lettuce
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Lettuce JS, Mini Mobile Framework for Romantic with DSL.
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JavaScript
/*!
* howler.js v2.0.0-beta
* howlerjs.com
*
* (c) 2013-2014, James Simpson of GoldFire Studios
* goldfirestudios.com
*
* MIT License
*/
/* jshint -W003 */
/* jshint -W013 */
/* jshint -W015 */
/* jshint -W031 */
/* jshint -W083 */
/* jshint -W098 */
/* jshint -W108 */
/* jshint -W116 */
(function() {
'use strict';
// Setup our audio context.
var ctx = null;
var usingWebAudio = true;
var noAudio = false;
setupAudioContext();
// Create a master gain node.
if (usingWebAudio) {
var masterGain = (typeof ctx.createGain === 'undefined') ? ctx.createGainNode() : ctx.createGain();
masterGain.gain.value = 1;
masterGain.connect(ctx.destination);
}
/** Global Methods **/
/***************************************************************************/
/**
* Create the global controller. All contained methods and properties apply
* to all sounds that are currently playing or will be in the future.
*/
var HowlerGlobal = function() {
this.init();
};
HowlerGlobal.prototype = {
/**
* Initialize the global Howler object.
* @return {Howler}
*/
init: function() {
var self = this || Howler;
// Internal properties.
self._codecs = {};
self._howls = [];
self._muted = false;
self._volume = 1;
// Set to false to disable the auto iOS enabler.
self.iOSAutoEnable = true;
// No audio is available on this system if this is set to true.
self.noAudio = noAudio;
// This will be true if the Web Audio API is available.
self.usingWebAudio = usingWebAudio;
// Expose the AudioContext when using Web Audio.
self.ctx = ctx;
// Check for supported codecs.
if (!noAudio) {
self._setupCodecs();
}
return self;
},
/**
* Get/set the global volume for all sounds.
* @param {Float} vol Volume from 0.0 to 1.0.
* @return {Howler/Float} Returns self or current volume.
*/
volume: function(vol) {
var self = this || Howler;
vol = parseFloat(vol);
if (typeof vol !== 'undefined' && vol >= 0 && vol <= 1) {
self._volume = vol;
// When using Web Audio, we just need to adjust the master gain.
if (usingWebAudio) {
masterGain.gain.value = vol;
}
// Loop through and change volume for all HTML5 audio nodes.
for (var i=0; i<self._howls.length; i++) {
if (!self._howls[i]._webAudio) {
// Get all of the sounds in this Howl group.
var ids = self._howls[i]._getSoundIds();
// Loop through all sounds and change the volumes.
for (var j=0; j<ids.length; j++) {
var sound = self._howls[i]._soundById(ids[j]);
if (sound && sound._node) {
sound._node.volume = sound._volume * vol;
}
}
}
}
return self;
}
return self._volume;
},
/**
* Handle muting and unmuting globally.
* @param {Boolean} muted Is muted or not.
*/
mute: function(muted) {
var self = this || Howler;
self._muted = muted;
// With Web Audio, we just need to mute the master gain.
if (usingWebAudio) {
masterGain.gain.value = muted ? 0 : self._volume;
}
// Loop through and mute all HTML5 Audio nodes.
for (var i=0; i<self._howls.length; i++) {
if (!self._howls[i]._webAudio) {
// Get all of the sounds in this Howl group.
var ids = self._howls[i]._getSoundIds();
// Loop through all sounds and mark the audio node as muted.
for (var j=0; j<ids.length; j++) {
var sound = self._howls[i]._soundById(ids[j]);
if (sound && sound._node) {
sound._node.muted = (muted) ? true : sound._muted;
}
}
}
}
return self;
},
/**
* Check for codec support of specific extension.
* @param {String} ext Audio file extention.
* @return {Boolean}
*/
codecs: function(ext) {
return (this || Howler)._codecs[ext];
},
/**
* Check for browser support for various codecs and cache the results.
* @return {Howler}
*/
_setupCodecs: function() {
var self = this || Howler;
var audioTest = new Audio();
self._codecs = {
mp3: !!audioTest.canPlayType('audio/mpeg;').replace(/^no$/, ''),
opus: !!audioTest.canPlayType('audio/ogg; codecs="opus"').replace(/^no$/, ''),
ogg: !!audioTest.canPlayType('audio/ogg; codecs="vorbis"').replace(/^no$/, ''),
wav: !!audioTest.canPlayType('audio/wav; codecs="1"').replace(/^no$/, ''),
aac: !!audioTest.canPlayType('audio/aac;').replace(/^no$/, ''),
m4a: !!(audioTest.canPlayType('audio/x-m4a;') || audioTest.canPlayType('audio/m4a;') || audioTest.canPlayType('audio/aac;')).replace(/^no$/, ''),
mp4: !!(audioTest.canPlayType('audio/x-mp4;') || audioTest.canPlayType('audio/mp4;') || audioTest.canPlayType('audio/aac;')).replace(/^no$/, ''),
weba: !!audioTest.canPlayType('audio/webm; codecs="vorbis"').replace(/^no$/, ''),
webm: !!audioTest.canPlayType('audio/webm; codecs="vorbis"').replace(/^no$/, '')
};
return self;
},
/**
* iOS will only allow audio to be played after a user interaction.
