使用vue学习three.js之高级几何体-管状几何体TubeGeometry

1.TubeGeometry管状几何体介绍

TubeGeometry可以沿着一条三维样条曲线拉伸出一根管子。可以通过指定顶点来定义路径。创建TubeGeometry管道几何体时可输入以下参数：

属性	必须	描述
path	是	该属性用一个THREE.SplineCurve对象来指定管道遵循的路径
segments	否	该属性指定管道的分段数，路径越长指定的段数应该越多，默认值是64
radius	否	该属性指定管道的半径，默认值是1
radiusSegments	否	该属性指定管道截面的分段数，段数越多管道看上去越光滑，默认值是8
closed	否	该属性来设置管道是否收尾连接，默认值false

创建管道几何体TubeGeometry的方式如下：

const points = []
//随机生成点
for (let i = 0; i < this.properties.numberOfPoints.value; i++) {
    
    
  const randomX = -20 + Math.round(Math.random() * 50)
  const randomY = -15 + Math.round(Math.random() * 40)
  const randomZ = -20 + Math.round(Math.random() * 40)

  points.push(new THREE.Vector3(randomX, randomY, randomZ))
}
// 创建管状几何体
const geom = new THREE.TubeGeometry(
  new THREE.SplineCurve3(points), //创建样条曲线
  segments,//管道的分段数
  radius,//管道半径
  radiusSegments,//管道截面圆的分段数
  closed//是否头尾连接
)

2.demo说明

如上图，该示例支持以下功能

1. 通过numOfPoints属性调整创建管状几何体的路径需要的点的数量
2. 通过segments属性指定管道的分段数
3. 通过radius属性指定管道半径
4. 通过radiusSegments属性指定管道截面圆的分段数
5. 通过closed属性设置管状几何体是否收尾相连

3.demo代码

<template>
  <div>
    <div id="container"></div>
    <div class="controls-box">
      <section>
        <el-row>
          <div v-for="(item,key) in properties" :key="key">
            <div v-if="item&&item.name!=undefined">
              <el-col :span="8">
                <span class="vertice-span">{
    
    {
    
    item.name}}</span>
              </el-col>
              <el-col :span="13">
                <el-slider v-model="item.value" :min="item.min" :max="item.max" :step="item.step" :format-tooltip="formatTooltip" @change="redraw(item.name)"></el-slider>
              </el-col>
              <el-col :span="3">
                <span class="vertice-span">{
    
    {
    
    item.value}}</span>
              </el-col>
            </div>
          </div>
        </el-row>
        <el-row>
          <el-checkbox v-model="properties.closed" @change="redraw">closed</el-checkbox>
        </el-row>
      </section>
    </div>
  </div>
</template>

<script>
import * as THREE from 'three'
import {
    
     OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
import {
    
     SceneUtils } from 'three/examples/jsm/utils/SceneUtils.js'
export default {
    
    
  data() {
    
    
    return {
    
    
      properties: {
    
    
        numberOfPoints: {
    
    
          name: 'numberOfPoints',
          value: 7,
          min: 2,
          max: 15,
          step: 1
        },
        segments: {
    
    
          name: 'segments',
          value: 120,
          min: 0,
          max: 200,
          step: 1
        },
        radius: {
    
    
          name: 'radius',
          value: 2,
          min: 0,
          max: 20,
          step: 0.1
        },
        radiusSegments: {
    
    
          name: 'radiusSegments',
          value: 22,
          min: 0,
          max: 100,
          step: 1
        },
        closed: false
      },
      points: [],
      isNeedChangePoints: true,
      step: 1,
      spGroup: null,
      mesh: null,
      camera: null,
      scene: null,
      renderer: null,
      controls: null
    }
  },
  mounted() {
    
    
    this.init()
  },
  methods: {
    
    
    formatTooltip(val) {
    
    
      return val
    },
    // 初始化
    init() {
    
    
      this.createScene() // 创建场景
      this.createMesh() // 创建网格模型
      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()
    },

    // 创建网格模型
    createMesh() {
    
    
      if (this.isNeedChangePoints) {
    
    
        this.generatePoints() //初始化点集
      }
      this.isNeedChangePoints = false
      // 创建管状几何体
      const geom = new THREE.TubeGeometry(
        new THREE.SplineCurve3(this.points), //创建样条曲线
        this.properties.segments.value,
        this.properties.radius.value,
        this.properties.radiusSegments.value,
        this.properties.closed
      )
      // 创建材质
      const meshMaterial = new THREE.MeshBasicMaterial({
    
    
        color: 0x00ff00,
        transparent: true,
        opacity: 0.2
      })
      const wireFrameMat = new THREE.MeshBasicMaterial({
    
     wireframe: true })

      // 创建网格对象
      this.mesh = SceneUtils.createMultiMaterialObject(geom, [
        meshMaterial,
        wireFrameMat
      ])
      // 网格对象添加到场景中
      this.scene.add(this.mesh)
    },
    generatePoints() {
    
    
      this.points = []
      //生成指定数量的点
      for (let i = 0; i < this.properties.numberOfPoints.value; i++) {
    
    
        const randomX = -20 + Math.round(Math.random() * 50)
        const randomY = -15 + Math.round(Math.random() * 40)
        const randomZ = -20 + Math.round(Math.random() * 40)

        this.points.push(new THREE.Vector3(randomX, randomY, randomZ))
      }
      this.spGroup = new THREE.Group()
      const material = new THREE.MeshBasicMaterial({
    
    
        color: 0xff0000,
        transparent: false
      })
      // 根据每个点创建mesh对象并添加到场景
      this.points.forEach(point => {
    
    
        const spGeom = new THREE.SphereGeometry(0.2)
        const spMesh = new THREE.Mesh(spGeom, material)
        spMesh.position.copy(point)
        this.spGroup.add(spMesh)
      })
      // 点集添加到场景
      this.scene.add(this.spGroup)
      return this.points
    },

    // 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(-40, 60, -10)
      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(-80, 60, 40) // 设置相机位置

      this.camera.lookAt(new THREE.Vector3(10, 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)
    },

    // 重新绘制
    redraw(attributeName) {
    
    
      debugger
      if (attributeName === 'numberOfPoints') {
    
    
        this.scene.remove(this.spGroup)
        this.generatePoints()
      }

      this.scene.remove(this.mesh)
      this.createMesh()
    },
    render() {
    
    
      this.spGroup.rotation.y = this.step
      this.mesh.rotation.y = this.step += 0.01
      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%;
}
.controls-box {
    
    
  position: absolute;
  right: 5px;
  top: 5px;
  width: 300px;
  padding: 10px;
  background-color: #fff;
  border: 1px solid #c3c3c3;
}
.vertice-span {
    
    
  line-height: 38px;
  padding: 0 2px 0 10px;
}
</style>