溶解 ·Dissolve· ▶ 在线运行案例

• 案例合集：三维可视化功能案例（threehub.cn）
• 开源仓库github地址：https://github.com/z2586300277/three-cesium-examples
• 400个案例代码:网盘链接

你将学到什么

• ShaderMaterial 自定义着色器实现核心视觉效果
• OrbitControls 相机轨道交互
• requestAnimationFrame渲染循环与resize自适应

效果说明

本案例演示溶解效果：基于 WebGL 实现「溶解」可视化效果，附完整可运行源码；核心用到 ShaderMaterial、OrbitControls。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。
• ShaderMaterial通过uniforms+ 自定义 GLSL 控制逐像素/逐点效果；透明粒子常配合depthTest: false。
• OrbitControls提供轨道旋转/缩放；开启enableDamping后需在 animate 中controls.update()。

实现步骤

• 搭建 Scene、PerspectiveCamera、WebGLRenderer，挂载 canvas 并处理resize
• 定义 uniforms / onBeforeCompile 或 ShaderMaterial，编写 GLSL 与材质参数
• 创建 OrbitControls（及 Raycaster 等交互控件，若源码包含）
• 在requestAnimationFrame循环中更新状态并 render（Cesium 为viewer.render或自动渲染）

• 代码要点

  import * as THREE from 'three'
  import { OrbitControls } from "three/examples/jsm/controls/OrbitControls.js" import * as dat from 'dat.gui'
  /GUI/
  const gui = new dat.GUI()
  // Container const box = document.getElementById("box")
  // Scene const scene = new THREE.Scene()
  /**
  Loader
  */ const textureLoader = new THREE.TextureLoader()
  /Tex/ const dissolveTex = textureLoader.load(FILE_HOST + 'images/dissolve/dissolveTex.png') dissolveTex.colorSpace = THREE.SRGBColorSpace const dissolveRampTex = textureLoader.load(FILE_HOST + 'images/dissolve/dissolveRamp.png') dissolveRampTex.colorSpace = THREE.SRGBColorSpace const diffuseTex = textureLoader.load(FILE_HOST + 'images/dissolve/diffuse.png') diffuseTex.colorSpace = THREE.SRGBColorSpace
  /**
  Test mesh
  */ // Geometry const geometry = new THREE.PlaneGeometry(4, 3, 32, 32)
  // Material const shaderMaterial = new THREE.ShaderMaterial({ side: THREE.DoubleSide, vertexShader:/glsl/varying vec2 vUv; void main() { vUv = uv; vec4 modelPosition = modelMatrix * vec4(position, 1.); vec4 viewPosition = viewMatrix * modelPosition; vec4 projectedPosition = projectionMatrix * viewPosition; gl_Position = projectedPosition; }, fragmentShader:/glsl/uniform sampler2D uDissloveTex; uniform sampler2D uRamTex; uniform sampler2D uDiffuseTex; uniform float uClip; varying vec2 vUv; float customSmoothstep(float min, float max, float x) { return (x - min) / (max - min); }
  vec4 map(in vec4 value, in vec4 inMin, in vec4 inMax, in vec4 outMin, in vec4 outMax) { return outMin + (outMax - outMin) * (value - inMin) / (inMax - inMin); } void main() { vec4 DissloveTex = texture2D(uDissloveTex, vUv); DissloveTex = map(DissloveTex, vec4(0.), vec4(1.), vec4(0.1), vec4(1.));
  if((DissloveTex.r - uClip) < 0.) { discard; } float dissloveValue = clamp(customSmoothstep(uClip, uClip+.1, DissloveTex.r), 0., 1.); vec4 RamTex = texture2D(uRamTex, vec2(dissloveValue)); vec4 diffuse = texture2D(uDiffuseTex, vUv);
  vec3 color = vec3(clamp( diffuse.rgb + RamTex.rgb, 0., 1.));
  gl_FragColor = vec4(color, 1.0);
  #include #include }, uniforms: { uDissloveTex: new THREE.Uniform(dissolveTex), uRamTex: new THREE.Uniform(dissolveRampTex), uDiffuseTex: new THREE.Uniform(diffuseTex), uClip: new THREE.Uniform(0) } })
  gui.add(shaderMaterial.uniforms.uClip, 'value').min(0).max(1).step(0.01).name('Clip')
  // Mesh const mesh = new THREE.Mesh(geometry, shaderMaterial) scene.add(mesh)
  /**
  Sizes
  */ const sizes = { width: window.innerWidth, height: window.innerHeight }
  window.addEventListener('resize', () => { // Update sizes sizes.width = window.innerWidth sizes.height = window.innerHeight
  // Update camera camera.aspect = sizes.width / sizes.height camera.updateProjectionMatrix()
  // Update renderer renderer.setSize(sizes.width, sizes.height) renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2)) })
  /**
  Camera
  */ // Base camera const camera = new THREE.PerspectiveCamera(75, sizes.width / sizes.height, 0.1, 100) camera.position.set(0.25, - 0.25, 3.5) scene.add(camera)
  /**
  Renderer
  */ const renderer = new THREE.WebGLRenderer() renderer.antialias = true renderer.setSize(sizes.width, sizes.height) renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2)) renderer.outputColorSpace = THREE.SRGBColorSpace box.appendChild(renderer.domElement)
  // Controls const controls = new OrbitControls(camera, renderer.domElement) controls.enableDamping = true
  /**
  Animate
  */ const clock = new THREE.Clock()
  const tick = () => { const elapsedTime = clock.getElapsedTime()
  // Update controls controls.update()
  // Render renderer.render(scene, camera)
  // Call tick again on the next frame window.requestAnimationFrame(tick) }
  tick()

  完整源码：GitHub

  小结

  • 本文提供溶解完整 Three.js 源码与在线 Demo，建议先运行案例再改 uniform/参数做二次实验
  • 更多 Three.js 实战案例见 three-cesium-examples 合集 与 GitHub 开源仓库