Use fewer pointers refactor: get rid of visible_world_ in drivenengine. The world is now fully owned by the drivenengine.

luprex/cpp/core/drivenengine.hpp

@@ -211,14 +211,6 @@ public:
     //
     void set_have_prints(bool b) { have_prints_ = b; }
 
-    // Set the world pointer and the actor ID.
-    //
-    // This allows the graphics engine to query the DrivenEngine
-    // about the state of the world and the player.  It is legal to set these
-    // to zero, in which case queries will return null results.
-    //
-    void set_visible_world_and_actor(World *w, int64_t actor);
-    
     // Stop the driver.  The engine should call this when it's done
     // and there's nothing left to do.
     //
@@ -287,21 +279,36 @@ private:
     // Get the channel associated with the specified channel ID.
     Channel *get_chid(int chid) const;
     
+protected:
+    // The DrivenEngine can optionally contain
+    // a world model.  This is initialized to
+    // nullptr, but classes that derive from
+    // DrivenEngine can store a world model here.
+    // If they do, then functions like get_near
+    // will reference this model.
+    // 
+    std::unique_ptr<World> world_;
+
+    // When the Driver calls get_actor_id,
+    // we return this value.  This is initialized
+    // to zero, but classes that derive from
+    // DrivenEngine can store an actor_id here.
+    //
+    int64_t actor_id_ = 0;
+
 private:
     SharedChannel channels_[DRV_MAX_CHAN];
-    int next_unused_chid_;
+    int next_unused_chid_ = 1;
     eng::vector<SharedChannel> accepted_channels_;
     eng::vector<uint32_t> new_outgoing_;
     eng::vector<uint32_t> listen_ports_;
-    World *visible_world_;
-    int64_t visible_actor_id_;
     util::IdVector scan_result_;
     std::vector<util::SharedStdString> anim_queues_;
     StreamBuffer call_function_retpk_;
-    bool rescan_lua_source_;
-    double clock_;
-    bool have_prints_;
-    bool stop_driver_;
+    bool rescan_lua_source_ = false;
+    double clock_ = 0.0;
+    bool have_prints_ = false;
+    bool stop_driver_ = false;
     friend class Channel;
 };