Tone.js/Tone/source/oscillator/Oscillator.ts
2019-08-13 18:35:07 -04:00

498 lines
14 KiB
TypeScript

import { AudioRange, Cents, Degrees, Frequency, Radians, Time } from "../../core/type/Units";
import { deepEquals, optionsFromArguments } from "../../core/util/Defaults";
import { readOnly } from "../../core/util/Interface";
import { isDefined } from "../../core/util/TypeCheck";
import { Signal } from "../../signal/Signal";
import { Source } from "../Source";
import { ToneOscillatorConstructorOptions, ToneOscillatorInterface,
ToneOscillatorOptions, ToneOscillatorType } from "./OscillatorInterface";
import { ToneOscillatorNode } from "./OscillatorNode";
/**
* Oscillator supports a number of features including
* phase rotation, multiple oscillator types (see Oscillator.type),
* and Transport syncing (see Oscillator.syncFrequency).
*
* @param frequency Starting frequency
* @param type The oscillator type. Read more about type below.
* @example
* //make and start a 440hz sine tone
* var osc = new Oscillator(440, "sine").toDestination().start();
*/
export class Oscillator extends Source<ToneOscillatorOptions> implements ToneOscillatorInterface {
name = "Oscillator";
/**
* the main oscillator
*/
private _oscillator: ToneOscillatorNode | null = null;
/**
* The frequency control.
*/
frequency: Signal<Frequency>;
/**
* The detune control signal.
*/
detune: Signal<Cents>;
/**
* the periodic wave
*/
private _wave?: PeriodicWave;
/**
* The partials of the oscillator
*/
private _partials: number[];
/**
* The number of partials to limit or extend the periodic wave by
*/
private _partialCount: number;
/**
* the phase of the oscillator between 0 - 360
*/
private _phase!: Radians;
/**
* the type of the oscillator
* @type {string}
* @private
*/
private _type;
constructor(options?: Partial<ToneOscillatorConstructorOptions>)
constructor(frequency?: Frequency, type?: ToneOscillatorType);
constructor() {
super(optionsFromArguments(Oscillator.getDefaults(), arguments, ["frequency", "type"]));
const options = optionsFromArguments(Oscillator.getDefaults(), arguments, ["frequency", "type"]);
this.frequency = new Signal<Frequency>({
context: this.context,
units: "frequency",
value: options.frequency,
});
readOnly(this, "frequency");
this.detune = new Signal<Cents>({
context: this.context,
units: "cents",
value: options.detune,
});
readOnly(this, "detune");
this._partials = options.partials;
this._partialCount = options.partialCount;
this._type = options.type;
if (options.partialCount && options.type !== "custom") {
this._type = this.baseType + options.partialCount.toString();
}
this.phase = options.phase;
}
static getDefaults(): ToneOscillatorOptions {
return Object.assign(Source.getDefaults(), {
detune: 0,
frequency: 440,
partialCount: 0,
partials: [],
phase: 0,
type: "sine",
}) as ToneOscillatorOptions;
}
/**
* start the oscillator
*/
protected _start(time?: Time): void {
this.log("start", time);
// new oscillator with previous values
const oscillator = new ToneOscillatorNode({
context: this.context,
onended: () => this.onstop(this),
});
this._oscillator = oscillator;
if (this._wave) {
this._oscillator.setPeriodicWave(this._wave);
} else {
this._oscillator.type = this._type;
}
// connect the control signal to the oscillator frequency & detune
this._oscillator.connect(this.output);
this.frequency.connect(this._oscillator.frequency);
this.detune.connect(this._oscillator.detune);
// start the oscillator
time = this.toSeconds(time);
this._oscillator.start(time);
}
/**
* stop the oscillator
*/
protected _stop(time?: Time): void {
const computedTime = this.toSeconds(time);
this.log("stop", computedTime);
if (this._oscillator) {
time = this.toSeconds(time);
this._oscillator.stop(time);
}
}
/**
* Restart the oscillator. Does not stop the oscillator, but instead
* just cancels any scheduled 'stop' from being invoked.
*/
restart(time?: Time): this {
if (this._oscillator) {
this._oscillator.cancelStop();
}
this._state.cancel(this.toSeconds(time));
return this;
}
/**
* Sync the signal to the Transport's bpm. Any changes to the transports bpm,
* will also affect the oscillators frequency.
* @example
* Tone.Transport.bpm.value = 120;
* osc.frequency.value = 440;
* //the ration between the bpm and the frequency will be maintained
* osc.syncFrequency();
* Tone.Transport.bpm.value = 240;
* // the frequency of the oscillator is doubled to 880
*/
syncFrequency(): this {
this.context.transport.syncSignal(this.frequency);
return this;
}
/**
* Unsync the oscillator's frequency from the Transport.
