More compatible lens flare shader code as suggested by @ajstubbs in #3603.

examples/js/shaders/FXAAShader.js

@@ -72,13 +72,14 @@ THREE.FXAAShader = {
 				  "max( vec2(-FXAA_SPAN_MAX, -FXAA_SPAN_MAX),",
 						"dir * rcpDirMin)) * resolution;",
 
-			"vec3 rgbA = 0.5 * (",
-				"texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * ( 1.0 / 3.0 - 0.5 ) ).xyz +",
-				"texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * ( 2.0 / 3.0 - 0.5 ) ).xyz );",
-
-			"vec3 rgbB = rgbA * 0.5 + 0.25 * (",
-				"texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * -0.5 ).xyz +",
-				"texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * 0.5 ).xyz );",
+			"vec3 rgbA = texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * ( 1.0 / 3.0 - 0.5 ) ).xyz;",
+			"rgbA += texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * ( 2.0 / 3.0 - 0.5 ) ).xyz;",
+			"rgbA *= 0.5;",
+
+			"vec3 rgbB = texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * -0.5 ).xyz;",
+			"rgbB += texture2D( tDiffuse, gl_FragCoord.xy  * resolution + dir * 0.5 ).xyz;",
+			"rgbB *= 0.25;",
+			"rgbB += rgbA * 0.5;",
 
 			"float lumaB = dot( rgbB, luma );",
 

src/extras/shaders/ShaderFlares.js

@@ -1,6 +1,5 @@
 /**
  * @author mikael emtinger / http://gomo.se/
- *
  */
 
 THREE.ShaderFlares = {
@@ -31,20 +30,20 @@ THREE.ShaderFlares = {
 
 				"if( renderType == 2 ) {",
 
-					"vec4 visibility = texture2D( occlusionMap, vec2( 0.1, 0.1 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.5, 0.1 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.9, 0.1 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.9, 0.5 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.9, 0.9 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.5, 0.9 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.1, 0.9 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.1, 0.5 ) ) +",
-									  "texture2D( occlusionMap, vec2( 0.5, 0.5 ) );",
-
-					"vVisibility = (       visibility.r / 9.0 ) *",
-								  "( 1.0 - visibility.g / 9.0 ) *",
-								  "(       visibility.b / 9.0 ) *",
-								  "( 1.0 - visibility.a / 9.0 );",
+					"vec4 visibility = texture2D( occlusionMap, vec2( 0.1, 0.1 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.5, 0.1 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.9, 0.1 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.9, 0.5 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.9, 0.9 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.5, 0.9 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.1, 0.9 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.1, 0.5 ) );",
+					"visibility += texture2D( occlusionMap, vec2( 0.5, 0.5 ) );",
+
+					"vVisibility =        visibility.r / 9.0;",
+					"vVisibility *= 1.0 - visibility.g / 9.0;",
+					"vVisibility *=       visibility.b / 9.0;",
+					"vVisibility *= 1.0 - visibility.a / 9.0;",
 
 					"pos.x = cos( rotation ) * position.x - sin( rotation ) * position.y;",
 					"pos.y = sin( rotation ) * position.x + cos( rotation ) * position.y;",
@@ -164,11 +163,10 @@ THREE.ShaderFlares = {
 
 				"} else {",
 
-					"float visibility = texture2D( occlusionMap, vec2( 0.5, 0.1 ) ).a +",
-									   "texture2D( occlusionMap, vec2( 0.9, 0.5 ) ).a +",
-									   "texture2D( occlusionMap, vec2( 0.5, 0.9 ) ).a +",
-									   "texture2D( occlusionMap, vec2( 0.1, 0.5 ) ).a;",
-
+					"float visibility = texture2D( occlusionMap, vec2( 0.5, 0.1 ) ).a;",
+					"visibility += texture2D( occlusionMap, vec2( 0.9, 0.5 ) ).a;",
+					"visibility += texture2D( occlusionMap, vec2( 0.5, 0.9 ) ).a;",
+					"visibility += texture2D( occlusionMap, vec2( 0.1, 0.5 ) ).a;",
 					"visibility = ( 1.0 - visibility / 4.0 );",
 
 					"vec4 texture = texture2D( map, vUV );",