阅读 3770
用最简单方式打造Three.js 3D汽车展示厅

用最简单方式打造Three.js 3D汽车展示厅

前言

在上一篇文章简单粗略的描述了开发3D汽车展厅,笔者想再写一篇比较详细的教程。对于笔者来说Three.js说难不难,说简单也不简单。说简单因为他简化了对三维知识的理解,简化了很多操作。说难是因为api很多,要用熟也不是一朝半夕的时间。笔者在这给大家介绍一下以最简单方式打造一个3D汽车展示厅。这个3D汽车展厅实现出来也不算完整,主要想让同学们找找感觉,找些成就感,有感觉自己也有学下去的动力。^_^

简单粗略了解三维

在2D里只有两个坐标,分别是X轴,和Y轴。在3D就多了一个Z轴。相信刚学3D的同学对X轴和Y轴都比较熟悉,Z轴是比较陌生,笔者建议大家可以上 three编辑器的网站尝试创建一些几何物体,找找对3D理解。

image.png

完整效果

屏幕录制2021-07-08 下午1.39.03.gif

需要了解这几个概念

笔者用舞台表演来比如:

  1. 场景 Sence 相当于一个舞台,在这里是布置场景物品和表演者表演的地方
  2. 相机 Carma 相当于观众的眼睛去观看
  3. 几何体 Geometry 相当于舞台的表演者
  4. 灯光 light 相当于舞台灯光照射
  5. 控制 Controls 相当于这出舞台剧的总导演

既然知道这几个概念,我们就根据这几大概念以函数形式区分,就很好理解。在这个three程序我分别创建了: setScenesetCarmaloadfilesetLightsetControls分别对应以上几个概念

创建场景

首先我们还是用vue3的setup方式编写,npm安装three包, 引入 SceneWebGLRenderer 两个对象,创建两个变量 scenerenderer并赋值,这样就简单搭建了一个场景,场景背景默认是黑色。创建一个init初始化函数,并在onMounted调用

<script setup>
  import {onMounted} from 'vue'
  import { Scene,WebGLRenderer,PerspectiveCamera} from 'three'
  let scene,renderer
  //创建场景
  const setScene = ()=>{
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)
    }
   //初始化所有函数 
   const init = () => {
        setScene()
    }
    //用vue钩子函数调用
    onMounted(init)
</script>
复制代码

创建相机

有了场景就要加相机,相机相当于人的眼睛去观察几何物体,引入PerspectiveCamera, 参数有4个,具体可以看看官网文档。然后通过实例方法position.set设置相机坐标

<script setup>
  import { Scene,WebGLRenderer,PerspectiveCamera} from 'three'
  let scene,renderer,camera
  //相机的默认坐标
  const defaultMap = {
        x: 510,
        y: 128,
        z: 0,
    }
  //创建场景
  const setScene = ()=>{
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)
    }
  //创建相机  
  const setCamera = () => {
        const {x, y, z} = defaultMap
        camera = new PerspectiveCamera(60, innerWidth / innerHeight, 1, 1000)
        camera.position.set(x, y, z)
    }
   //初始化所有函数 
   const init = () => {
        setScene()
        setCamera()
    }
    //用vue钩子函数调用
    onMounted(init)
</script>
复制代码

引入特斯拉模型

image.png 在three我们除了可以通过api创建几何物体,还可以引入第三方3d模型,具体可以上 sketchfab ,国外一个3d模型下载网站,里面有很多免费的模型下载,这次用特斯拉汽车模型为例,下载一个gltf格式的3D模型。引入GLTFLoader 创建一个loadfile函数并通过Promise返回模型数据,在init函数加上async调用loadfile得到返回模型数据并添加到场景scene

  import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader'
  import { Scene,WebGLRenderer,PerspectiveCamera} from 'three'
  let scene,renderer,camera,directionalLight,dhelper
  let isLoading = ref(true)
  let loadingWidth = ref(0)
  //相机的默认坐标
  const defaultMap = {
        x: 510,
        y: 128,
        z: 0,
    }
  //创建场景
  const setScene = ()=>{
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)
    }
  //创建相机  
  const setCamera = () => {
        const {x, y, z} = defaultMap
        camera = new PerspectiveCamera(60, innerWidth / innerHeight, 1, 1000)
        camera.position.set(x, y, z)
    }
    //通过Promise处理一下loadfile函数
     const loadFile = (url) => {
        return new Promise(((resolve, reject) => {
            loader.load(url,
                (gltf) => {
                    resolve(gltf)
                }, ({loaded, total}) => {
                    let load = Math.abs(loaded / total * 100)
                    loadingWidth.value = load
                    if (load >= 100) {
                        setTimeout(() => {
                            isLoading.value = false
                        }, 1000)
                    }
                    console.log((loaded / total * 100) + '% loaded')
                },
                (err) => {
                    reject(err)
                }
            )
        }))
    }
    
