-Ability to choose operator for emission, closes #10441

-Ability to use proper operator for GI Probe, closes #10534
-Closes #12938 as it's no longer needed (thanks for the work though)

scene/3d/gi_probe.cpp

@@ -891,7 +891,7 @@ void GIProbe::_fixup_plot(int p_idx, int p_level, int p_x, int p_y, int p_z, Bak
 	}
 }
 
-Vector<Color> GIProbe::_get_bake_texture(Ref<Image> p_image, const Color &p_color) {
+Vector<Color> GIProbe::_get_bake_texture(Ref<Image> p_image, const Color &p_color, bool p_color_add) {
 
 	Vector<Color> ret;
 
@@ -919,9 +919,16 @@ Vector<Color> GIProbe::_get_bake_texture(Ref<Image> p_image, const Color &p_colo
 
 	for (int i = 0; i < bake_texture_size * bake_texture_size; i++) {
 		Color c;
-		c.r = (r[i * 4 + 0] / 255.0) * p_color.r;
+		if (p_color_add) {
-		c.g = (r[i * 4 + 1] / 255.0) * p_color.g;
+			c.r = (r[i * 4 + 0] / 255.0) + p_color.r;
-		c.b = (r[i * 4 + 2] / 255.0) * p_color.b;
+			c.g = (r[i * 4 + 1] / 255.0) + p_color.g;
+			c.b = (r[i * 4 + 2] / 255.0) + p_color.b;
+		} else {
+			c.r = (r[i * 4 + 0] / 255.0) * p_color.r;
+			c.g = (r[i * 4 + 1] / 255.0) * p_color.g;
+			c.b = (r[i * 4 + 2] / 255.0) * p_color.b;
+		}
+
 		c.a = r[i * 4 + 3] / 255.0;
 
 		ret[i] = c;
@@ -954,7 +961,7 @@ GIProbe::Baker::MaterialCache GIProbe::_get_material_cache(Ref<Material> p_mater
 		} else {
 		}
 
-		mc.albedo = _get_bake_texture(img_albedo, mat->get_albedo());
+		mc.albedo = _get_bake_texture(img_albedo, mat->get_albedo(), false);
 
 		Ref<ImageTexture> emission_tex = mat->get_texture(SpatialMaterial::TEXTURE_EMISSION);
 
@@ -970,7 +977,7 @@ GIProbe::Baker::MaterialCache GIProbe::_get_material_cache(Ref<Material> p_mater
 			img_emission = emission_tex->get_data();
 		}
 
-		mc.emission = _get_bake_texture(img_emission, emission_col);
+		mc.emission = _get_bake_texture(img_emission, emission_col, mat->get_emission_operator() == SpatialMaterial::EMISSION_OP_ADD);
 
 	} else {
 		Ref<Image> empty;

scene/3d/gi_probe.h

@@ -178,7 +178,7 @@ private:
 	int color_scan_cell_width;
 	int bake_texture_size;
 
-	Vector<Color> _get_bake_texture(Ref<Image> p_image, const Color &p_color);
+	Vector<Color> _get_bake_texture(Ref<Image> p_image, const Color &p_color, bool p_color_add = false);
 	Baker::MaterialCache _get_material_cache(Ref<Material> p_material, Baker *p_baker);
 	void _plot_face(int p_idx, int p_level, int p_x, int p_y, int p_z, const Vector3 *p_vtx, const Vector2 *p_uv, const Baker::MaterialCache &p_material, const Rect3 &p_aabb, Baker *p_baker);
 	void _plot_mesh(const Transform &p_xform, Ref<Mesh> &p_mesh, Baker *p_baker, const Vector<Ref<Material> > &p_materials, const Ref<Material> &p_override_material);

scene/resources/material.cpp

@@ -723,7 +723,11 @@ void SpatialMaterial::_update_shader() {
 		} else {
 			code += "\tvec3 emission_tex = texture(texture_emission,base_uv).rgb;\n";
 		}
-		code += "\tEMISSION = (emission.rgb+emission_tex)*emission_energy;\n";
+		if (emission_op == EMISSION_OP_ADD) {
+			code += "\tEMISSION = (emission.rgb+emission_tex)*emission_energy;\n";
+		} else {
+			code += "\tEMISSION = (emission.rgb*emission_tex)*emission_energy;\n";
+		}
 	}
 
 	if (features[FEATURE_REFRACTION] && !flags[FLAG_UV1_USE_TRIPLANAR]) { //refraction not supported with triplanar
@@ -1635,6 +1639,19 @@ float SpatialMaterial::get_distance_fade_min_distance() const {
 	return distance_fade_min_distance;
 }
 
+void SpatialMaterial::set_emission_operator(EmissionOperator p_op) {
+
+	if (emission_op == p_op)
+		return;
+	emission_op = p_op;
+	_queue_shader_change();
+}
+
+SpatialMaterial::EmissionOperator SpatialMaterial::get_emission_operator() const {
+
+	return emission_op;
+}
+
 RID SpatialMaterial::get_shader_rid() const {
 
