Trying to make less weird specular term for hemisphere light.

This is all just guessing. Other people have only diffuse term for hemisphere lights, but there should be also some specular term, in real world shiny things are shiny no matter which light.

src/renderers/WebGLShaders.js

@@ -1105,15 +1105,15 @@ THREE.ShaderChunk = {
 				"float dotProduct = dot( normal, lVector );",
 				"float hemiDiffuseWeight = 0.5 * dotProduct + 0.5;",
 
-				"hemiDiffuse += diffuse * mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight );",
+				"vec3 hemiColor = mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight );",
 
-				// specular (sky light)
+				"hemiDiffuse += diffuse * hemiColor;",
 
-				"float hemiSpecularWeight = 0.0;",
+				// specular (sky light)
 
 				"vec3 hemiHalfVectorSky = normalize( lVector + viewPosition );",
 				"float hemiDotNormalHalfSky = 0.5 * dot( normal, hemiHalfVectorSky ) + 0.5;",
-				"hemiSpecularWeight += specularStrength * max( pow( hemiDotNormalHalfSky, shininess ), 0.0 );",
+				"float hemiSpecularWeightSky = specularStrength * max( pow( hemiDotNormalHalfSky, shininess ), 0.0 );",
 
 				// specular (ground light)
 
@@ -1121,21 +1121,23 @@ THREE.ShaderChunk = {
 
 				"vec3 hemiHalfVectorGround = normalize( lVectorGround + viewPosition );",
 				"float hemiDotNormalHalfGround = 0.5 * dot( normal, hemiHalfVectorGround ) + 0.5;",
-				"hemiSpecularWeight += specularStrength * max( pow( hemiDotNormalHalfGround, shininess ), 0.0 );",
+				"float hemiSpecularWeightGround = specularStrength * max( pow( hemiDotNormalHalfGround, shininess ), 0.0 );",
 
 				"#ifdef PHYSICALLY_BASED_SHADING",
 
+					"float dotProductGround = dot( normal, lVectorGround );",
+
 					// 2.0 => 2.0001 is hack to work around ANGLE bug
 
 					"float specularNormalization = ( shininess + 2.0001 ) / 8.0;",
 
 					"vec3 schlickSky = specular + vec3( 1.0 - specular ) * pow( 1.0 - dot( lVector, hemiHalfVectorSky ), 5.0 );",
 					"vec3 schlickGround = specular + vec3( 1.0 - specular ) * pow( 1.0 - dot( lVectorGround, hemiHalfVectorGround ), 5.0 );",
-					"hemiSpecular += ( schlickSky + schlickGround ) * mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight ) * hemiSpecularWeight * hemiDiffuseWeight * specularNormalization;",
+					"hemiSpecular += hemiColor * specularNormalization * ( schlickSky * hemiSpecularWeightSky * max( dotProduct, 0.0 ) + schlickGround * hemiSpecularWeightGround * max( dotProductGround, 0.0 ) );",
 
 				"#else",
 
-					"hemiSpecular += specular * mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight ) * hemiSpecularWeight * hemiDiffuseWeight;",
+					"hemiSpecular += specular * hemiColor * ( hemiSpecularWeightSky + hemiSpecularWeightGround ) * hemiDiffuseWeight;",
 
 				"#endif",