bytev-charts/lib/plugin/three.js/examples/js/shaders/BrightnessContrastShader.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.BrightnessContrastShader: 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.");
/**
 * Brightness and contrast adjustment
 * https://github.com/evanw/glfx.js
 * brightness: -1 to 1 (-1 is solid black, 0 is no change, and 1 is solid white)
 * contrast: -1 to 1 (-1 is solid gray, 0 is no change, and 1 is maximum contrast)
 */

THREE.BrightnessContrastShader = {
  uniforms: {
    "tDiffuse": {
      value: null
    },
    "brightness": {
      value: 0
    },
    "contrast": {
      value: 0
    }
  },
  vertexShader: ["varying vec2 vUv;", "void main() {", "	vUv = uv;", "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );", "}"].join("\n"),
  fragmentShader: ["uniform sampler2D tDiffuse;", "uniform float brightness;", "uniform float contrast;", "varying vec2 vUv;", "void main() {", "	gl_FragColor = texture2D( tDiffuse, vUv );", "	gl_FragColor.rgb += brightness;", "	if (contrast > 0.0) {", "		gl_FragColor.rgb = (gl_FragColor.rgb - 0.5) / (1.0 - contrast) + 0.5;", "	} else {", "		gl_FragColor.rgb = (gl_FragColor.rgb - 0.5) * (1.0 + contrast) + 0.5;", "	}", "}"].join("\n")
};