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clock.mjs
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clock.mjs
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/**
* a port of the THREE.Clock class
* https://github.com/mrdoob/three.js/blob/dev/src/core/Clock.js
*/
export default class Clock {
constructor(autoStart = true) {
this.startTime = 0;
this.oldTime = 0;
this._elapsedTime = 0;
this.autoStart = autoStart;
this.running = autoStart;
}
getDelta() {
const { running, autoStart } = this;
if (autoStart && !running) {
this.start();
return 0;
}
if (running) {
const newTime = (typeof performance === 'undefined' ? Date : performance).now();
const diff = (newTime - this.oldTime) / 1000;
this.oldTime = newTime;
this._elapsedTime += diff;
return diff;
}
return 0;
}
get elapsedTime() {
this.getDelta();
return this._elapsedTime;
}
start() {
this.startTime = (typeof performance === 'undefined' ? Date : performance).now();
this.oldTime = this.startTime;
this.running = true;
this._elapsedTime = 0;
}
stop() {
this.getDelta();
this.running = false;
this.autoStart = false;
}
}