientTimeMs();
     this.leapHistory.push(timeMs);
+    this.predicted = undefined;
     const cutoff = timeMs - 1500;
     while (this.leapHistory.length > 0 && this.leapHistory[0] <= cutoff) {
       this.leapHistory.shift();
@@ -126,6 +144,7 @@ export class LocalCharacterPredictor {
     this.replayAnchorMs = undefined;
     this.movement = undefined;
     this.currentStrength = settings.playerMaxStrength;
+    this.predicted = undefined;
     this.alive = true;
     this.previousSnapshot = undefined;
     this.lastUpdateMs = undefined;
@@ -149,6 +168,7 @@ export class LocalCharacterPredictor {
 
   public update(planets: Array<PlanetView>): boolean {
     if (!this.enabled || !this.alive || !this.canPredict || this.isAnimatingInOrOut) {
+      this.predicted = undefined;
       this.previousSnapshot = undefined;
       this.lastUpdateMs = undefined;
       vec2.zero(this.correction);
@@ -182,6 +202,7 @@ export class LocalCharacterPredictor {
             ),
           };
     const predicted = this.simulate(snapshot);
+    this.predicted = predicted;
 
     if (this.previousSnapshot && this.previousSnapshot.pose !== snapshot.pose) {
       // Compare both snapshots at the same instant: smooth only the correction,
@@ -210,7 +231,7 @@ export class LocalCharacterPredictor {
     return true;
   }
 
-  private simulate(snapshot: ReplaySnapshot): CharacterMovementState {
+  private simulate(snapshot: ReplaySnapshot): PredictedMovementState {
     if (snapshot.horizonState) {
       return snapshot.horizonState;
     }
@@ -222,7 +243,7 @@ export class LocalCharacterPredictor {
     const steps = Math.floor(windowMs / stepMs);
     const partialStep = (windowMs - steps * stepMs) / stepMs;
 
-    const state: CharacterMovementState = {
+    const state: PredictedMovementState = {
       head: makeBody(auth.head.center, auth.head.radius, upwards),
       leftFoot: makeBody(
         auth.leftFoot.center,
@@ -238,11 +259,10 @@ export class LocalCharacterPredictor {
       currentPlanet: this.world.surfaceById(movement.groundPlanetId),
       secondsSinceOnSurface: movement.secondsSinceOnSurface,
       bodyVelocity: vec2.fromValues(movement.bodyVelocity[0], movement.bodyVelocity[1]),
+      availableStrength: snapshot.strength,
+      leapCooldownRemaining: movement.leapCooldownRemaining ?? 0,
     };
 
-    let availableStrength = snapshot.strength;
-    let cooldown = movement.leapCooldownRemaining ?? 0;
-
     let t = startMs;
     for (let i = 0; i < steps + (partialStep > 0 ? 1 : 0); i++) {
       const fraction = i < steps ? 1 : partialStep;
@@ -258,12 +278,12 @@ export class LocalCharacterPredictor {
           leapMs < t + stepMs * fraction &&
           leapMs > snapshot.leapAckMs &&
           state.currentPlanet &&
-          cooldown <= 0 &&
-          availableStrength >= settings.leapStrengthCost
+          state.leapCooldownRemaining <= 0 &&
+          state.availableStrength >= settings.leapStrengthCost
         ) {
           applyLeapImpulse(state, this.inputHistory.directionAt(leapMs));
-          availableStrength -= settings.leapStrengthCost;
-          cooldown = settings.leapCooldownSeconds;
+          state.availableStrength -= settings.leapStrengthCost;
+          state.leapCooldownRemaining = settings.leapCooldownSeconds;
         }
       }
       this.world.advance(stepSeconds);
@@ -274,10 +294,14 @@ export class LocalCharacterPredictor {
         this.inputHistory.directionAt(t),
         stepSeconds,
       );
-      cooldown = Math.max(0, cooldown - stepSeconds);
-      availableStrength = Math.min(
+      state.leapCooldownRemaining = Math.max(
+        0,
+        state.leapCooldownRemaining - stepSeconds,
+      );
+      state.availableStrength = Math.min(
         settings.playerMaxStrength,
-        availableStrength + settings.playerStrengthRegenerationPerSeconds * stepSeconds,
+        state.availableStrength +
+          settings.playerStrengthRegenerationPerSeconds * stepSeconds,
       );
       if (from) {
         [state.head, state.leftFoot, state.rightFoot].forEach((body, index) =>

