Merge remote-tracking branch 'origin/master' into max/big-cleanup

10 files changed, 342 insertions, 6 deletions

diff --git a/contributing.md b/contributing.md
index 88cba32..cd1b6a6 100644
--- a/contributing.md
+++ b/contributing.md
@@ -49,12 +49,11 @@ that you can click on to open them.
   class Cars {};
   ```
   </td></tr></table></details>
-- Source files (.cpp, .hpp) contain the following types of comments:
+- Source files (`.cpp`, `.hpp`) contain the following types of comments:
   - What is the code supposed to do (optional)
   - Implementation details (if applicable)
-- Header files (.h) contain the following types of comments:
-  - Usage documentation (required)
-
+- Header files (`.h`) contain the following types of comments:
+  - [Usage documentation](#documentation) (required)
     > [!NOTE]
     > Constructors/destructors aren't required to have a `\brief` description
   - Implementation details (if they affect the header)
@@ -421,6 +420,127 @@ that you can click on to open them.
   void bar(Point p);
   ```
   </td></tr></table></details>
+- <details><summary>
+  Follow the rule of five
+  </summary><table><tr><th>Good</th><th>Bad</th></tr><tr><td>
+
+  ```cpp
+  class Foo {
+  public:
+    Foo();
+    ~Foo();
+    Foo(Foo &&) noexcept;
+    Foo & operator = (const Foo &);
+    Foo & operator = (Foo &&) noexcept;
+  };
+  ```
+  </td><td>
+
+  ```cpp
+  class Foo {
+  public:
+    Foo();
+    ~Foo();
+  };
+  ```
+  </td></tr></table></details>
+- <details><summary>
+  Ensure const-correctness
+  </summary><table><tr><th>Good</th><th>Bad</th></tr><tr><td>
+
+  ```cpp
+  class Foo {
+  public:
+    int get_value() const;
+    void set_value(int new_value);
+    const std::string & get_name() const;
+    void set_name(const std::string & new_name);
+  private:
+    int value;
+    std::string name;
+  };
+  ```
+  </td><td>
+
+  ```cpp
+  class Foo {
+  public:
+    int get_value();
+    void set_value(int new_value);
+    std::string get_name();
+    void set_name(std::string new_name);
+  private:
+    int value;
+    std::string name;
+  };
+  ```
+  </td></tr></table></details>
+- <details><summary>
+  Files should be named after the class/struct/interface they implement
+  </summary><table><tr><th>Good</th><th>Bad</th></tr><tr><td>
+
+  ```cpp
+  MyClass.h
+  MyClass.cpp
+  MyClass.hpp
+  ```
+  </td><td>
+
+  ```cpp
+  my_class.h
+  myClass.cpp
+  my-class.hpp
+  ```
+  </td></tr></table></details>
+- <details><summary>
+  Implementations are not allowed in header files, except if the implementation
+
+  - is `= default`
+  - is `= delete`
+  - is `{}` (empty)
+  - only returns a constant literal
+  </summary><table><tr><th>Good</th><th>Bad</th></tr><tr><td>
+
+  ```cpp
+  class Foo {
+  public:
+    int get_value() const { return 42; }
+  };
+  ```
+  </td><td>
+
+  ```cpp
+  class Foo {
+  public:
+    int calculate_value() const {
+      int result = 0;
+      // complex calculation
+      return result;
+    }
+  };
+  ```
+  </td></tr></table></details>
+- <details><summary>
+  Use angle brackets (<code><></code>) only for including system headers and
+  double quotes (<code>""</code>) for including other engine files.
+
+  > [!NOTE]
+  > Only files in the examples folder should include engine headers with angle
+  > brackets
+  </summary><table><tr><th>Good</th><th>Bad</th></tr><tr><td>
+
+  ```cpp
+  #include <iostream>
+
+  #include "facade/Sound.h"
+  ```
+  </td><td>
+
+  ```cpp
+  #include <iostream>
+  #include <crepe/facade/Sound.h>
+  ```
+  </td></tr></table></details>
 
 ## CMakeLists-specific
 
diff --git a/src/crepe/ComponentManager.hpp b/src/crepe/ComponentManager.hpp
index e52b679..7616f92 100644
--- a/src/crepe/ComponentManager.hpp
+++ b/src/crepe/ComponentManager.hpp
@@ -88,7 +88,8 @@ ComponentManager::get_components_by_id(uint32_t id) const {
 	// Create an empty vector<>
 	vector<reference_wrapper<T>> component_vector;
 
-	if (this->components.find(type) == this->components.end()) return component_vector;
+	if (this->components.find(type) == this->components.end())
+		return component_vector;
 
