+typedef struct ent_region ent_region;
+typedef struct ent_list ent_list;
+typedef struct ent_glider ent_glider;
+typedef struct ent_npc ent_npc;
+
+typedef struct ent_call ent_call;
+struct ent_call{
+ u32 id;
+ i32 function;
+ void *data;
+};
+
+typedef enum entity_call_result entity_call_result;
+enum entity_call_result
+{
+ k_entity_call_result_OK,
+ k_entity_call_result_unhandled,
+ k_entity_call_result_invalid
+};
+
+typedef enum entity_call_result
+ (*fn_entity_call_handler)( world_instance *, ent_call *);
+