110 lines
2.2 KiB
JavaScript
110 lines
2.2 KiB
JavaScript
import { requestAnimationFrame, cancelAnimationFrame } from "./../helpers/feature.mjs";
|
|
/**
|
|
* @class Interval
|
|
*/
|
|
class Interval {
|
|
static create(func, delay) {
|
|
return new Interval(func, delay);
|
|
}
|
|
constructor(func, delay) {
|
|
/**
|
|
* Animation frame request id.
|
|
*
|
|
* @type {number}
|
|
*/
|
|
this.timer = null;
|
|
/**
|
|
* Function to invoke repeatedly.
|
|
*
|
|
* @type {Function}
|
|
*/
|
|
this.func = func;
|
|
/**
|
|
* Number of milliseconds that function should wait before next call.
|
|
*/
|
|
this.delay = parseDelay(delay);
|
|
/**
|
|
* Flag which indicates if interval object was stopped.
|
|
*
|
|
* @type {boolean}
|
|
* @default true
|
|
*/
|
|
this.stopped = true;
|
|
/**
|
|
* Interval time (in milliseconds) of the last callback call.
|
|
*
|
|
* @private
|
|
* @type {number}
|
|
*/
|
|
this._then = null;
|
|
/**
|
|
* Bounded function `func`.
|
|
*
|
|
* @private
|
|
* @type {Function}
|
|
*/
|
|
this._callback = () => this.__callback();
|
|
}
|
|
|
|
/**
|
|
* Start loop.
|
|
*
|
|
* @returns {Interval}
|
|
*/
|
|
start() {
|
|
if (this.stopped) {
|
|
this._then = Date.now();
|
|
this.stopped = false;
|
|
this.timer = requestAnimationFrame(this._callback);
|
|
}
|
|
return this;
|
|
}
|
|
|
|
/**
|
|
* Stop looping.
|
|
*
|
|
* @returns {Interval}
|
|
*/
|
|
stop() {
|
|
if (!this.stopped) {
|
|
this.stopped = true;
|
|
cancelAnimationFrame(this.timer);
|
|
this.timer = null;
|
|
}
|
|
return this;
|
|
}
|
|
|
|
/**
|
|
* Loop callback, fired on every animation frame.
|
|
*
|
|
* @private
|
|
*/
|
|
__callback() {
|
|
this.timer = requestAnimationFrame(this._callback);
|
|
if (this.delay) {
|
|
const now = Date.now();
|
|
const elapsed = now - this._then;
|
|
if (elapsed > this.delay) {
|
|
this._then = now - elapsed % this.delay;
|
|
this.func();
|
|
}
|
|
} else {
|
|
this.func();
|
|
}
|
|
}
|
|
}
|
|
export default Interval;
|
|
|
|
/**
|
|
* Convert delay from string format to milliseconds.
|
|
*
|
|
* @param {number|string} delay The delay in FPS (frame per second) or number format.
|
|
* @returns {number}
|
|
*/
|
|
export function parseDelay(delay) {
|
|
let result = delay;
|
|
if (typeof result === 'string' && /fps$/.test(result)) {
|
|
result = 1000 / parseInt(result.replace('fps', '') || 0, 10);
|
|
}
|
|
return result;
|
|
} |