-getComponent functions for Template and Entity

-error information about adding system with non existing component (prints name of system and component)
-fill components in template with default values

source/ecs/entity.d

@@ -16,10 +16,22 @@ struct Entity
     {
         EntityManager.instance.id_manager.update(this);
     }
+
+    T* getComponent(T)()
+    {
+        EntityManager.EntitiesBlock* block = gEM.getMetaData(&this);
+        EntityManager.EntityInfo* info = block.type_data;
+        return cast(T*)(cast(void*)&this + info.deltas[T.component_id]);
+    }
 }
 
 struct EntityTemplate
 {
     ubyte[] entity_data;
     EntityManager.EntityInfo* info;
+
+    T* getComponent(T)()
+    {
+        return cast(T*)(entity_data.ptr + info.deltas[T.component_id]);
+    }
 }

source/ecs/manager.d

@@ -51,11 +51,15 @@ class EntityManager
 
         static string genCompList()()
         {
-            string ret;
+            string ret = "uint comp;";
             foreach (i; 1 .. (Parameters!(Sys.update)).length)
             {
-                ret ~= "system.m_components[" ~ (i - 1)
+                ret ~= "comp = components_map.get(types[" ~ i.to!string ~ "].stringof, ushort.max);\n
-                    .to!string ~ "] = components_map.get(types[" ~ i.to!string ~ "].stringof);\n";
+                    if(comp == ushort.max)assert(0,\"Can't register system \\\"" ~ Sys.stringof
+                    ~ "\\\" due to non existing component \\\"\"~types[" ~ i.to!string ~ "].stringof~\"\\\".\");
+                    system.m_components[" ~ (i - 1)
+                    .to!string ~ "] = comp;";
+
             }
             return ret;
         }
@@ -131,10 +135,11 @@ class EntityManager
             static assert(0, "Component should have \"__gshared ushort component_id");
         }
 
-        ushort size = Comp.sizeof;
         ComponentInfo info;
-        info.size = size;
+        info.size = Comp.sizeof;
         info.aligment = Comp.alignof; //8;
+        info.init_data = Mallocator.instance.makeArray!ubyte(Comp.sizeof);
+        *cast(Comp*)info.init_data.ptr = Comp();
 
         components.add(info);
         Comp.component_id = cast(ushort)(components.length - 1);
@@ -196,6 +201,13 @@ class EntityManager
         EntityTemplate* temp = Mallocator.instance.make!EntityTemplate;
         temp.entity_data = Mallocator.instance.makeArray!ubyte(info.size);
         temp.info = info;
+
+        //fill components with default data
+        foreach(comp;info.components)
+        {
+            temp.entity_data[info.deltas[comp]..info.deltas[comp]+components[comp].size] = components[comp].init_data;
+        }
+
         return temp;
     }
 
@@ -475,6 +487,7 @@ class EntityManager
     {
         ushort size;
         ushort aligment;
+        ubyte[] init_data;
     }
 
     /************************************************************************************************************************