* Attempt to automatically unlock audio on the first user interaction.
* Concept from: http://paulbakaus.com/tutorials/html5/web-audio-on-ios/
* @return {Howler}
*/
_enableiOSAudio: function() {
var self = this || Howler;
// Only run this on iOS if audio isn't already eanbled.
if (ctx && (self._iOSEnabled || !/iPhone|iPad|iPod/i.test(navigator.userAgent))) {
return;
}
self._iOSEnabled = false;
// Call this method on touch start to create and play a buffer,
// then check if the audio actually played to determine if
// audio has now been unlocked on iOS.
var unlock = function() {
// Create an empty buffer.
var buffer = ctx.createBuffer(1, 1, 22050);
var source = ctx.createBufferSource();
source.buffer = buffer;
source.connect(ctx.destination);
// Play the empty buffer.
if (typeof source.start === 'undefined') {
source.noteOn(0);
} else {
source.start(0);
}
// Setup a timeout to check that we are unlocked on the next event loop.
setTimeout(function() {
if ((source.playbackState === source.PLAYING_STATE || source.playbackState === source.FINISHED_STATE)) {
// Update the unlocked state and prevent this check from happening again.
self._iOSEnabled = true;
self.iOSAutoEnable = false;
// Remove the touch start listener.
window.removeEventListener('touchstart', unlock, false);
}
}, 0);
};
// Setup a touch start listener to attempt an unlock in.
window.addEventListener('touchstart', unlock, false);
return self;
}
};
// Setup the global audio controller.
var Howler = new HowlerGlobal();
/** Group Methods **/
/***************************************************************************/
/**
* Create an audio group controller.
* @param {Object} o Passed in properties for this group.
*/
var Howl = function(o) {
var self = this;
// Throw an error if no source is provided
if (!o.src) {
console.error('An array of source files must be passed with any new Howl.');
return;
}
self.init(o);
};
Howl.prototype = {
/**
* Initialize a new Howl group object.
* @param {Object} o Passed in properties for this group.
* @return {Howl}
*/
init: function(o) {
var self = this;
// Setup user-defined default properties.
self._autoplay = o.autoplay || false;
self._ext = o.ext || null;
self._html5 = o.html5 || false;
self._muted = o.mute || false;
self._loop = o.loop || false;
self._pool = o.pool || 5;
self._preload = (typeof o.preload === 'boolean') ? o.preload : true;
self._rate = o.rate || 1;
self._sprite = o.sprite || {};
self._src = (typeof o.src !== 'string') ? o.src : [o.src];
self._volume = o.volume !== undefined ? o.volume : 1;
// Setup all other default properties.
self._duration = 0;
self._loaded = false;
self._sounds = [];
self._endTimers = {};
// Setup event listeners.
self._onend = o.onend ? [{fn: o.onend}] : [];
self._onfaded = o.onfaded ? [{fn: o.onfaded}] : [];
self._onload = o.onload ? [{fn: o.onload}] : [];
self._onloaderror = o.onloaderror ? [{fn: o.onloaderror}] : [];
self._onpause = o.onpause ? [{fn: o.onpause}] : [];
self._onplay = o.onplay ? [{fn: o.onplay}] : [];
// Web Audio or HTML5 Audio?
self._webAudio = usingWebAudio && !self._html5;
// Automatically try to enable audio on iOS.
if (typeof ctx !== 'undefined' && ctx && Howler.iOSAutoEnable) {
Howler._enableiOSAudio();
}
// Keep track of this Howl group in the global controller.
Howler._howls.push(self);
// Load the source file unless otherwise specified.
if (self._preload) {
self.load();
}
return self;
},
/**
* Load the audio file.
* @return {Howler}
*/
load: function() {
var self = this;
var url = null;
// If no audio is available, quit immediately.
if (noAudio) {
self._emit('loaderror');
return;
}
// Make sure our source is in an array.
if (typeof self._src === 'string') {
self._src = [self._src];
}
// Loop through the sources and pick the first one that is compatible.
for (var i=0; i<self._src.length; i++) {
var ext, str;
if (self._ext && self._ext[i]) {
// If an extension was specified, use that instead.
ext = self._ext[i];
} else {
// Extract the file extension from the URL or base64 data URI.
str = self._src[i];
ext = /^data:audio\/([^;,]+);/i.exec(str);
if (!ext) {
ext = /\.([^.]+)$/.exec(str.split('?', 1)[0]);
}
if (ext) {
ext = ext[1].toLowerCase();
}
}
// Check if this extension is available.
if (Howler.codecs(ext)) {
url = self._src[i];
break;
}
}
if (!url) {
self._emit('loaderror');
return;
}
self._src = url;
// Create a new sound object and add it to the pool.
new Sound(self);
// Load and decode the audio data for playback.
if (self._webAudio) {
loadBuffer(self);
}
return self;
},
/**
* Play a sound or resume previous playback.