frontend/src/scripts/objects/game-object-container.ts

@@ -13,7 +13,6 @@ import {
   RemoteCallsForObjects,
   UpdatePropertyCommand,
 } from 'shared';
-import { FeedbackHud } from '../feedback-hud';
 import type { Game } from '../game';
 import { serverTimeline } from '../helper/server-timeline';
 import { localCharacterPredictor } from '../helper/prediction/local-character-predictor';
@@ -50,7 +49,6 @@ export class GameObjectContainer extends CommandReceiver {
       this.addObject(this.player);
       localCharacterPredictor.reset();
       this.game.resendMovement();
-      FeedbackHud.hideElimination();
       this.wasLocalPlayerAlive = true;
     },
 
@@ -133,9 +131,6 @@ export class GameObjectContainer extends CommandReceiver {
 
     const player = this.localPlayer;
     const alive = !!player && player.health > 0;
-    if (this.wasLocalPlayerAlive && !alive) {
-      FeedbackHud.showElimination();
-    }
     this.wasLocalPlayerAlive = alive;
 
     if (player) {

frontend/src/scripts/sound-handler.ts

@@ -8,37 +8,51 @@ import { options } from './options-handler';
 export const Sounds = { hit: 'hit', shoot: 'shoot', click: 'click' } as const;
 export type Sound = (typeof Sounds)[keyof typeof Sounds];
 
-let sounds: Record<Sound, HTMLAudioElement>;
+const sounds: Partial<Record<Sound, AudioBuffer>> = {};
+const maxVoices = 16;
+const voices = new Set<{ source: AudioBufferSourceNode; gain: GainNode }>();
+let context: AudioContext | undefined;
+let initialization: Promise<void> | undefined;
 let isAmbientPlaying = false;
 const ambient = new Audio(ambientAudio);
-let initialized = false;
+let ambientInitialized = false;
 
-async function initializeSound(src: string): Promise<HTMLAudioElement> {
-  const snd = new Audio(src);
-  snd.muted = true;
-  await snd.play().catch(() => undefined);
-  snd.pause();
-  snd.muted = false;
-  snd.currentTime = 0;
-  return snd;
+async function initializeEffects() {
+  try {
+    context = new AudioContext({ latencyHint: 'interactive' });
+  } catch {
+    return;
+  }
+  const audioContext = context;
+  // Unlock during the initiating gesture, before any network or decode work.
+  void audioContext.resume().catch(() => undefined);
+  await Promise.all(
+    Object.entries({ hit: hitSound, shoot: shootSound, click: clickSound }).map(
+      async ([name, src]) => {
+        try {
+          const response = await fetch(src);
+          if (response.ok) {
+            sounds[name as Sound] = await audioContext.decodeAudioData(
+              await response.arrayBuffer(),
+            );
+          }
+        } catch {
+          // Missing audio must not interrupt gameplay or prevent other effects loading.
+        }
+      },
+    ),
+  );
 }
 
-async function initialize(
-  onPlayKeypress: () => unknown = () => null,
-  onPauseKeypress: () => unknown = () => null,
+async function initializeAmbient(
+  onPlayKeypress: () => unknown,
+  onPauseKeypress: () => unknown,
 ) {
   ambient.muted = true;
   ambient.volume = 0.5;
   ambient.loop = true;
-  // Unlock every audio element during the initiating click, before awaiting any one.
-  const ambientReady = ambient.play().catch(() => undefined);
-  const [hit, shoot, click] = await Promise.all(
-    [hitSound, shootSound, clickSound].map(initializeSound),
-  );
-  sounds = { hit, shoot, click };
-
-  await ambientReady;
-  initialized = true;
+  await ambient.play().catch(() => undefined);
+  ambientInitialized = true;
   ambient.onpause = onPauseKeypress;
   ambient.onplay = onPlayKeypress;
 
