text: /**
   * @author zz85 / http://www.lab4games.net/zz85/blog
   *
   * Two pass Gaussian blur filter (horizontal and vertical blur shaders)
   * - described in http://www.gamerendering.com/2008/10/11/gaussian-blur-filter-shader/
   *   and used in http://www.cake23.de/traveling-wavefronts-lit-up.html
   *
   * - 9 samples per pass
   * - standard deviation 2.7
   * - "h" and "v" parameters should be set to "1 / width" and "1 / height"
   */
  
  THREE.VerticalBlurShader = {
  
  	uniforms: {
  
  		"tDiffuse": { value: null },
  		"v":        { value: 1.0 / 512.0 }
  
  	},
  
  	vertexShader: [
  
  		"varying vec2 vUv;",
  
  		"void main() {",
  
  			"vUv = uv;",
  			"gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",
  
  		"}"
  
  	].join( "\n" ),
  
  	fragmentShader: [
  
  		"uniform sampler2D tDiffuse;",
  		"uniform float v;",
  
  		"varying vec2 vUv;",
  
  		"void main() {",
  
  			"vec4 sum = vec4( 0.0 );",
  
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y - 4.0 * v ) ) * 0.051;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y - 3.0 * v ) ) * 0.0918;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y - 2.0 * v ) ) * 0.12245;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y - 1.0 * v ) ) * 0.1531;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y ) ) * 0.1633;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y + 1.0 * v ) ) * 0.1531;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y + 2.0 * v ) ) * 0.12245;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y + 3.0 * v ) ) * 0.0918;",
  			"sum += texture2D( tDiffuse, vec2( vUv.x, vUv.y + 4.0 * v ) ) * 0.051;",
  
  			"gl_FragColor = sum;",
  
  		"}"
  
  	].join( "\n" )
  
  };
  