2020js13k/sound.js

class MusicNotes {
	constructor() {
		this.isMuted = false;
		//https://gist.github.com/marcgg/94e97def0e8694f906443ed5262e9cbb
		this.frequencyLookup = {
			'C0': 16.35,
			'C#0': 17.32,
			'Db0': 17.32,
			'D0': 18.35,
			'D#0': 19.45,
			'Eb0': 19.45,
			'E0': 20.60,
			'F0': 21.83,
			'F#0': 23.12,
			'Gb0': 23.12,
			'G0': 24.50,
			'G#0': 25.96,
			'Ab0': 25.96,
			'A0': 27.50,
			'A#0': 29.14,
			'Bb0': 29.14,
			'B0': 30.87,
			'C1': 32.70,
			'C#1': 34.65,
			'Db1': 34.65,
			'D1': 36.71,
			'D#1': 38.89,
			'Eb1': 38.89,
			'E1': 41.20,
			'F1': 43.65,
			'F#1': 46.25,
			'Gb1': 46.25,
			'G1': 49.00,
			'G#1': 51.91,
			'Ab1': 51.91,
			'A1': 55.00,
			'A#1': 58.27,
			'Bb1': 58.27,
			'B1': 61.74,
			'C2': 65.41,
			'C#2': 69.30,
			'Db2': 69.30,
			'D2': 73.42,
			'D#2': 77.78,
			'Eb2': 77.78,
			'E2': 82.41,
			'F2': 87.31,
			'F#2': 92.50,
			'Gb2': 92.50,
			'G2': 98.00,
			'G#2': 103.83,
			'Ab2': 103.83,
			'A2': 110.00,
			'A#2': 116.54,
			'Bb2': 116.54,
			'B2': 123.47,
			'C3': 130.81,
			'C#3': 138.59,
			'Db3': 138.59,
			'D3': 146.83,
			'D#3': 155.56,
			'Eb3': 155.56,
			'E3': 164.81,
			'F3': 174.61,
			'F#3': 185.00,
			'Gb3': 185.00,
			'G3': 196.00,
			'G#3': 207.65,
			'Ab3': 207.65,
			'A3': 220.00,
			'A#3': 233.08,
			'Bb3': 233.08,
			'B3': 246.94,
			'C4': 261.63,
			'C#4': 277.18,
			'Db4': 277.18,
			'D4': 293.66,
			'D#4': 311.13,
			'Eb4': 311.13,
			'E4': 329.63,
			'F4': 349.23,
			'F#4': 369.99,
			'Gb4': 369.99,
			'G4': 392.00,
			'G#4': 415.30,
			'Ab4': 415.30,
			'A4': 440.00,
			'A#4': 466.16,
			'Bb4': 466.16,
			'B4': 493.88,
			'C5': 523.25,
			'C#5': 554.37,
			'Db5': 554.37,
			'D5': 587.33,
			'D#5': 622.25,
			'Eb5': 622.25,
			'E5': 659.26,
			'F5': 698.46,
			'F#5': 739.99,
			'Gb5': 739.99,
			'G5': 783.99,
			'G#5': 830.61,
			'Ab5': 830.61,
			'A5': 880.00,
			'A#5': 932.33,
			'Bb5': 932.33,
			'B5': 987.77,
			'C6': 1046.50,
			'C#6': 1108.73,
			'Db6': 1108.73,
			'D6': 1174.66,
			'D#6': 1244.51,
			'Eb6': 1244.51,
			'E6': 1318.51,
			'F6': 1396.91,
			'F#6': 1479.98,
			'Gb6': 1479.98,
			'G6': 1567.98,
			'G#6': 1661.22,
			'Ab6': 1661.22,
			'A6': 1760.00,
			'A#6': 1864.66,
			'Bb6': 1864.66,
			'B6': 1975.53,
			'C7': 2093.00,
			'C#7': 2217.46,
			'Db7': 2217.46,
			'D7': 2349.32,
			'D#7': 2489.02,
			'Eb7': 2489.02,
			'E7': 2637.02,
			'F7': 2793.83,
			'F#7': 2959.96,
			'Gb7': 2959.96,
			'G7': 3135.96,
			'G#7': 3322.44,
			'Ab7': 3322.44,
			'A7': 3520.00,
			'A#7': 3729.31,
			'Bb7': 3729.31,
			'B7': 3951.07,
			'C8': 4186.01
		}
		this.audioContext = new (window.AudioContext || window.webkitAudioContext)({
			latencyHint: "interactive",
			sampleRate: 48000
		});
		this.volume = 75;
	}

	playPing(note, start = 0, notelength = 0.5) {
		if (this.isMuted) {
			return;
		}
		let buffer = this.audioContext.createBuffer(2, this.audioContext.sampleRate * 3, this.audioContext.sampleRate);

		let oscillatorNode = this.audioContext.createOscillator();
		oscillatorNode.buffer = buffer;
		oscillatorNode.type = "sine";
		oscillatorNode.frequency.value = this.frequencyLookup[note];

		let gainNode = this.audioContext.createGain();
		gainNode.gain.setValueAtTime(this.volume / 100, this.audioContext.currentTime + start);
		oscillatorNode.connect(gainNode);
		gainNode.connect(this.audioContext.destination);

		oscillatorNode.start(this.audioContext.currentTime + start);

		gainNode.gain.exponentialRampToValueAtTime(0.00001, this.audioContext.currentTime + start + notelength);
		oscillatorNode.stop(this.audioContext.currentTime + start + notelength);
	}

	playPingSequence(sequence, between, notelength = 0.5) {
		let delay = 0;
		for (let i = 0; i < sequence.length; i++) {
			this.playPing(sequence[i], delay, notelength);
			delay += (between / 1000);
		}
	}
}