 	// Get the correct vector<>
 	const vector<vector<unique_ptr<Component>>> & component_array
@@ -123,7 +124,8 @@ ComponentManager::get_components_by_type() const {
 	vector<reference_wrapper<T>> component_vector;
 
 	// Find the type (in the unordered_map<>)
-	if (this->components.find(type) == this->components.end()) return component_vector;
+	if (this->components.find(type) == this->components.end())
+		return component_vector;
 
 	// Get the correct vector<>
 	const vector<vector<unique_ptr<Component>>> & component_array
diff --git a/src/crepe/api/CMakeLists.txt b/src/crepe/api/CMakeLists.txt
index 3e0c044..dbd6bf1 100644
--- a/src/crepe/api/CMakeLists.txt
+++ b/src/crepe/api/CMakeLists.txt
@@ -12,6 +12,8 @@ target_sources(crepe PUBLIC
 	AssetManager.cpp
 	Sprite.cpp
 	Metadata.cpp
+	Scene.cpp
+	SceneManager.cpp
 )
 
 target_sources(crepe PUBLIC FILE_SET HEADERS FILES
@@ -29,5 +31,8 @@ target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	Texture.h 
 	AssetManager.h 
 	AssetManager.hpp
+	Scene.h
 	Metadata.h
+	SceneManager.h
+	SceneManager.hpp
 )
diff --git a/src/crepe/api/Scene.cpp b/src/crepe/api/Scene.cpp
new file mode 100644
index 0000000..933edf4
--- /dev/null
+++ b/src/crepe/api/Scene.cpp
@@ -0,0 +1,5 @@
+#include "Scene.h"
+
+using namespace crepe;
+
+Scene::Scene(const std::string & name) : name(name) {}
diff --git a/src/crepe/api/Scene.h b/src/crepe/api/Scene.h
new file mode 100644
index 0000000..f8bcc3d
--- /dev/null
+++ b/src/crepe/api/Scene.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <string>
+
+namespace crepe {
+
+class Scene {
+public:
+	Scene(const std::string & name);
+	virtual ~Scene() = default;
+	virtual void load_scene() = 0;
+
+public:
+	std::string name;
+};
+
+} // namespace crepe
diff --git a/src/crepe/api/SceneManager.cpp b/src/crepe/api/SceneManager.cpp
new file mode 100644
index 0000000..57ec302
--- /dev/null
+++ b/src/crepe/api/SceneManager.cpp
@@ -0,0 +1,43 @@
+#include <algorithm>
+#include <memory>
+
+#include "../ComponentManager.h"
+
+#include "SceneManager.h"
+
+using namespace crepe;
+using namespace std;
+
+SceneManager & SceneManager::get_instance() {
+	static SceneManager instance;
+	return instance;
+}
+
+void SceneManager::set_next_scene(const string & name) {
+	next_scene = name;
+}
+
+void SceneManager::load_next_scene() {
+	// next scene not set
+	if (this->next_scene.empty())
+		return;
+
+	auto it = find_if(this->scenes.begin(), this->scenes.end(),
+		[&next_scene = this->next_scene] (unique_ptr<Scene> & scene) {
+			return scene->name == next_scene;
+		}
+	);
+
+	// next scene not found
+	if (it == this->scenes.end())
+		return;
+	unique_ptr<Scene> & scene = *it;
+
+	// Delete all components of the current scene
+	ComponentManager & mgr = ComponentManager::get_instance();
+	mgr.delete_all_components();
+
+	// Load the new scene
+	scene->load_scene();
+}
+
diff --git a/src/crepe/api/SceneManager.h b/src/crepe/api/SceneManager.h
new file mode 100644
index 0000000..1e0e670
--- /dev/null
+++ b/src/crepe/api/SceneManager.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include <memory>
+#include <queue>
+#include <vector>
+
+#include "Scene.h"
+
+namespace crepe {
+
+class SceneManager {
+public:
+	// Singleton
+	static SceneManager & get_instance();
+	SceneManager(const SceneManager &) = delete;
+	SceneManager(SceneManager &&) = delete;
+	SceneManager & operator=(const SceneManager &) = delete;
+	SceneManager & operator=(SceneManager &&) = delete;
+
+public:
+	/**
+	 * \brief Add a new concrete scene to the scene manager
+	 *
+	 * \tparam T  Type of concrete scene
+	 * \param name  Name of new scene
+	 */
+	template <typename T>
+	void add_scene(const std::string & name);
+	/**
+	 * \brief Set the next scene
+	 *
+	 * This scene will be loaded at the end of the frame
+	 *
+	 * \param name  Name of the next scene
