var ShaderExtras = {

	/* -------------------------------------------------------------------------
	//	Depth-of-field shader with bokeh
	//	ported from GLSL shader by Martins Upitis 
	//	http://artmartinsh.blogspot.com/2010/02/glsl-lens-blur-filter-with-bokeh.html
	 ------------------------------------------------------------------------- */
	
	'bokeh'	: {

	uniforms: { tColor:   { type: "t", value: 0, texture: null },
				tDepth:   { type: "t", value: 1, texture: null },
				focus:    { type: "f", value: 1.0 },
				aspect:   { type: "f", value: 1.0 },
				aperture: { type: "f", value: 0.025 },
				maxblur:  { type: "f", value: 1.0 },
			  },

	vertexShader: [

	"varying vec2 vUv;",

	"void main() {",
		
		"vUv = vec2( uv.x, 1.0 - uv.y );",
		"gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",
		
	"}"

	].join("\n"),

	fragmentShader: [

	"varying vec2 vUv;",
	
	"uniform sampler2D tColor;",
	"uniform sampler2D tDepth;",

	"uniform float maxblur;",  	// max blur amount
	"uniform float aperture;",	// aperture - bigger values for shallower depth of field
	
	"uniform float focus;",
	"uniform float aspect;",
	
	"void main() {",

	"vec2 aspectcorrect = vec2( 1.0, aspect );",

	"vec4 depth1 = texture2D( tDepth, vUv );",

	"float factor = depth1.x - focus;",
 
	"vec2 dofblur = vec2 ( clamp( factor * aperture, -maxblur, maxblur ) );",
	
	"vec2 dofblur9 = dofblur * 0.9;",
	"vec2 dofblur7 = dofblur * 0.7;",
	"vec2 dofblur4 = dofblur * 0.4;",

	"vec4 col = vec4( 0.0 );",

	"col += texture2D( tColor, vUv.xy );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,   0.4  ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.15,  0.37 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29,  0.29 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.37,  0.15 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.40,  0.0  ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.37, -0.15 ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29, -0.29 ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.15, -0.37 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,  -0.4  ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.15,  0.37 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29,  0.29 ) * aspectcorrect ) * dofblur );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.37,  0.15 ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.4,   0.0  ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.37, -0.15 ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29, -0.29 ) * aspectcorrect ) * dofblur );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.15, -0.37 ) * aspectcorrect ) * dofblur );",

	"col += texture2D( tColor, vUv.xy + ( vec2(  0.15,  0.37 ) * aspectcorrect ) * dofblur9 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.37,  0.15 ) * aspectcorrect ) * dofblur9 );",		
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.37, -0.15 ) * aspectcorrect ) * dofblur9 );",		
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.15, -0.37 ) * aspectcorrect ) * dofblur9 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.15,  0.37 ) * aspectcorrect ) * dofblur9 );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.37,  0.15 ) * aspectcorrect ) * dofblur9 );",		
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.37, -0.15 ) * aspectcorrect ) * dofblur9 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.15, -0.37 ) * aspectcorrect ) * dofblur9 );",	

	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29,  0.29 ) * aspectcorrect ) * dofblur7 );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.40,  0.0  ) * aspectcorrect ) * dofblur7 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29, -0.29 ) * aspectcorrect ) * dofblur7 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,  -0.4  ) * aspectcorrect ) * dofblur7 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29,  0.29 ) * aspectcorrect ) * dofblur7 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.4,   0.0  ) * aspectcorrect ) * dofblur7 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29, -0.29 ) * aspectcorrect ) * dofblur7 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,   0.4  ) * aspectcorrect ) * dofblur7 );",
		 
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29,  0.29 ) * aspectcorrect ) * dofblur4 );",
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.4,   0.0  ) * aspectcorrect ) * dofblur4 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.29, -0.29 ) * aspectcorrect ) * dofblur4 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,  -0.4  ) * aspectcorrect ) * dofblur4 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29,  0.29 ) * aspectcorrect ) * dofblur4 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.4,   0.0  ) * aspectcorrect ) * dofblur4 );",
	"col += texture2D( tColor, vUv.xy + ( vec2( -0.29, -0.29 ) * aspectcorrect ) * dofblur4 );",	
	"col += texture2D( tColor, vUv.xy + ( vec2(  0.0,   0.4  ) * aspectcorrect ) * dofblur4 );",

	"gl_FragColor = col / 41.0;",
	"gl_FragColor.a = 1.0;",
	
	"}"
	
	].join("\n")	
	
}

};
