3D热力图 ·Heatmap 3D· ▶ 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
- Canvas 动态纹理贴图
requestAnimationFrame渲染循环与resize自适应
效果说明
本案例演示3D热力图效果:用 Canvas 2D 绘制内容并实时映射为 Three.js 纹理;核心用到 ShaderMaterial、OrbitControls、Canvas。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()。 - CanvasTexture每帧或按需把 2D Canvas 内容上传 GPU,适合动态文字、图表、视频帧贴图。
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' /heatmap.js 自行安装module 方式引入 此处我为src 方式引入/
const DOM = document.getElementById('box')
const scene = new THREE.Scene()
const camera = new THREE.PerspectiveCamera(75, DOM.clientWidth / DOM.clientHeight, 0.1, 1000)
camera.position.set(0, 40, 40)
const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true })
renderer.setSize(DOM.clientWidth, DOM.clientHeight)
DOM.appendChild(renderer.domElement)
new OrbitControls(camera, renderer.domElement)
scene.add(new THREE.AxesHelper(500), new THREE.AmbientLight(0xffffff, 3))
window.onresize = () => {
renderer.setSize(DOM.clientWidth, DOM.clientHeight)
camera.aspect = DOM.clientWidth / DOM.clientHeight
camera.updateProjectionMatrix()
}
animate()
// 渲染 function animate() {
renderer.render(scene, camera)
requestAnimationFrame(animate)
}
const getRandom = (max, min) => Math.round((Math.random()(max - min + 1) + min)10) / 10
var heatmap = h337.create({ container: document.createElement('div'), width: 256, height: 256, blur: '0.8', radius: 10 });
var i = 0, max = 10, data = []; while (i < 2000) { data.push({ x: getRandom(1, 256), y: getRandom(1, 256), value: getRandom(1, 6) }); i++; }
heatmap.setData({ max: max, data: data });
const texture = new THREE.CanvasTexture(heatmap._renderer.canvas); const geometry = new THREE.PlaneGeometry(50, 50, 1000, 1000); geometry.rotateX(-Math.PI * 0.5);
const material = new THREE.ShaderMaterial({ uniforms: { heightMap: { value: texture }, heightRatio: { value: 5 } }, vertexShader:
uniform sampler2D heightMap; uniform float heightRatio; varying vec2 vUv; varying float hValue; varying vec3 cl; void main() { vUv = uv; vec3 pos = position; cl = texture2D(heightMap, vUv).rgb; hValue = texture2D(heightMap, vUv).r; pos.y = hValue * heightRatio; gl_Position = projectionMatrixmodelViewMatrixvec4(pos,1.0); }, fragmentShader:varying float hValue; varying vec3 cl; void main() { float v = abs(hValue - 1.); gl_FragColor = vec4(cl, .8 - v * v) ; }, transparent: true, })const mesh = new THREE.Mesh(geometry, material); scene.add(mesh);
new dat.GUI().add(mesh.material.uniforms.heightRatio, "value", 1, 15).name("heightRatio")完整源码:GitHub
小结
- 本文提供3D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