* @param {String/Number} sprite Sprite name for sprite playback or sound id to continue previous.
* @return {Number} Sound ID.
*/
play: function(sprite) {
var self = this;
var id = null;
// Determine if a sprite, sound id or nothing was passed
if (typeof sprite === 'number') {
id = sprite;
sprite = null;
} else if (typeof sprite === 'undefined') {
// Use the default sound sprite (plays the full audio length).
sprite = '__default';
// Check if there is a single paused sound that isn't ended.
// If there is, play that sound. If not, continue as usual.
var num = 0;
for (var i=0; i<self._sounds.length; i++) {
if (self._sounds[i]._paused && !self._sounds[i]._ended) {
num++;
id = self._sounds[i]._id;
}
}
if (num === 1) {
sprite = null;
} else {
id = null;
}
}
// Get the selected node, or get one from the pool.
var sound = id ? self._soundById(id) : self._inactiveSound();
if (id && !sprite) {
sprite = sound._sprite || '__default';
}
// If the sound doesn't exist, do nothing.
if (!sound) {
return null;
}
// If we have no sprite and the sound hasn't loaded, we must wait
// for the sound to load to get our audio's duration.
if (!self._loaded && !self._sprite[sprite]) {
self.once('load', function() {
self.play(self._soundById(sound._id) ? sound._id : undefined);
});
return sound._id;
}
// Don't play the sound if an id was passed and it is already playing.
if (id && !sound._paused) {
return sound._id;
}
// Determine how long to play for and where to start playing.
var seek = sound._seek > 0 ? sound._seek : self._sprite[sprite][0] / 1000;
var duration = ((self._sprite[sprite][0] + self._sprite[sprite][1]) / 1000) - seek;
// Create a timer to fire at the end of playback or the start of a new loop.
var ended = function() {
// Should this sound loop?
var loop = !!(sound._loop || self._sprite[sprite][2]);
// Fire the ended event.
self._emit('end', sound._id);
// Restart the playback for HTML5 Audio loop.
if (!self._webAudio && loop) {
self.stop(sound._id).play(sound._id);
}
// Restart this timer if on a Web Audio loop.
if (self._webAudio && loop) {
self._emit('play', sound._id);
sound._seek = sound._start || 0;
sound._playStart = ctx.currentTime;
self._endTimers[sound._id] = setTimeout(ended, ((sound._stop - sound._start) * 1000) / Math.abs(self._rate));
}
// Mark the node as paused.
if (self._webAudio && !loop) {
sound._paused = true;
sound._ended = true;
sound._seek = sound._start || 0;
self._clearTimer(sound._id);
// Clean up the buffer source.
sound._node.bufferSource = null;
}
// When using a sprite, end the track.
if (!self._webAudio && !loop) {
self.stop(sound._id);
}
};
self._endTimers[sound._id] = setTimeout(ended, (duration * 1000) / Math.abs(self._rate));
// Update the parameters of the sound
sound._paused = false;
sound._ended = false;
sound._sprite = sprite;
sound._seek = seek;
sound._start = self._sprite[sprite][0] / 1000;
sound._stop = (self._sprite[sprite][0] + self._sprite[sprite][1]) / 1000;
sound._loop = !!(sound._loop || self._sprite[sprite][2]);
// Begin the actual playback.
var node = sound._node;
if (self._webAudio) {
// Fire this when the sound is ready to play to begin Web Audio playback.
var playWebAudio = function() {
self._refreshBuffer(sound);
// Setup the playback params.
var vol = (sound._muted || self._muted) ? 0 : sound._volume * Howler.volume();
node.gain.setValueAtTime(vol, ctx.currentTime);
sound._playStart = ctx.currentTime;
// Play the sound using the supported method.
if (typeof node.bufferSource.start === 'undefined') {
node.bufferSource.noteGrainOn(0, seek, duration);
} else {
node.bufferSource.start(0, seek, duration);
}
// Start a new timer if none is present.
if (!self._endTimers[sound._id]) {
self._endTimers[sound._id] = setTimeout(ended, (duration * 1000) / Math.abs(self._rate));
}
setTimeout(function() {
self._emit('play', sound._id);
}, 0);
};
if (self._loaded) {
playWebAudio();
} else {
// Wait for the audio to load and then begin playback.
self.once('load', playWebAudio);
// Cancel the end timer.
self._clearTimer(sound._id);
}
} else {
// Fire this when the sound is ready to play to begin HTML5 Audio playback.
var playHtml5 = function() {
node.currentTime = seek;
node.muted = sound._muted || self._muted || Howler._muted || node.muted;
node.volume = sound._volume * Howler.volume();
node.playbackRate = self._rate;
setTimeout(function() {
node.play();
self._emit('play', sound._id);
}, 0);
};
// Play immediately if ready, or wait for the 'canplaythrough'e vent.
if (node.readyState === 4 || !node.readyState && navigator.isCocoonJS) {
playHtml5();
} else {
var listener = function() {
// Setup the new end timer.
self._endTimers[sound._id] = setTimeout(ended, (duration * 1000) / Math.abs(self._rate));
// Begin playback.
playHtml5();
// Clear this listener.
node.removeEventListener('canplaythrough', listener, false);
};
node.addEventListener('canplaythrough', listener, false);
// Cancel the end timer.
self._clearTimer(sound._id);
}
}
return sound._id;
},
/**
* Pause playback and save current position.
