merge `master` into `loek/savemgr`

75 files changed, 205 insertions, 215 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index de9e990..e4922df 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -37,6 +37,7 @@ install(
 )
 
 target_link_libraries(test_main
+	PRIVATE gtest
 	PRIVATE gtest_main
 	PUBLIC crepe
 )
diff --git a/src/crepe/CMakeLists.txt b/src/crepe/CMakeLists.txt
index 750a47d..3b05742 100644
--- a/src/crepe/CMakeLists.txt
+++ b/src/crepe/CMakeLists.txt
@@ -1,41 +1,23 @@
 target_sources(crepe PUBLIC
 	Asset.cpp
-	Sound.cpp
-	SoundContext.cpp
 	Particle.cpp
-	ParticleSystem.cpp
-	SDLApp.cpp
 	ComponentManager.cpp
 	Component.cpp
-	ScriptSystem.cpp
-	PhysicsSystem.cpp
-	CollisionSystem.cpp
 	Collider.cpp
-	SDLContext.cpp
-	RenderSystem.cpp
-	DB.cpp
 )
 
 target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	Asset.h
-	Sound.h
-	SoundContext.h
-	SDLContext.h
 	ComponentManager.h
 	ComponentManager.hpp
 	Component.h
-	System.h
-	ScriptSystem.h
-	PhysicsSystem.h
-	CollisionSystem.h
 	Collider.h
-	SDLContext.h
-	RenderSystem.h
 	ValueBroker.h
 	ValueBroker.hpp
-	DB.h
 )
 
 add_subdirectory(api)
+add_subdirectory(facade)
+add_subdirectory(system)
 add_subdirectory(util)
 
diff --git a/src/crepe/api/AssetManager.cpp b/src/crepe/api/AssetManager.cpp
index 560df6c..b891760 100644
--- a/src/crepe/api/AssetManager.cpp
+++ b/src/crepe/api/AssetManager.cpp
@@ -2,7 +2,7 @@
 
 #include "AssetManager.h"
 
-using namespace crepe::api;
+using namespace crepe;
 
 AssetManager & AssetManager::get_instance() {
 	static AssetManager instance;
diff --git a/src/crepe/api/AssetManager.h b/src/crepe/api/AssetManager.h
index 3e72a49..fefbed9 100644
--- a/src/crepe/api/AssetManager.h
+++ b/src/crepe/api/AssetManager.h
@@ -5,7 +5,7 @@
 #include <string>
 #include <unordered_map>
 
-namespace crepe::api {
+namespace crepe {
 
 class AssetManager {
 
@@ -30,6 +30,6 @@ public:
 								 bool reload = false);
 };
 
-} // namespace crepe::api
+} // namespace crepe
 
 #include "AssetManager.hpp"
diff --git a/src/crepe/api/AssetManager.hpp b/src/crepe/api/AssetManager.hpp
index 468724c..977b4e1 100644
--- a/src/crepe/api/AssetManager.hpp
+++ b/src/crepe/api/AssetManager.hpp
@@ -2,7 +2,7 @@
 
 #include "AssetManager.h"
 
-namespace crepe::api {
+namespace crepe {
 
 template <typename asset>
 std::shared_ptr<asset> AssetManager::cache(const std::string & file_path,
@@ -21,4 +21,4 @@ std::shared_ptr<asset> AssetManager::cache(const std::string & file_path,
 	return new_asset;
 }
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/AudioSource.cpp b/src/crepe/api/AudioSource.cpp
index 35b8d83..63fd0d7 100644
--- a/src/crepe/api/AudioSource.cpp
+++ b/src/crepe/api/AudioSource.cpp
@@ -1,10 +1,10 @@
 #include <memory>
 
-#include "../Sound.h"
+#include "../facade/Sound.h"
 
 #include "AudioSource.h"
 
-using namespace crepe::api;
+using namespace crepe;
 
 AudioSource::AudioSource(std::unique_ptr<Asset> audio_clip) {
 	this->sound = std::make_unique<crepe::Sound>(std::move(audio_clip));
diff --git a/src/crepe/api/AudioSource.h b/src/crepe/api/AudioSource.h
index 7980212..42add50 100644
--- a/src/crepe/api/AudioSource.h
+++ b/src/crepe/api/AudioSource.h
@@ -6,10 +6,8 @@
 #include "../Component.h"
 
 namespace crepe {
-class Sound;
-}
 
-namespace crepe::api {
+class Sound;
 
 //! Audio source component
 class AudioSource : Component {
@@ -35,7 +33,7 @@ public:
 	float volume;
 
 private:
-	std::unique_ptr<crepe::Sound> sound;
+	std::unique_ptr<Sound> sound;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/BehaviorScript.h b/src/crepe/api/BehaviorScript.h
index 6133cc8..21638f4 100644
--- a/src/crepe/api/BehaviorScript.h
+++ b/src/crepe/api/BehaviorScript.h
@@ -9,7 +9,7 @@ class ScriptSystem;
 class ComponentManager;
 } // namespace crepe
 
-namespace crepe::api {
+namespace crepe {
 
 class Script;
 
@@ -30,6 +30,6 @@ protected:
 	std::unique_ptr<Script> script = nullptr;
 };
 
-} // namespace crepe::api
+} // namespace crepe
 
 #include "BehaviorScript.hpp"
diff --git a/src/crepe/api/BehaviorScript.hpp b/src/crepe/api/BehaviorScript.hpp
index 2a3502f..4751607 100644
--- a/src/crepe/api/BehaviorScript.hpp
+++ b/src/crepe/api/BehaviorScript.hpp
@@ -7,7 +7,7 @@
 #include "BehaviorScript.h"
 #include "Script.h"
 
-namespace crepe::api {
+namespace crepe {
 
 template <class T>
 BehaviorScript & BehaviorScript::set_script() {
@@ -19,4 +19,4 @@ BehaviorScript & BehaviorScript::set_script() {
 	return *this;
 }
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/CircleCollider.h b/src/crepe/api/CircleCollider.h
index 762574b..931b012 100644
--- a/src/crepe/api/CircleCollider.h
+++ b/src/crepe/api/CircleCollider.h
@@ -1,7 +1,7 @@
 #pragma once
 #include "../Collider.h"
 
