text: //This file is automatically rebuilt by the Cesium build process.
  export default "/**\n\
   * Compositing for Weighted Blended Order-Independent Transparency. See:\n\
   * - http://jcgt.org/published/0002/02/09/\n\
   * - http://casual-effects.blogspot.com/2014/03/weighted-blended-order-independent.html\n\
   */\n\
  \n\
  uniform sampler2D u_opaque;\n\
  uniform sampler2D u_accumulation;\n\
  uniform sampler2D u_revealage;\n\
  \n\
  varying vec2 v_textureCoordinates;\n\
  \n\
  void main()\n\
  {\n\
      vec4 opaque = texture2D(u_opaque, v_textureCoordinates);\n\
      vec4 accum = texture2D(u_accumulation, v_textureCoordinates);\n\
      float r = texture2D(u_revealage, v_textureCoordinates).r;\n\
  \n\
  #ifdef MRT\n\
      vec4 transparent = vec4(accum.rgb / clamp(r, 1e-4, 5e4), accum.a);\n\
  #else\n\
      vec4 transparent = vec4(accum.rgb / clamp(accum.a, 1e-4, 5e4), r);\n\
  #endif\n\
  \n\
      gl_FragColor = (1.0 - transparent.a) * transparent + transparent.a * opaque;\n\
  \n\
      if (opaque != czm_backgroundColor)\n\
      {\n\
          gl_FragColor.a = 1.0;\n\
      }\n\
  }\n\
  ";
  