I'm using HTML5 to program games; the obstacle I've run into now is how to play sound effects.
The specific requirements are few in number:
My first approach was to use the HTML5 <audio>
element and define all sound effects in my page. Firefox plays the WAV files just peachy, but calling #play
multiple times doesn't really play the sample multiple times. From my understanding of the HTML5 spec, the <audio>
element also tracks playback state, so that explains why.
My immediate thought was to clone the audio elements, so I created the following tiny JavaScript library to do that for me (depends on jQuery):
var Snd = {
init: function() {
$("audio").each(function() {
var src = this.getAttribute('src');
if (src.substring(0, 4) !== "snd/") { return; }
// Cut out the basename (strip directory and extension)
var name = src.substring(4, src.length - 4);
// Create the helper function, which clones the audio object and plays it
var Constructor = function() {};
Constructor.prototype = this;
Snd[name] = function() {
var clone = new Constructor();
clone.play();
// Return the cloned element, so the caller can interrupt the sound effect
return clone;
};
});
}
};
So now I can do Snd.boom();
from the Firebug console and play snd/boom.wav
, but I still can't play the same sample multiple times. It seems that the <audio>
element is really more of a streaming feature rather than something to play sound effects with.
Is there a clever way to make this happen that I'm missing, preferably using only HTML5 and JavaScript?
I should also mention that, my test environment is Firefox 3.5 on Ubuntu 9.10. The other browsers I've tried - Opera, Midori, Chromium, Epiphany - produced varying results. Some don't play anything, and some throw exceptions.
Audio
objectsYou don't need to bother with <audio>
elements. HTML 5 lets you access Audio
objects directly:
var snd = new Audio("file.wav"); // buffers automatically when created
snd.play();
There's no support for mixing in current version of the spec.
To play same sound multiple times, create multiple instances of the Audio
object. You could also set snd.currentTime=0
on the object after it finishes playing.
Since the JS constructor doesn't support fallback <source>
elements, you should use
(new Audio()).canPlayType("audio/ogg; codecs=vorbis")
to test whether the browser supports Ogg Vorbis.
If you're writing a game or a music app (more than just a player), you'll want to use more advanced Web Audio API, which is now supported by most browsers.