diff --git a/areas/world_area.cpp b/areas/world_area.cpp
index e09683c..22abcd1 100644
--- a/areas/world_area.cpp
+++ b/areas/world_area.cpp
@@ -32,21 +32,21 @@ void WorldArea::set_aabb(const AABB value) {
 Ref<Texture> WorldArea::get_map_texture() const {
 	return _map_texture;
 }
-void WorldArea::set_map_texture(const Ref<Texture> value) {
+void WorldArea::set_map_texture(const Ref<Texture> &value) {
 	_map_texture = value;
 }
 
 Ref<Texture> WorldArea::get_fov_texture() const {
 	return _fov_texture;
 }
-void WorldArea::set_fov_texture(const Ref<Texture> value) {
+void WorldArea::set_fov_texture(const Ref<Texture> &value) {
 	_fov_texture = value;
 }
 
 String WorldArea::get_name() const {
 	return _name;
 }
-void WorldArea::set_name(const String value) {
+void WorldArea::set_name(const String &value) {
 	_name = value;
 }
 
diff --git a/areas/world_area.h b/areas/world_area.h
index 940c8d2..6105412 100644
--- a/areas/world_area.h
+++ b/areas/world_area.h
@@ -37,13 +37,13 @@ public:
 	void set_aabb(const AABB value);
 
 	Ref<Texture> get_map_texture() const;
-	void set_map_texture(const Ref<Texture> value);
+	void set_map_texture(const Ref<Texture> &value);
 
 	Ref<Texture> get_fov_texture() const;
-	void set_fov_texture(const Ref<Texture> value);
+	void set_fov_texture(const Ref<Texture> &value);
 
 	String get_name() const;
-	void set_name(const String value);
+	void set_name(const String &value);
 
 	int get_level() const;
 	void set_level(const int value);
diff --git a/data/voxel_light.cpp b/data/voxel_light.cpp
index 371d895..e0df386 100644
--- a/data/voxel_light.cpp
+++ b/data/voxel_light.cpp
@@ -43,7 +43,7 @@ void VoxelLight::set_world_position(const int x, const int y, const int z) {
 _FORCE_INLINE_ Color VoxelLight::get_color() const {
 	return _color;
 }
-void VoxelLight::set_color(Color color) {
+void VoxelLight::set_color(const Color &color) {
 	_color = color;
 }
 
diff --git a/data/voxel_light.h b/data/voxel_light.h
index b794aa9..4374ae8 100644
--- a/data/voxel_light.h
+++ b/data/voxel_light.h
@@ -38,7 +38,7 @@ public:
 	void set_world_position(const int x, const int y, const int z);
 
 	Color get_color() const;
-	void set_color(const Color color);
+	void set_color(const Color &color);
 
 	float get_size() const;
 	void set_size(const float strength);
diff --git a/library/voxel_surface.cpp b/library/voxel_surface.cpp
index 380e1e8..488e68d 100644
--- a/library/voxel_surface.cpp
+++ b/library/voxel_surface.cpp
@@ -46,7 +46,7 @@ void VoxelSurface::set_transparent(const bool transparent) {
 Rect2 VoxelSurface::get_rect(const VoxelSurfaceSides side) const {
 	return _rects[side];
 }
-void VoxelSurface::set_rect(const VoxelSurfaceSides side, const Rect2 rect) {
+void VoxelSurface::set_rect(const VoxelSurfaceSides side, const Rect2 &rect) {
 	_rects[side] = rect;
 }
 
@@ -58,7 +58,7 @@ void VoxelSurface::set_library(Ref<VoxelmanLibrary> library) {
 	_library = (*library);
 }
 
-_FORCE_INLINE_ Vector2 VoxelSurface::transform_uv(const VoxelSurfaceSides p_side, const Vector2 p_uv) const {
+_FORCE_INLINE_ Vector2 VoxelSurface::transform_uv(const VoxelSurfaceSides p_side, const Vector2 &p_uv) const {
 	Vector2 uv = p_uv;
 
 	Rect2 r = _rects[p_side];
@@ -71,7 +71,7 @@ _FORCE_INLINE_ Vector2 VoxelSurface::transform_uv(const VoxelSurfaceSides p_side
 	return uv;
 }
 
-_FORCE_INLINE_ Vector2 VoxelSurface::transform_uv_scaled(const VoxelSurfaceSides p_side, const Vector2 p_uv, int p_current_x, int p_current_y, int p_max) const {
+_FORCE_INLINE_ Vector2 VoxelSurface::transform_uv_scaled(const VoxelSurfaceSides p_side, const Vector2 &p_uv, const int p_current_x, const int p_current_y, const int p_max) const {
 	Vector2 uv = p_uv;
 