* @param {Number} id The sound ID (empty to pause all in group).
* @return {Howl}
*/
pause: function(id) {
var self = this;
// Wait for the sound to begin playing before pausing it.
if (!self._loaded) {
self.once('play', function() {
self.pause(id);
});
return self;
}
// If no id is passed, get all ID's to be paused.
var ids = self._getSoundIds(id);
for (var i=0; i<ids.length; i++) {
// Clear the end timer.
self._clearTimer(ids[i]);
// Get the sound.
var sound = self._soundById(ids[i]);
if (sound && !sound._paused) {
// Reset the seek position.
sound._seek = self.seek(ids[i]);
sound._paused = true;
if (self._webAudio) {
// make sure the sound has been created
if (!sound._node.bufferSource) {
return self;
}
if (typeof sound._node.bufferSource.stop === 'undefined') {
sound._node.bufferSource.noteOff(0);
} else {
sound._node.bufferSource.stop(0);
}
// Clean up the buffer source.
sound._node.bufferSource = null;
} else if (!isNaN(sound._node.duration)) {
sound._node.pause();
}
// Fire the pause event, unless `true` is passed as the 2nd argument.
if (!arguments[1]) {
self._emit('pause', sound._id);
}
}
}
return self;
},
/**
* Stop playback and reset to start.
* @param {Number} id The sound ID (empty to stop all in group).
* @return {Howl}
*/
stop: function(id) {
var self = this;
// Wait for the sound to begin playing before stopping it.
if (!self._loaded) {
if (typeof self._sounds[0]._sprite !== 'undefined') {
self.once('play', function() {
self.stop(id);
});
}
return self;
}
// If no id is passed, get all ID's to be stopped.
var ids = self._getSoundIds(id);
for (var i=0; i<ids.length; i++) {
// Clear the end timer.
self._clearTimer(ids[i]);
// Get the sound.
var sound = self._soundById(ids[i]);
if (sound && !sound._paused) {
// Reset the seek position.
sound._seek = sound._start || 0;
sound._paused = true;
sound._ended = true;
if (self._webAudio) {
// make sure the sound has been created
if (!sound._node.bufferSource) {
return self;
}
if (typeof sound._node.bufferSource.stop === 'undefined') {
sound._node.bufferSource.noteOff(0);
} else {
sound._node.bufferSource.stop(0);
}
// Clean up the buffer source.
sound._node.bufferSource = null;
} else if (!isNaN(sound._node.duration)) {
sound._node.pause();
sound._node.currentTime = sound._start || 0;
}
}
}
return self;
},
/**
* Mute/unmute a single sound or all sounds in this Howl group.
* @param {Boolean} muted Set to true to mute and false to unmute.
* @param {Number} id The sound ID to update (omit to mute/unmute all).
* @return {Howl}
*/
mute: function(muted, id) {
var self = this;
// Wait for the sound to begin playing before muting it.
if (!self._loaded) {
self.once('play', function() {
self.mute(muted, id);
});
return self;
}
// If applying mute/unmute to all sounds, update the group's value.
if (typeof id === 'undefined') {
if (typeof muted === 'boolean') {
self._muted = muted;
} else {
return self._muted;
}
}
// If no id is passed, get all ID's to be muted.
var ids = self._getSoundIds(id);
for (var i=0; i<ids.length; i++) {
// Get the sound.
var sound = self._soundById(ids[i]);
if (sound) {
sound._muted = muted;
if (self._webAudio && sound._node) {
sound._node.gain.setValueAtTime(muted ? 0 : sound._volume * Howler.volume(), ctx.currentTime);
} else if (sound._node) {
sound._node.muted = Howler._muted ? true : muted;
}
}
}
return self;
},
/**
* Get/set the volume of this sound or of the Howl group. This method can optionally take 0, 1 or 2 arguments.
* volume() -> Returns the group's volume value.
* volume(id) -> Returns the sound id's current volume.
* volume(vol) -> Sets the volume of all sounds in this Howl group.
* volume(vol, id) -> Sets the volume of passed sound id.
* @return {Howl/Number} Returns self or current volume.
