three.js/examples/js/shaders/FocusShader.js

( function () {

	/**
 * Focus shader
 * based on PaintEffect postprocess from ro.me
 * http://code.google.com/p/3-dreams-of-black/source/browse/deploy/js/effects/PaintEffect.js
 */
	var FocusShader = {
		uniforms: {
			'tDiffuse': {
				value: null
			},
			'screenWidth': {
				value: 1024
			},
			'screenHeight': {
				value: 1024
			},
			'sampleDistance': {
				value: 0.94
			},
			'waveFactor': {
				value: 0.00125
			}
		},
		vertexShader: [ 'varying vec2 vUv;', 'void main() {', '	vUv = uv;', '	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );', '}' ].join( '\n' ),
		fragmentShader: [ 'uniform float screenWidth;', 'uniform float screenHeight;', 'uniform float sampleDistance;', 'uniform float waveFactor;', 'uniform sampler2D tDiffuse;', 'varying vec2 vUv;', 'void main() {', '	vec4 color, org, tmp, add;', '	float sample_dist, f;', '	vec2 vin;', '	vec2 uv = vUv;', '	add = color = org = texture2D( tDiffuse, uv );', '	vin = ( uv - vec2( 0.5 ) ) * vec2( 1.4 );', '	sample_dist = dot( vin, vin ) * 2.0;', '	f = ( waveFactor * 100.0 + sample_dist ) * sampleDistance * 4.0;', '	vec2 sampleSize = vec2(	1.0 / screenWidth, 1.0 / screenHeight ) * vec2( f );', '	add += tmp = texture2D( tDiffuse, uv + vec2( 0.111964, 0.993712 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( 0.846724, 0.532032 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( 0.943883, -0.330279 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( 0.330279, -0.943883 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( -0.532032, -0.846724 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( -0.993712, -0.111964 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	add += tmp = texture2D( tDiffuse, uv + vec2( -0.707107, 0.707107 ) * sampleSize );', '	if( tmp.b < color.b ) color = tmp;', '	color = color * vec4( 2.0 ) - ( add / vec4( 8.0 ) );', '	color = color + ( add / vec4( 8.0 ) - color ) * ( vec4( 1.0 ) - vec4( sample_dist * 0.5 ) );', '	gl_FragColor = vec4( color.rgb * color.rgb * vec3( 0.95 ) + color.rgb, 1.0 );', '}' ].join( '\n' )
	};

	THREE.FocusShader = FocusShader;

} )();