模型热力图 ·Model Heatmap· ▶ 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模型热力图效果基于 WebGL 实现「模型热力图」可视化效果附完整可运行源码核心用到 ShaderMaterial、OrbitControls、glTF/Draco。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 threeimport { OrbitControls } from three/examples/jsm/controls/OrbitControls.js import { GLTFLoader } from three/examples/jsm/loaders/GLTFLoader.js import { GUI } from three/examples/jsm/libs/lil-gui.module.min.jsconst 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(5, 5, 5)const renderer new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true })renderer.setSize(box.clientWidth, box.clientHeight)box.appendChild(renderer.domElement)new OrbitControls(camera, renderer.domElement)window.onresize () {renderer.setSize(box.clientWidth, box.clientHeight)camera.aspect box.clientWidth / box.clientHeightcamera.updateProjectionMatrix()}animate()function animate() {requestAnimationFrame(animate)renderer.render(scene, camera)}scene.add(new THREE.AmbientLight(0xffffff, 3))new GLTFLoader().load(https://z2586300277.github.io/three-editor/dist/files/resource/datacenter.glb,gltf {scene.add(gltf.scene)callModel(gltf.scene)})let model nullfunction callModel(e) { model e const box3 new THREE.Box3().setFromObject(model) const { min, max } box3 // 根据模型的包围盒 固定y 生成一个平面 const p1 new THREE.Vector3(min.x, 0, min.z) const p2 new THREE.Vector3(min.x, 0, max.z) const p3 new THREE.Vector3(max.x, 0, max.z) const p4 new THREE.Vector3(max.x, 0, min.z) const geometry new THREE.BufferGeometry() const vertices new Float32Array([ p1.x, p1.y, p1.z, p2.x, p2.y, p2.z, p3.x, p3.y, p3.z, p4.x, p4.y, p4.z, ]) geometry.setAttribute(position, new THREE.BufferAttribute(vertices, 3)) geometry.setIndex([0, 1, 2, 0, 2, 3]) geometry.attributes.uv new THREE.Float32BufferAttribute([ 0, 0, 0, 1, 1, 1, 1, 0 ], 2) geometry.computeVertexNormals()let list []model.traverse(i { if (i.isMesh) { i.material.transparent true i.material.opacity 0.5 i.isMesh list.push(i.name) } })// list 随机获取 5 - 10 个名字形成新的数组 const randomNum Math.floor(Math.random() * (10 - 5 1)) 5 list list.sort(() Math.random() - 0.5).slice(0, randomNum)let w max.x - min.x let h max.z - min.z/热力图实现/ const arr list.map(i { const obj model.getObjectByName(i) const worldPosition new THREE.Vector3() obj.getWorldPosition(worldPosition) return [(worldPosition.x - min.x) / w, (worldPosition.z - min.z) / h, Math.random() * 10] }).flat() const uniforms1 { HEAT_MAX: { value: 10, type: number, unit: float }, PointRadius: { value: 0.2, type: number, unit: float }, intensity: { value: 3, type: number, unit: float }, PointsCount: { value: arr.length, type: number-array, unit: int }, c1: { value: new THREE.Color(green), type: color, unit: vec3 }, // 蓝色 c2: { value: new THREE.Color(red), type: color, unit: vec3 }, // 红色 uvY: { value: 1, type: number, unit: float }, uvX: { value: 1, type: number, unit: float }, opacity: { value: 0.6, type: number, unit: float }, // 稍微降低整体不透明度 edgeFalloff: { value: 2.0, type: number, unit: float } // 边缘衰减参数 }const gui new GUI() gui.add(uniforms1.HEAT_MAX, value, 0, 10).name(HEAT_MAX) gui.add(uniforms1.PointRadius, value, 0, 1).name(PointRadius) gui.add(uniforms1.intensity, value, 0, 10).name(intensity) gui.add(uniforms1.uvY, value, 0, 1).name(uvY) gui.add(uniforms1.uvX, value, 0, 1).name(uvX) gui.add(uniforms1.opacity, value, 0, 1).name(opacity) gui.add(uniforms1.edgeFalloff, value, 0.1, 5).name(边缘衰减) gui.addColor(uniforms1.c1, value).name(冷色) gui.addColor(uniforms1.c2, value).name(热色)const uniforms2 { Points: { value: arr, type: vec3-array, unit: vec3 } }const uniforms { ...uniforms1, ...uniforms2 } const vertexShader varying vec2 vUv; void main() { vUv uv; gl_Position projectionMatrixmodelViewMatrixvec4(position, 1.0); }const getFragmentShader () precision highp float;\n varying vec2 vUv; \n Object.keys(uniforms1).map(i uniform uniforms1[i].unit i ;) .join(\n)\nuniform vec3 Points[uniforms1.PointsCount.value ];vec3 gradient(float w, vec2 uv) { // 平滑过渡的热力图颜色 w pow(clamp(w, 0., 1.), 0.8); return mix(c1, c2, w); } void main() { vec2 uv vUv; uv.xy * vec2(uvX, uvY); float d 0.; // 计算热度值 for (int i 0; i PointsCount; i) { vec3 v Points[i]; float intensity v.z / HEAT_MAX; float dist length(uv - v.xy); float pd (1. - dist / PointRadius) * intensity; d pow(max(0., pd), 1.5); } // 计算边缘衰减因子 float edgeFactor 1.0; vec2 center vec2(0.5, 0.5); float distFromCenter length(uv - center); // 在UV坐标的边缘部分应用透明度衰减 float edgeStart 0.4; if (distFromCenter edgeStart) { edgeFactor 1.0 - pow((distFromCenter - edgeStart) / (0.5 - edgeStart), edgeFalloff); } // 确保边缘的透明度为0 edgeFactor clamp(edgeFactor, 0.0, 1.0); // 应用热力颜色和透明度 vec3 heatColor gradient(d, uv); float alpha min(opacityedgeFactor, d 0.05 ? 1.0 : d20.0); gl_FragColor vec4(heatColor * vec3(intensity,intensity,intensity), alpha); }const shaderMaterial new THREE.ShaderMaterial({ uniforms, vertexShader, fragmentShader: getFragmentShader(), side: THREE.DoubleSide, depthWrite: false, depthTest: false, transparent: true, blending: THREE.AdditiveBlending // 使用加法混合使热力图更具光晕效果 }) const mesh new THREE.Mesh(geometry, shaderMaterial) scene.add(mesh) }完整源码GitHub小结本文提供模型热力图完整 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
