Add ExecuteOnEntities (careful this may change with c# 7 in future)

Svelto.ECS/EntitiesDB.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Security.Principal;
 using Svelto.DataStructures;
 using Svelto.Utilities;
 
@@ -101,6 +102,42 @@ namespace Svelto.ECS.Internal
                 casted.ExecuteOnEntityView(entityGID.entityID, action);
         }
 
+        public void ExecuteOnEntities<T>(int groupID, ActionRef<T> action) where T : IEntityStruct
+        {
+            int count;
+            var entities = QueryEntities<T>(groupID, out count);
+
+            for (int i = 0; i < count; i++)
+                action(ref entities[i]);
+        }
+
+        public void ExecuteOnEntities<T>(ActionRef<T> action) where T : IEntityStruct
+        {
+            int count;
+            var entities = QueryEntities<T>(out count);
+
+            for (int i = 0; i < count; i++)
+                action(ref entities[i]);
+        }
+
+        public void ExecuteOnEntities<T, W>(int groupID, ref W value, ActionRef<T, W> action) where T : IEntityStruct
+        {
+            int count;
+            var entities = QueryEntities<T>(out count);
+
+            for (int i = 0; i < count; i++)
+                action(ref entities[i], ref value);
+        }
+
+        public void ExecuteOnEntities<T, W>(ref W value, ActionRef<T, W> action) where T : IEntityStruct
+        {
+            int count;
+            var entities = QueryEntities<T>(out count);
+
+            for (int i = 0; i < count; i++)
+                action(ref entities[i], ref value);
+        }
+
         public bool Exists<T>(EGID entityGID) where T : IEntityStruct
         {
             TypeSafeDictionary<T> casted;

Svelto.ECS/IEntitiesDB.cs

@@ -39,6 +39,12 @@ namespace Svelto.ECS
         void ExecuteOnEntity<T, W>(EGID egid, ref W value, ActionRef<T, W> action) where T : IEntityStruct;
         void ExecuteOnEntity<T>(EGID egid, ActionRef<T> action) where T : IEntityStruct;
         
+        void ExecuteOnEntities<T>(int groupID, ActionRef<T> action) where T : IEntityStruct;
+        void ExecuteOnEntities<T>(ActionRef<T> action) where T : IEntityStruct;
+        
+        void ExecuteOnEntities<T, W>(int groupID, ref W value, ActionRef<T, W> action) where T : IEntityStruct;
+        void ExecuteOnEntities<T, W>(ref W value, ActionRef<T, W> action) where T : IEntityStruct;
+        
         bool Exists<T>(EGID egid) where T : IEntityStruct;
         
         bool HasAny<T>() where T:IEntityStruct;