living-together/source/Model/Actuator.ts

import { Model } from "@Model/Model";
import { Emitter } from "@Model/Emitter";
import { Clip } from "@Model/Clip";

enum ActuatorModel {
	Play = 1,
	Record = 2,
	View = 3,
	Offline = 4
}

interface IActuatorEvent {
	startChange: boolean;
	record: number;
	loop: number;
}

/**
 * 模型执行器
 */
class Actuator extends Emitter<IActuatorEvent> {

	/**
	 * 速度系数
	 */
	public speed: number = 1;

	/**
	 * 模拟帧率
	 */
	public fps: number = 36;

	/**
	 * 仿真是否进行
	 */
	private startFlag: boolean = false;

	/**
	 * 模式
	 */
	public mod: ActuatorModel = ActuatorModel.View;

	/**
	 * 录制剪辑
	 */
	public recordClip?: Clip;

	/**
	 * 开始录制
	 */
	public startRecord(clip: Clip) {

		// 记录录制片段
		this.recordClip = clip;

		// 如果仿真未开启，开启仿真
		if (!this.start()) this.start(true);

		// 设置状态
		this.mod = ActuatorModel.Record;
	}

	/**
	 * 结束录制
	 */
	public endRecord() {

		// 如果仿真未停止，停止仿真
		if (this.start()) this.start(false);

		// 设置状态
		this.mod = ActuatorModel.View;
	}

	/**
	 * 主时钟状态控制
	 */
	public start(start?: boolean): boolean {
		if (start === undefined) {
			return this.startFlag;
		} else {
			this.startFlag = start;
			this.lastTime = 0;
			this.alignTimer = 0;
			this.emit("startChange", start);
			return start;
		}
	}

	/**
	 * 绑定模型
	 */
	public model: Model;

	/**
	 * 上一帧的时间
	 */
	private lastTime: number = 0;

	/**
	 * 对其计时器
	 */
	private alignTimer: number = 0;

	public tickerType: 1 | 2 = 2;

	private ticker(t: number) {
		if (this.startFlag && t !== 0) {
			if (this.lastTime === 0) {
				this.lastTime = t;
			} else {
				let durTime = (t - this.lastTime) / 1000;
				this.lastTime = t;

				// 丢帧判定
				if (durTime > 0.1) {
					console.log("Actuator: Ticker dur time error. dropping...")
				} else {
					this.alignTimer += durTime;
					if (this.alignTimer > (1 / this.fps)) {

						// 更新模型
						this.model.update(this.alignTimer * this.speed);

						// 绘制模型
						this.model.draw();

						// 录制模型
						if (
							this.mod === ActuatorModel.Record ||
							this.mod === ActuatorModel.Offline
						) {
							this.recordClip?.record(this.alignTimer * this.speed);
							this.emit("record", this.alignTimer);
						}

						this.emit("loop", this.alignTimer);
						this.alignTimer = 0;
					}
				}
			}
		}
		
		else {
			this.emit("loop", Infinity);
		}
	}

	/**
	 * 帧率对其时钟
	 * 1、使用 requestAnimationFrame 保证最高的性能
	 * 2、最大模拟帧率只能小于 60
	 * 3、可能出现帧率对其问题
	 */
	private tickerAlign = (t: number) => {
		this.ticker(t);
		requestAnimationFrame(this.tickerAlign);
	}

	/**
	 * 精确时钟
	 */
	private tickerExp = () => {
		this.ticker(window.performance.now());
		setTimeout(this.tickerExp, (1 / this.fps) * 1000);
	}

	/**
	 * 执行器
	 */
	private runTicker = (t: number) => {
		if (this.tickerType === 1) {
			this.ticker(t);
			requestAnimationFrame(this.runTicker);
		} else {
			this.ticker(window.performance.now());
			setTimeout(this.runTicker, (1 / this.fps) * 1000);
		}
	}

	public constructor(model: Model) {
		super();
		this.model = model;
		this.runTicker(0);
	}
}

export { Actuator, ActuatorModel }