1 files changed, 135 insertions, 0 deletions
diff --git a/mwe/ecs-homemade/inc/ComponentManager.hpp b/mwe/ecs-homemade/inc/ComponentManager.hpp
new file mode 100644
index 0000000..92db1d4
--- /dev/null
+++ b/mwe/ecs-homemade/inc/ComponentManager.hpp
@@ -0,0 +1,135 @@
+
+template <typename T, typename... Args>
+T & ComponentManager::AddComponent(std::uint32_t id, Args &&... args) {
+	//Determine the type of T (this is used as the key of the unordered_map<>)
+	std::type_index type = typeid(T);
+
+	//Check if this component type is already in the unordered_map<>
+	if (mComponents.find(type) == mComponents.end()) {
+		//If not, create a new (empty) vector<> of vector<unique_ptr<Component>>
+		mComponents[type]
+			= std::vector<std::vector<std::unique_ptr<Component>>>();
+	}
+
+	//Resize the vector<> if the id is greater than the current size
+	if (id >= mComponents[type].size()) {
+		//Initialize new slots to nullptr (resize does automatically init to nullptr)
+		mComponents[type].resize(id + 1);
+	}
+
+	//Create a new component of type T using perfect forwarding and store its unique_ptr in the vector<>
+	mComponents[type][id].push_back(
+		std::make_unique<T>(std::forward<Args>(args)...));
+
+	return static_cast<T &>(*mComponents[type][id].back().get());
+}
+
+template <typename T>
+void ComponentManager::DeleteComponentsById(std::uint32_t id) {
+	//Determine the type of T (this is used as the key of the unordered_map<>)
+	std::type_index type = typeid(T);
+
+	//Find the type (in the unordered_map<>)
+	if (mComponents.find(type) != mComponents.end()) {
+		//Get the correct vector<>
+		std::vector<std::vector<std::unique_ptr<Component>>> & componentArray
+			= mComponents[type];
+
+		//Make sure that the id (that we are looking for) is within the boundaries of the vector<>
+		if (id < componentArray.size()) {
+			//Clear the whole vector<> of this specific type and id
+			componentArray[id].clear();
+		}
+	}
+}
+
+template <typename T>
+void ComponentManager::DeleteComponents() {
+	//Determine the type of T (this is used as the key of the unordered_map<>)
+	std::type_index type = typeid(T);
+
+	//Find the type (in the unordered_map<>)
+	if (mComponents.find(type) != mComponents.end()) {
+		//Clear the whole vector<> of this specific type
+		mComponents[type].clear();
+	}
+}
+
+template <typename T>
+std::vector<std::reference_wrapper<T>>
+ComponentManager::GetComponentsByID(std::uint32_t id) const {
+	//Determine the type of T (this is used as the key of the unordered_map<>)
+	std::type_index type = typeid(T);
+
+	//Create an empty vector<>
+	std::vector<std::reference_wrapper<T>> componentVector;
+
+	//Find the type (in the unordered_map<>)
+	if (mComponents.find(type) != mComponents.end()) {
+
+		//Get the correct vector<>
+		const std::vector<std::vector<std::unique_ptr<Component>>> &
+			componentArray
+			= mComponents.at(type);
+
+		//Make sure that the id (that we are looking for) is within the boundaries of the vector<>
+		if (id < componentArray.size()) {
+			//Loop trough the whole vector<>
+			for (const std::unique_ptr<Component> & componentPtr :
+				 componentArray[id]) {
+				//Cast the unique_ptr to a raw pointer
+				T * castedComponent = static_cast<T *>(componentPtr.get());
+
+				//Ensure that the cast was successful
+				if (castedComponent) {
+					//Add the dereferenced raw pointer to the vector<>
+					componentVector.push_back(*castedComponent);
+				}
+			}
+		}
+	}
+
+	//Return the vector<>
+	return componentVector;
+}
+
+template <typename T>
+std::vector<std::reference_wrapper<T>>
+ComponentManager::GetComponentsByType() const {
+	//Determine the type of T (this is used as the key of the unordered_map<>)
+	std::type_index type = typeid(T);
+
+	//Create an empty vector<>
+	std::vector<std::reference_wrapper<T>> componentVector;
+	//std::uint32_t id = 0;	//Set the id to 0 (the id will also be stored in the returned vector<>)
+
+	//Find the type (in the unordered_map<>)
+	if (mComponents.find(type) != mComponents.end()) {
+
+		//Get the correct vector<>
+		const std::vector<std::vector<std::unique_ptr<Component>>> &
+			componentArray
+			= mComponents.at(type);
+
+		//Loop through the whole vector<>
+		for (const std::vector<std::unique_ptr<Component>> & component :
+			 componentArray) {
+			//Loop trough the whole vector<>
+			for (const std::unique_ptr<Component> & componentPtr : component) {
+				//Cast the unique_ptr to a raw pointer
+				T * castedComponent = static_cast<T *>(componentPtr.get());
+
+				//Ensure that the cast was successful
+				if (castedComponent) {
+					//Pair the dereferenced raw pointer and the id and add it to the vector<>
+					componentVector.emplace_back(std::ref(*castedComponent));
+				}
+			}
+
+			//++id;	//Increase the id (the id will also be stored in the returned vector<>)
+		}
+	}
+
+	//Return the vector<>
+	return componentVector;
+}