<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
	<title>Signal Ramping</title>

	<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
	<link rel="icon" type="image/png" sizes="174x174" href="./favicon.png">

	<script src="https://cdnjs.cloudflare.com/ajax/libs/webcomponentsjs/2.4.3/webcomponents-bundle.js"></script>
	<link href="https://fonts.googleapis.com/css?family=Material+Icons&display=block" rel="stylesheet"/>
	<script src="../build/Tone.js"></script>
	<script src="./js/tone-ui.js"></script>
	<script src="./js/components.js"></script>
</head>
<body>
	<style>
		tone-slider {
			width: 100%;
			margin-top: 10px;
		}
	</style>
	<tone-example label="rampTo">
		<div slot="explanation">
			Working with signals is different than working with numbers or strings:
			Signals are values which are updated at audio rate,
			which allows for sample-accurate scheduling and ramping. <code>.rampTo(value, rampTime)</code>
			smoothly changes the signal from the current value to the target value over the duration of the rampTime.
			This example uses <code>.rampTo</code> in to smooth out changes in volume and frequency.
		</div>

		<div id="content">
			<tone-play-toggle></tone-play-toggle>
			<tone-slider label="harmonicity" min="0.5" max="2" value="1"></tone-slider>
		</div>
	</tone-example>

	<script type="text/javascript">
		const oscillators = [];

		const bassFreq = 32;

		for (let i = 0; i < 8; i++) {
			oscillators.push(new Tone.Oscillator({
				frequency: bassFreq * i,
				type: "sawtooth4",
				volume: -Infinity,
				detune: Math.random() * 30 - 15,
			}).toDestination());
		}

		// bind the interface
		document.querySelector("tone-play-toggle").addEventListener("start", e => {
			oscillators.forEach(o => {
				o.start();
				o.volume.rampTo(-20, 1);
			});
		});
		
		document.querySelector("tone-play-toggle").addEventListener("stop", e => {
			oscillators.forEach(o => {
				o.stop("+1.2");
				o.volume.rampTo(-Infinity, 1);
			});
		});

		document.querySelector("tone-slider").addEventListener("input", e => {
			oscillators.forEach((osc, i) => {
				osc.frequency.rampTo(bassFreq * i * parseFloat(e.target.value), 0.4);
			});
		});

	</script>
</body>
</html>