12 files changed, 352 insertions, 0 deletions
diff --git a/mwe/ecs-memory-efficient/CMakeLists.txt b/mwe/ecs-memory-efficient/CMakeLists.txt
new file mode 100644
index 0000000..d072907
--- /dev/null
+++ b/mwe/ecs-memory-efficient/CMakeLists.txt
@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.5)
+project(ecs-memory-efficient)
+
+# Set the C++ standard (optional, but good practice)
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED True)
+
+# Use the debug mode (otherwise breakpoints are not compiled)
+set(CMAKE_BUILD_TYPE Debug)
+
+add_executable(ecs-memory-efficient
+	src/main.cpp
+	src/ComponentManager.cpp
+	src/Components.cpp
+	src/GameObjectMax.cpp
+)
+target_include_directories(ecs-memory-efficient PRIVATE "${CMAKE_SOURCE_DIR}/inc")
diff --git a/mwe/ecs-memory-efficient/inc/ComponentManager.h b/mwe/ecs-memory-efficient/inc/ComponentManager.h
new file mode 100644
index 0000000..066795a
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/ComponentManager.h
@@ -0,0 +1,36 @@
+#pragma once
+
+#include "Components.h"
+#include "ContiguousContainer.h"
+
+class ComponentManager {
+public:
+	static ComponentManager& GetInstance();	//Singleton
+
+	ComponentManager(const ComponentManager&) = delete;	//Singleton
+    ComponentManager(ComponentManager&&) = delete;	//Singleton
+    ComponentManager& operator=(const ComponentManager&) = delete;	//Singleton
+    ComponentManager& operator=(ComponentManager&&) = delete;	//Singleton
+
+	template<typename... Args>
+    void addSpriteComponent(Args&&... args);
+	template<typename... Args>
+    void addRigidbodyComponent(Args&&... args);
+	template<typename... Args>
+    void addColiderComponent(Args&&... args);
+
+	std::vector<std::reference_wrapper<Sprite>> getAllSpriteReferences();
+	std::vector<std::reference_wrapper<Rigidbody>> getAllRigidbodyReferences();
+	std::vector<std::reference_wrapper<Colider>> getAllColiderReferences();
+
+private:
+    static ComponentManager mInstance;	//Singleton
+
+    ComponentManager();	//Singleton
+
+	ContiguousContainer<Sprite> mSpriteContainer;
+	ContiguousContainer<Rigidbody> mRigidbodyContainer;
+	ContiguousContainer<Colider> mColiderContainer;
+};
+
+#include "ComponentManager.hpp"
diff --git a/mwe/ecs-memory-efficient/inc/ComponentManager.hpp b/mwe/ecs-memory-efficient/inc/ComponentManager.hpp
new file mode 100644
index 0000000..1607c0c
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/ComponentManager.hpp
@@ -0,0 +1,15 @@
+	
+template<typename... Args>
+void ComponentManager::addSpriteComponent(Args&&... args) {
+	mSpriteContainer.pushBack(std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+void ComponentManager::addRigidbodyComponent(Args&&... args) {
+	mRigidbodyContainer.pushBack(std::forward<Args>(args)...);
+}
+
+template<typename... Args>
+void ComponentManager::addColiderComponent(Args&&... args){
+	mColiderContainer.pushBack(std::forward<Args>(args)...);
+}
diff --git a/mwe/ecs-memory-efficient/inc/Components.h b/mwe/ecs-memory-efficient/inc/Components.h
new file mode 100644
index 0000000..98c5fe7
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/Components.h
@@ -0,0 +1,33 @@
+#pragma once
+
+#include <string>
+
+class Component {
+public:
+	Component();
+
+	bool mActive;
+};
+
+class Sprite : public Component {
+public:
+	Sprite(std::string path);
+
+	std::string mPath;
+};
+
+class Rigidbody : public Component {
+public:
+	Rigidbody(int mass, int gravityScale, int bodyType);
+
+	int mMass;
+	int mGravityScale;
+	int mBodyType;
+};
+
+class Colider : public Component {
+public:
+	Colider(int size);
+
+	int mSize;
+};
diff --git a/mwe/ecs-memory-efficient/inc/ContiguousContainer.h b/mwe/ecs-memory-efficient/inc/ContiguousContainer.h
new file mode 100644
index 0000000..dd0321e
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/ContiguousContainer.h
@@ -0,0 +1,34 @@
+#pragma once
+
+#include <cstdlib>   // For malloc and free
+#include <new>       // For placement new
+#include <utility>   // For std::move and std::forward
+#include <stdexcept> // For std::bad_alloc
+#include <vector>    // For returning references
+
+template<typename T>
+class ContiguousContainer {
+public:
+    ContiguousContainer();
+    ~ContiguousContainer();
+
+    // Use perfect forwarding for pushBack
+    template<typename... Args>
+    void pushBack(Args&&... args);
