clocksync/index.html at master · ffdead/clocksync · GitHub

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<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Example usage of clocksync.js</title>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script src="libs/buffer-loader.js"></script>
<script src="libs/raf.js"></script>
<script src="clocksync.js"></script>
<script>

</script>
<style>
	html, body {
		font-family: Helvetica, sans serif;
		font-size: 2em;
		height: 100%;
		background: #eee;
	}
</style>
</head>
<body>

	<div id="clock"></a>

	<script>
		var $clock = $('#clock');

		var context = new webkitAudioContext();
		var bufferLoader;
		var bufferList;

		function initsounds() {
			bufferLoader = new BufferLoader(
				context,
				[
					'sounds/Kick.mp3',
					'sounds/beep.mp3'
				],
				function (b) {
					bufferList = b;
				}
			);
			bufferLoader.load();
		};

		var beep = function (time) {
			if (!bufferList) {
				return;
			}

			var source1 = context.createBufferSource();
			source1.buffer = bufferList[1];
			source1.connect(context.destination);
			source1.noteOn(time);
		};


		var lastPlay = -1;

		// scheduling based on server time more stable on mobile (context time stops when app looses focus?)
		var scheduleSound = function (serverTime) {
			nowMs = serverTime * .001;
			ctxTime = context.currentTime;
			nextSecond = Math.ceil(nowMs);

			if (nextSecond > lastPlay) {
				lastPlay = nextSecond
				msToNextS = nextSecond - nowMs;
				var time = ctxTime + msToNextS;
				beep(time);
			}
		};

		// schedule based on audiocontext time
		/*
		var scheduleSound = function (serverTime) {
			currentTime = context.currentTime;
			if (lastPlay === -1) {
				// schedule first play based on server time
				nowMs = serverTime * .001;
				nextSecond = Math.ceil(nowMs);
				msToNextS = nextSecond - nowMs;
				nextTime = currentTime + msToNextS;
			}
			else {
				nextTime = lastPlay + 1;
			}

			if (currentTime > lastPlay) {
				lastPlay = nextTime;
				beep(nextTime);
			}
		};
		*/

		var runLoop = function () {
			window.requestAnimationFrame(runLoop);
			var time = clocksync.time();
			scheduleSound(time);
			$clock.text(time);
		}


		$('body').on('touchstart', function () {
			context.createBufferSource().noteOn(0);
			//lastPlay = -1;
		});

		initsounds();

		// setup a sync method using ajax
		clocksync.syncMethod = function () {
			$.post('/sync', clocksync.data(), clocksync.syncResponse, 'text');
		}

		// start synching
		clocksync.sync(function (now, delta) {
			console.log('obtained synched time:', now, ' local delta: ', delta);
			window.requestAnimationFrame(runLoop);
		});
	</script>

</body>
</html>