-namespace crepe::api {
+namespace crepe {
 
 class CircleCollider : public Collider {
 public:
@@ -10,4 +10,4 @@ public:
 	int radius;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Color.cpp b/src/crepe/api/Color.cpp
index fb5bd1a..fc6313d 100644
--- a/src/crepe/api/Color.cpp
+++ b/src/crepe/api/Color.cpp
@@ -1,6 +1,6 @@
 #include "Color.h"
 
-using namespace crepe::api;
+using namespace crepe;
 
 Color Color::white = Color(255, 255, 255, 0);
 Color Color::red = Color(255, 0, 0, 0);
diff --git a/src/crepe/api/Color.h b/src/crepe/api/Color.h
index e818de4..6b54888 100644
--- a/src/crepe/api/Color.h
+++ b/src/crepe/api/Color.h
@@ -1,6 +1,6 @@
 #pragma once
 
-namespace crepe::api {
+namespace crepe {
 
 class Color {
 
@@ -34,4 +34,4 @@ private:
 	static Color black;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Config.h b/src/crepe/api/Config.h
index aef4d54..4e6d1fa 100644
--- a/src/crepe/api/Config.h
+++ b/src/crepe/api/Config.h
@@ -2,7 +2,7 @@
 
 #include "../util/log.h"
 
-namespace crepe::api {
+namespace crepe {
 
 class Config {
 private:
@@ -27,7 +27,7 @@ public:
 		 * Only messages with equal or higher priority than this value will be
 		 * logged.
 		 */
-		util::LogLevel level = util::LogLevel::INFO;
+		LogLevel level = LogLevel::INFO;
 		/**
 		 * \brief Colored log output
 		 *
@@ -42,4 +42,4 @@ public:
 	} savemgr;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Force.cpp b/src/crepe/api/Force.cpp
index e359adc..3c33ad3 100644
--- a/src/crepe/api/Force.cpp
+++ b/src/crepe/api/Force.cpp
@@ -2,7 +2,7 @@
 
 #include "Force.h"
 
-namespace crepe::api {
+namespace crepe {
 
 Force::Force(uint32_t game_object_id, uint32_t magnitude, uint32_t direction)
 	: Component(game_object_id) {
@@ -18,4 +18,4 @@ Force::Force(uint32_t game_object_id, uint32_t magnitude, uint32_t direction)
 		std::round(magnitude * std::sin(radian_direction)));
 }
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Force.h b/src/crepe/api/Force.h
index 8da9a00..c08a8b9 100644
--- a/src/crepe/api/Force.h
+++ b/src/crepe/api/Force.h
@@ -4,7 +4,7 @@
 
 #include "../Component.h"
 
-namespace crepe::api {
+namespace crepe {
 
 class Force : public Component {
 public:
@@ -14,4 +14,4 @@ public:
 	int32_t force_y;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/GameObject.cpp b/src/crepe/api/GameObject.cpp
index b167187..445a60d 100644
--- a/src/crepe/api/GameObject.cpp
+++ b/src/crepe/api/GameObject.cpp
@@ -1,6 +1,6 @@
 #include "GameObject.h"
 
-using namespace crepe::api;
+using namespace crepe;
 using namespace std;
 
 GameObject::GameObject(uint32_t id, string name, string tag, int layer)
diff --git a/src/crepe/api/GameObject.h b/src/crepe/api/GameObject.h
index 57508c5..b5d6399 100644
--- a/src/crepe/api/GameObject.h
+++ b/src/crepe/api/GameObject.h
@@ -3,7 +3,7 @@
 #include <cstdint>
 #include <string>
 
-namespace crepe::api {
+namespace crepe {
 
 class GameObject {
 public:
@@ -19,6 +19,6 @@ public:
 	int layer;
 };
 
-} // namespace crepe::api
+} // namespace crepe
 
 #include "GameObject.hpp"
diff --git a/src/crepe/api/GameObject.hpp b/src/crepe/api/GameObject.hpp
index 3c7e867..77cf40e 100644
--- a/src/crepe/api/GameObject.hpp
+++ b/src/crepe/api/GameObject.hpp
@@ -4,7 +4,7 @@
 
 #include "GameObject.h"
 
-namespace crepe::api {
+namespace crepe {
 
 template <typename T, typename... Args>
 T & GameObject::add_component(Args &&... args) {
@@ -12,4 +12,4 @@ T & GameObject::add_component(Args &&... args) {
 	return mgr.add_component<T>(this->id, std::forward<Args>(args)...);
 }
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Point.h b/src/crepe/api/Point.h
index b47b7e6..575d624 100644
--- a/src/crepe/api/Point.h
+++ b/src/crepe/api/Point.h
@@ -1,6 +1,6 @@
 #pragma once
 
-namespace crepe::api {
+namespace crepe {
 
 class Point {
 public:
@@ -8,4 +8,4 @@ public:
 	double y;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Rigidbody.cpp b/src/crepe/api/Rigidbody.cpp
index ebf9fb9..0a6262a 100644
--- a/src/crepe/api/Rigidbody.cpp
+++ b/src/crepe/api/Rigidbody.cpp
@@ -1,6 +1,6 @@
 #include "Rigidbody.h"
 
-using namespace crepe::api;
+using namespace crepe;
 
 Rigidbody::Rigidbody(uint32_t game_object_id, int mass, int gravity_scale,
 					 BodyType bodyType)
diff --git a/src/crepe/api/Rigidbody.h b/src/crepe/api/Rigidbody.h
index 6079a76..518ed94 100644
--- a/src/crepe/api/Rigidbody.h
+++ b/src/crepe/api/Rigidbody.h
@@ -4,7 +4,7 @@
 
 #include "../Component.h"
 
