Spawner, SpawnPoint and PlayerSpawn components, and base work on their systems

include/Engine/Core/EntityWrapper.h

@@ -7,6 +7,11 @@
 class World;
 struct EntityWrapper
 {
+    EntityWrapper()
+        : World(nullptr)
+        , ID(EntityID_Invalid)
+    { }
+
     EntityWrapper(::World* world, EntityID id)
         : World(world)
         , ID(id)

include/Engine/Core/EventBroker.h

@@ -43,7 +43,7 @@ template <typename ContextType, typename EventType>
 class EventRelay : public BaseEventRelay
 {
 public:
-    typedef std::function<bool(const EventType&)> CallbackType;
+    typedef std::function<bool(EventType&)> CallbackType;
 
     EventRelay()
         : m_Callback(nullptr)
@@ -65,7 +65,7 @@ template <typename ContextType, typename EventType>
 bool EventRelay<ContextType, EventType>::Receive(const std::shared_ptr<Event> event)
 {
     if (m_Callback != nullptr) {
-        return m_Callback(*static_cast<const EventType*>(event.get()));
+        return m_Callback(*static_cast<EventType*>(event.get()));
     } else {
         return false;
     }

include/Engine/Core/World.h

@@ -34,6 +34,8 @@ public:
     EntityID GetParent(EntityID entity);
     // Change the parent of an entity
     void SetParent(EntityID entity, EntityID parent);
+    // Get children of an entity
+    const std::pair<std::unordered_multimap<EntityID, EntityID>::const_iterator, std::unordered_multimap<EntityID, EntityID>::const_iterator> GetChildren(EntityID entity);
     // Get all component pools
     const std::unordered_map<std::string, ComponentPool*>& GetComponentPools() const { return m_ComponentPools; }
     // Get the entity children map