-git now should ignore .dub/dub.json

-added onAdd/onRemove to test
-added onAdd/onRemove callbacks for system
-generating onAdd/onRemove listeners

.gitignore

@@ -3,5 +3,5 @@
 !source/**
 !tests/**
 !README.md
-!dub.json
+!./dub.json
 !.gitignore

source/ecs/manager.d

@@ -84,6 +84,12 @@ class EntityManager
         assert(register_state, "beginRegister() should be called before endRegister();");
         register_state = false;
 
+        foreach(ref info; &entities_infos.byValue)
+        {
+            if(info.systems)Mallocator.instance.dispose(info.systems);
+            info.systems = Mallocator.instance.makeArray!bool(systems.length);
+        }
+
         foreach (ref system; systems)
         {
             if (system.m_update is null)
@@ -151,6 +157,11 @@ class EntityManager
             }
         }
 
+        foreach(info; &entities_infos.byValue)
+        {
+            generateListeners(info);
+        }
+
         generateDependencies();
     }
 
@@ -681,7 +692,6 @@ class EntityManager
                 static "~RetType.stringof~" call" ~ func
                 ~ "(void* system_pointer)
                 {
-
                     Sys* s = cast(Sys*) system_pointer;
                     "~ret_str~"s." ~ func ~ "();
                 }
@@ -693,6 +703,32 @@ class EntityManager
             //dfmt on
         }
 
+        static string catchEntityFunc(RetType = void)(string member, string func)
+        {
+            //dfmt off
+
+            static if(is(RetType == void))string ret_str = "";
+            else string ret_str = "return ";
+            string ret = "static if (hasMember!(Sys, \"" ~ func ~ "\") && 
+                            Parameters!(Sys."~func~").length == 1 && 
+                            is(Parameters!(Sys."~func~")[0] == Sys.EntitiesData) &&
+                            is(ReturnType!(Sys."~func~") == "~RetType.stringof~"))
+            {
+                static "~RetType.stringof~" call" ~ func
+                ~ "(void* system_pointer)
+                {
+                    Sys* s = cast(Sys*) system_pointer;
+                    Sys.EntitiesData data;
+                    "~ret_str~"s." ~ func ~ "(data);
+                }
+
+                system."
+                ~ member ~ " = &call" ~ func ~ ";
+            }";
+            return ret;
+            //dfmt on
+        }
+
         mixin(catchFunc("m_enable", "onEnable"));
         mixin(catchFunc("m_disable", "onDisable"));
         mixin(catchFunc("m_create", "onCreate"));
@@ -700,6 +736,9 @@ class EntityManager
         mixin(catchFunc!(bool)("m_begin", "onBegin"));
         mixin(catchFunc("m_end", "onEnd"));
 
+        mixin(catchEntityFunc("m_entity_added","onAdd"));
+        mixin(catchEntityFunc("m_entity_removed","onRemove"));
+
         system.m_system_pointer = cast(void*) Mallocator.instance.make!Sys;
         system.m_priority = priority;
         (cast(Sys*) system.m_system_pointer).__ecsInitialize();
@@ -1145,6 +1184,8 @@ class EntityManager
                 current_delta += entites_in_block * components[id].size;
             }
 
+            info.systems = Mallocator.instance.makeArray!bool(systems.length);
+
             foreach (i, ref system; systems)
             {
                 if (system.m_update is null)
@@ -1153,10 +1194,52 @@ class EntityManager
             }
 
             entities_infos.add(info.components, info);
+
+            generateListeners(info);
         }
         return info;
     }
 
+    void generateListeners(EntityInfo* info)
+    {
+        if(info.add_listeners)
+        {
+            Mallocator.instance.dispose(info.add_listeners);
+            info.add_listeners = null;
+        }
+        if(info.remove_listeners)
+        {
+            Mallocator.instance.dispose(info.remove_listeners);
+            info.remove_listeners = null;
+        }
+
+        ushort[] tmp_add = (cast(ushort*)alloca(systems.length*ushort.sizeof))[0..systems.length];
+        ushort[] tmp_rem = (cast(ushort*)alloca(systems.length*ushort.sizeof))[0..systems.length];
+        int add_len = 0;
+        int rem_len = 0;
+        foreach(i;0..systems.length)
+        {
+            if(info.systems[i])
+            {
+                System* system = &systems[i];
+                if(system.m_entity_added)tmp_add[add_len++] = cast(ushort)i;
+                if(system.m_entity_removed)tmp_rem[rem_len++] = cast(ushort)i;
+            }
+        }
+        
+        if(add_len)
+        {
+            info.add_listeners = Mallocator.instance.makeArray!ushort(add_len);
+            memcpy(info.add_listeners.ptr,tmp_add.ptr,add_len*ushort.sizeof);
+        }
+
+        if(rem_len)
+        {
+            info.remove_listeners = Mallocator.instance.makeArray!ushort(rem_len);
+            memcpy(info.remove_listeners.ptr,tmp_add.ptr,rem_len*ushort.sizeof);
+        }
+    }
+
     export void addSystemCaller(ref EntityInfo entity, uint system_id) nothrow @nogc
     {
         System* system = &systems[system_id];
@@ -1193,6 +1276,8 @@ class EntityManager
 
         if (index < passes[system.m_pass].system_callers.length)
             passes[system.m_pass].system_callers[index].infos.add(&entity);
+
+        entity.systems[system_id] = true;
     }
 
     /************************************************************************************************************************
@@ -2084,6 +2169,13 @@ class EntityManager
         ///max number of entities in block
         ushort max_entities;
 
+        ///array of systems which will update this entity
+        bool[] systems;
+        ///systems which are listening for added entities
+        ushort[] add_listeners;
+        ///systems which are listening for removed entities
+        ushort[] remove_listeners;
+
         ///pointer to first block/page
         EntitiesBlock* first_block;
         ///pointer to last block

source/ecs/system.d

@@ -9,12 +9,15 @@ import ecs.manager;
 /************************************************************************************************************************
 *System contain data required to proper glue EntityManager with Systems.
 *System callbacks:
+*<br/>-void update(EntitesData);
 *<br/>-void onEnable()
 *<br/>-void onDisable();
 *<br/>-bool onBegin();
 *<br/>-void onEnd();
 *<br/>-void onCreate()
 *<br/>-void onDestroy();
+*<br/>-void onAdd(EntitesData);
+*<br/>-void onRemove(EntitiesData);
 */
 struct System
 {
@@ -132,6 +135,9 @@ package:
     void* m_begin;
     void* m_end;
 
+    void* m_entity_added;
+    void* m_entity_removed;
+
     //void function(ref EntityManager.CallData data) m_initialize;
     //void function(ref EntityManager.CallData data) m_deinitilize;
     void* m_initialize; 

tests/tests.d

@@ -108,6 +108,21 @@ struct TestSystem
 		writeln("On Test System destroy.");
 	}
 
+	void onAdd(EntitiesData data)
+	{
+		writeln("Entity added ID: ",data.entites[0].id);
+	}
+
+	/*void onAdd()
+	{
+
+	}*/
+
+	void onRemove(EntitiesData data)
+	{
+		writeln("Entity destroyed ID: ",data.entites[0].id);
+	}
+
 	bool onBegin()
 	{
 		//writeln("On Test System begin.");
@@ -127,6 +142,7 @@ struct TestSystem
 	static struct EntitiesData
 	{
 		size_t length;
+		const(Entity)[] entites;
 		TestComp[] test;
 		TestComp2[] test2;
 		@readonly @optional const(TestComp3)[] test3;