Improve lighting of entities.

Pass correct natural & artificial light to the shaders
Use natural/artificial light ratio for correct rendering of shadows

client/shaders/object_shader/opengl_fragment.glsl

@@ -471,7 +471,7 @@ void main(void)
 	color = base.rgb;
 	vec4 col = vec4(color.rgb, base.a);
 	col.rgb *= varColor.rgb;
-	col.rgb *= emissiveColor.rgb * vIDiff;
+	col.rgb *= vIDiff;
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
 	float shadow_int = 0.0;

client/shaders/object_shader/opengl_vertex.glsl

@@ -1,7 +1,9 @@
 uniform mat4 mWorld;
-
+uniform vec3 dayLight;
 uniform vec3 eyePosition;
 uniform float animationTimer;
+uniform vec4 emissiveColor;
+
 
 varying vec3 vNormal;
 varying vec3 vPosition;
@@ -29,9 +31,9 @@ centroid varying vec2 varTexCoord;
 
 varying vec3 eyeVec;
 varying float nightRatio;
-
+// Color of the light emitted by the light sources.
+const vec3 artificialLight = vec3(1.04, 1.04, 1.04);
 varying float vIDiff;
-
 const float e = 2.718281828459;
 const float BS = 10.0;
 
@@ -75,14 +77,30 @@ void main(void)
 		? 1.0
 		: directional_ambient(normalize(inVertexNormal));
 #endif
-	nightRatio = 0.0;
 
 #ifdef GL_ES
-	varColor = inVertexColor.bgra;
+	vec4 color = inVertexColor.bgra;
 #else
-	varColor = inVertexColor;
+	vec4 color = inVertexColor;
 #endif
 
+	color *= emissiveColor;
+
+	// The alpha gives the ratio of sunlight in the incoming light.
+	nightRatio = 1.0 - color.a;
+	color.rgb = color.rgb * (color.a * dayLight.rgb +
+		nightRatio * artificialLight.rgb) * 2.0;
+	color.a = 1.0;
+
+	// Emphase blue a bit in darker places
+	// See C++ implementation in mapblock_mesh.cpp final_color_blend()
+	float brightness = (color.r + color.g + color.b) / 3.0;
+	color.b += max(0.0, 0.021 - abs(0.2 * brightness - 0.021) +
+		0.07 * brightness);
+
+	varColor = clamp(color, 0.0, 1.0);
+
+
 #ifdef ENABLE_DYNAMIC_SHADOWS
 	vec3 nNormal = normalize(vNormal);
 	cosLight = dot(nNormal, -v_LightDirection);

src/client/content_cao.cpp

@@ -864,7 +864,8 @@ void GenericCAO::updateLight(u32 day_night_ratio)
 	if (m_glow < 0)
 		return;
 
-	u8 light_at_pos = 0;
+	u16 light_at_pos = 0;
+	u8 light_at_pos_intensity = 0;
 	bool pos_ok = false;
 
 	v3s16 pos[3];
@@ -873,28 +874,33 @@ void GenericCAO::updateLight(u32 day_night_ratio)
 		bool this_ok;
 		MapNode n = m_env->getMap().getNode(pos[i], &this_ok);
 		if (this_ok) {
-			u8 this_light = n.getLightBlend(day_night_ratio, m_client->ndef());
-			light_at_pos = MYMAX(light_at_pos, this_light);
+			u16 this_light = getInteriorLight(n, 0, m_client->ndef());
+			u8 this_light_intensity = MYMAX(this_light & 0xFF, (this_light >> 8) && 0xFF);
+			if (this_light_intensity > light_at_pos_intensity) {
+				light_at_pos = this_light;
+				light_at_pos_intensity = this_light_intensity;
+			}
 			pos_ok = true;
 		}
 	}
 	if (!pos_ok)
-		light_at_pos = blend_light(day_night_ratio, LIGHT_SUN, 0);
+		light_at_pos = LIGHT_SUN;
+
+	video::SColor light = encode_light(light_at_pos, m_glow);
+	if (!m_enable_shaders)
+		final_color_blend(&light, light_at_pos, day_night_ratio);
 
-	u8 light = decode_light(light_at_pos + m_glow);
 	if (light != m_last_light) {
 		m_last_light = light;
 		setNodeLight(light);
 	}
 }
 
-void GenericCAO::setNodeLight(u8 light)
+void GenericCAO::setNodeLight(const video::SColor &light_color)
 {
-	video::SColor color(255, light, light, light);
-
 	if (m_prop.visual == "wielditem" || m_prop.visual == "item") {
 		if (m_wield_meshnode)
-			m_wield_meshnode->setNodeLightColor(color);
+			m_wield_meshnode->setNodeLightColor(light_color);
 		return;
 	}
 
@@ -906,7 +912,7 @@ void GenericCAO::setNodeLight(u8 light)
 			scene::IMesh *mesh = m_meshnode->getMesh();
 			for (u32 i = 0; i < mesh->getMeshBufferCount(); ++i) {
 				scene::IMeshBuffer *buf = mesh->getMeshBuffer(i);
-				buf->getMaterial().EmissiveColor = color;
+				buf->getMaterial().EmissiveColor = light_color;
 			}
 		} else {
 			scene::ISceneNode *node = getSceneNode();
@@ -915,16 +921,16 @@ void GenericCAO::setNodeLight(u8 light)
 
 			for (u32 i = 0; i < node->getMaterialCount(); ++i) {
 				video::SMaterial &material = node->getMaterial(i);
-				material.EmissiveColor = color;
+				material.EmissiveColor = light_color;
 			}
 		}
 	} else {
 		if (m_meshnode) {
-			setMeshColor(m_meshnode->getMesh(), color);
+			setMeshColor(m_meshnode->getMesh(), light_color);
 		} else if (m_animated_meshnode) {
-			setAnimatedMeshColor(m_animated_meshnode, color);
+			setAnimatedMeshColor(m_animated_meshnode, light_color);
 		} else if (m_spritenode) {
-			m_spritenode->setColor(color);
+			m_spritenode->setColor(light_color);
 		}
 	}
 }

src/client/content_cao.h

@@ -125,7 +125,7 @@ private:
 	std::string m_current_texture_modifier = "";
 	bool m_visuals_expired = false;
 	float m_step_distance_counter = 0.0f;
-	u8 m_last_light = 255;
+	video::SColor m_last_light = video::SColor(0xFFFFFFFF);
 	bool m_is_visible = false;
 	s8 m_glow = 0;
 	// Material
@@ -245,7 +245,7 @@ public:
 
 	void updateLight(u32 day_night_ratio);
 
-	void setNodeLight(u8 light);
+	void setNodeLight(const video::SColor &light);
 
 	/* Get light position(s).
 	 * returns number of positions written into pos[], which must have space

src/client/wieldmesh.cpp

@@ -515,9 +515,10 @@ void WieldMeshSceneNode::setNodeLightColor(video::SColor color)
 			material.EmissiveColor = color;
 		}
 	}
-
+	else {
 		setColor(color);
 	}
+}
 
 void WieldMeshSceneNode::render()
 {