让AI来告诉你什么叫幽灵堵车

使用环境参考

CocosCreator v3.7.2
ChatGPT

正文

什么是幽灵堵车

堵车，大家都不陌生！

堵车时我就思维发散，用 CocosCreator 模拟下堵车应该挺好玩，网上总说高速上最前面如果有个龟速的车，后面能堵车堵个两三公里。查了一下这叫“幽灵堵车”。问下 ChatGPT：

然后我就新建了个项目，从官方商城搞个车过来：

让 AI 帮你打代码

接下来就是让 AI 来敲代码的过程，要想让 AI 明白你的意思，你得尽可能详细的描述当前的环境以及你想要的东西！！

接下来是我们长长的长长的长长的对话：

参数的修改

代码终于成功跑起来了，然后速度过快，最大最小速度缩小了 50 倍左右，效果如下：

给出代码

import { _decorator, Component, Node, Prefab, instantiate, Vec3 } from "cc";
const { ccclass, property } = _decorator;

@ccclass("Main")
export class Main extends Component {
  @property(Prefab)
  carPrefab: Prefab = null!;

  private carList: { speed: number; carNode: Node }[] = [];
  private time: number = 0;
  private interval: number = 3;

  start() {
    this.addCar();
  }

  update(dt: number) {
    this.time += dt;
    if (this.time > this.interval) {
      this.addCar();
      this.time = 0;
    }

    this.moveCars(dt);
  }

  private addCar() {
    const carNode = instantiate(this.carPrefab);
    carNode.parent = this.node;
    const car = { speed: 1, carNode: carNode };
    this.carList.push(car);
  }

  private moveCars(dt: number) {
    for (let i = 0; i < this.carList.length; i++) {
      const car = this.carList[i];
      const carPosition = car.carNode.position;

      // 如果不是第一辆车，则判断与前一辆车的距离是否大于安全距离
      if (i > 0) {
        const frontCar = this.carList[i - 1];
        const frontCarPosition = frontCar.carNode.position;
        const distance = frontCarPosition.x - carPosition.x;
        if (distance < 4) {
          car.speed = Math.max(0, frontCar.speed - 1);
        } else {
          car.speed = Math.min(1, frontCar.speed + 1);
        }
      }

      const newCarPosition = carPosition.add(new Vec3(car.speed * dt, 0, 0));
      car.carNode.setPosition(newCarPosition);
    }
  }
}

让 AI 赋予小车加速度

一拍大腿，加速度给忘了，我说走的这么立正！！

接下来通过对话让 ai 给代码加上加速度，然后再写一个摄像机控制逻辑：

效果如图：

当车辆数量到达 40 左右时，就已经出现两段长时间的拥堵了，幽灵堵车-可视化 okk！！

当车辆 200+ 时，车辆会以 10 个左右为一组，组团摇摆，这还是大家反应力 MAX 理想情况！

最终代码：

// 挂载 root 空节点
import { _decorator, Component, Node, Prefab, instantiate, Vec3 } from "cc";
const { ccclass, property } = _decorator;

@ccclass("Main")
export class Main extends Component {
  @property(Prefab)
  carPrefab: Prefab = null!;

  private carList: { speed: number; carNode: Node }[] = [];
  private time: number = 0;
  private interval: number = 3;

  start() {
    this.addCar();
  }

  update(dt: number) {
    this.time += dt;
    if (this.time > this.interval) {
      this.addCar();
      this.time = 0;
    }

    this.moveCars(dt);
  }

  private addCar() {
    const carNode = instantiate(this.carPrefab);
    carNode.parent = this.node;
    const car = { speed: 5, carNode: carNode };
    this.carList.push(car);
  }

  private moveCars(dt: number) {
    const acceleration = 0.35; // 加速度
    const drag = 0.05; // 阻力系数

    for (let i = 0; i < this.carList.length; i++) {
      const car = this.carList[i];
      const carPosition = car.carNode.position;

      // 如果不是第一辆车，则判断与前一辆车的距离是否大于安全距离
      if (i > 0) {
        const frontCar = this.carList[i - 1];
        const frontCarPosition = frontCar.carNode.position;
        const distance = frontCarPosition.x - carPosition.x;
        if (distance < 5) {
          car.speed = Math.max(0, car.speed - acceleration - drag);
        } else {
          car.speed = Math.min(10, car.speed + acceleration - drag);
        }
      } else {
        // 第一辆车匀速低速行驶
        car.speed = Math.min(2, car.speed + acceleration - drag);
      }

      const newCarPosition = carPosition.add(new Vec3(car.speed * dt, 0, 0));
      car.carNode.setPosition(newCarPosition);
    }
  }
}

// 挂载 camera 摄像机节点
import {
  _decorator,
  Component,
  Vec3,
  systemEvent,
  SystemEvent,
  EventKeyboard,
  KeyCode,
} from "cc";

const { ccclass, property } = _decorator;

@ccclass("Camera")
export class Camera extends Component {
  @property({ type: Number })
  moveSpeed: number = 5;

  private _isMovingLeft: boolean = false;
  private _isMovingRight: boolean = false;

  start() {
    systemEvent.on(SystemEvent.EventType.KEY_DOWN, this.onKeyDown, this);
    systemEvent.on(SystemEvent.EventType.KEY_UP, this.onKeyUp, this);
  }

  update(deltaTime: number) {
    let deltaMove = new Vec3();
    if (this._isMovingLeft) {
      deltaMove.x -= this.moveSpeed * deltaTime;
    }
    if (this._isMovingRight) {
      deltaMove.x += this.moveSpeed * deltaTime;
    }
    this.node.translate(deltaMove);
  }

  private onKeyDown(event: EventKeyboard) {
    switch (event.keyCode) {
      case KeyCode.KEY_A:
        this._isMovingLeft = true;
        break;
      case KeyCode.KEY_D:
        this._isMovingRight = true;
        break;
    }
  }

  private onKeyUp(event: EventKeyboard) {
    switch (event.keyCode) {
      case KeyCode.KEY_A:
        this._isMovingLeft = false;
        break;
      case KeyCode.KEY_D:
        this._isMovingRight = false;
        break;
    }
  }
}