@thi.ng/dsp/impulse-train.js

Composable signal generators, oscillators, filters, FFT, spectrum, windowing & related DSP utils

import { AGen } from "./agen.js";
const impulseTrain = (period, start) => new ImpulseTrain(1, 0, period, start);
const impulseTrainT = (on, off, period, start) => new ImpulseTrain(on, off, period, start);
const impulseTrainB = (period, start) => new ImpulseTrain(true, false, period, start);
class ImpulseTrain extends AGen {
  constructor(_on, _off, _period, _pos = 0) {
    super(_off);
    this._on = _on;
    this._off = _off;
    this._period = _period;
    this._pos = _pos;
    this._startpos = --this._pos;
  }
  _startpos;
  copy() {
    return new ImpulseTrain(
      this._on,
      this._off,
      this._period,
      this._startpos + 1
    );
  }
  reset() {
    this._val = this._off;
    this._pos = this._startpos;
    return this;
  }
  next() {
    return this._val = ++this._pos >= this._period ? (this._pos = 0, this._on) : this._off;
  }
}
export {
  ImpulseTrain,
  impulseTrain,
  impulseTrainB,
  impulseTrainT
};