-namespace crepe::api {
+namespace crepe {
 
 // FIXME: can't this enum be defined inside the class declaration of Rigidbody?
 enum class BodyType {
@@ -27,4 +27,4 @@ public:
 	BodyType body_type;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/SaveManager.cpp b/src/crepe/api/SaveManager.cpp
index 87e634b..d35fc7b 100644
--- a/src/crepe/api/SaveManager.cpp
+++ b/src/crepe/api/SaveManager.cpp
@@ -1,4 +1,4 @@
-#include "../DB.h"
+#include "../facade/DB.h"
 #include "../util/log.h"
 
 #include "Config.h"
@@ -7,7 +7,6 @@
 
 using namespace std;
 using namespace crepe;
-using namespace crepe::api;
 
 template <>
 string SaveManager::serialize(const string & value) {
diff --git a/src/crepe/api/SaveManager.h b/src/crepe/api/SaveManager.h
index a1f239d..035e2b7 100644
--- a/src/crepe/api/SaveManager.h
+++ b/src/crepe/api/SaveManager.h
@@ -5,10 +5,8 @@
 #include "../ValueBroker.h"
 
 namespace crepe {
-class DB;
-}
 
-namespace crepe::api {
+class DB;
 
 class SaveManager {
 public:
diff --git a/src/crepe/api/Script.cpp b/src/crepe/api/Script.cpp
index 5016ed0..390cec7 100644
--- a/src/crepe/api/Script.cpp
+++ b/src/crepe/api/Script.cpp
@@ -1,3 +1,3 @@
 #include "Script.h"
 
-using namespace crepe::api;
+using namespace crepe;
diff --git a/src/crepe/api/Script.h b/src/crepe/api/Script.h
index 59e6ec0..49e625f 100644
--- a/src/crepe/api/Script.h
+++ b/src/crepe/api/Script.h
@@ -6,7 +6,7 @@ namespace crepe {
 class ScriptSystem;
 }
 
-namespace crepe::api {
+namespace crepe {
 
 class BehaviorScript;
 
@@ -29,10 +29,10 @@ protected:
 	std::vector<std::reference_wrapper<T>> get_components();
 
 private:
-	friend class crepe::api::BehaviorScript;
+	friend class crepe::BehaviorScript;
 	BehaviorScript * parent = nullptr;
 };
 
-} // namespace crepe::api
+} // namespace crepe
 
 #include "Script.hpp"
diff --git a/src/crepe/api/Script.hpp b/src/crepe/api/Script.hpp
index 8004fe3..d96c0e8 100644
--- a/src/crepe/api/Script.hpp
+++ b/src/crepe/api/Script.hpp
@@ -5,7 +5,7 @@
 #include "BehaviorScript.h"
 #include "Script.h"
 
-namespace crepe::api {
+namespace crepe {
 
 template <typename T>
 T & Script::get_component() {
@@ -22,4 +22,4 @@ std::vector<std::reference_wrapper<T>> Script::get_components() {
 	return mgr.get_components_by_id<T>(this->parent->game_object_id);
 }
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Sprite.cpp b/src/crepe/api/Sprite.cpp
index 806f147..3dd44f2 100644
--- a/src/crepe/api/Sprite.cpp
+++ b/src/crepe/api/Sprite.cpp
@@ -1,15 +1,14 @@
 #include <cstdint>
 #include <memory>
 
-#include "api/Texture.h"
-#include "util/log.h"
+#include "../util/log.h"
 
 #include "Component.h"
 #include "Sprite.h"
+#include "Texture.h"
 
 using namespace std;
 using namespace crepe;
-using namespace crepe::api;
 
 Sprite::Sprite(uint32_t id, shared_ptr<Texture> image, const Color & color,
 			   const FlipSettings & flip)
diff --git a/src/crepe/api/Sprite.h b/src/crepe/api/Sprite.h
index b06125e..bdb4da9 100644
--- a/src/crepe/api/Sprite.h
+++ b/src/crepe/api/Sprite.h
@@ -9,7 +9,7 @@
 
 #include "Component.h"
 
-namespace crepe::api {
+namespace crepe {
 
 struct FlipSettings {
 	bool flip_x = 1;
@@ -29,4 +29,4 @@ public:
 	uint8_t order_in_layer;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Texture.cpp b/src/crepe/api/Texture.cpp
index 481ef7c..8fc5c13 100644
--- a/src/crepe/api/Texture.cpp
+++ b/src/crepe/api/Texture.cpp
@@ -1,12 +1,12 @@
 #include <SDL2/SDL_render.h>
 
-#include "util/log.h"
+#include "../facade/SDLContext.h"
+#include "../util/log.h"
 
 #include "Asset.h"
-#include "SDLContext.h"
 #include "Texture.h"
 
-using namespace crepe::api;
+using namespace crepe;
 using namespace std;
 
 Texture::Texture(unique_ptr<Asset> res) {
diff --git a/src/crepe/api/Texture.h b/src/crepe/api/Texture.h
index f8481e3..9a86f6f 100644
--- a/src/crepe/api/Texture.h
+++ b/src/crepe/api/Texture.h
@@ -12,7 +12,7 @@ namespace crepe {
 class SDLContext;
 }
 
-namespace crepe::api {
+namespace crepe {
 
 class Texture {
 
@@ -30,4 +30,4 @@ private:
 	friend class crepe::SDLContext;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/api/Transform.cpp b/src/crepe/api/Transform.cpp
index 3b218bc..70b16bd 100644
--- a/src/crepe/api/Transform.cpp
+++ b/src/crepe/api/Transform.cpp
@@ -6,9 +6,10 @@
 #include "Component.h"
 #include "Transform.h"
 
-using namespace crepe::api;
+using namespace crepe;
 
-Transform::Transform(uint32_t game_id, const Point & point, double rot, double scale)
+Transform::Transform(uint32_t game_id, const Point & point, double rot,
+					 double scale)
 	: Component(game_id), position(point), rotation(rot), scale(scale) {
 	dbg_trace();
 }
diff --git a/src/crepe/api/Transform.h b/src/crepe/api/Transform.h
index c451c16..d416088 100644
--- a/src/crepe/api/Transform.h
+++ b/src/crepe/api/Transform.h
@@ -6,7 +6,7 @@
 
 #include "Component.h"
 
