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import { Note, toCents } from './scale.mjs';
import GuitarFuzz from './vend/guitar-fuzz.mjs';
import Trombone from './vend/trombone.mjs';
const audioCtx = new AudioContext();
const fuzzWave = new PeriodicWave(audioCtx, {
real: GuitarFuzz.real,
imag: GuitarFuzz.imag
});
const tromboneWave = new PeriodicWave(audioCtx, {
real: Trombone.real,
imag: Trombone.imag
});
const globalGain = new GainNode(audioCtx, { gain: 0.06 })
export default class {
// oscillatornodes
notes = [];
// offsets is an array of offsets in cents from A4.
constructor(offsets) {
console.debug('Player#constructor', this, offsets);
this.offsets = offsets;
this.notes = offsets.map(o =>
new OscillatorNode(audioCtx, {
frequency: 440, // a above middle c (c4)
detune: o,
// type: 'sine',
type: 'custom',
periodicWave: tromboneWave,
}));
this.notes.forEach(n => n.connect(globalGain).connect(audioCtx.destination));
}
start() {
console.debug('Player#start', this);
this.notes.forEach(n => n.start());
}
stop() {
console.debug('Player#stop', this);
this.notes.forEach(n => n.stop());
}
test() {
const cNote = Note.fromString('C');
console.assert(cNote.distanceTo(cNote) === 0);
const dNote = Note.fromString('D');
console.assert(cNote.distanceTo(dNote) === 2);
const dSharpNote = Note.fromString('D♯');
console.assert(cNote.distanceTo(dSharpNote) === 3);
const aNote = Note.fromString('A', 'A to A');
console.assert(toCents([aNote, 4], [aNote, 3]) === -1200);
const bNote = Note.fromString('B');
console.assert(toCents([aNote, 4], [bNote, 4]) == 200, 'A4 to B4 is 200 cents');
// E F F# G G# A
const eNote = Note.fromString('E');
console.assert(toCents([aNote, 4], [eNote, 4]) === -500, 'E4 is 500 cents lower than A4');
console.assert(toCents([aNote, 4], [bNote, 3]) === -1000, 'A4 to B3 is 100 cents above -1200');
}
}
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