+	 */
+	void set_next_scene(const std::string & name);
+	//! Load a new scene (if there is one)
+	void load_next_scene();
+
+private:
+	SceneManager() = default;
+
+private:
+	std::vector<std::unique_ptr<Scene>> scenes;
+	std::string next_scene;
+};
+
+} // namespace crepe
+
+#include "SceneManager.hpp"
diff --git a/src/crepe/api/SceneManager.hpp b/src/crepe/api/SceneManager.hpp
new file mode 100644
index 0000000..8bad7b2
--- /dev/null
+++ b/src/crepe/api/SceneManager.hpp
@@ -0,0 +1,18 @@
+#include "SceneManager.h"
+
+namespace crepe {
+
+template <typename T>
+void SceneManager::add_scene(const std::string & name) {
+	static_assert(std::is_base_of<Scene, T>::value,
+				  "T must be derived from Scene");
+
+	scenes.emplace_back(make_unique<T>(name));
+
+	// The first scene added, is the one that will be loaded at the beginning
+	if (next_scene.empty()) {
+		next_scene = name;
+	}
+}
+
+} // namespace crepe
diff --git a/src/example/CMakeLists.txt b/src/example/CMakeLists.txt
index 81df8d1..023d0ad 100644
--- a/src/example/CMakeLists.txt
+++ b/src/example/CMakeLists.txt
@@ -25,3 +25,4 @@ add_example(asset_manager)
 add_example(particle)
 add_example(physics)
 add_example(ecs)
+add_example(scene_manager)
diff --git a/src/example/scene_manager.cpp b/src/example/scene_manager.cpp
new file mode 100644
index 0000000..bce42ca
--- /dev/null
+++ b/src/example/scene_manager.cpp
@@ -0,0 +1,75 @@
+#include <iostream>
+
+#include "../crepe/ComponentManager.h"
+#include "../crepe/api/GameObject.h"
+#include "../crepe/api/Metadata.h"
+#include "../crepe/api/Point.h"
+#include "../crepe/api/Scene.h"
+#include "../crepe/api/SceneManager.h"
+
+using namespace crepe;
+using namespace std;
+
+class concreteScene1 : public Scene {
+public:
+	concreteScene1(string name) : Scene(name) {}
+
+	void load_scene() {
+		GameObject object1(0, "scene_1", "tag_scene_1", Point{0, 0}, 0, 1);
+		GameObject object2(1, "scene_1", "tag_scene_1", Point{1, 0}, 0, 1);
+		GameObject object3(2, "scene_1", "tag_scene_1", Point{2, 0}, 0, 1);
+	}
+};
+
+class concreteScene2 : public Scene {
+public:
+	concreteScene2(string name) : Scene(name) {}
+
+	void load_scene() {
+		GameObject object1(0, "scene_2", "tag_scene_2", Point{0, 0}, 0, 1);
+		GameObject object2(1, "scene_2", "tag_scene_2", Point{0, 1}, 0, 1);
+		GameObject object3(2, "scene_2", "tag_scene_2", Point{0, 2}, 0, 1);
+		GameObject object4(3, "scene_2", "tag_scene_2", Point{0, 3}, 0, 1);
+	}
+};
+
+int main() {
+	SceneManager & scene_mgr = SceneManager::get_instance();
+
+	// Add the scenes to the scene manager
+	scene_mgr.add_scene<concreteScene1>("scene1");
+	scene_mgr.add_scene<concreteScene2>("scene2");
+
+	// There is no need to call set_next_scene() at the beginnen, because the first scene will be automatically set as the next scene
+	// Load scene1 (the first scene added)
+	scene_mgr.load_next_scene();
+
+	// Get the Metadata components of each GameObject of Scene1
+	ComponentManager & component_mgr = ComponentManager::get_instance();
+	vector<reference_wrapper<Metadata>> metadata
+		= component_mgr.get_components_by_type<Metadata>();
+
+	cout << "Metadata components of Scene1:" << endl;
+	// Print the Metadata
+	for (auto & m : metadata) {
+		cout << "Id: " << m.get().game_object_id << " Name: " << m.get().name
+			 << " Tag: " << m.get().tag << endl;
+	}
+
+	// Set scene2 as the next scene
+	scene_mgr.set_next_scene("scene2");
+	// Load scene2
+	scene_mgr.load_next_scene();
+
+	// Get the Metadata components of each GameObject of Scene2
+	metadata = component_mgr.get_components_by_type<Metadata>();
+
+	cout << "Metadata components of Scene2:" << endl;
+	// Print the Metadata
+	for (auto & m : metadata) {
+		cout << "Id: " << m.get().game_object_id << " Name: " << m.get().name
+			 << " Tag: " << m.get().tag << endl;
+	}
+
+	return 0;
+}