-namespace crepe::api {
+namespace crepe {
 
 class Transform : public Component {
 	// FIXME: What's the difference between the `Point` and `Position`
@@ -24,4 +24,4 @@ public:
 	double scale;
 };
 
-} // namespace crepe::api
+} // namespace crepe
diff --git a/src/crepe/facade/CMakeLists.txt b/src/crepe/facade/CMakeLists.txt
new file mode 100644
index 0000000..bb52e7a
--- /dev/null
+++ b/src/crepe/facade/CMakeLists.txt
@@ -0,0 +1,16 @@
+target_sources(crepe PUBLIC
+	Sound.cpp
+	SoundContext.cpp
+	SDLApp.cpp
+	SDLContext.cpp
+	DB.cpp
+)
+
+target_sources(crepe PUBLIC FILE_SET HEADERS FILES
+	Sound.h
+	SoundContext.h
+	SDLContext.h
+	SDLContext.h
+	DB.h
+)
+
diff --git a/src/crepe/DB.cpp b/src/crepe/facade/DB.cpp
index bd2f089..bd2f089 100644
--- a/src/crepe/DB.cpp
+++ b/src/crepe/facade/DB.cpp
diff --git a/src/crepe/DB.h b/src/crepe/facade/DB.h
index 06442ad..06442ad 100644
--- a/src/crepe/DB.h
+++ b/src/crepe/facade/DB.h
diff --git a/src/crepe/SDLApp.cpp b/src/crepe/facade/SDLApp.cpp
index c6ddeaa..c6ddeaa 100644
--- a/src/crepe/SDLApp.cpp
+++ b/src/crepe/facade/SDLApp.cpp
diff --git a/src/crepe/SDLApp.h b/src/crepe/facade/SDLApp.h
index e67947b..6d8f3f4 100644
--- a/src/crepe/SDLApp.h
+++ b/src/crepe/facade/SDLApp.h
@@ -2,7 +2,7 @@
 
 #include <SDL2/SDL.h>
 
-#include "api/ParticleEmitter.h"
+#include "../api/ParticleEmitter.h"
 
 class SDLApp {
 public:
diff --git a/src/crepe/SDLContext.cpp b/src/crepe/facade/SDLContext.cpp
index 8bc5bc6..8da93e9 100644
--- a/src/crepe/SDLContext.cpp
+++ b/src/crepe/facade/SDLContext.cpp
@@ -7,10 +7,10 @@
 #include <cstddef>
 #include <iostream>
 
-#include "api/Sprite.h"
-#include "api/Texture.h"
-#include "api/Transform.h"
-#include "util/log.h"
+#include "../api/Sprite.h"
+#include "../api/Texture.h"
+#include "../api/Transform.h"
+#include "../util/log.h"
 
 #include "SDLContext.h"
 
@@ -89,8 +89,7 @@ SDLContext::SDLContext() {
 
 void SDLContext::present_screen() { SDL_RenderPresent(this->game_renderer); }
 
-void SDLContext::draw(const api::Sprite & sprite,
-					  const api::Transform & transform) {
+void SDLContext::draw(const Sprite & sprite, const Transform & transform) {
 
 	static SDL_RendererFlip render_flip
 		= (SDL_RendererFlip) ((SDL_FLIP_HORIZONTAL * sprite.flip.flip_x)
diff --git a/src/crepe/SDLContext.h b/src/crepe/facade/SDLContext.h
index 4d9c1bc..f1ba8a6 100644
--- a/src/crepe/SDLContext.h
+++ b/src/crepe/facade/SDLContext.h
@@ -3,17 +3,13 @@
 #include <SDL2/SDL_render.h>
 #include <SDL2/SDL_video.h>
 
-#include "api/Sprite.h"
-#include "api/Transform.h"
-
-#include "RenderSystem.h"
-
-namespace crepe::api {
-class Texture;
-}
+#include "../api/Sprite.h"
+#include "../api/Transform.h"
+#include "../system/RenderSystem.h"
 
 namespace crepe {
 
+class Texture;
 class SDLContext {
 
 public:
@@ -34,13 +30,13 @@ private:
 	virtual ~SDLContext();
 
 private:
-	friend class api::Texture;
+	friend class Texture;
 	SDL_Texture * texture_from_path(const char *);
 	//SDL_Texture* setTextureFromPath(const char*, SDL_Rect& clip, const int row, const int col);
 
 private:
 	friend class RenderSystem;
-	void draw(const api::Sprite &, const api::Transform &);
+	void draw(const Sprite &, const Transform &);
 	void clear_screen();
 	void present_screen();
 
diff --git a/src/crepe/Sound.cpp b/src/crepe/facade/Sound.cpp
index 64fa281..648ec81 100644
--- a/src/crepe/Sound.cpp
+++ b/src/crepe/facade/Sound.cpp
@@ -1,4 +1,4 @@
-#include "util/log.h"
+#include "../util/log.h"
 
 #include "Sound.h"
 #include "SoundContext.h"
diff --git a/src/crepe/Sound.h b/src/crepe/facade/Sound.h
index 917b57e..183bd7c 100644
--- a/src/crepe/Sound.h
+++ b/src/crepe/facade/Sound.h
@@ -4,7 +4,7 @@
 #include <soloud/soloud.h>
 #include <soloud/soloud_wav.h>
 
-#include "Asset.h"
+#include "../Asset.h"
 
 namespace crepe {
 
diff --git a/src/crepe/SoundContext.cpp b/src/crepe/facade/SoundContext.cpp
index 72047d2..5e5a3a9 100644
--- a/src/crepe/SoundContext.cpp
+++ b/src/crepe/facade/SoundContext.cpp
@@ -1,4 +1,4 @@
-#include "util/log.h"
+#include "../util/log.h"
 
