playcanvas/build/playcanvas/src/framework/handlers/audio.js

PlayCanvas WebGL game engine

import { path } from '../../core/path.js';
import { Http, http } from '../../platform/net/http.js';
import { hasAudioContext } from '../../platform/sound/capabilities.js';
import { Sound } from '../../platform/sound/sound.js';
import { ResourceHandler } from './handler.js';

const ie = function() {
		if (typeof window === 'undefined') {
				return false;
		}
		const ua = window.navigator.userAgent;
		const msie = ua.indexOf('MSIE ');
		if (msie > 0) {
				return parseInt(ua.substring(msie + 5, ua.indexOf('.', msie)), 10);
		}
		const trident = ua.indexOf('Trident/');
		if (trident > 0) {
				const rv = ua.indexOf('rv:');
				return parseInt(ua.substring(rv + 3, ua.indexOf('.', rv)), 10);
		}
		return false;
}();
const supportedExtensions = [
		'.ogg',
		'.mp3',
		'.wav',
		'.mp4a',
		'.m4a',
		'.mp4',
		'.aac',
		'.opus'
];
class AudioHandler extends ResourceHandler {
		constructor(app){
				super(app, 'audio');
				this.manager = app.soundManager;
		}
		_isSupported(url) {
				const ext = path.getExtension(url);
				return supportedExtensions.indexOf(ext) > -1;
		}
		load(url, callback) {
				if (typeof url === 'string') {
						url = {
								load: url,
								original: url
						};
				}
				const success = function(resource) {
						callback(null, new Sound(resource));
				};
				const error = function(err) {
						let msg = `Error loading audio url: ${url.original}`;
						if (err) {
								msg += `: ${err.message || err}`;
						}
						console.warn(msg);
						callback(msg);
				};
				if (this._createSound) {
						if (!this._isSupported(url.original)) {
								error(`Audio format for ${url.original} not supported`);
								return;
						}
						this._createSound(url.load, success, error);
				} else {
						error(null);
				}
		}
		_createSound(url, success, error) {
				if (hasAudioContext()) {
						const manager = this.manager;
						if (!manager.context) {
								error('Audio manager has no audio context');
								return;
						}
						const options = {
								retry: this.maxRetries > 0,
								maxRetries: this.maxRetries
						};
						if (url.startsWith('blob:') || url.startsWith('data:')) {
								options.responseType = Http.ResponseType.ARRAY_BUFFER;
						}
						http.get(url, options, (err, response)=>{
								if (err) {
										error(err);
										return;
								}
								manager.context.decodeAudioData(response, success, error);
						});
				} else {
						let audio = null;
						try {
								audio = new Audio();
						} catch (e) {
								error('No support for Audio element');
								return;
						}
						if (ie) {
								document.body.appendChild(audio);
						}
						const onReady = function() {
								audio.removeEventListener('canplaythrough', onReady);
								if (ie) {
										document.body.removeChild(audio);
								}
								success(audio);
						};
						audio.onerror = function() {
								audio.onerror = null;
								if (ie) {
										document.body.removeChild(audio);
								}
								error();
						};
						audio.addEventListener('canplaythrough', onReady);
						audio.src = url;
				}
		}
}

export { AudioHandler };