使用vue学习three.js之创建动画和移动相机-使用第一人称控件FirstPersonControls控制相机

1.demo效果

如上图，该demo通过第一人称控件FirstPersonControls控制相机。实现像第一人称射击游戏一样使用键盘移动角色，使用鼠标控制视角

2.FirstPersonControls介绍

通过第一人称控件FirstPersonControls 可以实现使用键盘移动相机，使用鼠标控制视角

FirstPersonControls操控说明
以下是操控和动作的比对说明

3. 实现要点

3.1 vue中引入FirstPersonControls控制器

在项目工程中引入FirstPersonControls控制器如下

import {
    FirstPersonControls } from 'three/examples/jsm/controls/FirstPersonControls.js''

3.2 创建第一人称控件实例

// 创建第一人称控件
createFlyControls() {
   
  this.clock = new THREE.Clock()
  this.firstPersonControls = new FirstPersonControls(
    this.camera,
    this.renderer.domElement
  )

  this.firstPersonControls.lookSpeed = 0.4 //鼠标移动查看的速度
  this.firstPersonControls.movementSpeed = 20 //相机移动速度
  this.firstPersonControls.noFly = true
  this.firstPersonControls.lookVertical = true
  this.firstPersonControls.constrainVertical = true //约束垂直
  this.firstPersonControls.verticalMin = 1.0
  this.firstPersonControls.verticalMax = 2.0
  this.firstPersonControls.lon = -150 //进入初始视角x轴的角度
  this.firstPersonControls.lat = 120 //初始视角进入后y轴的角度
}

3.3 render中更新第一人称控件

render() {
   
  const delta = this.clock.getDelta() //获取自上次调用的时间差
  this.firstPersonControls.update(delta) //更新第一人称控件
  this.renderer.render(this.scene, this.camera)
  requestAnimationFrame(this.render)
}

4. demo代码

<template>
  <div>
    <div id="container" />
  </div>
</template>

<script>
import * as THREE from 'three'
import {
    FirstPersonControls } from 'three/examples/jsm/controls/FirstPersonControls.js'
import {
    OBJLoader } from 'three/examples/jsm/loaders/OBJLoader.js'

export default {
   
  data() {
   
    return {
   
      publicPath: process.env.BASE_URL,
      mesh: null,
      camera: null,
      scene: null,
      renderer: null,
      firstPersonControls: null,
      clock: null
    }
  },
  mounted() {
   
    this.init()
  },
  methods: {
   
    // 初始化
    init() {
   
      this.createScene() // 创建场景
      this.loadObj() // 加载OBJ模型
      this.createLight() // 创建光源
      this.createCamera() // 创建相机
      this.createRender() // 创建渲染器
      this.createFlyControls() // 创建第一人称控件
      this.render() // 渲染
    },
    // 创建场景
    createScene() {
   
      this.scene = new THREE.Scene()
    },
    loadObj() {
   
      const objLoader = new OBJLoader()
      const THIS = this

      objLoader.load(`${
     THIS.publicPath}models/city.obj`, loadedMesh => {
   
        THIS.mesh = loadedMesh
        loadedMesh.scale.set(0.2, 0.2, 0.2)
        THIS.setRandomColors(loadedMesh, THIS)
        THIS.scene.add(THIS.mesh)
      })
    },
    setRandomColors(object, THIS) {
   
      const children = object.children

      if (children && children.length > 0) {
   
        children.forEach(function(e) {
   
          THIS.setRandomColors(e, THIS)
        })
      } else {
   
        if (object instanceof THREE.Mesh) {
   
          const colorIndex = Math.floor(Math.random() * 3) // 0~2的随机数
          const colorArray = [
            new THREE.Color(0xff0000),
            new THREE.Color(0x00ff00),
            new THREE.Color(0x0000ff)
          ]
          object.material.emissive = colorArray[colorIndex]
          object.material.color = colorArray[colorIndex]
          object.material.transparent = true
          object.material.opacity = 0.3
        }
      }
    },
    // 创建光源
    createLight() {
   
      // 环境光
      const ambientLight = new THREE.AmbientLight(0x383838) // 创建环境光
      this.scene.add(ambientLight) // 将环境光添加到场景

      const spotLight = new THREE.SpotLight(0xffffff) // 创建聚光灯
      spotLight.position.set(200, 200, 200)
      spotLight.castShadow = true
      this.scene.add(spotLight)
    },
    // 创建相机
    createCamera() {
   
      const element = document.getElementById('container')
      const width = element.clientWidth // 窗口宽度
      const height = element.clientHeight // 窗口高度
      const k = width / height // 窗口宽高比
      // PerspectiveCamera( fov, aspect, near, far )
      this.camera = new THREE.PerspectiveCamera(35, k, 0.1, 1000)
      this.camera.position.set(100, 10, 10) // 设置相机位置

      this.camera.lookAt(new THREE.Vector3(0, 0, 0)) // 设置相机方向
      this.scene.add(this.camera)
    },
    // 创建渲染器
    createRender() {
   
      const element = document.getElementById('container')
      this.renderer = new THREE.WebGLRenderer({
    antialias: true, alpha: true })
      this.renderer.setSize(element.clientWidth, element.clientHeight) // 设置渲染区域尺寸
      this.renderer.shadowMap.enabled = true // 显示阴影
      this.renderer.shadowMap.type = THREE.PCFSoftShadowMap
      this.renderer.setClearColor(0x3f3f3f, 1) // 设置背景颜色
      element.appendChild(this.renderer.domElement)
    },

    render() {
   
      const delta = this.clock.getDelta() //获取自上次调用的时间差
      this.firstPersonControls.update(delta) //更新第一人称控件
      this.renderer.render(this.scene, this.camera)
      requestAnimationFrame(this.render)
    },
    // 创建第一人称控件
    createFlyControls() {
   
      this.clock = new THREE.Clock()
      this.firstPersonControls = new FirstPersonControls(
        this.camera,
        this.renderer.domElement
      )

      this.firstPersonControls.lookSpeed = 0.4 //鼠标移动查看的速度
      this.firstPersonControls.movementSpeed = 20 //相机移动速度
      this.firstPersonControls.noFly = true
      this.firstPersonControls.lookVertical = true
      this.firstPersonControls.constrainVertical = true //约束垂直
      this.firstPersonControls.verticalMin = 1.0
      this.firstPersonControls.verticalMax = 2.0
      this.firstPersonControls.lon = -150 //进入初始视角x轴的角度
      this.firstPersonControls.lat = 120 //初始视角进入后y轴的角度
    }
  }
}
</script>
<style>
#container {
   
  position: absolute;
  width: 100%;
  height: 100%;
}
</style>