bytev-charts/lib/plugin/three.js/examples/js/shaders/FocusShader.js

基于echarts和JavaScript及ES6封装的一个可以直接调用的图表组件库，内置主题设计，简单快捷，且支持用户自定义配置； npm 安装方式: npm install bytev-charts 若启动提示还需额外install插件,则运行 npm install @babel/runtime-corejs2 即可;

import "core-js/modules/es.array.join.js";
console.warn("THREE.FocusShader: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/#manual/en/introduction/Installation.");
/**
 * Focus shader
 * based on PaintEffect postprocess from ro.me
 * http://code.google.com/p/3-dreams-of-black/source/browse/deploy/js/effects/PaintEffect.js
 */

THREE.FocusShader = {
  uniforms: {
    "tDiffuse": {
      value: null
    },
    "screenWidth": {
      value: 1024
    },
    "screenHeight": {
      value: 1024
    },
    "sampleDistance": {
      value: 0.94
    },
    "waveFactor": {
      value: 0.00125
    }
  },
  vertexShader: ["varying vec2 vUv;", "void main() {", "	vUv = uv;", "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );", "}"].join("\n"),
  fragmentShader: ["uniform float screenWidth;", "uniform float screenHeight;", "uniform float sampleDistance;", "uniform float waveFactor;", "uniform sampler2D tDiffuse;", "varying vec2 vUv;", "void main() {", "	vec4 color, org, tmp, add;", "	float sample_dist, f;", "	vec2 vin;", "	vec2 uv = vUv;", "	add = color = org = texture2D( tDiffuse, uv );", "	vin = ( uv - vec2( 0.5 ) ) * vec2( 1.4 );", "	sample_dist = dot( vin, vin ) * 2.0;", "	f = ( waveFactor * 100.0 + sample_dist ) * sampleDistance * 4.0;", "	vec2 sampleSize = vec2(  1.0 / screenWidth, 1.0 / screenHeight ) * vec2( f );", "	add += tmp = texture2D( tDiffuse, uv + vec2( 0.111964, 0.993712 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( 0.846724, 0.532032 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( 0.943883, -0.330279 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( 0.330279, -0.943883 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( -0.532032, -0.846724 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( -0.993712, -0.111964 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	add += tmp = texture2D( tDiffuse, uv + vec2( -0.707107, 0.707107 ) * sampleSize );", "	if( tmp.b < color.b ) color = tmp;", "	color = color * vec4( 2.0 ) - ( add / vec4( 8.0 ) );", "	color = color + ( add / vec4( 8.0 ) - color ) * ( vec4( 1.0 ) - vec4( sample_dist * 0.5 ) );", "	gl_FragColor = vec4( color.rgb * color.rgb * vec3( 0.95 ) + color.rgb, 1.0 );", "}"].join("\n")
};