 	Rect2 r = _rects[p_side];
diff --git a/library/voxel_surface.h b/library/voxel_surface.h
index fad4629..e2382ea 100644
--- a/library/voxel_surface.h
+++ b/library/voxel_surface.h
@@ -74,13 +74,13 @@ public:
 	void set_transparent(const bool transparent);
 
 	Rect2 get_rect(const VoxelSurfaceSides side) const;
-	void set_rect(const VoxelSurfaceSides side, const Rect2 rect);
+	void set_rect(const VoxelSurfaceSides side, const Rect2 &rect);
 
 	Ref<VoxelmanLibrary> get_library() const;
 	void set_library(Ref<VoxelmanLibrary> library);
 
-	Vector2 transform_uv(const VoxelSurfaceSides p_side, const Vector2 p_uv) const;
-	Vector2 transform_uv_scaled(const VoxelSurfaceSides p_side, const Vector2 p_uv, int p_current_x, int p_current_y, int p_max) const;
+	Vector2 transform_uv(const VoxelSurfaceSides p_side, const Vector2 &p_uv) const;
+	Vector2 transform_uv_scaled(const VoxelSurfaceSides p_side, const Vector2 &p_uv, const int p_current_x, const int p_current_y, const int p_max) const;
 
 	virtual void refresh_rects();
 
diff --git a/library/voxel_surface_merger.cpp b/library/voxel_surface_merger.cpp
index f49848b..81e621d 100644
--- a/library/voxel_surface_merger.cpp
+++ b/library/voxel_surface_merger.cpp
@@ -35,14 +35,14 @@ typedef class StandardMaterial3D SpatialMaterial;
 Ref<AtlasTexture> VoxelSurfaceMerger::get_region(const VoxelSurfaceSides side) {
 	return _regions[side];
 }
-void VoxelSurfaceMerger::set_region(const VoxelSurfaceSides side, Ref<AtlasTexture> texture) {
+void VoxelSurfaceMerger::set_region(const VoxelSurfaceSides side, const Ref<AtlasTexture> &texture) {
 	_regions[side] = texture;
 }
 
 Ref<Texture> VoxelSurfaceMerger::get_texture(const VoxelSurfaceSides side) {
 	return _textures[side];
 }
-void VoxelSurfaceMerger::set_texture(const VoxelSurfaceSides side, Ref<Texture> texture) {
+void VoxelSurfaceMerger::set_texture(const VoxelSurfaceSides side, const Ref<Texture> &texture) {
 	_textures[side] = texture;
 }
 
diff --git a/library/voxel_surface_merger.h b/library/voxel_surface_merger.h
index 916f480..61b6eec 100644
--- a/library/voxel_surface_merger.h
+++ b/library/voxel_surface_merger.h
@@ -40,10 +40,10 @@ class VoxelSurfaceMerger : public VoxelSurface {
 
 public:
 	Ref<AtlasTexture> get_region(const VoxelSurfaceSides side);
-	void set_region(const VoxelSurfaceSides side, Ref<AtlasTexture> texture);
+	void set_region(const VoxelSurfaceSides side, const Ref<AtlasTexture> &texture);
 
 	Ref<Texture> get_texture(const VoxelSurfaceSides side);
-	void set_texture(const VoxelSurfaceSides side, Ref<Texture> texture);
+	void set_texture(const VoxelSurfaceSides side, const Ref<Texture> &texture);
 
 	void refresh_rects();
 
diff --git a/library/voxelman_library_merger.cpp b/library/voxelman_library_merger.cpp
index 9cd3c7d..5b9ab18 100644
--- a/library/voxelman_library_merger.cpp
+++ b/library/voxelman_library_merger.cpp
@@ -55,7 +55,7 @@ void VoxelmanLibraryMerger::set_keep_original_atlases(const bool value) {
 Color VoxelmanLibraryMerger::get_background_color() const {
 	return _packer->get_background_color();
 }
-void VoxelmanLibraryMerger::set_background_color(const Color color) {
+void VoxelmanLibraryMerger::set_background_color(const Color &color) {
 	_packer->set_background_color(color);
 }
 
@@ -252,7 +252,7 @@ void VoxelmanLibraryMerger::add_prop(Ref<PackedScene> value) {
 
 	////_props[value->get_id()] = value;
 }
-void VoxelmanLibraryMerger::set_prop(const int id, Ref<PackedScene> value) {
+void VoxelmanLibraryMerger::set_prop(const int id, const Ref<PackedScene> &value) {
 	//_props[value->get_id()] = value;
 }
 void VoxelmanLibraryMerger::remove_prop(const int id) {
@@ -335,7 +335,7 @@ void VoxelmanLibraryMerger::refresh_rects() {
 	}
 }
 