 #include "SoundContext.h"
 
diff --git a/src/crepe/SoundContext.h b/src/crepe/facade/SoundContext.h
index d3123d2..d3123d2 100644
--- a/src/crepe/SoundContext.h
+++ b/src/crepe/facade/SoundContext.h
diff --git a/src/crepe/system/CMakeLists.txt b/src/crepe/system/CMakeLists.txt
new file mode 100644
index 0000000..ff6f66f
--- /dev/null
+++ b/src/crepe/system/CMakeLists.txt
@@ -0,0 +1,15 @@
+target_sources(crepe PUBLIC
+	ParticleSystem.cpp
+	ScriptSystem.cpp
+	PhysicsSystem.cpp
+	CollisionSystem.cpp
+	RenderSystem.cpp
+)
+
+target_sources(crepe PUBLIC FILE_SET HEADERS FILES
+	System.h
+	ScriptSystem.h
+	PhysicsSystem.h
+	CollisionSystem.h
+	RenderSystem.h
+)
diff --git a/src/crepe/CollisionSystem.cpp b/src/crepe/system/CollisionSystem.cpp
index 55e0fdc..55e0fdc 100644
--- a/src/crepe/CollisionSystem.cpp
+++ b/src/crepe/system/CollisionSystem.cpp
diff --git a/src/crepe/CollisionSystem.h b/src/crepe/system/CollisionSystem.h
index 1e9f1aa..1e9f1aa 100644
--- a/src/crepe/CollisionSystem.h
+++ b/src/crepe/system/CollisionSystem.h
diff --git a/src/crepe/ParticleSystem.cpp b/src/crepe/system/ParticleSystem.cpp
index af6c550..397b586 100644
--- a/src/crepe/ParticleSystem.cpp
+++ b/src/crepe/system/ParticleSystem.cpp
@@ -1,9 +1,9 @@
 #include <cmath>
 #include <ctime>
 
-#include "api/ParticleEmitter.h"
+#include "../ComponentManager.h"
+#include "../api/ParticleEmitter.h"
 
-#include "ComponentManager.h"
 #include "ParticleSystem.h"
 
 using namespace crepe;
diff --git a/src/crepe/ParticleSystem.h b/src/crepe/system/ParticleSystem.h
index ad96eb0..3ac1d3f 100644
--- a/src/crepe/ParticleSystem.h
+++ b/src/crepe/system/ParticleSystem.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "api/ParticleEmitter.h"
+#include "../api/ParticleEmitter.h"
 
 namespace crepe {
 
diff --git a/src/crepe/PhysicsSystem.cpp b/src/crepe/system/PhysicsSystem.cpp
index 16f4c10..cea8062 100644
--- a/src/crepe/PhysicsSystem.cpp
+++ b/src/crepe/system/PhysicsSystem.cpp
@@ -1,14 +1,13 @@
 #include <iostream>
 
-#include "api/Force.h"
-#include "api/Rigidbody.h"
-#include "api/Transform.h"
+#include "../ComponentManager.h"
+#include "../api/Force.h"
+#include "../api/Rigidbody.h"
+#include "../api/Transform.h"
 
-#include "ComponentManager.h"
 #include "PhysicsSystem.h"
 
 using namespace crepe;
-using namespace crepe::api;
 
 PhysicsSystem::PhysicsSystem() {}
 
diff --git a/src/crepe/PhysicsSystem.h b/src/crepe/system/PhysicsSystem.h
index 33b4072..33b4072 100644
--- a/src/crepe/PhysicsSystem.h
+++ b/src/crepe/system/PhysicsSystem.h
diff --git a/src/crepe/RenderSystem.cpp b/src/crepe/system/RenderSystem.cpp
index fae93f0..96c94e9 100644
--- a/src/crepe/RenderSystem.cpp
+++ b/src/crepe/system/RenderSystem.cpp
@@ -1,16 +1,15 @@
 #include <functional>
 #include <vector>
 
-#include "api/Sprite.h"
-#include "api/Transform.h"
-#include "util/log.h"
+#include "../ComponentManager.h"
+#include "../facade/SDLContext.h"
+#include "../api/Sprite.h"
+#include "../api/Transform.h"
+#include "../util/log.h"
 
-#include "ComponentManager.h"
 #include "RenderSystem.h"
-#include "SDLContext.h"
 
 using namespace crepe;
-using namespace crepe::api;
 
 RenderSystem::RenderSystem() { dbg_trace(); }
 
diff --git a/src/crepe/RenderSystem.h b/src/crepe/system/RenderSystem.h
index 4b910a4..4b910a4 100644
--- a/src/crepe/RenderSystem.h
+++ b/src/crepe/system/RenderSystem.h
diff --git a/src/crepe/ScriptSystem.cpp b/src/crepe/system/ScriptSystem.cpp
index 171b490..f1fae4d 100644
--- a/src/crepe/ScriptSystem.cpp
+++ b/src/crepe/system/ScriptSystem.cpp
@@ -2,16 +2,15 @@
 #include <functional>
 #include <vector>
 
-#include "api/BehaviorScript.h"
-#include "api/Script.h"
-#include "util/log.h"
+#include "../ComponentManager.h"
+#include "../api/BehaviorScript.h"
+#include "../api/Script.h"
+#include "../util/log.h"
 
-#include "ComponentManager.h"
 #include "ScriptSystem.h"
 
 using namespace std;
 using namespace crepe;
-using namespace crepe::api;
 
 ScriptSystem::ScriptSystem() { dbg_trace(); }
 ScriptSystem::~ScriptSystem() { dbg_trace(); }
diff --git a/src/crepe/ScriptSystem.h b/src/crepe/system/ScriptSystem.h
index 1f472a0..32e793c 100644
--- a/src/crepe/ScriptSystem.h
+++ b/src/crepe/system/ScriptSystem.h
@@ -4,12 +4,10 @@
 
 #include "System.h"
 
-namespace crepe::api {
-class Script;
-}
-
 namespace crepe {
 
+class Script;
+
 class ScriptSystem : public System {
 public:
 	static ScriptSystem & get_instance();
@@ -20,7 +18,8 @@ private:
 	~ScriptSystem();
 
 private:
-	std::forward_list<api::Script *> get_scripts();
+	// TODO: to forward_list<reference_wrapper>
+	std::forward_list<Script *> get_scripts();
 };
 
