update

src/EcsWorld.cs

@@ -157,6 +157,8 @@ namespace DCFApixels.DragonECS
 
             int entitiesCapacity = ArrayUtility.NormalizeSizeToPowerOfTwo(config.EntitiesCapacity);
             _entityDispenser = new IdDispenser(entitiesCapacity, 0, OnEntityDispenserResized);
+
+            GetComponentTypeID<NullComponent>();
         }
         public void Destroy()
         {

src/Pools/EcsPool.cs

@@ -166,6 +166,21 @@ namespace DCFApixels.DragonECS
 #endif
             CopyComponent(ref Get(fromEntityID), ref toWorld.GetPool<T>().TryAddOrGet(toEntityID));
         }
+
+        public void ClearAll()
+        {
+            var span = _source.Where(out SingleAspect<EcsPool<T>> _);
+            _itemsCount = 0;
+            _recycledItemsCount = 0;
+            foreach (var entityID in span)
+            {
+                ref int itemIndex = ref _mapping[entityID];
+                DisableComponent(ref _items[itemIndex]);
+                itemIndex = 0;
+                _mediator.UnregisterComponent(entityID, _componentTypeID, _maskBit);
+                _listeners.InvokeOnDel(entityID);
+            }
+        }
         #endregion
 
         #region Callbacks
@@ -199,9 +214,15 @@ namespace DCFApixels.DragonECS
         #endregion
 
         #region Other
-        void IEcsPool.AddRaw(int entityID, object dataRaw) { Add(entityID) = (T)dataRaw; }
+        void IEcsPool.AddRaw(int entityID, object dataRaw)
+        {
+            Add(entityID) = dataRaw == null ? default : (T)dataRaw;
+        }
         object IEcsReadonlyPool.GetRaw(int entityID) { return Get(entityID); }
-        void IEcsPool.SetRaw(int entityID, object dataRaw) { Get(entityID) = (T)dataRaw; }
+        void IEcsPool.SetRaw(int entityID, object dataRaw)
+        {
+            Get(entityID) = dataRaw == null ? default : (T)dataRaw;
+        }
         #endregion
 
         #region Listeners

src/Pools/EcsPoolBase.cs

@@ -33,6 +33,7 @@ namespace DCFApixels.DragonECS
         void AddRaw(int entityID, object dataRaw);
         void SetRaw(int entityID, object dataRaw);
         void Del(int entityID);
+        void ClearAll();
         #endregion
     }
     /// <summary>A pool for struct components.</summary>
@@ -103,21 +104,68 @@ namespace DCFApixels.DragonECS
             public static readonly EcsNullPool instance = new EcsNullPool();
 
             #region Properties
-            int IEcsReadonlyPool.ComponentTypeID => -1;
+            int IEcsReadonlyPool.ComponentTypeID { get { return 0; } }//TODO Првоерить что NullComponent всегда имеет id 0 
-            Type IEcsReadonlyPool.ComponentType => typeof(NullComponent);
+            Type IEcsReadonlyPool.ComponentType { get { return typeof(NullComponent); } }
-            EcsWorld IEcsReadonlyPool.World => throw new NotImplementedException();
+            EcsWorld IEcsReadonlyPool.World
-            public int Count => -1;
+            {
+                get
+                {
+#if (DEBUG && !DISABLE_DEBUG)
+                    throw new NullInstanceException();
+#endif
+                }
+            }
+            public int Count { get { return 0; } }
             public bool IsReadOnly { get { return true; } }
             #endregion
 
             #region Methods
-            bool IEcsReadonlyPool.Has(int index) => false;
+            bool IEcsReadonlyPool.Has(int index)
-            void IEcsPool.Del(int entityID) => throw new NotImplementedException();
+            {
-            void IEcsPool.AddRaw(int entityID, object dataRaw) => throw new NotImplementedException();
+                return false;
-            object IEcsReadonlyPool.GetRaw(int entityID) => throw new NotImplementedException();
+            }
-            void IEcsPool.SetRaw(int entity, object dataRaw) => throw new NotImplementedException();
+            void IEcsPool.Del(int entityID)
-            void IEcsReadonlyPool.Copy(int fromEntityID, int toEntityID) => throw new NotImplementedException();
+            {
-            void IEcsReadonlyPool.Copy(int fromEntityID, EcsWorld toWorld, int toEntityID) => throw new NotImplementedException();
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            void IEcsPool.AddRaw(int entityID, object dataRaw)
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            object IEcsReadonlyPool.GetRaw(int entityID)
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            void IEcsPool.SetRaw(int entity, object dataRaw)
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            void IEcsReadonlyPool.Copy(int fromEntityID, int toEntityID)
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            void IEcsReadonlyPool.Copy(int fromEntityID, EcsWorld toWorld, int toEntityID)
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
+            void IEcsPool.ClearAll()
+            {
+#if (DEBUG && !DISABLE_DEBUG)
+                throw new NullInstanceException();
+#endif
+            }
             #endregion
 
             #region Callbacks

src/Pools/EcsTagPool.cs

@@ -145,6 +145,18 @@ namespace DCFApixels.DragonECS
                 Add(entityID);
             }
         }
+
+        public void ClearAll()
+        {
+            var span = _source.Where(out SingleAspect<EcsTagPool<T>> _);
+            _count = 0;
+            foreach (var entityID in span)
+            {
+                _mapping[entityID] = false;
+                _mediator.UnregisterComponent(entityID, _componentTypeID, _maskBit);
+                _listeners.InvokeOnDel(entityID);
+            }
+        }
         #endregion
 
         #region Callbacks

src/Utils/Exceptions.cs

@@ -11,6 +11,13 @@ namespace DCFApixels.DragonECS
         public EcsFrameworkException(string message, Exception inner) : base(EcsConsts.EXCEPTION_MESSAGE_PREFIX + message, inner) { }
     }
     [Serializable]
+    public class NullInstanceException : EcsFrameworkException
+    {
+        public NullInstanceException() { }
+        public NullInstanceException(string message) : base(EcsConsts.EXCEPTION_MESSAGE_PREFIX + message) { }
+        public NullInstanceException(string message, Exception inner) : base(EcsConsts.EXCEPTION_MESSAGE_PREFIX + message, inner) { }
+    }
+    [Serializable]
     public class EcsRunnerImplementationException : EcsFrameworkException
     {
         public EcsRunnerImplementationException() { }