场景雪 ·sceneSnowEffect· ▶ 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ShaderMaterial 自定义着色器实现核心视觉效果OrbitControls 相机轨道交互THREE.Points 粒子点渲染glTF/Draco 模型加载与优化BufferGeometry 自定义顶点/索引数据requestAnimationFrame渲染循环与resize自适应效果说明本案例演示场景雪效果基于 WebGL 实现「场景雪」可视化效果附完整可运行源码核心用到 ShaderMaterial、OrbitControls、THREE.Points。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()。THREE.Points将每个顶点渲染为可控大小的粒子可用自定义 attribute如u_index驱动片元/顶点动画。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 renderCesium 为viewer.render或自动渲染代码要点import * as THREE from three;import Stats from three/examples/jsm/libs/stats.module.js; import {GLTFLoader} from three/examples/jsm/loaders/GLTFLoader.js; import {OrbitControls} from three/examples/jsm/controls/OrbitControls.js import {DRACOLoader} from three/examples/jsm/loaders/DRACOLoader.js; import {GUI} from three/addons/libs/lil-gui.module.min.js console.log(Three.js 版本:, THREE.REVISION); const gui new GUI() const size { width: window.innerWidth, height: window.innerHeight, maxX: 20, minX: -20, maxY: 20, minY: 0, maxZ: 20, minZ: -20 } const vertices [] const offset [] let particleCount1000 const geometry new THREE.BufferGeometry() for (let i 0; i particleCount; i) { const x 1000 * (Math.random() - 0.5) const y 600 * Math.random() const z 1000 * (Math.random() - 0.5)vertices.push(x, y, z) offset.push(Math.random() - 0.5, 0, Math.random() - 0.5) } geometry.setAttribute(position, new THREE.Float32BufferAttribute(vertices, 3)) /*纹理/ const texture new THREE.TextureLoader().load(HOST files/images/snow.png) const pointMesh new THREE.Points( geometry, new THREE.PointsMaterial({ size: 5, depthTest: true, map: texture, transparent: true, blending: THREE.AdditiveBlending, opacity: 0.8, sizeAttenuation: true }) ) // 创建一个控制对象 const params { snowEnabled: true, // 默认值为true snowAmount: 0.7 };//后处理管理对象 const postprocessing {}// 添加GUI控制 const folder gui.addFolder(调节参数); // 添加checkbox folder.add(params, snowEnabled).name(启用雪效果).onChange((value) { params.snowEnabled value; }); folder.add(params, snowAmount, 0, 1, 0.01).name(雪量).onChange((value) { postprocessing.finalMaterial.uniforms.snowAmount.value value; });// 初始化场景、相机、渲染器 const scene new THREE.Scene(); const camera new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 10000); camera.position.set(0, 100, 300); // 明确设置相机初始位置 camera.lookAt(0, 0, 0); // 看向场景中心 scene.add(camera); const renderer new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true }); renderer.outputColorSpace srgb renderer.setSize(window.innerWidth, window.innerHeight); renderer.setClearColor(0x000000); document.body.appendChild(renderer.domElement);const ambientLight new THREE.AmbientLight(#fff, 2); scene.add(ambientLight); scene.add(pointMesh); // 添加性能监控 const stats new Stats(); document.body.appendChild(stats.dom); // 初始化控制器 const controls new OrbitControls(camera, renderer.domElement); controls.enableDamping true;const gltfLoader new GLTFLoader() const dracoLoader new DRACOLoader() dracoLoader.setDecoderPath(FILE_HOST js/three/draco/) gltfLoader.setDRACOLoader(dracoLoader) //加载模型 使用私有对象存储带宽较低耐心等待一下 // http://app.foxicle.xyz:9000/public-bucket/model/city/index.gltf