Merge branch 'max/POC-ECS-memory-efficient' of github.com:lonkaars/crepe

1 files changed, 84 insertions, 0 deletions

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;
+}