*/
volume: function() {
var self = this;
var args = arguments;
var vol, id;
// Determine the values based on arguments.
if (args.length === 0) {
// Return the value of the groups' volume.
return self._volume;
} else if (args.length === 1) {
// First check if this is an ID, and if not, assume it is a new volume.
var ids = self._getSoundIds();
var index = ids.indexOf(args[0]);
if (index >= 0) {
id = parseInt(args[0], 10);
} else {
vol = parseFloat(args[0]);
}
} else if (args.length === 2) {
vol = parseFloat(args[0]);
id = parseInt(args[1], 10);
}
// Update the volume or return the current volume.
var sound;
if (typeof vol !== 'undefined' && vol >= 0 && vol <= 1) {
// Wait for the sound to begin playing before changing the volume.
if (!self._loaded) {
self.once('play', function() {
self.volume.apply(self, args);
});
return self;
}
// Set the group volume.
if (typeof id === 'undefined') {
self._volume = vol;
}
// Update one or all volumes.
id = self._getSoundIds(id);
for (var i=0; i<id.length; i++) {
// Get the sound.
sound = self._soundById(id[i]);
if (sound) {
sound._volume = vol;
if (self._webAudio && sound._node) {
sound._node.gain.setValueAtTime(vol * Howler.volume(), ctx.currentTime);
} else if (sound._node) {
sound._node.volume = vol * Howler.volume();
}
}
}
} else {
sound = id ? self._soundById(id) : self._sounds[0];
return sound ? sound._volume : 0;
}
return self;
},
/**
* Fade a currently playing sound between two volumes (if no id is passsed, all sounds will fade).
* @param {Number} from The value to fade from (0.0 to 1.0).
* @param {Number} to The volume to fade to (0.0 to 1.0).
* @param {Number} len Time in milliseconds to fade.
* @param {Number} id The sound id (omit to fade all sounds).
* @return {Howl}
*/
fade: function(from, to, len, id) {
var self = this;
// Wait for the sound to play before fading.
if (!self._loaded) {
self.once('play', function() {
self.fade(from, to, len, id);
});
return self;
}
// Set the volume to the start position.
self.volume(from, id);
// Fade the volume of one or all sounds.
var ids = self._getSoundIds(id);
for (var i=0; i<ids.length; i++) {
// Get the sound.
var sound = self._soundById(ids[i]);
// Create a linear fade or fall back to timeouts with HTML5 Audio.
if (sound) {
if (self._webAudio) {
var currentTime = ctx.currentTime;
var end = currentTime + (len / 1000);
sound._volume = from;
sound._node.gain.setValueAtTime(from, currentTime);
sound._node.gain.linearRampToValueAtTime(to, end);
// Fire the event when complete.
setTimeout(function(id, sound) {
setTimeout(function() {
sound._volume = to;
self._emit('faded', id);
}, end - ctx.currentTime > 0 ? Math.ceil((end - ctx.currentTime) * 1000) : 0);
}.bind(self, ids[i], sound), len);
} else {
var diff = Math.abs(from - to);
var dir = from > to ? 'out' : 'in';
var steps = diff / 0.01;
var stepLen = len / steps;
(function() {
var vol = from;
var interval = setInterval(function(id) {
// Update the volume amount.
vol += (dir === 'in' ? 0.01 : -0.01);
// Make sure the volume is in the right bounds.
vol = Math.max(0, vol);
vol = Math.min(1, vol);
// Round to within 2 decimal points.
vol = Math.round(vol * 100) / 100;
// Change the volume.
self.volume(vol, id);
// When the fade is complete, stop it and fire event.
if (vol === to) {
clearInterval(interval);
self._emit('faded', id);
}
}.bind(self, ids[i]), stepLen);
})();
}
}
}
return self;
},
/**
* Get/set the loop parameter on a sound. This method can optionally take 0, 1 or 2 arguments.
* loop() -> Returns the group's loop value.
* loop(id) -> Returns the sound id's loop value.
* loop(loop) -> Sets the loop value for all sounds in this Howl group.
* loop(loop, id) -> Sets the loop value of passed sound id.
* @return {Howl/Boolean} Returns self or current loop value.
*/
loop: function() {
var self = this;
var args = arguments;
var loop, id, sound;
// Determine the values for loop and id.
if (args.length === 0) {
// Return the grou's loop value.
return self._loop;
} else if (args.length === 1) {
if (typeof args[0] === 'boolean') {
loop = args[0];
self._loop = loop;
} else {
// Return this sound's loop value.
sound = self._soundById(parseInt(args[0], 10));
return sound ? sound._loop : false;
}
} else if (args.length === 2) {
loop = args[0];
id = parseInt(args[1], 10);
}
// If no id is passed, get all ID's to be looped.
var ids = self._getSoundIds(id);
for (var i=0; i<ids.length; i++) {
sound = self._soundById(ids[i]);
if (sound) {
sound._loop = loop;
if (self._webAudio && sound._node) {
sound._node.bufferSource.loop = loop;
}
}
}
return self;
},
/**
* Get/set the seek position of a sound. This method can optionally take 0, 1 or 2 arguments.
* seek() -> Returns the first sound node's current seek position.
* seek(id) -> Returns the sound id's current seek position.
* seek(seek) -> Sets the seek position of the first sound node.
* seek(seek, id) -> Sets the seek position of passed sound id.
* @return {Howl/Number} Returns self or the current seek position.