    //初始化所有函数 
   const init = async() => {
        const gltf =await loadFile('src/assets/3d/tesla_2018_model_3/scene.gltf')
        setScene()
        setCamera()
        scene.add(gltf.scene)
    }
    //用vue钩子函数调用
    onMounted(init) 

复制代码

创建灯光

汽车模型还看不见,所以我们要给它设置灯光,引入DirectionalLight,DirectionalLightHelper,HemisphereLight,HemisphereLightHelper,并设置灯光的参数,使模型可见,并有些反射光面,阴影的效果,然后也在init函数调用 setLight,再增加loop函数,使场景、照相机、模型不停循环调用。然后车模型就能看见啦,看到车出现的那一刻,好像自己的新买的一样,^_^

image.png

  import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader'
 import { Scene,WebGLRenderer,PerspectiveCamera,   DirectionalLight,
        DirectionalLightHelper,
        HemisphereLight,
        HemisphereLightHelper} from 'three'
  let scene,renderer,camera,directionalLight,hemisphereLight,dhelper,hHelper
  let isLoading = ref(true)
  let loadingWidth = ref(0)
  //相机的默认坐标
  const defaultMap = {
        x: 510,
        y: 128,
        z: 0,
    }
  //创建场景
  const setScene = ()=>{
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)
    }
  //创建相机  
  const setCamera = () => {
        const {x, y, z} = defaultMap
        camera = new PerspectiveCamera(60, innerWidth / innerHeight, 1, 1000)
        camera.position.set(x, y, z)
    }
    //通过Promise处理一下loadfile函数
     const loadFile = (url) => {
        return new Promise(((resolve, reject) => {
            loader.load(url,
                (gltf) => {
                    resolve(gltf)
                }, ({loaded, total}) => {
                    let load = Math.abs(loaded / total * 100)
                    loadingWidth.value = load
                    if (load >= 100) {
                        setTimeout(() => {
                            isLoading.value = false
                        }, 1000)
                    }
                    console.log((loaded / total * 100) + '% loaded')
                },
                (err) => {
                    reject(err)
                }
            )
        }))
    }
    // 设置灯光
     const setLight = () => {
        directionalLight = new DirectionalLight(0xffffff, 0.5)
        directionalLight.position.set(-4, 8, 4)
        dhelper = new DirectionalLightHelper(directionalLight, 5, 0xff0000)
        hemisphereLight = new HemisphereLight(0xffffff, 0xffffff, 0.4)
        hemisphereLight.position.set(0, 8, 0)
        hHelper = new HemisphereLightHelper(hemisphereLight, 5)
        scene.add(directionalLight)
        scene.add(hemisphereLight)
    }
    //初始化所有函数 
   const init = async() => {
        const gltf = await loadFile('src/assets/3d/tesla_2018_model_3/scene.gltf')
        setScene()
        setCamera()
        setLight()
        scene.add(gltf.scene)
       loop()
    }
    //使场景、照相机、模型不停调用
     const loop = () => {
        requestAnimationFrame(loop)
        renderer.render(scene, camera)
    }
    //用vue钩子函数调用
    onMounted(init) 

复制代码

控制模型

屏幕录制2021-07-08 下午12.04.36.gif

想用鼠标自由旋转,或者自动旋转,就要引用 OrbitControls对象,创建setControls函数也是在init调用,通过绑定change还可以监听坐标变化,另外也要在loop函数增加 controls.update()才可以更新位置变化

  import { Scene,WebGLRenderer,PerspectiveCamera} from 'three'
  import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader'
  import {OrbitControls} from 'three/examples/jsm/controls/OrbitControls.js'

