Added normal_flip.glsl

src/renderers/shaders/ShaderChunk/envmap_fragment.glsl

@@ -23,11 +23,7 @@
 
 	#endif
 
-	#ifdef DOUBLE_SIDED
-		float flipNormal = ( float( gl_FrontFacing ) * 2.0 - 1.0 );
-	#else
-		float flipNormal = 1.0;
-	#endif
+	#include <normal_flip>
 
 	#ifdef ENVMAP_TYPE_CUBE
 
@@ -42,7 +38,7 @@
 
 	#elif defined( ENVMAP_TYPE_SPHERE )
 
-		vec3 reflectView = flipNormal * normalize((viewMatrix * vec4( reflectVec, 0.0 )).xyz + vec3(0.0,0.0,1.0));
+		vec3 reflectView = flipNormal * normalize( ( viewMatrix * vec4( reflectVec, 0.0 ) ).xyz + vec3( 0.0, 0.0, 1.0 ) );
 		vec4 envColor = texture2D( envMap, reflectView.xy * 0.5 + 0.5 );
 
 	#endif

src/renderers/shaders/ShaderChunk/lights_pars.glsl

@@ -165,15 +165,7 @@ vec3 getAmbientLightIrradiance( const in vec3 ambientLightColor ) {
 
 	vec3 getLightProbeIndirectIrradiance( /*const in SpecularLightProbe specularLightProbe,*/ const in GeometricContext geometry, const in int maxMIPLevel ) {
 
-		#ifdef DOUBLE_SIDED
-
-			float flipNormal = ( float( gl_FrontFacing ) * 2.0 - 1.0 );
-
-		#else
-
-			float flipNormal = 1.0;
-
-		#endif
+		#include <normal_flip>
 
 		vec3 worldNormal = inverseTransformDirection( geometry.normal, viewMatrix );
 
@@ -238,15 +230,7 @@ vec3 getAmbientLightIrradiance( const in vec3 ambientLightColor ) {
 
 		#endif
 
-		#ifdef DOUBLE_SIDED
-
-			float flipNormal = ( float( gl_FrontFacing ) * 2.0 - 1.0 );
-
-		#else
-
-			float flipNormal = 1.0;
-
-		#endif
+		#include <normal_flip>
 
 		reflectVec = inverseTransformDirection( reflectVec, viewMatrix );
 
@@ -293,7 +277,7 @@ vec3 getAmbientLightIrradiance( const in vec3 ambientLightColor ) {
 
 		#elif defined( ENVMAP_TYPE_SPHERE )
 
-			vec3 reflectView = flipNormal * normalize((viewMatrix * vec4( reflectVec, 0.0 )).xyz + vec3(0.0,0.0,1.0));
+			vec3 reflectView = flipNormal * normalize( ( viewMatrix * vec4( reflectVec, 0.0 ) ).xyz + vec3( 0.0,0.0,1.0 ) );
 
 			#ifdef TEXTURE_LOD_EXT
 

src/renderers/shaders/ShaderChunk/normal_flip.glsl

@@ -0,0 +1,5 @@
+#ifdef DOUBLE_SIDED
+	float flipNormal = ( float( gl_FrontFacing ) * 2.0 - 1.0 );
+#else
+	float flipNormal = 1.0;
+#endif

src/renderers/shaders/ShaderChunk/normal_fragment.glsl

@@ -8,13 +8,9 @@
 
 #else
 
-	vec3 normal = normalize( vNormal );
+#include <normal_flip>
 
-	#ifdef DOUBLE_SIDED
-
-		normal = normal * ( -1.0 + 2.0 * float( gl_FrontFacing ) );
-
-	#endif
+	vec3 normal = normalize( vNormal ) * flipNormal;
 
 #endif
 

utils/build/includes/common.json

@@ -180,6 +180,7 @@
 	"src/renderers/shaders/ShaderChunk/morphnormal_vertex.glsl",
 	"src/renderers/shaders/ShaderChunk/morphtarget_pars_vertex.glsl",
 	"src/renderers/shaders/ShaderChunk/morphtarget_vertex.glsl",
+	"src/renderers/shaders/ShaderChunk/normal_flip.glsl",
 	"src/renderers/shaders/ShaderChunk/normal_fragment.glsl",
 	"src/renderers/shaders/ShaderChunk/normalmap_pars_fragment.glsl",
 	"src/renderers/shaders/ShaderChunk/packing.glsl",