playcanvas/build/playcanvas/src/platform/sound/manager.js

PlayCanvas WebGL game engine

import { EventHandler } from '../../core/event-handler.js';
import { math } from '../../core/math/math.js';
import { Listener } from './listener.js';

const CONTEXT_STATE_RUNNING = 'running';
const USER_INPUT_EVENTS = [
		'click',
		'touchstart',
		'mousedown'
];
class SoundManager extends EventHandler {
		constructor(){
				super();
				this._context = null;
				this.AudioContext = typeof AudioContext !== 'undefined' && AudioContext || typeof webkitAudioContext !== 'undefined' && webkitAudioContext;
				if (!this.AudioContext) ;
				this._unlockHandlerFunc = this._unlockHandler.bind(this);
				this._userSuspended = false;
				this.listener = new Listener(this);
				this._volume = 1;
		}
		set volume(volume) {
				volume = math.clamp(volume, 0, 1);
				this._volume = volume;
				this.fire('volumechange', volume);
		}
		get volume() {
				return this._volume;
		}
		get suspended() {
				return this._userSuspended;
		}
		get context() {
				if (!this._context && this.AudioContext) {
						this._context = new this.AudioContext();
						if (this._context.state !== CONTEXT_STATE_RUNNING) {
								this._registerUnlockListeners();
						}
				}
				return this._context;
		}
		suspend() {
				if (!this._userSuspended) {
						this._userSuspended = true;
						if (this._context && this._context.state === CONTEXT_STATE_RUNNING) {
								this._suspend();
						}
				}
		}
		resume() {
				if (this._userSuspended) {
						this._userSuspended = false;
						if (this._context && this._context.state !== CONTEXT_STATE_RUNNING) {
								this._resume();
						}
				}
		}
		destroy() {
				this.fire('destroy');
				if (this._context) {
						this._removeUnlockListeners();
						this._context?.close();
						this._context = null;
				}
		}
		_resume() {
				this._context.resume().then(()=>{
						const source = this._context.createBufferSource();
						source.buffer = this._context.createBuffer(1, 1, this._context.sampleRate);
						source.connect(this._context.destination);
						source.start(0);
						source.onended = (event)=>{
								source.disconnect(0);
								this.fire('resume');
						};
				}, (e)=>{}).catch((e)=>{});
		}
		_suspend() {
				this._context.suspend().then(()=>{
						this.fire('suspend');
				}, (e)=>{}).catch((e)=>{});
		}
		_unlockHandler() {
				this._removeUnlockListeners();
				if (!this._userSuspended && this._context.state !== CONTEXT_STATE_RUNNING) {
						this._resume();
				}
		}
		_registerUnlockListeners() {
				USER_INPUT_EVENTS.forEach((eventName)=>{
						window.addEventListener(eventName, this._unlockHandlerFunc, false);
				});
		}
		_removeUnlockListeners() {
				USER_INPUT_EVENTS.forEach((eventName)=>{
						window.removeEventListener(eventName, this._unlockHandlerFunc, false);
				});
		}
}

export { SoundManager };