  let scene,renderer,camera,directionalLight,hemisphereLight,dhelper,hHelper,controls
  let isLoading = ref(true)
  let loadingWidth = ref(0)
  //相机的默认坐标
  const defaultMap = {
        x: 510,
        y: 128,
        z: 0,
    }
  //创建场景
  const setScene = ()=>{
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)
    }
  //创建相机  
  const setCamera = () => {
        const {x, y, z} = defaultMap
        camera = new PerspectiveCamera(60, innerWidth / innerHeight, 1, 1000)
        camera.position.set(x, y, z)
    }
    //通过Promise处理一下loadfile函数
     const loadFile = (url) => {
        return new Promise(((resolve, reject) => {
            loader.load(url,
                (gltf) => {
                    resolve(gltf)
                }, ({loaded, total}) => {
                    let load = Math.abs(loaded / total * 100)
                    loadingWidth.value = load
                    if (load >= 100) {
                        setTimeout(() => {
                            isLoading.value = false
                        }, 1000)
                    }
                    console.log((loaded / total * 100) + '% loaded')
                },
                (err) => {
                    reject(err)
                }
            )
        }))
    }
    // 设置灯光
     const setLight = () => {
        directionalLight = new DirectionalLight(0xffffff, 0.5)
        directionalLight.position.set(-4, 8, 4)
        dhelper = new DirectionalLightHelper(directionalLight, 5, 0xff0000)
        hemisphereLight = new HemisphereLight(0xffffff, 0xffffff, 0.4)
        hemisphereLight.position.set(0, 8, 0)
        hHelper = new HemisphereLightHelper(hemisphereLight, 5)
        scene.add(directionalLight)
        scene.add(hemisphereLight)
    }
    // 设置模型控制
    const setControls = () => {
        controls = new OrbitControls(camera, renderer.domElement)
        controls.maxPolarAngle = 0.9 * Math.PI / 2
        controls.enableZoom = true
        controls.addEventListener('change', render)
    }
    const render = () => {
        map.x = Number.parseInt(camera.position.x)
        map.y = Number.parseInt(camera.position.y)
        map.z = Number.parseInt(camera.position.z)
    }
    //初始化所有函数 
   const init = async() => {
        const gltf =await loadFile('src/assets/3d/tesla_2018_model_3/scene.gltf')
        setScene()
        setCamera()
        setLight()
        setControls()
        scene.add(gltf.scene)
    }
    
   //使场景、照相机、模型不停调用和更新位置数据
     const loop = () => {
        requestAnimationFrame(loop)
        renderer.render(scene, camera)
        controls.update()

    }
    
    //用vue钩子函数调用
    onMounted(init) 

复制代码

改变车身颜色

到这里基础的已经搭建好了,接下来我们再加一个功能改变汽车车身颜色,也是展厅展示一个比较基础的功能.创建一个setColor 这里说一下实例scene 有一个traverse函数,它回调了所有模型的子模型信息,只要我们找到对应name属性,就可以更改颜色,和增加贴图等等, 因为对模型结构不怎熟悉,所以根据名字来猜了一下 找到door_前序的名字大概应该就车身的套件。当然如果细分到我只想改引擎盖的颜色就要找出引擎盖套件。当然要很熟悉这个模型结构了

 
    //设置车身颜色
      const setCarColor = (index) => {
        const currentColor = new Color(colorAry[index])
        scene.traverse(child => {
            if (child.isMesh) {
                console.log(child.name)
                if (child.name.includes('door_')) {
                    child.material.color.set(currentColor)
                }
            }
        })
    }
   
复制代码

上完整代码

其他操作都是交给vue控制,包括设置车身颜色、是否自动转动等等。大家运行以下代码的时候记得用vite打包工具创建vue3模板

<template>
    <div class="boxs">
        <div class="maskLoading" v-if="isLoading">
            <div class="loading">
                <div :style="{width : loadingWidth +'%' }"></div>
            </div>
            <div style="padding-left: 10px;">{{parseInt(loadingWidth)}}%</div>
        </div>
        <div class="mask">
            <p>x : {{x}} y:{{y}} z :{{z}}</p>
            <button @click="isAutoFun">转动车</button>
            <button @click="stop">停止</button>
            <div class="flex">
                <div @click="setCarColor(index)" v-for="(item,index) in colorAry"
                     :style="{backgroundColor : item}"></div>
            </div>
        </div>
    </div>
</template>

<script setup>
    import {onMounted, reactive, ref, toRefs} from 'vue'
    import {
        Color,
        DirectionalLight,
        DirectionalLightHelper,
        HemisphereLight,
        HemisphereLightHelper,
        PerspectiveCamera,
        Scene,
        WebGLRenderer
    } from 'three'
    import {OrbitControls} from 'three/examples/jsm/controls/OrbitControls.js'
    import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader'
    //车身颜色数组
    const colorAry = [
        "rgb(216, 27, 67)", "rgb(142, 36, 170)", "rgb(81, 45, 168)", "rgb(48, 63, 159)", "rgb(30, 136, 229)", "rgb(0, 137, 123)",
        "rgb(67, 160, 71)", "rgb(251, 192, 45)", "rgb(245, 124, 0)", "rgb(230, 74, 25)", "rgb(233, 30, 78)", "rgb(156, 39, 176)",
        "rgb(0, 0, 0)"] // 车身颜色数组 
    const loader = new GLTFLoader() //引入模型的loader实例
    const defaultMap = {
        x: 510,
        y: 128,
        z: 0,
    }// 相机的默认坐标
    const map = reactive(defaultMap)//把相机坐标设置成可观察对象
    const {x, y, z} = toRefs(map)//输出坐标给模板使用
    let scene, camera, renderer, controls, floor, dhelper, hHelper, directionalLight, hemisphereLight // 定义所有three实例变量
    let isLoading = ref(true) //是否显示loading  这个load模型监听的进度
    let loadingWidth = ref(0)// loading的进度

