Improved anaglyph encoding.

[: This' how the cool cats do it these days :]

examples/js/effects/AnaglyphEffect.js

@@ -2,10 +2,31 @@
  * @author mrdoob / http://mrdoob.com/
  * @author marklundin / http://mark-lundin.com/
  * @author alteredq / http://alteredqualia.com/
+ * @author tschw
  */
 
 THREE.AnaglyphEffect = function ( renderer, width, height ) {
 
+	// Matrices generated with angler.js https://github.com/tschw/angler.js/
+	// (in column-major element order, as accepted by WebGL)
+
+	this.colorMatrixLeft = new THREE.Matrix3().set(
+
+			1.0671679973602295, 	-0.0016435992438346148,		 0.0001777536963345483, // r out
+			-0.028107794001698494,	-0.00019593400065787137,	-0.0002875397040043026, // g out
+			-0.04279090091586113,	 0.000015809757314855233,	-0.00024287120322696865 // b out
+	);
+
+	//		red						green 						blue  						in
+
+	this.colorMatrixRight = new THREE.Matrix3().set(
+
+			-0.0355340838432312,	-0.06440307199954987,		 0.018319187685847282,	// r out
+			-0.10269022732973099,	 0.8079727292060852,		-0.04835830628871918,	// g out
+			0.0001224992738571018,	-0.009558862075209618,		 0.567823588848114		// b out
+
+	);
+
 	var _camera = new THREE.OrthographicCamera( - 1, 1, 1, - 1, 0, 1 );
 
 	var _scene = new THREE.Scene();
@@ -25,7 +46,10 @@ THREE.AnaglyphEffect = function ( renderer, width, height ) {
 		uniforms: {
 
 			"mapLeft": { type: "t", value: _renderTargetL },
-			"mapRight": { type: "t", value: _renderTargetR }
+			"mapRight": { type: "t", value: _renderTargetR },
+
+			"colorMatrixLeft": { type: "m3", value: this.colorMatrixLeft },
+			"colorMatrixRight": { type: "m3", value: this.colorMatrixRight }
 
 		},
 
@@ -48,17 +72,40 @@ THREE.AnaglyphEffect = function ( renderer, width, height ) {
 			"uniform sampler2D mapRight;",
 			"varying vec2 vUv;",
 
+			"uniform mat3 colorMatrixLeft;",
+			"uniform mat3 colorMatrixRight;",
+
+			// These functions implement sRGB linearization and gamma correction
+
+			"float lin( float c ) {",
+			"	return c <= 0.04045 ? c * 0.0773993808 :",
+			"			pow( c * 0.9478672986 + 0.0521327014, 2.4 );",
+			"}",
+
+			"vec4 lin( vec4 c ) {",
+			"	return vec4( lin( c.r ), lin( c.g ), lin( c.b ), c.a );",
+			"}",
+
+			"float dev( float c ) {",
+			"	return c <= 0.0031308 ? c * 12.92",
+			"			: pow( c, 0.41666 ) * 1.055 - 0.055;",
+			"}",
+
+
 			"void main() {",
 
-			"	vec4 colorL, colorR;",
 			"	vec2 uv = vUv;",
 
-			"	colorL = texture2D( mapLeft, uv );",
-			"	colorR = texture2D( mapRight, uv );",
+			"	vec4 colorL = lin( texture2D( mapLeft, uv ) );",
+			"	vec4 colorR = lin( texture2D( mapRight, uv ) );",
 
-				// http://3dtv.at/Knowhow/AnaglyphComparison_en.aspx
+			"	vec3 color = clamp(",
+			"			colorMatrixLeft * colorL.rgb +",
+			"			colorMatrixRight * colorR.rgb, 0., 1. );",
 
-			"	gl_FragColor = vec4( colorL.g * 0.7 + colorL.b * 0.3, colorR.g, colorR.b, colorL.a + colorR.a ) * 1.1;",
+			"	gl_FragColor = vec4(",
+			"			dev( color.r ), dev( color.g ), dev( color.b ),",
+			"			max( colorL.a, colorR.a ) );",
 
 			"}"