*/
seek: function() {
var self = this;
var args = arguments;
var seek, id;
// Determine the values based on arguments.
if (args.length === 0) {
// We will simply return the current position of the first node.
id = self._sounds[0]._id;
} else if (args.length === 1) {
// First check if this is an ID, and if not, assume it is a new seek position.
var ids = self._getSoundIds();
var index = ids.indexOf(args[0]);
if (index >= 0) {
id = parseInt(args[0], 10);
} else {
id = self._sounds[0]._id;
seek = parseFloat(args[0]);
}
} else if (args.length === 2) {
seek = parseFloat(args[0]);
id = parseInt(args[1], 10);
}
// If there is no ID, bail out.
if (typeof id === 'undefined') {
return self;
}
// Wait for the sound to load before seeking it.
if (!self._loaded) {
self.once('load', function() {
self.seek.apply(self, args);
});
return self;
}
// Get the sound.
var sound = self._soundById(id);
if (sound) {
if (seek >= 0) {
// Pause the sound and update position for restarting playback.
var playing = self.playing(id);
if (playing) {
self.pause(id, true);
}
// Move the position of the track and cancel timer.
sound._seek = seek;
self._clearTimer(id);
// Restart the playback if the sound was playing.
if (playing) {
self.play(id);
}
} else {
return (self._webAudio) ? sound._seek + (ctx.currentTime - sound._playStart) : sound._node.currentTime;
}
}
return self;
},
/**
* Check if a specific sound is currently playing or not.
* @param {Number} id The sound id to check. If none is passed, first sound is used.
* @return {Boolean} True if playing and false if not.
*/
playing: function(id) {
var self = this;
var sound = self._soundById(id) || self._sounds[0];
return sound ? !sound._paused : false;
},
/**
* Get the duration of this sound.
* @return {Number} Audio duration.
*/
duration: function() {
return this._duration;
},
/**
* Unload and destroy the current Howl object.
* This will immediately stop all sound instances attached to this group.
*/
unload: function() {
var self = this;
// Stop playing any active sounds.
var sounds = self._sounds;
for (var i=0; i<sounds.length; i++) {
// Stop the sound if it is currently playing.
if (!sounds[i]._paused) {
self.stop(sounds[i]._id);
self._emit('end', sounds[i]._id);
}
// Remove the source or disconnect.
if (!self._webAudio) {
// Set the source to an empty string to stop any downloading.
sounds[i]._node.src = '';
// Remove any event listeners.
sounds[i]._node.removeEventListener('error', sounds[i]._errorFn, false);
sounds[i]._node.removeEventListener('canplaythrough', sounds[i]._loadFn, false);
}
// Empty out all of the nodes.
delete sounds[i]._node;
// Make sure all timers are cleared out.
self._clearTimer(sounds[i]._id);
// Remove the references in the global Howler object.
var index = Howler._howls.indexOf(self);
if (index >= 0) {
Howler._howls.splice(index, 1);
}
}
// Delete this sound from the cache.
if (cache) {
delete cache[self._src];
}
// Clear out `self`.
self = null;
return null;
},
/**
* Listen to a custom event.
* @param {String} event Event name.
* @param {Function} fn Listener to call.
* @param {Number} id (optional) Only listen to events for this sound.
* @return {Howl}
*/
on: function(event, fn, id) {
var self = this;
var events = self['_on' + event];
if (typeof fn === 'function') {
events.push({id: id, fn: fn});
}
return self;
},
/**
* Remove a custom event.
* @param {String} event Event name.
* @param {Function} fn Listener to remove. Leave empty to remove all.
* @param {Number} id (optional) Only remove events for this sound.
* @return {Howl}
*/
off: function(event, fn, id) {
var self = this;
var events = self['_on' + event];
if (fn) {
// Loop through event store and remove the passed function.
for (var i=0; i<events.length; i++) {
if (fn === events[i].fn && id === events[i].id) {
events.splice(i, 1);
break;
}
}
} else {
// Clear out all events of this type.
events = [];
}
return self;
},
/**
* Listen to a custom event and remove it once fired.
* @param {String} event Event name.
* @param {Function} fn Listener to call.
* @param {Number} id (optional) Only listen to events for this sound.
* @return {Howl}
*/
once: function(event, fn, id) {
var self = this;
// Create the listener method.
var listener = function() {
// Call the passed function.
fn.apply(self, arguments);
// Clear the listener.
self.off(event, listener, id);
};
// Setup the event listener.
self.on(event, listener, id);
return self;
},
/**
* Emit all events of a specific type and pass the sound id.
* @param {String} event Event name.
* @param {Number} id Sound ID.
* @param {Number} msg Message to go with event.
* @return {Howl}
*/
_emit: function(event, id, msg) {
var self = this;
var events = self['_on' + event];
// Loop through event store and fire all functions.
for (var i=0; i<events.length; i++) {
if (!events[i].id || events[i].id === id) {
setTimeout(function(fn) {
fn.call(this, id, msg);
}.bind(self, events[i].fn), 0);
}
}
return self;
},
/**
* Clear the end timer for a sound playback.
* @param {Number} id The sound ID.
* @return {Howl}
*/
_clearTimer: function(id) {
var self = this;
if (self._endTimers[id]) {
clearTimeout(self._endTimers[id]);
delete self._endTimers[id];
}
return self;
},
/**
* Return the sound identified by this ID, or return null.
* @param {Number} id Sound ID
* @return {Object} Sound object or null.