 } // namespace crepe
diff --git a/src/crepe/System.h b/src/crepe/system/System.h
index ecbb7f5..ecbb7f5 100644
--- a/src/crepe/System.h
+++ b/src/crepe/system/System.h
diff --git a/src/crepe/util/CMakeLists.txt b/src/crepe/util/CMakeLists.txt
index 01d8f22..0fa4343 100644
--- a/src/crepe/util/CMakeLists.txt
+++ b/src/crepe/util/CMakeLists.txt
@@ -1,11 +1,11 @@
 target_sources(crepe PUBLIC
-	color.cpp
+	LogColor.cpp
 	log.cpp
 	fmt.cpp
 )
 
 target_sources(crepe PUBLIC FILE_SET HEADERS FILES
-	color.h
+	LogColor.h
 	log.h
 	fmt.h
 	Proxy.h
diff --git a/src/crepe/util/color.cpp b/src/crepe/util/LogColor.cpp
index a7bbc81..b5fe3ea 100644
--- a/src/crepe/util/color.cpp
+++ b/src/crepe/util/LogColor.cpp
@@ -1,16 +1,17 @@
 #include <cstdarg>
 
 #include "../api/Config.h"
-#include "color.h"
+#include "LogColor.h"
+
 #include "fmt.h"
 
-using namespace crepe::util;
+using namespace crepe;
 using namespace std;
 
 static constexpr const char * RESET_CODE = "\e[0m";
 
 const string LogColor::str(const string & content) {
-	auto & cfg = api::Config::get_instance();
+	auto & cfg = Config::get_instance();
 	string out = content;
 	if (cfg.log.color) out = this->code + out;
 	if (content.size() == 0) return out;
diff --git a/src/crepe/util/color.h b/src/crepe/util/LogColor.h
index 91e1abe..c1170cb 100644
--- a/src/crepe/util/color.h
+++ b/src/crepe/util/LogColor.h
@@ -2,7 +2,7 @@
 
 #include <string>
 
-namespace crepe::util {
+namespace crepe {
 
 class LogColor {
 public:
@@ -48,4 +48,4 @@ private:
 	std::string final = "";
 };
 
-} // namespace crepe::util
+} // namespace crepe
diff --git a/src/crepe/util/Proxy.h b/src/crepe/util/Proxy.h
index 89cb3c3..65db04d 100644
--- a/src/crepe/util/Proxy.h
+++ b/src/crepe/util/Proxy.h
@@ -2,13 +2,13 @@
 
 #include "ValueBroker.h"
 
-namespace crepe::util {
+namespace crepe {
 
 template <typename T>
 class Proxy {
 public:
 	Proxy & operator = (const T &);
-	operator const T & () const;
+	operator const T & ();
 
 public:
 	Proxy(ValueBroker<T>);
diff --git a/src/crepe/util/Proxy.hpp b/src/crepe/util/Proxy.hpp
index c2cae93..4aec9e9 100644
--- a/src/crepe/util/Proxy.hpp
+++ b/src/crepe/util/Proxy.hpp
@@ -2,7 +2,7 @@
 
 #include "Proxy.h"
 
-namespace crepe::util {
+namespace crepe {
 
 template <typename T>
 Proxy<T>::Proxy(ValueBroker<T> broker) : broker(broker) { }
@@ -14,7 +14,7 @@ Proxy<T> & Proxy<T>::operator = (const T & val) {
 }
 
 template <typename T>
-Proxy<T>::operator const T & () const {
+Proxy<T>::operator const T & () {
 	return this->broker.get();
 }
 
diff --git a/src/crepe/util/fmt.cpp b/src/crepe/util/fmt.cpp
index 8ef1164..4b50da8 100644
--- a/src/crepe/util/fmt.cpp
+++ b/src/crepe/util/fmt.cpp
@@ -6,25 +6,27 @@
 
 using namespace std;
 
-string crepe::util::va_stringf(va_list args, const char * fmt) {
+string crepe::va_stringf(va_list args, const char * fmt) {
+	string out;
+
 	va_list args_copy;
 	va_copy(args_copy, args);
-
-	size_t sz = vsnprintf(NULL, 0, fmt, args_copy) + 1;
-	char * msg = (char *) malloc(sz);
+	size_t length = vsnprintf(NULL, 0, fmt, args_copy);
+	// resize to include terminating null byte
+	out.resize(length + 1);
 	va_end(args_copy);
 
-	vsnprintf(msg, sz, fmt, args);
-
-	string out = msg;
-	free(msg);
+	// vsnprintf adds terminating null byte
+	vsnprintf(out.data(), out.size(), fmt, args);
+	// resize to actual length
+	out.resize(length);
 
 	va_end(args);
 
 	return out;
 }
 
-string crepe::util::stringf(const char * fmt, ...) {
+string crepe::stringf(const char * fmt, ...) {
 	va_list args;
 	va_start(args, fmt);
 	string out = va_stringf(args, fmt);
diff --git a/src/crepe/util/fmt.h b/src/crepe/util/fmt.h
index 44c426f..e319e6e 100644
--- a/src/crepe/util/fmt.h
+++ b/src/crepe/util/fmt.h
@@ -2,9 +2,9 @@
 
 #include <string>
 
-namespace crepe::util {
+namespace crepe {
 
 std::string va_stringf(va_list args, const char * fmt);
 std::string stringf(const char * fmt, ...);
 
-} // namespace crepe::util
+} // namespace crepe
diff --git a/src/crepe/util/log.cpp b/src/crepe/util/log.cpp
index 6bcc4ae..4a8f8e8 100644
--- a/src/crepe/util/log.cpp
+++ b/src/crepe/util/log.cpp
@@ -7,7 +7,7 @@
 #include "fmt.h"
 #include "log.h"
 
-using namespace crepe::util;
+using namespace crepe;
 using namespace std;
 
 string log_prefix(LogLevel level) {
@@ -27,25 +27,25 @@ string log_prefix(LogLevel level) {
 }
 
 static void log(LogLevel level, const string msg) {
-	auto & cfg = crepe::api::Config::get_instance();
+	auto & cfg = Config::get_instance();
 	if (level < cfg.log.level) return;
 
 	string out = log_prefix(level) + msg;
 	if (!out.ends_with("\n")) out += "\n";
 
