cryptalk/public/js/lib/audio.js

88 lines
2.1 KiB
JavaScript

/* Usage:
mediator.on('audio:play', playTones );
mediator.on('audio:on', on );
mediator.on('audio:off', off );
mediator.on('audio:mute', mute );
mediator.on('audio:unmute', unmute );
*/
// Sounds module, used for emitting those annoying bl-up sounds when receiving a message
define(['queue','castrato','templates'], function (queue,mediator,templates) {
var
// Private variables
ac = false,
enabled = true,
muted = false,
// Recursive function for playing tones
// accepts an array of [tone,start_ms,duration_ms] - entries
playTones = function (tones, i) {
// Parameter defaults
i = (i === undefined) ? 0 : i;
// Stop if we've reached the end of iteration, and require ac, also stop if we're muted
if (!ac || !enabled || !(i < Object.keys(tones).length) || muted) {
return;
}
// Add tones to execution queue
var current_tones = tones[i],
freqs = current_tones[0],
start = current_tones[1],
duration = current_tones[2];
var o = ac.createOscillator();
var g = ac.createGain();
o.frequency.value = freqs;
o.connect(g);
g.gain.value = 0.25;
g.connect(ac.destination);
queue.add_function_delayed(start,function() { o.noteOn ? o.noteOn(0) : o.start(0); });
queue.add_function_delayed(start+duration,function() { o.noteOff ? o.noteOff(0) : o.stop(0); });
// Iterate, or start playing
i++;
if( i < Object.keys(tones).length ) {
playTones(tones,i);
} else {
queue.run();
}
},
on = function() {
enabled = true;
},
off = function() {
enabled = false;
},
mute = function() {
muted = true;
mediator.emit('console:info',templates.messages.muted);
},
unmute = function() {
muted = false;
mediator.emit('console:info',templates.messages.unmuted);
};
// Find audio context
if (window.AudioContext || window.webkitAudioContext) {
ac = new (window.AudioContext || window.webkitAudioContext);
}
// Connect events
mediator.on('audio:play', function(tones) {playTones(tones); } );
mediator.on('audio:on', on );
mediator.on('audio:off', off );
mediator.on('audio:mute', mute );
mediator.on('audio:unmute', unmute );
});