@@ -49,32 +63,65 @@ async function initialize(
   }
 }
 
+function initialize(
+  onPlayKeypress: () => unknown = () => null,
+  onPauseKeypress: () => unknown = () => null,
+): Promise<void> {
+  if (!initialization) {
+    initialization = initializeEffects();
+    // Streaming music can take much longer to load than the short effects.
+    void initializeAmbient(onPlayKeypress, onPauseKeypress);
+  }
+  return initialization;
+}
+
 function play(snd: Sound, volume = 1, playbackRate = 1) {
-  if (!initialized || !options.soundsEnabled) {
+  const buffer = sounds[snd];
+  if (!context || !buffer || !options.soundsEnabled) {
+    return;
+  }
+  if (context.state !== 'running') {
+    void context.resume().catch(() => undefined);
     return;
   }
 
-  const pooled = sounds[snd];
-  const isBusy = !pooled.paused && !pooled.ended;
-  const audio = isBusy ? (pooled.cloneNode(true) as HTMLAudioElement) : pooled;
-  if (!isBusy) {
-    audio.currentTime = 0;
+  // Delayed network packets can deliver many effects together. Keep their audio work bounded.
+  if (voices.size >= maxVoices) {
+    const oldest = voices.values().next().value!;
+    oldest.source.stop();
+    oldest.source.disconnect();
+    oldest.gain.disconnect();
+    voices.delete(oldest);
   }
-  audio.volume = clamp01(volume);
-  audio.playbackRate = playbackRate;
-  void audio.play().catch(() => undefined);
+
+  const source = context.createBufferSource();
+  const gain = context.createGain();
+  source.buffer = buffer;
+  source.playbackRate.value = playbackRate;
+  gain.gain.value = clamp01(volume);
+  source.connect(gain);
+  gain.connect(context.destination);
+  const voice = { source, gain };
+  voices.add(voice);
+  source.onended = () => {
+    if (voices.delete(voice)) {
+      source.disconnect();
+      gain.disconnect();
+    }
+  };
+  source.start();
 }
 
 function playAmbient() {
   isAmbientPlaying = true;
-  if (initialized) {
+  if (ambientInitialized) {
     void ambient.play().catch(() => undefined);
   }
 }
 
 function stopAmbient() {
   isAmbientPlaying = false;
-  if (initialized) {
+  if (ambientInitialized) {
     ambient.pause();
   }
 }

frontend/src/scripts/tutorial.ts

@@ -13,10 +13,18 @@ import { PlanetView } from './objects/types/planet-view';
 
 type StageTrigger = 'move' | 'shoot' | 'leap' | 'capture';
 
-const stages: ReadonlyArray<{ hint: string; clearsOn: StageTrigger }> = [
-  { hint: 'WASD / drag to walk', clearsOn: 'move' },
-  { hint: 'Click / tap to shoot', clearsOn: 'shoot' },
-  { hint: 'Space / leap button to launch off a planet', clearsOn: 'leap' },
+const stages: ReadonlyArray<{
+  hint: string;
+  touchHint?: string;
+  clearsOn: StageTrigger;
+}> = [
+  { hint: 'WASD to walk', touchHint: 'Drag to walk', clearsOn: 'move' },
+  { hint: 'Click to shoot', touchHint: 'Tap to shoot', clearsOn: 'shoot' },
+  {
+    hint: 'Space to launch off a planet',
+    touchHint: 'Tap the leap button to launch off a planet',
+    clearsOn: 'leap',
+  },
   { hint: 'Stand on a planet to capture it', clearsOn: 'capture' },
 ];
 
@@ -54,7 +62,7 @@ export class Tutorial extends CommandReceiver {
   constructor(overlay: HTMLElement) {
     super();
     this.element.className = 'tutorial-hint';
-    this.element.innerText = stages[0].hint;
+    this.setStage(0);
     overlay.appendChild(this.element);
   }
 
@@ -107,6 +115,14 @@ export class Tutorial extends CommandReceiver {
 
   private setStage(stage: number) {
     this.stage = stage;
-    this.element.innerText = stages[stage]?.hint ?? '';
+    // Keep the hints consistent with the touch buttons' visibility in main.scss.
+    const useTouchControls = window.matchMedia(
+      '(hover: none) and (pointer: coarse)',
+    ).matches;
+    const currentStage = stages[stage];
+    this.element.innerText =
+      (useTouchControls ? currentStage?.touchHint : undefined) ??
+      currentStage?.hint ??
+      '';
   }
 }