1.demo效果
如上图，该demo通过PLYLoader加载了PLY格式的模型，将汽车模型呈现在页面中
2.实现要点
2.1 PLY模型放置路径
vue中加载文件时默认的路径为public下，所以需要加载的文件放在该路径下，同时在vue的data属性中创建变量publicPath，此变量的值是vue中的环境变量process.env.BASE_URL
data() {
return {
publicPath: process.env.BASE_URL
}
}
2.2 加载PLY模型
这我们通过PLYLoader导入模型，不过这里需要注意导入的路径，把我们创建的publicpath变量拼接到文件的路径上，在导入的回调函数中可以进行相关处理具体如下：
const loader = new PLYLoader()
loader.load(`${
THIS.publicPath}models/test.ply`, model => {
//对导入模型进行相关处理
...
})
2.3 创建粒子材质纹理
//生成纹理
generateSprite() {
const canvas = document.createElement('canvas')
canvas.width = 16
canvas.height = 16
const context = canvas.getContext('2d')
const gradient = context.createRadialGradient(
canvas.width / 2,
canvas.height / 2,
0,
canvas.width / 2,
canvas.height / 2,
canvas.width / 2
)
gradient.addColorStop(0, 'rgba(255,255,255,1)')
gradient.addColorStop(0.2, 'rgba(0,255,255,1)')
gradient.addColorStop(0.4, 'rgba(0,0,64,1)')
gradient.addColorStop(1, 'rgba(0,0,0,1)')
context.fillStyle = gradient
context.fillRect(0, 0, canvas.width, canvas.height)
const texture = new THREE.Texture(canvas)
texture.needsUpdate = true
return texture
}
2.4 格式化为粒子系统
// 创建粒子材质
const material = new THREE.PointsMaterial({
color: 0xffffff,
size: 0.4,
opacity: 0.6,
transparent: true,
blending: THREE.AdditiveBlending,
map: this.generateSprite()
})
// 创建粒子系统
this.mesh = new THREE.Points(geometry, material)
// 添加到场景
this.scene.add(this.mesh)
3.demo代码
<template>
<div>
<div id="container"></div>
</div>
</template>
<script>
import * as THREE from 'three'
import {
OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
import {
PLYLoader } from 'three/examples/jsm/loaders/PLYLoader.js'
export default {
data() {
return {
publicPath: process.env.BASE_URL,
mesh: null,
camera: null,
scene: null,
renderer: null,
controls: null
}
},
mounted() {
this.init()
},
methods: {
// 初始化
init() {
this.createScene() // 创建场景
this.loadPLY() // 加载PLY模型
this.createLight() // 创建光源
this.createCamera() // 创建相机
this.createRender() // 创建渲染器
this.createControls() // 创建控件对象
this.render() // 渲染
},
// 创建场景
createScene() {
this.scene = new THREE.Scene()
},
// 加载PLY模型
loadPLY() {
const THIS = this
const loader = new PLYLoader()
loader.load(`${
THIS.publicPath}models/test.ply`, geometry => {
// 创建粒子材质
const material = new THREE.PointsMaterial({
color: 0xffffff,
size: 0.4,
opacity: 0.6,
transparent: true,
blending: THREE.AdditiveBlending,
map: this.generateSprite()
})
// 创建粒子系统
this.mesh = new THREE.Points(geometry, material)
// 添加到场景
this.scene.add(this.mesh)
})
},
//生成纹理
generateSprite() {
const canvas = document.createElement('canvas')
canvas.width = 16
canvas.height = 16
const context = canvas.getContext('2d')
const gradient = context.createRadialGradient(
canvas.width / 2,
canvas.height / 2,
0,
canvas.width / 2,
canvas.height / 2,
canvas.width / 2
)
gradient.addColorStop(0, 'rgba(255,255,255,1)')
gradient.addColorStop(0.2, 'rgba(0,255,255,1)')
gradient.addColorStop(0.4, 'rgba(0,0,64,1)')
gradient.addColorStop(1, 'rgba(0,0,0,1)')
context.fillStyle = gradient
context.fillRect(0, 0, canvas.width, canvas.height)
const texture = new THREE.Texture(canvas)
texture.needsUpdate = true
return texture
},
// 创建光源
createLight() {
// 环境光
const ambientLight = new THREE.AmbientLight(0xffffff, 0.1) // 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(50, 50, 50)
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(20, 20, 20) // 设置相机位置
this.camera.lookAt(new THREE.Vector3(10, 40, 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() {
if (this.mesh) {
this.mesh.rotation.y += 0.006
}
this.renderer.render(this.scene, this.camera)
requestAnimationFrame(this.render)
},
// 创建控件对象
createControls() {
this.controls = new OrbitControls(this.camera, this.renderer.domElement)
}
}
}
</script>
<style>
#container {
position: absolute;
width: 100%;
height: 100%;
}
</style>