three.js 使用 heatmap 实现 3d 热力图

先上效果图：

闲来无事想随便做做3d的东西，正好想到之前有个3d热力图的需求，后面没做被砍了，今天正好来做一下。在网上搜了搜参看了一些其他人的成果，最后还是弄出来了。记录一下，避免以后找不到。

单独定义一个ts 文件 ，导出    TDHeatMap  方法，接收了参数，但是没用，可以自己封装一下参数。

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import * as THREE from 'three';   export const TDHeatMap = (data: any) => {     // 热力图     var heatmap = h337.create({         container: document.getElementById('heatmap')     });     var len = 100;     var width = 300;     var height = 300;     var points = [];     var max = 0;     while (len--) {         var val = Math.floor(Math.random() * 100);         max = Math.max(max, val);         var point = {             x: Math.floor(Math.random() * width),             y: Math.floor(Math.random() * height),             value: val         };         points.push(point);     }     heatmap.setData({         max: max,         data: points     });     // 灰度图     var greymap = h337.create({         container: document.getElementById('greymap'),         gradient: {             '0': 'black',             '1.0': 'white'         }     });       greymap.setData({         max: max,         data: points     });     let heatMapMaterial = new THREE.ShaderMaterial({         transparent: true,         vertexShader: `varying vec2 vUv;         uniform float Zscale;         uniform sampler2D greyMap;         void main() {          vUv = uv;         vec4 frgColor = texture2D(greyMap, uv);//获取灰度图点位信息         float height = Zscale * frgColor.a;//通过灰度图的rgb*需要设置的高度计算出热力图每个点位最终在z轴高度         vec3 transformed = vec3( position.x, position.y, height);//重新组装点坐标         gl_Position = projectionMatrix * modelViewMatrix * vec4(transformed, 1.0);//渲染点位                 }       `,         fragmentShader: `varying vec2 vUv;         uniform sampler2D heatMap;//热力图         uniform vec3 u_color;//基础颜色         uniform float u_opacity; // 透明度         void main() {           //vec4 alphaColor = texture2D(heatMap, vUv);           // gl_FragColor = alphaColor;            gl_FragColor = vec4(u_color, u_opacity) * texture2D(heatMap, vUv);//把热力图颜色和透明度进行渲染         }`,         uniforms: {             'heatMap': {                 value: { value: undefined }             },             'greyMap': {                 value: { value: undefined }             },             Zscale: { value: 100.0 }, // 高度参数             u_color: {                 value: new THREE.Color('rgb(255, 255, 255)')             },             u_opacity: {                 value: 1.0             }         }     });     let texture = new THREE.Texture(heatmap._config.container.children[0]);     texture.needsUpdate = true;     let texture2 = new THREE.Texture(greymap._config.container.children[0]);     texture2.needsUpdate = true;     heatMapMaterial.uniforms.heatMap.value = texture;     heatMapMaterial.side = THREE.DoubleSide; // 双面渲染     heatMapMaterial.uniforms.greyMap.value = texture2     const heatMapModel = new THREE.PlaneBufferGeometry(800, 800, 300, 300) // 3d热力图大小，及分块数量     let heatMapPlane = new THREE.Mesh(heatMapModel, heatMapMaterial)     heatMapPlane.rotation.set(-Math.PI / 2, 0, 0);     heatMapPlane.position.set(200, 0, 0);  //  3d热力图中心点位置     return heatMapPlane }

　　使用

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1 2	const HeatMesh = TDHeatMap(''); Three.threeExample.lightEfficiencyGroup.add(HeatMesh); // 添加到场景中。

　　需要引入  heatmap.js 文件

文件如下，或者自己去网上找

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/*  * heatmap.js v2.0.2 | JavaScript Heatmap Library  *  * Copyright 2008-2016 Patrick Wied <heatmapjs@patrick-wied.at> - All rights reserved.  * Dual licensed under MIT and Beerware license  *  * :: 2016-02-04 21:25  */ (function(a,b,c){if(typeof module!=="undefined"&&module.exports){module.exports=c()}else if(typeof define==="function"&&define.amd){define(c)}else{b[a]=c()}})("h337",this,function(){var a={defaultRadius:40,defaultRenderer:"canvas2d",defaultGradient:{.25:"rgb(0,0,255)",.55:"rgb(0,255,0)",.85:"yellow",1:"rgb(255,0,0)"},defaultMaxOpacity:1,defaultMinOpacity:0,defaultBlur:.85,defaultXField:"x",defaultYField:"y",defaultValueField:"value",plugins:{}};var b=function h(){var b=function d(a){this._coordinator={};this._data=[];this._radi=[];this._min=0;this._max=1;this._xField=a["xField"]||a.defaultXField;this._yField=a["yField"]||a.defaultYField;this._valueField=a["valueField"]||a.defaultValueField;if(a["radius"]){this._cfgRadius=a["radius"]}};var 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我一般不讲代码，只有部分注释，需要的同志可以自己看，源码也比较少，可以自己理解一下，很简单，