*/
_soundById: function(id) {
var self = this;
// Loop through all sounds and find the one with this ID.
for (var i=0; i<self._sounds.length; i++) {
if (id === self._sounds[i]._id) {
return self._sounds[i];
}
}
return null;
},
/**
* Return an inactive sound from the pool or create a new one.
* @return {Sound} Sound playback object.
*/
_inactiveSound: function() {
var self = this;
self._drain();
// Find the first inactive node to recycle.
for (var i=0; i<self._sounds.length; i++) {
if (self._sounds[i]._ended) {
return self._sounds[i].reset();
}
}
// If no inactive node was found, create a new one.
return new Sound(self);
},
/**
* Drain excess inactive sounds from the pool.
*/
_drain: function() {
var self = this;
var limit = self._pool;
var cnt = 0;
var i = 0;
// If there are less sounds than the max pool size, we are done.
if (self._sounds.length < limit) {
return;
}
// Count the number of inactive sounds.
for (i=0; i<self._sounds.length; i++) {
if (self._sounds[i]._ended) {
cnt++;
}
}
// Remove excess inactive sounds, going in reverse order.
for (i=self._sounds.length - 1; i>=0; i--) {
if (cnt <= limit) {
return;
}
if (self._sounds[i]._ended) {
// Disconnect the audio source when using Web Audio.
if (self._webAudio && self._sounds[i]._node) {
self._sounds[i]._node.disconnect(0);
}
// Remove sounds until we have the pool size.
self._sounds.splice(i, 1);
cnt--;
}
}
},
/**
* Get all ID's from the sounds pool.
* @param {Number} id Only return one ID if one is passed.
* @return {Array} Array of IDs.
*/
_getSoundIds: function(id) {
var self = this;
if (typeof id === 'undefined') {
var ids = [];
for (var i=0; i<self._sounds.length; i++) {
ids.push(self._sounds[i]._id);
}
return ids;
} else {
return [id];
}
},
/**
* Load the sound back into the buffer source.
* @param {Sound} sound The sound object to work with.
* @return {Howl}
*/
_refreshBuffer: function(sound) {
var self = this;
// Setup the buffer source for playback.
sound._node.bufferSource = ctx.createBufferSource();
sound._node.bufferSource.buffer = cache[self._src];
// Connect to the correct node.
if (sound._panner) {
sound._node.bufferSource.connect(sound._panner);
} else {
sound._node.bufferSource.connect(sound._node);
}
// Setup looping and playback rate.
sound._node.bufferSource.loop = sound._loop;
if (sound._loop) {
sound._node.bufferSource.loopStart = sound._start || 0;
sound._node.bufferSource.loopEnd = sound._stop;
}
sound._node.bufferSource.playbackRate.value = self._rate;
return self;
}
};
/** Single Sound Methods **/
/***************************************************************************/
/**
* Setup the sound object, which each node attached to a Howl group is contained in.
* @param {Object} howl The Howl parent group.
*/
var Sound = function(howl) {
this._parent = howl;
this.init();
};
Sound.prototype = {
/**
* Initialize a new Sound object.
* @return {Sound}
*/
init: function() {
var self = this;
var parent = self._parent;
// Setup the default parameters.
self._muted = parent._muted;
self._loop = parent._loop;
self._volume = parent._volume;
self._muted = parent._muted;
self._seek = 0;
self._paused = true;
self._ended = true;
// Generate a unique ID for this sound.
self._id = Math.round(Date.now() * Math.random());
// Add itself to the parent's pool.
parent._sounds.push(self);
// Create the new node.
self.create();
return self;
},
/**
* Create and setup a new sound object, whether HTML5 Audio or Web Audio.
* @return {Sound}
*/
create: function() {
var self = this;
var parent = self._parent;
var volume = (Howler._muted || self._muted || self._parent._muted) ? 0 : self._volume * Howler.volume();
if (parent._webAudio) {
// Create the gain node for controlling volume (the source will connect to this).
self._node = (typeof ctx.createGain === 'undefined') ? ctx.createGainNode() : ctx.createGain();
self._node.gain.setValueAtTime(volume, ctx.currentTime);
self._node.paused = true;
self._node.connect(masterGain);
} else {
self._node = new Audio();
// Listen for errors (http://dev.w3.org/html5/spec-author-view/spec.html#mediaerror).
self._errorFn = self._errorListener.bind(self);
self._node.addEventListener('error', self._errorFn, false);
// Listen for 'canplaythrough' event to let us know the sound is ready.
self._loadFn = self._loadListener.bind(self);
self._node.addEventListener('canplaythrough', self._loadFn, false);
// Setup the new audio node.
self._node.src = parent._src;
self._node.preload = 'auto';
self._node.volume = volume;
// Begin loading the source.
self._node.load();
}
return self;
},
/**
* Reset the parameters of this sound to the original state (for recycle).
* @return {Sound}
*/
reset: function() {
var self = this;
var parent = self._parent;
// Reset all of the parameters of this sound.
self._muted = parent._muted;
self._loop = parent._loop;
self._volume = parent._volume;
self._muted = parent._muted;
self._seek = 0;
self._paused = true;
self._ended = true;
self._sprite = null;
// Generate a new ID so that it isn't confused with the previous sound.
self._id = Math.round(Date.now() * Math.random());
return self;
},
/**
* HTML5 Audio error listener callback.
