Merge pull request #6224 from WestLangley/dev-lambert

Lambert: calculate incoming light in vertex shader; outgoing light in...

src/renderers/shaders/ShaderChunk/lights_lambert_pars_vertex.glsl

-uniform vec3 diffuse;
-uniform vec3 emissive;
-
 uniform vec3 ambientLightColor;
 
 #if MAX_DIR_LIGHTS > 0

src/renderers/shaders/ShaderChunk/lights_lambert_vertex.glsl

@@ -187,10 +187,10 @@ for( int i = 0; i < MAX_DIR_LIGHTS; i ++ ) {
 
 #endif
 
-vLightFront = vLightFront * diffuse + diffuse * ambientLightColor + emissive;
+vLightFront += ambientLightColor;
 
 #ifdef DOUBLE_SIDED
 
-	vLightBack = vLightBack * diffuse + diffuse * ambientLightColor + emissive;
+	vLightBack += ambientLightColor;
 
 #endif

src/renderers/shaders/ShaderLib.js

@@ -171,8 +171,11 @@ THREE.ShaderLib = {
 
 		fragmentShader: [
 
+			"uniform vec3 diffuse;",
 			"uniform float opacity;",
 
+			"uniform vec3 emissive;",
+
 			"varying vec3 vLightFront;",
 
 			"#ifdef DOUBLE_SIDED",
@@ -195,7 +198,7 @@ THREE.ShaderLib = {
 			"void main() {",
 
 			"	vec3 outgoingLight = vec3( 0.0 );",	// outgoing light does not have an alpha, the surface does
-			"	vec4 diffuseColor = vec4( 1.0, 1.0, 1.0, opacity );",
+			"	vec4 diffuseColor = vec4( diffuse, opacity );",
 
 				THREE.ShaderChunk[ "logdepthbuf_fragment" ],
 				THREE.ShaderChunk[ "map_fragment" ],
@@ -210,13 +213,13 @@ THREE.ShaderLib = {
 					//"gl_FragColor.xyz *= isFront * vLightFront + ( 1.0 - isFront ) * vLightBack;",
 
 			"		if ( gl_FrontFacing )",
-			"			outgoingLight += diffuseColor.rgb * vLightFront;",
+			"			outgoingLight += diffuseColor.rgb * vLightFront + emissive;",
 			"		else",
-			"			outgoingLight += diffuseColor.rgb * vLightBack;",
+			"			outgoingLight += diffuseColor.rgb * vLightBack + emissive;",
 
 			"	#else",
 
-			"		outgoingLight += diffuseColor.rgb * vLightFront;",
+			"		outgoingLight += diffuseColor.rgb * vLightFront + emissive;",
 
 			"	#endif",