/**
 * @author alteredq / http://alteredqualia.com/
 *
 * Depth-of-field shader using mipmaps
 * - from Matt Handley @applmak
 * - requires power-of-2 sized render target with enabled mipmaps
 */

THREE.DOFMipMapShader = {

	uniforms: {

		"tColor":   { type: "t", value: null },
		"tDepth":   { type: "t", value: null },
		"focus":    { type: "f", value: 1.0 },
		"maxblur":  { type: "f", 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")

};