Cleanup

include/Engine/Entity/Entity.h

@@ -2,7 +2,11 @@
 #include <J3ML/LinearAlgebra/Vector2.hpp>
 #include <vector>
 
-class Entity {
+namespace Engine {
+    class Entity;
+}
+
+class Engine::Entity {
 protected:
     std::vector<Entity*> children{};
     Vector2 position = {0, 0};