mirror of
https://github.com/Tonejs/Tone.js
synced 2024-11-15 08:17:07 +00:00
f17249691d
now in the form Tone.Something instead of using `import { Something } from "tone"`. It makes the example runner on the docs page work much faster
121 lines
3.2 KiB
TypeScript
121 lines
3.2 KiB
TypeScript
import { Effect, EffectOptions } from "./Effect";
|
|
import { Positive } from "../core/type/Units";
|
|
import { optionsFromArguments } from "../core/util/Defaults";
|
|
import { WaveShaper } from "../signal/WaveShaper";
|
|
|
|
export interface ChebyshevOptions extends EffectOptions {
|
|
order: Positive;
|
|
oversample: OverSampleType;
|
|
}
|
|
|
|
/**
|
|
* Chebyshev is a waveshaper which is good
|
|
* for making different types of distortion sounds.
|
|
* Note that odd orders sound very different from even ones,
|
|
* and order = 1 is no change.
|
|
* Read more at [music.columbia.edu](http://music.columbia.edu/cmc/musicandcomputers/chapter4/04_06.php).
|
|
* @example
|
|
* // create a new cheby
|
|
* const cheby = new Tone.Chebyshev(50).toDestination();
|
|
* // create a monosynth connected to our cheby
|
|
* const synth = new Tone.MonoSynth().connect(cheby);
|
|
* synth.triggerAttackRelease("C2", 0.4);
|
|
* @category Effect
|
|
*/
|
|
export class Chebyshev extends Effect<ChebyshevOptions> {
|
|
|
|
readonly name: string = "Chebyshev";
|
|
|
|
/**
|
|
* The private waveshaper node
|
|
*/
|
|
private _shaper: WaveShaper;
|
|
|
|
/**
|
|
* holds onto the order of the filter
|
|
*/
|
|
private _order: number;
|
|
|
|
/**
|
|
* @param order The order of the chebyshev polynomial. Normal range between 1-100.
|
|
*/
|
|
constructor(order?: Positive);
|
|
constructor(options?: Partial<ChebyshevOptions>);
|
|
constructor() {
|
|
|
|
super(optionsFromArguments(Chebyshev.getDefaults(), arguments, ["order"]));
|
|
const options = optionsFromArguments(Chebyshev.getDefaults(), arguments, ["order"]);
|
|
|
|
this._shaper = new WaveShaper({
|
|
context: this.context,
|
|
length: 4096
|
|
});
|
|
this._order = options.order;
|
|
|
|
this.connectEffect(this._shaper);
|
|
this.order = options.order;
|
|
this.oversample = options.oversample;
|
|
}
|
|
|
|
static getDefaults(): ChebyshevOptions {
|
|
return Object.assign(Effect.getDefaults(), {
|
|
order: 1,
|
|
oversample: "none" as "none"
|
|
});
|
|
}
|
|
|
|
/**
|
|
* get the coefficient for that degree
|
|
* @param x the x value
|
|
* @param degree
|
|
* @param memo memoize the computed value. this speeds up computation greatly.
|
|
*/
|
|
private _getCoefficient(x: number, degree: number, memo: Map<number, number>): number {
|
|
if (memo.has(degree)) {
|
|
return memo.get(degree) as number;
|
|
} else if (degree === 0) {
|
|
memo.set(degree, 0);
|
|
} else if (degree === 1) {
|
|
memo.set(degree, x);
|
|
} else {
|
|
memo.set(degree, 2 * x * this._getCoefficient(x, degree - 1, memo) - this._getCoefficient(x, degree - 2, memo));
|
|
}
|
|
return memo.get(degree) as number;
|
|
}
|
|
|
|
/**
|
|
* The order of the Chebyshev polynomial which creates the equation which is applied to the incoming
|
|
* signal through a Tone.WaveShaper. The equations are in the form:
|
|
* ```
|
|
* order 2: 2x^2 + 1
|
|
* order 3: 4x^3 + 3x
|
|
* ```
|
|
* @min 1
|
|
* @max 100
|
|
*/
|
|
get order(): Positive {
|
|
return this._order;
|
|
}
|
|
set order(order) {
|
|
this._order = order;
|
|
this._shaper.setMap((x => {
|
|
return this._getCoefficient(x, order, new Map());
|
|
}));
|
|
}
|
|
|
|
/**
|
|
* The oversampling of the effect. Can either be "none", "2x" or "4x".
|
|
*/
|
|
get oversample(): OverSampleType {
|
|
return this._shaper.oversample;
|
|
}
|
|
set oversample(oversampling) {
|
|
this._shaper.oversample = oversampling;
|
|
}
|
|
|
|
dispose(): this {
|
|
super.dispose();
|
|
this._shaper.dispose();
|
|
return this;
|
|
}
|
|
}
|