+    
+    void popBack();
+    T& operator[](size_t index);
+    size_t getSize() const;
+
+	// Function to return references to all stored objects
+    std::vector<std::reference_wrapper<T>> getAllReferences();
+
+private:
+    T* mData;
+    size_t mSize;
+    size_t mCapacity;
+
+    void resize(size_t new_capacity);  // Resize function to allocate more space
+};
+
+#include "ContiguousContainer.hpp"
diff --git a/mwe/ecs-memory-efficient/inc/ContiguousContainer.hpp b/mwe/ecs-memory-efficient/inc/ContiguousContainer.hpp
new file mode 100644
index 0000000..878a85f
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/ContiguousContainer.hpp
@@ -0,0 +1,84 @@
+template<typename T>
+ContiguousContainer<T>::ContiguousContainer()
+    : mSize(0), mCapacity(10) {
+    // Allocate memory for 10 objects initially
+    mData = static_cast<T*>(malloc(mCapacity * sizeof(T)));
+    if (!mData) {
+        throw std::bad_alloc();
+    }
+}
+
+template<typename T>
+ContiguousContainer<T>::~ContiguousContainer() {
+    // Destroy all constructed objects
+    for (size_t i = 0; i < mSize; ++i) {
+        mData[i].~T();
+    }
+    // Free the allocated memory
+    free(mData);
+}
+
+template<typename T>
+template<typename... Args>
+void ContiguousContainer<T>::pushBack(Args&&... args) {
+    if (mSize == mCapacity) {
+        // Double the capacity if the container is full
+        resize(mCapacity * 2);
+    }
+    // Use placement new with perfect forwarding to construct the object in place
+    new (mData + mSize) T(std::forward<Args>(args)...);
+    ++mSize;
+}
+
+template<typename T>
+void ContiguousContainer<T>::popBack() {
+    if (mSize > 0) {
+        --mSize;
+        // Explicitly call the destructor
+        mData[mSize].~T();
+    }
+}
+
+template<typename T>
+T& ContiguousContainer<T>::operator[](size_t index) {
+    if (index >= mSize) {
+        throw std::out_of_range("Index out of range");
+    }
+    return mData[index];
+}
+
+template<typename T>
+size_t ContiguousContainer<T>::getSize() const {
+    return mSize;
+}
+
+// Function that returns a vector of references to all stored objects
+template<typename T>
+std::vector<std::reference_wrapper<T>> ContiguousContainer<T>::getAllReferences() {
+    std::vector<std::reference_wrapper<T>> references;
+    references.reserve(mSize);  // Reserve space to avoid reallocation
+    for (size_t i = 0; i < mSize; ++i) {
+        references.push_back(std::ref(mData[i]));
+    }
+    return references;
+}
+
+template<typename T>
+void ContiguousContainer<T>::resize(size_t new_capacity) {
+    // Allocate new memory block with the updated capacity
+    T* new_data = static_cast<T*>(malloc(new_capacity * sizeof(T)));
+    if (!new_data) {
+        throw std::bad_alloc();
+    }
+
+    // Move or copy existing objects to the new memory block
+    for (size_t i = 0; i < mSize; ++i) {
+        new (new_data + i) T(std::move(mData[i])); // Move the objects
+        mData[i].~T(); // Call the destructor for the old object
+    }
+
+    // Free the old memory block
+    free(mData);
+    mData = new_data;
+    mCapacity = new_capacity;
+}
diff --git a/mwe/ecs-memory-efficient/inc/GameObjectMax.h b/mwe/ecs-memory-efficient/inc/GameObjectMax.h
new file mode 100644
index 0000000..62cd3e6
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/GameObjectMax.h
@@ -0,0 +1,24 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+
+class GameObject {
+public:
+	GameObject(std::uint32_t id, std::string name, std::string tag, int layer);
+
+	template<typename... Args>
+    void addSpriteComponent(Args&&... args);
+	template<typename... Args>
+    void addRigidbodyComponent(Args&&... args);
+	template<typename... Args>
+    void addColiderComponent(Args&&... args);
+
+	std::uint32_t mId;
+	std::string mName;
+	std::string mTag;
+	bool mActive;
+	int mLayer;
+};
+
+#include "GameObjectMax.hpp"
diff --git a/mwe/ecs-memory-efficient/inc/GameObjectMax.hpp b/mwe/ecs-memory-efficient/inc/GameObjectMax.hpp
new file mode 100644
index 0000000..aac9811
--- /dev/null
+++ b/mwe/ecs-memory-efficient/inc/GameObjectMax.hpp
@@ -0,0 +1,16 @@
+#include "ComponentManager.h"
+
+template <typename... Args>
+void GameObject::addSpriteComponent(Args&&... args) {