-void VoxelmanLibraryMerger::_setup_material_albedo(int material_index, Ref<Texture> texture) {
+void VoxelmanLibraryMerger::_setup_material_albedo(const int material_index, const Ref<Texture> &texture) {
 	Ref<SpatialMaterial> mat;
 
 	int count = 0;
diff --git a/library/voxelman_library_merger.h b/library/voxelman_library_merger.h
index a0b55b5..7c744eb 100644
--- a/library/voxelman_library_merger.h
+++ b/library/voxelman_library_merger.h
@@ -50,7 +50,7 @@ public:
 	void set_keep_original_atlases(const bool value);
 
 	Color get_background_color() const;
-	void set_background_color(const Color color);
+	void set_background_color(const Color &color);
 
 	int get_margin() const;
 	void set_margin(const int margin);
@@ -77,7 +77,7 @@ public:
 
 	Ref<PackedScene> get_prop(const int id);
 	void add_prop(Ref<PackedScene> value);
-	void set_prop(const int id, Ref<PackedScene> value);
+	void set_prop(const int id, const Ref<PackedScene> &value);
 	void remove_prop(const int id);
 	int get_num_props() const;
 	void clear_props();
@@ -87,7 +87,7 @@ public:
 
 	void refresh_rects();
 
-	void _setup_material_albedo(int material_index, Ref<Texture> texture);
+	void _setup_material_albedo(const int material_index, const Ref<Texture> &texture);
 
 	VoxelmanLibraryMerger();
 	~VoxelmanLibraryMerger();
diff --git a/world/environment_data.cpp b/world/environment_data.cpp
index d4b0ca8..2660862 100644
--- a/world/environment_data.cpp
+++ b/world/environment_data.cpp
@@ -31,36 +31,36 @@ SOFTWARE.
 Ref<Environment> EnvironmentData::get_environment() {
 	return _environment;
 }
-void EnvironmentData::set_environment(Ref<Environment> value) {
+void EnvironmentData::set_environment(const Ref<Environment> &value) {
 	_environment = value;
 }
 
-Color EnvironmentData::get_color(int index) {
+Color EnvironmentData::get_color(const int index) {
 	ERR_FAIL_INDEX_V(index, LIGHT_COUNT, Color());
 
 	return _colors[index];
 }
-void EnvironmentData::set_color(int index, Color value) {
+void EnvironmentData::set_color(const int index, const Color &value) {
 	ERR_FAIL_INDEX(index, LIGHT_COUNT);
 
 	_colors[index] = value;
 }
-float EnvironmentData::get_energy(int index) {
+float EnvironmentData::get_energy(const int index) {
 	ERR_FAIL_INDEX_V(index, LIGHT_COUNT, 0);
 
 	return _energies[index];
 }
-void EnvironmentData::set_energy(int index, float value) {
+void EnvironmentData::set_energy(const int index, const float value) {
 	ERR_FAIL_INDEX(index, LIGHT_COUNT);
 
 	_energies[index] = value;
 }
-float EnvironmentData::get_indirect_energy(int index) {
+float EnvironmentData::get_indirect_energy(const int index) {
 	ERR_FAIL_INDEX_V(index, LIGHT_COUNT, 0);
 
 	return _indirect_energies[index];
 }
-void EnvironmentData::set_indirect_energy(int index, float value) {
+void EnvironmentData::set_indirect_energy(const int index, const float value) {
 	ERR_FAIL_INDEX(index, LIGHT_COUNT);
 
 	_indirect_energies[index] = value;
diff --git a/world/environment_data.h b/world/environment_data.h
index 369171b..b8b0fed 100644
--- a/world/environment_data.h
+++ b/world/environment_data.h
@@ -44,14 +44,14 @@ class EnvironmentData : public Resource {
 
 public:
 	Ref<Environment> get_environment();
-	void set_environment(Ref<Environment> value);
+	void set_environment(const Ref<Environment> &value);
 
-	Color get_color(int index);
-	void set_color(int index, Color value);
-	float get_energy(int index);
-	void set_energy(int index, float value);
-	float get_indirect_energy(int index);
-	void set_indirect_energy(int index, float value);
+	Color get_color(const int index);
+	void set_color(const int index, const Color &value);
+	float get_energy(const int index);
+	void set_energy(const int index, const float value);
+	float get_indirect_energy(const int index);
+	void set_indirect_energy(const int index, const float value);
 
 	void setup(WorldEnvironment *world_environment, DirectionalLight *primary_light, DirectionalLight *secondary_light);
 	void setup_bind(Node *world_environment, Node *primary_light, Node *secondary_light);