Three.js 自定义遮罩通道教程

自定义遮罩通道 ·Custom Mask· ▶ 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-examples400个案例代码:网盘链接你将学到什么EffectComposer 多 Pass 后期处理管线OrbitControls 相机轨道交互自定义 ShaderPass 调色/特效requestAnimationFrame渲染循环与resize自适应效果说明本案例演示自定义遮罩通道效果原场景渲染后经 EffectComposer 叠加 Bloom/模糊等全屏后期核心用到 EffectComposer、OrbitControls、自定义。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。EffectComposer以多 Pass 链式渲染RenderPass → 特效 Pass → 输出屏幕替代直接renderer.render。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 与材质参数组装 EffectComposer Pass 链在 animate 中调用composer.render()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 renderCesium 为viewer.render或自动渲染代码要点import * as THREE from threeimport { OrbitControls } from three/examples/jsm/controls/OrbitControls.js import { ShaderPass } from three/examples/jsm/postprocessing/ShaderPass.js import { EffectComposer } from three/examples/jsm/postprocessing/EffectComposer.js import { RenderPass } from three/examples/jsm/postprocessing/RenderPass.jsclass ScreenMaskPass extends ShaderPass {constructor() {super({name: ScreenMaskShader,uniforms: { tDiffuse: { value: null }, opacity: { value: 1.0 }, intensity: { value: 2.0 }, maskColor: { value: new THREE.Color(1, 1, 1) }, R: { value: 0.1 }, sr: { value: 1.2 } },vertexShader:varying vec2 vUv; void main() { vUv uv; gl_Position projectionMatrixmodelViewMatrixvec4( position, 1.0 ); },fragmentShader:uniform float opacity; uniform float intensity; uniform sampler2D tDiffuse; uniform vec3 maskColor; uniform float R; uniform float sr; varying vec2 vUv; void main() { // 阴影颜色 vec4 texel texture2D( tDiffuse, vUv ); // 距离中心的距离 float dist sqrt((vUv.x-0.5)(vUv.x-0.5)(vUv.y-0.5)(vUv.y-0.5)); // 渐变, sr 是开始黑色参数 float rr (sr - smoothstep(R, R 0.5, dist)); // 叠加黑色 texel vec4(maskColorrr * vec3(intensity,intensity,intensity), 1.0); gl_FragColor opacity * texel; }})}}const box document.getElementById(box)const scene new THREE.Scene()const camera new THREE.PerspectiveCamera(75, box.clientWidth / box.clientHeight, 0.1, 1000)camera.position.set(0, 2, 8)const renderer new THREE.WebGLRenderer()renderer.setSize(box.clientWidth, box.clientHeight)box.appendChild(renderer.domElement)new OrbitControls(camera, renderer.domElement)const composer new EffectComposer(renderer)const renderPass new RenderPass(scene, camera)composer.addPass(renderPass)const screenMaskPass new ScreenMaskPass()composer.addPass(screenMaskPass)scene.add(new THREE.AxesHelper(500), new THREE.GridHelper(500, 50))animate()function animate() {requestAnimationFrame(animate)composer.render()}window.onresize () {renderer.setSize(box.clientWidth, box.clientHeight)camera.aspect box.clientWidth / box.clientHeightcamera.updateProjectionMatrix()}// 文件地址 const urls [0, 1, 2, 3, 4, 5].map(k (https://z2586300277.github.io/three-editor/dist/files/scene/skyBox0/ (k 1) .png));const textureCube new THREE.CubeTextureLoader().load(urls);scene.background textureCube;完整源码GitHub小结本文提供自定义遮罩通道完整 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