 	// TODO: also log to file or smth
-	printf("%s", out.c_str());
+	fwrite(out.c_str(), 1, out.size(), stdout);
 	fflush(stdout);
 }
 
-void crepe::util::logf(const char * fmt, ...) {
+void crepe::logf(const char * fmt, ...) {
 	va_list args;
 	va_start(args, fmt);
 	log(LogLevel::DEBUG, va_stringf(args, fmt));
 	va_end(args);
 }
 
-void crepe::util::logf(LogLevel level, const char * fmt, ...) {
+void crepe::logf(LogLevel level, const char * fmt, ...) {
 	va_list args;
 	va_start(args, fmt);
 	log(level, va_stringf(args, fmt));
diff --git a/src/crepe/util/log.h b/src/crepe/util/log.h
index 308ba96..5a1cf00 100644
--- a/src/crepe/util/log.h
+++ b/src/crepe/util/log.h
@@ -3,28 +3,27 @@
 // allow user to disable debug macros
 #ifndef CREPE_DISABLE_MACROS
 
-#include "color.h"
+#include "LogColor.h"
 
 // utility macros
 #define _crepe_logf_here(level, format, ...) \
-	crepe::util::logf( \
+	crepe::logf( \
 		level, "%s" format, \
-		crepe::util::LogColor().fg_white(false).fmt( \
+		crepe::LogColor().fg_white(false).fmt( \
 			"%s (%s:%d)", __PRETTY_FUNCTION__, __FILE_NAME__, __LINE__), \
 		__VA_ARGS__)
 
 // very illegal global function-style macros
 // NOLINTBEGIN
 #define dbg_logf(fmt, ...) \
-	_crepe_logf_here(crepe::util::LogLevel::DEBUG, ": " fmt, __VA_ARGS__)
-#define dbg_log(str) \
-	_crepe_logf_here(crepe::util::LogLevel::DEBUG, "%s: " str, "")
-#define dbg_trace() _crepe_logf_here(crepe::util::LogLevel::TRACE, "%s", "")
+	_crepe_logf_here(crepe::LogLevel::DEBUG, ": " fmt, __VA_ARGS__)
+#define dbg_log(str) _crepe_logf_here(crepe::LogLevel::DEBUG, "%s: " str, "")
+#define dbg_trace() _crepe_logf_here(crepe::LogLevel::TRACE, "%s", "")
 // NOLINTEND
 
 #endif
 
-namespace crepe::util {
+namespace crepe {
 
 enum LogLevel {
 	TRACE,
@@ -37,4 +36,4 @@ enum LogLevel {
 void logf(const char * fmt, ...);
 void logf(enum LogLevel level, const char * fmt, ...);
 
-} // namespace crepe::util
+} // namespace crepe
diff --git a/src/example/asset_manager.cpp b/src/example/asset_manager.cpp
index 7e15d1f..ba18b62 100644
--- a/src/example/asset_manager.cpp
+++ b/src/example/asset_manager.cpp
@@ -1,11 +1,9 @@
-
-
-#include <crepe/Sound.h>
+#include <crepe/facade/Sound.h>
 #include <crepe/api/AssetManager.h>
 #include <crepe/api/Texture.h>
 
 using namespace crepe;
-using namespace crepe::api;
+
 int main() {
 
 	// this needs to be called before the asset manager otherwise the destructor
diff --git a/src/example/audio_internal.cpp b/src/example/audio_internal.cpp
index f35ad9d..0b36daa 100644
--- a/src/example/audio_internal.cpp
+++ b/src/example/audio_internal.cpp
@@ -3,29 +3,26 @@
  * Standalone example for usage of the internal \c Sound class.
  */
 
-#include <crepe/Sound.h>
-#include <crepe/util/log.h>
+#include <crepe/facade/Sound.h>
 #include <crepe/api/Config.h>
+#include <crepe/util/log.h>
 
 #include <thread>
 
 using namespace crepe;
-using namespace crepe::api;
 using namespace std;
 using namespace std::chrono_literals;
 using std::make_unique;
 
 // Unrelated stuff that is not part of this POC
-int _ = [] () {
+int _ = []() {
 	// Show dbg_trace() output
-	auto & cfg = api::Config::get_instance();
-	cfg.log.level = util::LogLevel::TRACE;
+	auto & cfg = Config::get_instance();
+	cfg.log.level = LogLevel::TRACE;
 
 	return 0; // satisfy compiler
 }();
 
-
-
 int main() {
 	// Load a background track (Ogg Vorbis)
 	auto bgm = Sound("../mwe/audio/bgm.ogg");
diff --git a/src/example/components_internal.cpp b/src/example/components_internal.cpp
index 3c68974..ea1eaad 100644
--- a/src/example/components_internal.cpp
+++ b/src/example/components_internal.cpp
@@ -15,7 +15,6 @@
 
 #include <crepe/util/log.h>
 
-using namespace crepe::api;
 using namespace crepe;
 using namespace std;
 
diff --git a/src/example/db.cpp b/src/example/db.cpp
index b1ab196..c046421 100644
--- a/src/example/db.cpp
+++ b/src/example/db.cpp
@@ -1,4 +1,4 @@
-#include <crepe/DB.h>
+#include <crepe/facade/DB.h>
 #include <crepe/api/Config.h>
 #include <crepe/util/log.h>
 
@@ -7,8 +7,8 @@ using namespace std;
 
 // run before main
 static auto _ = [] () {
-	auto & cfg = api::Config::get_instance();
-	cfg.log.level = util::LogLevel::TRACE;
+	auto & cfg = Config::get_instance();
+	cfg.log.level = LogLevel::TRACE;
 	return 0;
 }();
 
diff --git a/src/example/log.cpp b/src/example/log.cpp
index 04ab9cd..db8aa48 100644
--- a/src/example/log.cpp
+++ b/src/example/log.cpp
@@ -7,16 +7,15 @@
 #include <crepe/util/log.h>
 
 using namespace crepe;
-using namespace crepe::util;
 
