/**
 * Depth-of-field shader using mipmaps
 * - from Matt Handley @applmak
 * - requires power-of-2 sized render target with enabled mipmaps
 */

THREE.DOFMipMapShader = {

	uniforms: {

		'tColor': { value: null },
		'tDepth': { value: null },
		'focus': { value: 1.0 },
		'maxblur': { value: 1.0 }

	},

	vertexShader: [

		'varying vec2 vUv;',

		'void main() {',

		'	vUv = uv;',
		'	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );',

		'}'

	].join( '\n' ),

	fragmentShader: [

		'uniform float focus;',
		'uniform float maxblur;',

		'uniform sampler2D tColor;',
		'uniform sampler2D tDepth;',

		'varying vec2 vUv;',

		'void main() {',

		'	vec4 depth = texture2D( tDepth, vUv );',

		'	float factor = depth.x - focus;',

		'	vec4 col = texture2D( tColor, vUv, 2.0 * maxblur * abs( focus - depth.x ) );',

		'	gl_FragColor = col;',
		'	gl_FragColor.a = 1.0;',

		'}'

	].join( '\n' )

};