gltfLoader.load(FILE_HOST models/modern_city.glb, (gltf) { gltf.scene.scale.set(0.01, 0.01, 0.01); scene.add(gltf.scene) }, (event) { const percentComplete (event.loaded / event.total * 100).toFixed(2); console.log(模型加载进度: ${percentComplete}%); });initPostprocessing(window.innerWidth, window.innerHeight)function updatePoints(){ for (let i 1; i vertices.length; i 3) { vertices[i] - 0.5 vertices[i - 1] - offset[i - 1] vertices[i 1] - offset[i 1] if (vertices[i] 0) { vertices[i] 600 }if (vertices[i - 1] size.minX || vertices[i - 1] size.maxX) { offset[i - 1] -offset[i - 1] }if (vertices[i 1] size.minZ || vertices[i 1] size.maxZ) { offset[i 1] -offset[i 1] } }pointMesh.geometry.setAttribute(position, new THREE.Float32BufferAttribute(vertices, 3)) }// 动画渲染 function animate() { requestAnimationFrame(animate)if (params.snowEnabled) { pointMesh.visibletrue updatePoints() scene.overrideMaterial null //写入原场景渲染图 renderer.setRenderTarget(postprocessing.difusse) renderer.render(scene, camera) // //将定点数据 法相数据存入通道 scene.overrideMaterial postprocessing.gBufferPass renderer.setRenderTarget(postprocessing.gBuffer) renderer.render(scene, camera) renderer.setRenderTarget(null) renderer.render(postprocessing.scene, postprocessing.camera); } else { pointMesh.visiblefalse scene.overrideMaterial null renderer.setRenderTarget(null) renderer.render(scene, camera) } stats.update() controls.update() }animate();/**核心逻辑,备注:对场景中部分透明物体渲染存在错误,需要额外处理,这里主要是提供思路param renderTargetWidthparam renderTargetHeight*/ function initPostprocessing(renderTargetWidth, renderTargetHeight) { postprocessing.scene new THREE.Scene(); postprocessing.camera new THREE.OrthographicCamera(-1, 1, 1, -1, 0, 1); postprocessing.scene.add(postprocessing.camera); //漫射 postprocessing.difusse new THREE.WebGLRenderTarget(renderTargetWidth, renderTargetHeight, { format: THREE.RGBAFormat, type: THREE.FloatType, colorSpace: THREE.SRGBColorSpace, depthBuffer: true, samples: 4, minFilter: THREE.NearestFilter, magFilter: THREE.NearestFilter, stencilBuffer: false, }) postprocessing.gBuffer new THREE.WebGLRenderTarget(renderTargetWidth, renderTargetHeight, { format: THREE.RGBAFormat, // 使用 RGBAFormat 确保有 alpha 通道 type: THREE.FloatType, // 使用 FloatType 以确保存储精度 depthBuffer: true, // 确保有深度缓冲 samples: 4, count: 2 })// G-BUFFER 管线 postprocessing.gBufferPass new THREE.ShaderMaterial({ vertexShader:out vec3 vNormal; out vec3 vWorldPosition; void main() { vNormal normal; // 计算顶点的世界坐标模型矩阵将顶点从模型空间转换到世界空间 vec4 worldPosition modelMatrix * vec4(position, 1.0); vWorldPosition worldPosition.xyz; gl_Position projectionMatrixviewMatrixworldPosition; }, fragmentShader:in vec3 vNormal; in vec3 vWorldPosition; layout(location 0) out vec4 gPosition; layout(location 1) out vec4 gNormal; void main() { gPosition vec4(vWorldPosition, 1.0); gNormal normalize(vec4(vNormal, 1.0)); }, glslVersion: 300 es })postprocessing.finalMaterial new THREE.ShaderMaterial({ defines: { EMISSIVE: 10, }, vertexShader:out vec2 vUv; void main() { vUv uv; gl_Position projectionMatrixviewMatrixmodelMatrix * vec4(position, 1.0); }, fragmentShader:precision highp float; precision highp int; uniform sampler2D tPosition; uniform