text: /**
   * @author alteredq / http://alteredqualia.com/
   *
   * Luminosity
   * http://en.wikipedia.org/wiki/Luminosity
   */
  
  
  
  var LuminosityShader = {
  
      uniforms: {
  
          "tDiffuse": { value: null }
  
      },
  
      vertexShader: [
  
          "varying vec2 vUv;",
  
          "void main() {",
  
          "    vUv = uv;",
  
          "    gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);",
  
          "}"
  
      ].join("\n"),
  
      fragmentShader: [
  
          "#include <common>",
  
          "uniform sampler2D tDiffuse;",
  
          "varying vec2 vUv;",
  
          "void main() {",
  
          "    vec4 texel = texture2D(tDiffuse, vUv);",
  
          "    float l = linearToRelativeLuminance(texel.rgb);",
  
          "    gl_FragColor = vec4(l, l, l, texel.w);",
  
          "}"
  
      ].join("\n")
  
  };
  
  export { LuminosityShader };
  