*/
_errorListener: function() {
var self = this;
if (self._node.error && self._node.error.code === 4) {
Howler.noAudio = true;
}
// Fire an error event and pass back the code.
self._parent._emit('loaderror', self._id, self._node.error ? self._node.error.code : 0);
// Clear the event listener.
self._node.removeEventListener('error', self._errorListener, false);
},
/**
* HTML5 Audio canplaythrough listener callback.
*/
_loadListener: function() {
var self = this;
var parent = self._parent;
// Round up the duration to account for the lower precision in HTML5 Audio.
parent._duration = Math.ceil(self._node.duration * 10) / 10;
// Setup a sprite if none is defined.
if (Object.keys(parent._sprite).length === 0) {
parent._sprite = {__default: [0, parent._duration * 1000]};
}
if (!parent._loaded) {
parent._loaded = true;
parent._emit('load');
}
if (parent._autoplay) {
parent.play();
}
// Clear the event listener.
self._node.removeEventListener('canplaythrough', self._loadListener, false);
}
};
/** Helper Methods **/
/***************************************************************************/
// Only define these methods when using Web Audio.
if (usingWebAudio) {
var cache = {};
/**
* Buffer a sound from URL, Data URI or cache and decode to audio source (Web Audio API).
* @param {Howl} self
*/
var loadBuffer = function(self) {
var url = self._src;
// Check if the buffer has already been cached and use it instead.
if (cache[url]) {
// Set the duration from the cache.
self._duration = cache[url].duration;
// Load the sound into this Howl.
loadSound(self);
return;
}
if (/^data:[^;]+;base64,/.test(url)) {
// Decode the base64 data URI without XHR, since some browsers don't support it.
var data = atob(url.split(',')[1]);
var dataView = new Uint8Array(data.length);
for (var i=0; i<data.length; ++i) {
dataView[i] = data.charCodeAt(i);
}
decodeAudioData(dataView.buffer, self);
} else {
// Load the buffer from the URL.
var xhr = new XMLHttpRequest();
xhr.open('GET', url, true);
xhr.responseType = 'arraybuffer';
xhr.onload = function() {
decodeAudioData(xhr.response, self);
};
xhr.onerror = function() {
// If there is an error, switch to HTML5 Audio.
if (self._webAudio) {
self._html5 = true;
self._webAudio = false;
self._sounds = [];
delete cache[url];
self.load();
}
};
safeXhrSend(xhr);
}
};
/**
* Send the XHR request wrapped in a try/catch.
* @param {Object} xhr XHR to send.
*/
var safeXhrSend = function(xhr) {
try {
xhr.send();
} catch (e) {
xhr.onerror();
}
};
/**
* Decode audio data from an array buffer.
* @param {ArrayBuffer} arraybuffer The audio data.
* @param {Howl} self
*/
var decodeAudioData = function(arraybuffer, self) {
// Decode the buffer into an audio source.
ctx.decodeAudioData(arraybuffer, function(buffer) {
if (buffer) {
cache[self._src] = buffer;
loadSound(self, buffer);
}
}, function() {
self._emit('loaderror');
});
};
/**
* Sound is now loaded, so finish setting everything up and fire the loaded event.
* @param {Howl} self
* @param {Object} buffer The decoded buffer sound source.
*/
var loadSound = function(self, buffer) {
// Set the duration.
if (buffer && !self._duration) {
self._duration = buffer.duration;
}
// Setup a sprite if none is defined.
if (Object.keys(self._sprite).length === 0) {
self._sprite = {__default: [0, self._duration * 1000]};
}
// Fire the loaded event.
if (!self._loaded) {
self._loaded = true;
self._emit('load');
}
// Begin playback if specified.
if (self._autoplay) {
self.play();
}
};
}
/**
* Setup the audio context when available, or switch to HTML5 Audio mode.
*/
function setupAudioContext() {
try {
if (typeof AudioContext !== 'undefined') {
ctx = new AudioContext();
} else if (typeof webkitAudioContext !== 'undefined') {
ctx = new webkitAudioContext();
} else {
usingWebAudio = false;
}
} catch(e) {
usingWebAudio = false;
}
if (!usingWebAudio) {
if (typeof Audio !== 'undefined') {
try {
new Audio();
} catch(e) {
noAudio = true;
}
} else {
noAudio = true;
}
}
}
// Add support for AMD (Asynchronous Module Definition) libraries such as require.js.
if (typeof define === 'function' && define.amd) {
define('howler', function() {
return {
Howler: Howler,
Howl: Howl
};
});
}
// Add support for CommonJS libraries such as browserify.
if (typeof exports !== 'undefined') {
exports.Howler = Howler;
exports.Howl = Howl;
}
// Define globally in case AMD is not available or unused.
if (typeof window !== 'undefined') {
window.HowlerGlobal = HowlerGlobal;
window.Howler = Howler;
window.Howl = Howl;
window.Sound = Sound;
}
})();