tone
Version:
A Web Audio framework for making interactive music in the browser.
259 lines • 9.62 kB
JavaScript
import { __decorate } from "tslib";
import { ToneAudioBuffers } from "../core/context/ToneAudioBuffers.js";
import { ftomf, intervalToFrequencyRatio } from "../core/type/Conversions.js";
import { FrequencyClass } from "../core/type/Frequency.js";
import { optionsFromArguments } from "../core/util/Defaults.js";
import { noOp } from "../core/util/Interface.js";
import { isArray, isNote, isNumber } from "../core/util/TypeCheck.js";
import { Instrument } from "../instrument/Instrument.js";
import { ToneBufferSource, } from "../source/buffer/ToneBufferSource.js";
import { timeRange } from "../core/util/Decorator.js";
import { assert } from "../core/util/Debug.js";
/**
* Pass in an object which maps the note's pitch or midi value to the url,
* then you can trigger the attack and release of that note like other instruments.
* By automatically repitching the samples, it is possible to play pitches which
* were not explicitly included which can save loading time.
*
* For sample or buffer playback where repitching is not necessary,
* use {@link Player}.
* @example
* const sampler = new Tone.Sampler({
* urls: {
* A1: "A1.mp3",
* A2: "A2.mp3",
* },
* baseUrl: "https://tonejs.github.io/audio/casio/",
* onload: () => {
* sampler.triggerAttackRelease(["C1", "E1", "G1", "B1"], 0.5);
* }
* }).toDestination();
* @category Instrument
*/
export class Sampler extends Instrument {
constructor() {
const options = optionsFromArguments(Sampler.getDefaults(), arguments, ["urls", "onload", "baseUrl"], "urls");
super(options);
this.name = "Sampler";
/**
* The object of all currently playing BufferSources
*/
this._activeSources = new Map();
const urlMap = {};
Object.keys(options.urls).forEach((note) => {
const noteNumber = parseInt(note, 10);
assert(isNote(note) || (isNumber(noteNumber) && isFinite(noteNumber)), `url key is neither a note or midi pitch: ${note}`);
if (isNote(note)) {
// convert the note name to MIDI
const mid = new FrequencyClass(this.context, note).toMidi();
urlMap[mid] = options.urls[note];
}
else if (isNumber(noteNumber) && isFinite(noteNumber)) {
// otherwise if it's numbers assume it's midi
urlMap[noteNumber] = options.urls[noteNumber];
}
});
this._buffers = new ToneAudioBuffers({
urls: urlMap,
onload: options.onload,
baseUrl: options.baseUrl,
onerror: options.onerror,
});
this.attack = options.attack;
this.release = options.release;
this.curve = options.curve;
// invoke the callback if it's already loaded
if (this._buffers.loaded) {
// invoke onload deferred
Promise.resolve().then(options.onload);
}
}
static getDefaults() {
return Object.assign(Instrument.getDefaults(), {
attack: 0,
baseUrl: "",
curve: "exponential",
onload: noOp,
onerror: noOp,
release: 0.1,
urls: {},
});
}
/**
* Returns the difference in steps between the given midi note at the closets sample.
*/
_findClosest(midi) {
// searches within 8 octaves of the given midi note
const MAX_INTERVAL = 96;
let interval = 0;
while (interval < MAX_INTERVAL) {
// check above and below
if (this._buffers.has(midi + interval)) {
return -interval;
}
else if (this._buffers.has(midi - interval)) {
return interval;
}
interval++;
}
throw new Error(`No available buffers for note: ${midi}`);
}
/**
* @param notes The note to play, or an array of notes.
* @param time When to play the note
* @param velocity The velocity to play the sample back.