 // unrelated setup code
-int _ = [] () {
+int _ = []() {
 	// make sure all log messages get printed
-	auto & cfg = api::Config::get_instance();
-	cfg.log.level = util::LogLevel::TRACE;
+	auto & cfg = Config::get_instance();
+	cfg.log.level = LogLevel::TRACE;
 
 	return 0; // satisfy compiler
-} ();
+}();
 
 int main() {
 	dbg_trace();
diff --git a/src/example/particle.cpp b/src/example/particle.cpp
index 53fa213..83b1e8a 100644
--- a/src/example/particle.cpp
+++ b/src/example/particle.cpp
@@ -1,15 +1,15 @@
-#include "Particle.h"
-#include "ParticleSystem.h"
-#include "SDLApp.h"
-#include "api/ParticleEmitter.h"
 #include <chrono>
+#include <iostream>
+#include <thread>
+
 #include <crepe/Component.h>
 #include <crepe/ComponentManager.h>
+#include <crepe/Particle.h>
+#include <crepe/facade/SDLApp.h>
 #include <crepe/api/GameObject.h>
-#include <iostream>
-#include <thread>
+#include <crepe/api/ParticleEmitter.h>
+#include <crepe/system/ParticleSystem.h>
 
-using namespace crepe::api;
 using namespace crepe;
 using namespace std;
 
diff --git a/src/example/physics.cpp b/src/example/physics.cpp
index db69b9b..2dbddc2 100644
--- a/src/example/physics.cpp
+++ b/src/example/physics.cpp
@@ -1,15 +1,15 @@
-#include "PhysicsSystem.h"
 #include <chrono>
+#include <iostream>
+#include <thread>
+
 #include <crepe/Component.h>
 #include <crepe/ComponentManager.h>
 #include <crepe/api/Force.h>
 #include <crepe/api/GameObject.h>
 #include <crepe/api/Rigidbody.h>
 #include <crepe/api/Transform.h>
-#include <iostream>
-#include <thread>
+#include <crepe/system/PhysicsSystem.h>
 
-using namespace crepe::api;
 using namespace crepe;
 using namespace std;
 
diff --git a/src/example/proxy.cpp b/src/example/proxy.cpp
index 0be4fac..9f54f96 100644
--- a/src/example/proxy.cpp
+++ b/src/example/proxy.cpp
@@ -3,22 +3,21 @@
  * Standalone example for usage of the proxy type
  */
 
-#include "ValueBroker.h"
+#include <crepe/ValueBroker.h>
 #include <crepe/api/Config.h>
 #include <crepe/util/log.h>
 #include <crepe/util/Proxy.h>
 
 using namespace std;
 using namespace crepe;
-using namespace crepe::util;
 
 void test_ro_ref(const int & val) { }
 void test_rw_ref(int & val) { }
 void test_ro_val(int val) { }
 
 int main() {
-	auto & cfg = api::Config::get_instance();
-	cfg.log.level = util::LogLevel::DEBUG;
+	auto & cfg = Config::get_instance();
+	cfg.log.level = LogLevel::DEBUG;
 
 	int real_value = 0;
 
diff --git a/src/example/rendering.cpp b/src/example/rendering.cpp
index 1bf448c..b0ab60a 100644
--- a/src/example/rendering.cpp
+++ b/src/example/rendering.cpp
@@ -1,8 +1,6 @@
-
-
 #include <crepe/ComponentManager.h>
-#include <crepe/RenderSystem.h>
 #include <crepe/api/GameObject.h>
+#include <crepe/system/RenderSystem.h>
 #include <crepe/util/log.h>
 
 #include <crepe/api/AssetManager.h>
@@ -17,7 +15,6 @@
 
 using namespace std;
 using namespace crepe;
-using namespace crepe::api;
 
 int main() {
 
diff --git a/src/example/savemgr.cpp b/src/example/savemgr.cpp
index 6d011e5..c8dd2bc 100644
--- a/src/example/savemgr.cpp
+++ b/src/example/savemgr.cpp
@@ -10,14 +10,12 @@
 #include <crepe/api/Config.h>
 
 using namespace crepe;
-using namespace crepe::api;
-using namespace crepe::util;
 
 // unrelated setup code
 int _ = [] () {
 	// make sure all log messages get printed
 	auto & cfg = Config::get_instance();
-	cfg.log.level = util::LogLevel::TRACE;
+	cfg.log.level = LogLevel::TRACE;
 
 	return 0; // satisfy compiler
 } ();
diff --git a/src/example/script.cpp b/src/example/script.cpp
index cda9591..dac7af3 100644
--- a/src/example/script.cpp
+++ b/src/example/script.cpp
@@ -4,7 +4,7 @@
  */
 
 #include <crepe/ComponentManager.h>
-#include <crepe/ScriptSystem.h>
+#include <crepe/system/ScriptSystem.h>
 #include <crepe/util/log.h>
 
 #include <crepe/api/BehaviorScript.h>
@@ -14,20 +14,17 @@
 #include <crepe/api/Transform.h>
 
 using namespace crepe;
-using namespace crepe::api;
 using namespace std;
 
 // Unrelated stuff that is not part of this POC
-int _ = [] () {
+int _ = []() {
 	// Show dbg_trace() output
-	auto & cfg = api::Config::get_instance();
-	cfg.log.level = util::LogLevel::TRACE;
+	auto & cfg = Config::get_instance();
+	cfg.log.level = LogLevel::TRACE;
 
 	return 0; // satisfy compiler
 }();
 
-
-
 // User-defined script:
 class MyScript : public Script {
 	void update() {
@@ -40,7 +37,12 @@ class MyScript : public Script {
 int main() {
 	// Create game object with Transform and BehaviorScript components
 	auto obj = GameObject(0, "name", "tag", 0);
-	obj.add_component<Transform>(Point { .x = 1.2, .y = 3.4, }, 0, 0);
+	obj.add_component<Transform>(
+		Point{
+			.x = 1.2,
+			.y = 3.4,
+		},
+		0, 0);
 	obj.add_component<BehaviorScript>().set_script<MyScript>();
 
 	// Get ScriptSystem singleton instance (this would normally be done from the
@@ -51,4 +53,3 @@ int main() {
 
 	return EXIT_SUCCESS;
 }
-