sampler2D tNormal; uniform sampler2D tDiffuse; uniform vec2 resolution; uniform float time; uniform vec3 uCameraPosition; uniform float snowAmount; uniform float snowNoise; uniform float snowEdge; in vec2 vUv; out vec4 fragColor; // 改进的噪声函数 float rand(vec2 co) { return fract(sin(dot(co.xy, vec2(12.9898, 78.233))) * 43758.5453); } float noise(vec2 p) { vec2 ip floor(p); vec2 fp fract(p); float a rand(ip); float b rand(ip vec2(1.0, 0.0)); float c rand(ip vec2(0.0, 1.0)); float d rand(ip vec2(1.0, 1.0)); vec2 u fpfp(3.0 - 2.0 * fp); return mix(a, b, u.x) (c - a)u.y(1.0 - u.x) (d - b)u.xu.y; } float fbm(vec2 p) { float total 0.0; float amplitude 1.0; for (int i 0; i 4; i) { total noise(p) * amplitude; p * 2.0; amplitude * 0.5; } return total; } void main() { // 从G-Buffer读取数据 vec3 position texture(tPosition, vUv).rgb; vec3 normal normalize(texture(tNormal, vUv).rgb); vec4 diffuseSample texture(tDiffuse, vUv); vec3 diffuse diffuseSample.rgb; if (diffuseSample.a0.01) discard; // 计算积雪因子 - 基于法线Y分量 float snowFactor max(0.0, dot(normal, vec3(0.0, 1.0, 0.0))); snowFactor pow(snowFactor, 3.0);// 增强对比度 // 添加噪声效果 vec2 noiseCoord position.xz0.5 vec2(time0.05); float noiseVal fbm(noiseCoord); snowFactor clamp(snowFactor (noiseVal - 0.5) * snowNoise, 0.0, 1.0); snowFactor * snowAmount; // 边缘积雪增强 vec2 texelSize 1.0 / resolution; float depthCenter texture(tPosition, vUv).z; float depthRight texture(tPosition, vUv vec2(texelSize.x, 0.0)).z; float depthBottom texture(tPosition, vUv vec2(0.0, texelSize.y)).z; float depthDiff max(abs(depthCenter - depthRight), abs(depthCenter - depthBottom)); snowFactor max(snowFactor, smoothstep(0.0, 0.1, depthDiff) * snowEdge); // 雪的颜色 - 使用更纯的白色减少蓝色调 vec3 snowColor mix(vec3(0.95, 0.96, 0.98), vec3(1.0), noiseVal * 0.2); // 最终颜色混合 - 使用更激进的混合 vec3 finalColor mix(diffuse, snowColor, smoothstep(0.3, 0.7, snowFactor)); // 修改高光效果 - 更柔和、更白的高光 if (snowFactor 0.3) { vec3 lightDir normalize(vec3(1.0, 1.0, 1.0)); vec3 viewDir normalize(uCameraPosition - position); vec3 halfDir normalize(lightDir viewDir); float spec pow(max(0.0, dot(normal, halfDir)), 32.0); // 使用白色高光强度降低 finalColor spec0.1vec3(1.0) * snowFactor; } // 提高整体亮度 finalColor mix(finalColor, vec3(1.0), snowFactor * 0.3); fragColor vec4(finalColor, 1.0); }, glslVersion: 300 es, uniforms: { tPosition: {value: postprocessing.gBuffer.textures[0]}, tNormal: {value: postprocessing.gBuffer.textures[1]}, tDiffuse: {value: postprocessing.difusse.texture}, resolution: {value: new THREE.Vector2(window.innerWidth, window.innerHeight)}, time: {value: 0}, uCameraPosition: {value: new THREE.Vector3()}, // 对应着色器中的重命名 snowAmount: {value: 0.7}, snowNoise: {value: 0.3}, snowEdge: {value: 0.5} }, }); postprocessing.quad new THREE.Mesh( new THREE.PlaneGeometry(2.0, 2.0), postprocessing.finalMaterial ); postprocessing.scene.add(postprocessing.quad);}// 窗口大小调整 window.addEventListener(resize, onWindowResize, false);function onWindowResize() { camera.aspect window.innerWidth / window.innerHeight; camera.updateProjectionMatrix(); renderer.setSize(window.innerWidth, window.innerHeight); }完整源码GitHub小结本文提供场景雪完整 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