*/
triggerAttack(notes, time, velocity = 1) {
this.log("triggerAttack", notes, time, velocity);
if (!Array.isArray(notes)) {
notes = [notes];
}
notes.forEach((note) => {
const midiFloat = ftomf(new FrequencyClass(this.context, note).toFrequency());
const midi = Math.round(midiFloat);
const remainder = midiFloat - midi;
// find the closest note pitch
const difference = this._findClosest(midi);
const closestNote = midi - difference;
const buffer = this._buffers.get(closestNote);
const playbackRate = intervalToFrequencyRatio(difference + remainder);
// play that note
const source = new ToneBufferSource({
url: buffer,
context: this.context,
curve: this.curve,
fadeIn: this.attack,
fadeOut: this.release,
playbackRate,
}).connect(this.output);
source.start(time, 0, buffer.duration / playbackRate, velocity);
// add it to the active sources
if (!isArray(this._activeSources.get(midi))) {
this._activeSources.set(midi, []);
}
this._activeSources.get(midi).push(source);
// remove it when it's done
source.onended = () => {
if (this._activeSources && this._activeSources.has(midi)) {
const sources = this._activeSources.get(midi);
const index = sources.indexOf(source);
if (index !== -1) {
sources.splice(index, 1);
}
}
};
});
return this;
}
/**
* @param notes The note to release, or an array of notes.
* @param time When to release the note.
*/
triggerRelease(notes, time) {
this.log("triggerRelease", notes, time);
if (!Array.isArray(notes)) {
notes = [notes];
}
notes.forEach((note) => {
const midi = new FrequencyClass(this.context, note).toMidi();
// find the note
if (this._activeSources.has(midi) &&
this._activeSources.get(midi).length) {
const sources = this._activeSources.get(midi);
time = this.toSeconds(time);
sources.forEach((source) => {
source.stop(time);
});
this._activeSources.set(midi, []);
}
});
return this;
}
/**
* Release all currently active notes.
* @param time When to release the notes.
*/
releaseAll(time) {
const computedTime = this.toSeconds(time);
this._activeSources.forEach((sources) => {
while (sources.length) {
const source = sources.shift();
source.stop(computedTime);
}
});
return this;
}
sync() {
if (this._syncState()) {
this._syncMethod("triggerAttack", 1);
this._syncMethod("triggerRelease", 1);
}
return this;
}
/**
* Invoke the attack phase, then after the duration, invoke the release.
* @param notes The note to play and release, or an array of notes.
* @param duration The time the note should be held
* @param time When to start the attack
* @param velocity The velocity of the attack
*/
triggerAttackRelease(notes, duration, time, velocity = 1) {
const computedTime = this.toSeconds(time);
this.triggerAttack(notes, computedTime, velocity);
if (isArray(duration)) {
assert(isArray(notes), "notes must be an array when duration is array");
notes.forEach((note, index) => {
const d = duration[Math.min(index, duration.length - 1)];
this.triggerRelease(note, computedTime + this.toSeconds(d));
});
}
else {
this.triggerRelease(notes, computedTime + this.toSeconds(duration));
}
return this;
}
/**
* Add a note to the sampler.
* @param note The buffer's pitch.
* @param url Either the url of the buffer, or a buffer which will be added with the given name.
* @param callback The callback to invoke when the url is loaded.
*/
add(note, url, callback) {
assert(isNote(note) || isFinite(note), `note must be a pitch or midi: ${note}`);
if (isNote(note)) {
// convert the note name to MIDI
const mid = new FrequencyClass(this.context, note).toMidi();
this._buffers.add(mid, url, callback);
}
else {
// otherwise if it's numbers assume it's midi
this._buffers.add(note, url, callback);
}
return this;
}
/**
* If the buffers are loaded or not
*/
get loaded() {
return this._buffers.loaded;
}
/**
* Clean up
*/
dispose() {
super.dispose();
this._buffers.dispose();
this._activeSources.forEach((sources) => {
sources.forEach((source) => source.dispose());
});
this._activeSources.clear();
return this;
}
}
__decorate([
timeRange(0)
], Sampler.prototype, "attack", void 0);
__decorate([
timeRange(0)
], Sampler.prototype, "release", void 0);
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