sandbox.html

<!DOCTYPE HTML>
<html>
	<head>
		<script src="synth.js"></script>
		<script src="audio.js"></script>
		<script src="gui.min.js"></script>
		<script>
			function makeGui() {
				var gui = new GUI();
				gui.add(TestProgram, 'waveform', 0, 1);
				gui.add(TestProgram, 'attackAmplitude', 0, 1);
				gui.add(TestProgram, 'sustainAmplitude', 0, 1);
				gui.add(TestProgram, 'attackTime', 0, 1);
				gui.add(TestProgram, 'decayTime', 0, 1);
				gui.add(TestProgram, 'releaseTime', 0, 1);
				gui.add(TestProgram, 'phase', 0, 1);
			}
			
			TestProgram = {
				'waveform': 0,
				'attackAmplitude': 0.2,
				'sustainAmplitude': 0.1,
				'attackTime': 0.02,
				'decayTime': 0.3,
				'releaseTime': 0.02,
				'phase': 0.5,
				'createNote': function(note, velocity) {
					var frequency = midiToFrequency(note);
					return ADSRGenerator(
						(this.waveform ? SquareGenerator(frequency, this.phase) : SineGenerator(frequency)),
						this.attackAmplitude * (velocity / 128), this.sustainAmplitude * (velocity / 128),
						this.attackTime, this.decayTime, this.releaseTime
					);
				}
			}
			
			function go(file) {
				synth = Synth(44100);
				var samplesToNextNote = 0;
				var currentGenerator = null;
				var noteNumber = 0;
				replayer = {
					'generate': function(samples) {
						var data = new Array(samples*2);
						var samplesRemaining = samples;
						var dataOffset = 0;
						
						while (samplesRemaining) {
							if (samplesToNextNote < samplesRemaining) {
								if (samplesToNextNote > 0) {
									synth.generateIntoBuffer(samplesToNextNote, data, dataOffset);
									dataOffset += samplesToNextNote * 2;
								}
								if (currentGenerator) {
									currentGenerator.noteOff();
								}
								currentGenerator = TestProgram.createNote(50 + noteNumber, 127);
								noteNumber = (noteNumber + 1) % 12;
								synth.addGenerator(currentGenerator);
								samplesRemaining -= samplesToNextNote;
								samplesToNextNote = 11025;
							} else {
								/* generate samplesRemaining */
								synth.generateIntoBuffer(samplesRemaining, data, dataOffset);
								samplesToNextNote -= samplesRemaining;
								samplesRemaining = 0;
							}
						}
						return data;
					}
				}
				audio = AudioPlayer(replayer, {'latency': 0.5});
			}
		</script>
	</head>
	<body onload="makeGui()">
		<a href="javascript:void(go())">go</a>
	</body>
</html>