* See Oscillator.syncFrequency
*/
unsyncFrequency(): this {
this.context.transport.unsyncSignal(this.frequency);
return this;
}
/**
* Cache the periodic waves to avoid having to redo computations
*/
private static _periodicWaveCache: Array<{
partials: number[];
phase: number;
type: string;
partialCount: number;
real: Float32Array,
imag: Float32Array,
}> = [];
/**
* Get a cached periodic wave. Avoids having to recompute
* the oscillator values when they have already been computed
* with the same values.
*/
private _getCachedPeriodicWave(): [Float32Array, Float32Array] | undefined {
if (this._type === "custom") {
const oscProps = Oscillator._periodicWaveCache.find(description => {
return description.phase === this._phase &&
deepEquals(description.partials, this._partials);
});
return oscProps && [oscProps.real, oscProps.imag];
} else {
const oscProps = Oscillator._periodicWaveCache.find(description => {
return description.type === this._type &&
description.phase === this._phase;
});
this._partialCount = oscProps ? oscProps.partialCount : this._partialCount;
return oscProps && [oscProps.real, oscProps.imag];
}
}
/* tslint:disable */
/**
* The type of the oscillator: either sine, square, triangle, or sawtooth. Also capable of
* setting the first x number of partials of the oscillator. For example: "sine4" would
* set be the first 4 partials of the sine wave and "triangle8" would set the first
* 8 partials of the triangle wave.
* <br><br>
* Uses PeriodicWave internally even for native types so that it can set the phase.
* PeriodicWave equations are from the
* [Webkit Web Audio implementation](https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit/Source/modules/webaudio/PeriodicWave.cpp&sq=package:chromium).
*
* @memberOf Oscillator#
* @type {string}
* @name type
* @example
* //set it to a square wave
* osc.type = "square";
* @example
* //set the first 6 partials of a sawtooth wave
* osc.type = "sawtooth6";
*/
/* tslint:enable */
get type(): ToneOscillatorType {
return this._type;
}
set type(type: ToneOscillatorType) {
this._type = type;
const isBasicType = ["sine", "square", "sawtooth", "triangle"].indexOf(type) !== -1;
if (this._phase === 0 && isBasicType) {
this._wave = undefined;
this._partialCount = 0;
// just go with the basic approach
if (this._oscillator !== null) {
// already tested that it's a basic type
this._oscillator.type = type as OscillatorType;
}
} else {
// first check if the value is cached
const cache = this._getCachedPeriodicWave();
if (isDefined(cache)) {
const [real, imag] = cache;
this._wave = this.context.createPeriodicWave(real, imag);
if (this._oscillator !== null) {
this._oscillator.setPeriodicWave(this._wave);
}
} else {
const [real, imag] = this._getRealImaginary(type, this._phase);
const periodicWave = this.context.createPeriodicWave(real, imag);
this._wave = periodicWave;
if (this._oscillator !== null) {
this._oscillator.setPeriodicWave(this._wave);
}
// set the cache
Oscillator._periodicWaveCache.push({
imag,
partialCount: this._partialCount,
partials: this._partials,
phase: this._phase,
real,
type: this._type,
});
if (Oscillator._periodicWaveCache.length > 100) {
Oscillator._periodicWaveCache.shift();
}
}
}
}
/**
* The oscillator type without the partialsCount appended to the end
* @example
* osc.type = 'sine2'
* osc.baseType //'sine'
* osc.partialCount = 2
*/
get baseType(): OscillatorType {
return this._type.replace(this.partialCount, "");
}
set baseType(baseType: OscillatorType) {
if (this.partialCount && this._type !== "custom" && baseType !== "custom") {
this.type = baseType + this.partialCount as ToneOscillatorType;
} else {
this.type = baseType;
}
}
/**
* 'partialCount' offers an alternative way to set the number of used partials.
* When partialCount is 0, the maximum number of partials are used when representing
* the waveform using the periodicWave. When 'partials' is set, this value is
* not settable, but equals the length of the partials array.
* @example
* osc.type = 'sine'
* osc.partialCount = 3
* //is equivalent to
* osc.type = 'sine3'
*/
get partialCount(): number {
return this._partialCount;
}
set partialCount(p: number) {
let type = this._type;
const partial = /^(sine|triangle|square|sawtooth)(\d+)$/.exec(this._type);
if (partial) {
type = partial[1];
}
if (this._type !== "custom") {
if (p === 0) {
this.type = type;
} else {
this.type = type + p.toString() as ToneOscillatorType;
}
}
}
/**
* Get the object's attributes. Given no arguments get
* will return all available object properties and their corresponding
* values.