 	ERR_FAIL_COND_V(!shader_map.has(current_key), RID());
@@ -1769,6 +1786,9 @@ void SpatialMaterial::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_grow", "amount"), &SpatialMaterial::set_grow);
 	ClassDB::bind_method(D_METHOD("get_grow"), &SpatialMaterial::get_grow);
 
+	ClassDB::bind_method(D_METHOD("set_emission_operator", "operator"), &SpatialMaterial::set_emission_operator);
+	ClassDB::bind_method(D_METHOD("get_emission_operator"), &SpatialMaterial::get_emission_operator);
+
 	ClassDB::bind_method(D_METHOD("set_ao_light_affect", "amount"), &SpatialMaterial::set_ao_light_affect);
 	ClassDB::bind_method(D_METHOD("get_ao_light_affect"), &SpatialMaterial::get_ao_light_affect);
 
@@ -1854,6 +1874,7 @@ void SpatialMaterial::_bind_methods() {
 	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "emission_enabled"), "set_feature", "get_feature", FEATURE_EMISSION);
 	ADD_PROPERTY(PropertyInfo(Variant::COLOR, "emission", PROPERTY_HINT_COLOR_NO_ALPHA), "set_emission", "get_emission");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "emission_energy", PROPERTY_HINT_RANGE, "0,16,0.01"), "set_emission_energy", "get_emission_energy");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "emission_operator", PROPERTY_HINT_ENUM, "Add,Multiply"), "set_emission_operator", "get_emission_operator");
 	ADD_PROPERTYI(PropertyInfo(Variant::OBJECT, "emission_texture", PROPERTY_HINT_RESOURCE_TYPE, "Texture"), "set_texture", "get_texture", TEXTURE_EMISSION);
 
 	ADD_GROUP("NormalMap", "normal_");
@@ -2022,6 +2043,9 @@ void SpatialMaterial::_bind_methods() {
 	BIND_ENUM_CONSTANT(TEXTURE_CHANNEL_BLUE);
 	BIND_ENUM_CONSTANT(TEXTURE_CHANNEL_ALPHA);
 	BIND_ENUM_CONSTANT(TEXTURE_CHANNEL_GRAYSCALE);
+
+	BIND_ENUM_CONSTANT(EMISSION_OP_ADD);
+	BIND_ENUM_CONSTANT(EMISSION_OP_MULTIPLY);
 }
 
 SpatialMaterial::SpatialMaterial()
@@ -2057,6 +2081,7 @@ SpatialMaterial::SpatialMaterial()
 	set_particles_anim_v_frames(1);
 	set_particles_anim_loop(false);
 	set_alpha_scissor_threshold(0.98);
+	emission_op = EMISSION_OP_ADD;
 
 	proximity_fade_enabled = false;
 	distance_fade_enabled = false;

scene/resources/material.h

@@ -215,6 +215,11 @@ public:
 		TEXTURE_CHANNEL_GRAYSCALE
 	};
 
+	enum EmissionOperator {
+		EMISSION_OP_ADD,
+		EMISSION_OP_MULTIPLY
+	};
+
 private:
 	union MaterialKey {
 
@@ -234,6 +239,7 @@ private:
 			uint64_t grow : 1;
 			uint64_t proximity_fade : 1;
 			uint64_t distance_fade : 1;
+			uint64_t emission_op : 1;
 		};
 
 		uint64_t key;
@@ -278,6 +284,7 @@ private:
 		mk.grow = grow_enabled;
 		mk.proximity_fade = proximity_fade_enabled;
 		mk.distance_fade = distance_fade_enabled;
+		mk.emission_op = emission_op;
 
 		return mk;
 	}
@@ -394,6 +401,7 @@ private:
 	SpecularMode specular_mode;
 	DiffuseMode diffuse_mode;
 	BillboardMode billboard_mode;
+	EmissionOperator emission_op;
 
 	TextureChannel metallic_texture_channel;
 	TextureChannel roughness_texture_channel;
@@ -571,6 +579,9 @@ public:
 	void set_distance_fade_min_distance(float p_distance);
 	float get_distance_fade_min_distance() const;
 
+	void set_emission_operator(EmissionOperator p_op);
+	EmissionOperator get_emission_operator() const;
+
 	void set_metallic_texture_channel(TextureChannel p_channel);
 	TextureChannel get_metallic_texture_channel() const;
 	void set_roughness_texture_channel(TextureChannel p_channel);
@@ -603,6 +614,7 @@ VARIANT_ENUM_CAST(SpatialMaterial::DiffuseMode)
 VARIANT_ENUM_CAST(SpatialMaterial::SpecularMode)
 VARIANT_ENUM_CAST(SpatialMaterial::BillboardMode)
 VARIANT_ENUM_CAST(SpatialMaterial::TextureChannel)
+VARIANT_ENUM_CAST(SpatialMaterial::EmissionOperator)
 
 //////////////////////