Three.js 建筑线条教程

建筑线条 · Building Line · ▶ 在线运行案例

你将学到什么

  • OrbitControls 相机轨道交互
  • glTF/Draco 模型加载与优化
  • EdgesGeometry 模型边线提取
  • requestAnimationFrame 渲染循环与 resize 自适应

效果说明

本案例演示 建筑线条 效果:基于 WebGL 实现「建筑线条」可视化效果,附完整可运行源码;核心用到 OrbitControls、glTF/Draco、EdgesGeometry。建议先打开文首在线案例查看动态画面,再对照下方源码逐步理解。

核心概念

  • Scene / Camera / WebGLRenderer 构成最小渲染闭环;大场景可开 logarithmicDepthBuffer 缓解 Z-fighting。
  • OrbitControls 提供轨道旋转/缩放;开启 enableDamping 后需在 animate 中 controls.update()
  • 阅读下方完整源码时,建议从 init / load / animate 三条主线入手,再深入 shader 与工具函数。

实现步骤

  • 搭建 Scene、PerspectiveCamera、WebGLRenderer,挂载 canvas 并处理 resize
  • 异步加载模型 / 3D Tiles / GeoJSON 等资源并加入 scene 或 entities
  • 创建 OrbitControls(及 Raycaster 等交互控件,若源码包含)
  • requestAnimationFrame 循环中更新状态并 render(Cesium 为 viewer.render 或自动渲染)

代码要点

复制代码
  import * as THREE from 'three'

  import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
  import { GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader.js'
  import { LineSegments2 } from 'three/examples/jsm/lines/LineSegments2.js';
  import { LineMaterial } from 'three/examples/jsm/lines/LineMaterial.js';
  import { LineSegmentsGeometry } from 'three/examples/jsm/lines/LineSegmentsGeometry.js';



  const box = document.getElementById('box')



  const scene = new THREE.Scene()



  const camera = new THREE.PerspectiveCamera(75, box.clientWidth / box.clientHeight, 0.1, 100000)



  camera.position.set(1, 1, 1)



  const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true })



  renderer.setPixelRatio(window.devicePixelRatio * 1.3)



  renderer.setSize(box.clientWidth, box.clientHeight)



  box.appendChild(renderer.domElement)



  new OrbitControls(camera, renderer.domElement)



  scene.add(new THREE.AxesHelper(100))



  animate()



  function animate() {



  requestAnimationFrame(animate)



  renderer.render(scene, camera)



  }



  window.onresize = () => {



  renderer.setSize(box.clientWidth, box.clientHeight)



  camera.aspect = box.clientWidth / box.clientHeight



  camera.updateProjectionMatrix()



  }



  const urls = [0, 1, 2, 3, 4, 5].map(k => (FILE_HOST + 'files/sky/skyBox0/' + (k + 1) + '.png'));



  const textureCube = new THREE.CubeTextureLoader().load(urls);



  new GLTFLoader().load(FILE_HOST + 'models/whitebuild.glb', (gltf) => {



  const model = gltf.scene



  model.traverse((child) => {



  if (child.isMesh) {



  child.material.envMap = textureCube



  const { geometry } = child
              const edges = new THREE.EdgesGeometry(geometry)
              let lineGeometry = new LineSegmentsGeometry().fromEdgesGeometry(edges)
              const material = new LineMaterial({
                  color: 0xfcde8c,
                  linewidth: 2.5,
                  envMap: textureCube,
                  resolution: new THREE.Vector2(box.clientWidth, box.clientHeight)
              })



  const lines = new LineSegments2(lineGeometry, material)
              lines.computeLineDistances()
              lines.applyMatrix4(child.matrixWorld)



  scene.add(lines)
          }



  })


  `scene.add(model)
  })
  `

完整源码:GitHub

小结