*/
get(): ToneOscillatorOptions {
const values = super.get();
if (values.type !== "custom") {
delete values.partials;
}
return values;
}
/**
* Returns the real and imaginary components based
* on the oscillator type.
* @returns [real: Float32Array, imaginary: Float32Array]
* @private
*/
private _getRealImaginary(type: ToneOscillatorType, phase: Radians): Float32Array[] {
const fftSize = 4096;
let periodicWaveSize = fftSize / 2;
const real = new Float32Array(periodicWaveSize);
const imag = new Float32Array(periodicWaveSize);
let partialCount = 1;
if (type === "custom") {
partialCount = this._partials.length + 1;
this._partialCount = this._partials.length;
periodicWaveSize = partialCount;
// if the partial count is 0, don't bother doing any computation
if (this._partials.length === 0 ) {
return [real, imag];
}
} else {
const partial = /^(sine|triangle|square|sawtooth)(\d+)$/.exec(type);
if (partial) {
partialCount = parseInt(partial[2], 10) + 1;
this._partialCount = parseInt(partial[2], 10);
type = partial[1] as ToneOscillatorType;
partialCount = Math.max(partialCount, 2);
periodicWaveSize = partialCount;
} else {
this._partialCount = 0;
}
this._partials = [];
}
// tslint:disable: no-bitwise
for (let n = 1; n < periodicWaveSize; ++n) {
const piFactor = 2 / (n * Math.PI);
let b;
switch (type) {
case "sine":
b = (n <= partialCount) ? 1 : 0;
this._partials[n - 1] = b;
break;
case "square":
b = (n & 1) ? 2 * piFactor : 0;
this._partials[n - 1] = b;
break;
case "sawtooth":
b = piFactor * ((n & 1) ? 1 : -1);
this._partials[n - 1] = b;
break;
case "triangle":
if (n & 1) {
b = 2 * (piFactor * piFactor) * ((((n - 1) >> 1) & 1) ? -1 : 1);
} else {
b = 0;
}
this._partials[n - 1] = b;
break;
case "custom":
b = this._partials[n - 1];
break;
default:
throw new TypeError("Oscillator: invalid type: " + type);
}
if (b !== 0) {
real[n] = -b * Math.sin(phase * n);
imag[n] = b * Math.cos(phase * n);
} else {
real[n] = 0;
imag[n] = 0;
}
}
return [real, imag];
}
/**
* Compute the inverse FFT for a given phase.
*/
private _inverseFFT(real: Float32Array, imag: Float32Array, phase: Radians): number {
let sum = 0;
const len = real.length;
for (let i = 0; i < len; i++) {
sum += real[i] * Math.cos(i * phase) + imag[i] * Math.sin(i * phase);
}
return sum;
}
/**
* Returns the initial value of the oscillator.
*/
protected _getInitialValue(): AudioRange {
const [real, imag] = this._getRealImaginary(this._type, 0);
let maxValue = 0;
const twoPi = Math.PI * 2;
// check for peaks in 8 places
for (let i = 0; i < 8; i++) {
maxValue = Math.max(this._inverseFFT(real, imag, (i / 8) * twoPi), maxValue);
}
return -this._inverseFFT(real, imag, this._phase) / maxValue;
}
/**
* The partials of the waveform. A partial represents
* the amplitude at a harmonic. The first harmonic is the
* fundamental frequency, the second is the octave and so on
* following the harmonic series.
* Setting this value will automatically set the type to "custom".
* The value is an empty array when the type is not "custom".
* @example
* osc.partials = [1, 0.2, 0.01];
*/
get partials(): number[] {
return this._partials;
}
set partials(partials: number[]) {
this._partials = partials;
if (partials.length) {
this.type = "custom";
}
}
/**
* The phase of the oscillator in degrees.
* @example
* osc.phase = 180; //flips the phase of the oscillator
*/
get phase(): Degrees {
return this._phase * (180 / Math.PI);
}
set phase(phase: Degrees) {
this._phase = phase * Math.PI / 180;
// reset the type
this.type = this._type;
}
/**
* Dispose and disconnect.
*/
dispose(): this {
super.dispose();
if (this._oscillator !== null) {
this._oscillator.dispose();
}
this._wave = undefined;
this.frequency.dispose();
this.detune.dispose();
return this;
}
}