    //创建灯光
    const setLight = () => {
        directionalLight = new DirectionalLight(0xffffff, 0.5)
        directionalLight.position.set(-4, 8, 4)
        dhelper = new DirectionalLightHelper(directionalLight, 5, 0xff0000)
        hemisphereLight = new HemisphereLight(0xffffff, 0xffffff, 0.4)
        hemisphereLight.position.set(0, 8, 0)
        hHelper = new HemisphereLightHelper(hemisphereLight, 5)
        scene.add(directionalLight)
        scene.add(hemisphereLight)
    }

    // 创建场景
    const setScene = () => {
        scene = new Scene()
        renderer = new WebGLRenderer()
        renderer.setSize(innerWidth, innerHeight)
        document.querySelector('.boxs').appendChild(renderer.domElement)

    }
    
    // 创建相机
    const setCamera = () => {
        const {x, y, z} = defaultMap
        camera = new PerspectiveCamera(60, innerWidth / innerHeight, 1, 1000)
        camera.position.set(x, y, z)
    }
    
    // 设置模型控制
    const setControls = () => {
        controls = new OrbitControls(camera, renderer.domElement)
        controls.maxPolarAngle = 0.9 * Math.PI / 2
        controls.enableZoom = true
        controls.addEventListener('change', render)
    }
    
    //返回坐标信息
     const render = () => {
        map.x = Number.parseInt(camera.position.x)
        map.y = Number.parseInt(camera.position.y)
        map.z = Number.parseInt(camera.position.z)
    }
    
    
 
    // 循环场景 、相机、 位置更新
    const loop = () => {
        requestAnimationFrame(loop)
        renderer.render(scene, camera)
        controls.update()
    }
    
 
    //是否自动转动
    const isAutoFun = () => {
        controls.autoRotate = true
    }
    //停止转动
    const stop = () => {
        controls.autoRotate = false
    }

    //设置车身颜色
    const setCarColor = (index) => {
        const currentColor = new Color(colorAry[index])
        scene.traverse(child => {
            if (child.isMesh) {
                console.log(child.name)
                if (child.name.includes('door_')) {
                    child.material.color.set(currentColor)
                }
            }
        })
    }
    
    const loadFile = (url) => {
        return new Promise(((resolve, reject) => {
            loader.load(url,
                (gltf) => {
                    resolve(gltf)
                }, ({loaded, total}) => {
                    let load = Math.abs(loaded / total * 100)
                    loadingWidth.value = load
                    if (load >= 100) {
                        setTimeout(() => {
                            isLoading.value = false
                        }, 1000)
                    }
                    console.log((loaded / total * 100) + '% loaded')
                },
                (err) => {
                    reject(err)
                }
            )
        }))
    }
    
    
       //初始化所有函数
    const init = async () => {
        setScene()
        setCamera()
        setLight()
        setControls()
        const gltf = await loadFile('src/assets/3d/tesla_2018_model_3/scene.gltf')
        scene.add(gltf.scene)
        loop()
    }
      //用vue钩子函数调用
    onMounted(init) 
</script>

<style>
    body {
        margin: 0;
    }

    .maskLoading {
        background: #000;
        position: fixed;
        display: flex;
        justify-content: center;
        align-items: center;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
        z-index: 1111111;
        color: #fff;
    }

    .maskLoading .loading {
        width: 400px;
        height: 20px;
        border: 1px solid #fff;
        background: #000;
        overflow: hidden;
        border-radius: 10px;

    }

    .maskLoading .loading div {
        background: #fff;
        height: 20px;
        width: 0;
        transition-duration: 500ms;
        transition-timing-function: ease-in;
    }

    canvas {
        width: 100%;
        height: 100%;
        margin: auto;
    }

    .mask {
        color: #fff;
        position: absolute;
        bottom: 0;
        left: 0;
        width: 100%;
    }

    .flex {
        display: flex;
        flex-wrap: wrap;
        padding: 20px;

    }

    .flex div {
        width: 10px;
        height: 10px;
        margin: 5px;
        cursor: pointer;
    }
</style>

复制代码

屏幕录制2021-07-08 下午1.39.03.gif

最后

在这个3D汽车展示厅笔者只是简单创建了一些基础功能,还有很多功能可以增加,比如创建背景、地板、一些阴影、定点显示车套件位置信息等等。掌握套路,这些功能实现也不难。另外笔者要冲二级啦,希望大家如果喜欢能给小弟点个赞,谢谢啦 ^_^

文章分类
前端
文章标签