Adapted Escape the Dawn engine.

src/System.h

@@ -0,0 +1,34 @@
+#ifndef System_h__
+#define System_h__
+
+#include "Factory.h"
+#include "Entity.h"
+#include "Component.h"
+
+class World;
+
+class System
+{
+public:
+	System(World* world) : m_World(world) { }
+	virtual ~System() { }
+
+	virtual void Initialize() { }
+
+	// Called once per system every tick
+	virtual void Update(double dt) { }
+	// Called once for every entity in the world every tick
+	virtual void UpdateEntity(double dt, EntityID entity, EntityID parent) { }
+
+	// Called when a component is created
+	virtual void OnComponentCreated(std::string type, std::shared_ptr<Component> component) { }
+	// Called when a component is removed
+	virtual void OnComponentRemoved(std::string type, Component* component) { }
+
+protected:
+	World* m_World;
+};
+
+class SystemFactory : public Factory<System*> { };
+
+#endif // System_h__