import EventEmitter from "./eventEmitter";
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export default class Time extends EventEmitter {
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constructor() {
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super();
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this.start = Date.now();
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this.current = this.start;
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this.elapsed = 0;
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this.delta = 16;
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// 合适的时机执行loop循环
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window.requestAnimationFrame(() => {
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this.tick();
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});
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}
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tick() {
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const currentTime = Date.now();
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this.delta = currentTime - this.current;
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this.current = currentTime;
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this.elapsed = this.current - this.start;
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this.trigger('tick');
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this.loopId = window.requestAnimationFrame(() => {
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this.tick();
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});
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}
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destroy() {
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window.cancelAnimationFrame(this.loopId);
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this.off('tick');
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}
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}
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