+	ComponentManager::GetInstance().addSpriteComponent(std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+void GameObject::addRigidbodyComponent(Args&&... args) {
+	ComponentManager::GetInstance().addRigidbodyComponent(std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+void GameObject::addColiderComponent(Args&&... args) {
+	ComponentManager::GetInstance().addColiderComponent(std::forward<Args>(args)...);
+}
diff --git a/mwe/ecs-memory-efficient/src/ComponentManager.cpp b/mwe/ecs-memory-efficient/src/ComponentManager.cpp
new file mode 100644
index 0000000..20d0ce0
--- /dev/null
+++ b/mwe/ecs-memory-efficient/src/ComponentManager.cpp
@@ -0,0 +1,21 @@
+#include "ComponentManager.h"
+
+ComponentManager ComponentManager::mInstance;
+
+ComponentManager& ComponentManager::GetInstance() {
+	return mInstance;
+}
+
+ComponentManager::ComponentManager() {}
+
+std::vector<std::reference_wrapper<Sprite>> ComponentManager::getAllSpriteReferences() {
+	return mSpriteContainer.getAllReferences();
+}
+
+std::vector<std::reference_wrapper<Rigidbody>> ComponentManager::getAllRigidbodyReferences() {
+	return mRigidbodyContainer.getAllReferences();
+}
+
+std::vector<std::reference_wrapper<Colider>> ComponentManager::getAllColiderReferences() {
+	return mColiderContainer.getAllReferences();
+}
diff --git a/mwe/ecs-memory-efficient/src/Components.cpp b/mwe/ecs-memory-efficient/src/Components.cpp
new file mode 100644
index 0000000..c8347b3
--- /dev/null
+++ b/mwe/ecs-memory-efficient/src/Components.cpp
@@ -0,0 +1,11 @@
+#include "Components.h"
+#include <iostream>
+
+Component::Component() : mActive(true) {}
+
+Sprite::Sprite(std::string path) : mPath(path) {}
+
+Rigidbody::Rigidbody(int mass, int gravityScale, int bodyType)
+	: mMass(mass), mGravityScale(gravityScale), mBodyType(bodyType) {}
+
+Colider::Colider(int size) : mSize(size) {}
diff --git a/mwe/ecs-memory-efficient/src/GameObjectMax.cpp b/mwe/ecs-memory-efficient/src/GameObjectMax.cpp
new file mode 100644
index 0000000..b0c5af7
--- /dev/null
+++ b/mwe/ecs-memory-efficient/src/GameObjectMax.cpp
@@ -0,0 +1,7 @@
+#include "GameObjectMax.h"
+
+#include "ComponentManager.h"
+
+GameObject::GameObject(std::uint32_t id, std::string name, std::string tag,
+					   int layer)
+	: mId(id), mName(name), mTag(tag), mActive(true), mLayer(layer) {}
diff --git a/mwe/ecs-memory-efficient/src/main.cpp b/mwe/ecs-memory-efficient/src/main.cpp
new file mode 100644
index 0000000..c25816b
--- /dev/null
+++ b/mwe/ecs-memory-efficient/src/main.cpp
@@ -0,0 +1,54 @@
+#include <iostream>
+#include <vector>
+#include <cstdint>
+#include <chrono>
+
+#include "ComponentManager.h"
+#include "GameObjectMax.h"
+#include "Components.h"
+
+int main() {
+	auto startAdding = std::chrono::high_resolution_clock::now();
+
+	GameObject* gameObject[100000];
+
+	for(int i = 0; i < 100000; ++i) {
+		gameObject[i] = new GameObject(i, "Name", "Tag", 0);
+
+		gameObject[i]->addSpriteComponent("C:/Test");
+		gameObject[i]->addRigidbodyComponent(0, 0, i);
+		gameObject[i]->addColiderComponent(i);
+	}
+
+	auto stopAdding = std::chrono::high_resolution_clock::now();
+
+	//This is what systems would do:
+
+	std::vector<std::reference_wrapper<Sprite>> allSprites = ComponentManager::GetInstance().getAllSpriteReferences();
+	for(Sprite& sprite : allSprites) {
+		//std::cout << sprite.mPath << std::endl;
+	}
+	//std::cout << std::endl;
+
+	std::vector<std::reference_wrapper<Rigidbody>> allRigidbody = ComponentManager::GetInstance().getAllRigidbodyReferences();
+	for(Rigidbody& rigidbody : allRigidbody) {
+		//std::cout << rigidbody.mMass << " " << rigidbody.mGravityScale << " " << rigidbody.mBodyType << std::endl;
+	}
+	//std::cout << std::endl;
+
+	std::vector<std::reference_wrapper<Colider>> allColider = ComponentManager::GetInstance().getAllColiderReferences();
+	for(Colider& colider : allColider) {
+		//std::cout << colider.mSize << std::endl;
+	}
+
+	auto stopLooping = std::chrono::high_resolution_clock::now();
+
+	for (int i = 0; i < 100000; ++i) {
+    	delete gameObject[i];
+	}
+
+	auto Addtime = std::chrono::duration_cast<std::chrono::microseconds>(stopAdding - startAdding);
+	auto LoopTime = std::chrono::duration_cast<std::chrono::microseconds>(stopLooping - stopAdding);
+	std::cout << "AddTime: " << Addtime.count() << " us" << std::endl;
+	std::cout << "LoopTime: " << LoopTime.count() << " us" << std::endl;
+}