Engine directory for ticket #1

Engine/source/scene/sceneTracker.h

@@ -0,0 +1,163 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _SCENETRACKER_H_
+#define _SCENETRACKER_H_
+
+#ifndef _SCENEOBJECT_H_
+   #include "scene/sceneObject.h"
+#endif
+
+
+/// @file
+/// This file contains an abstract framework for tracking SceneObjects.
+
+
+class SceneTracker;
+
+
+//-----------------------------------------------------------------------------
+//    SceneObjectLink.
+//-----------------------------------------------------------------------------
+
+
+/// A SceneObjectLink represents the link between a SceneObject and a SceneTracker.
+class SceneObjectLink
+{
+   public:
+   
+      typedef void Parent;
+      friend class SceneTracker; // Administers our link fields.
+
+   protected:
+   
+      /// SceneObject being linked to; always set and never changes.
+      SceneObject* mObject;
+      
+      /// The scene tracker to which this link belongs.
+      SceneTracker* mTracker;
+            
+      /// Next scope link on this SceneObject; NULL if last.
+      SceneObjectLink* mNextLink;
+      
+      /// Previous scope link on this SceneObject; NULL if first.
+      SceneObjectLink* mPrevLink;
+
+   public:
+   
+      ///
+      SceneObjectLink( SceneTracker* tracker, SceneObject* object );
+      
+      virtual ~SceneObjectLink();
+
+      /// @return The SceneScopeTracker managing this link.
+      SceneTracker* getTracker() const { return mTracker; }
+
+      /// @return The object being linked to.
+      SceneObject* getObject() const { return mObject; }
+      
+      /// @return The next link in this link chain.
+      SceneObjectLink* getNextLink() const { return mNextLink; }
+      
+      /// @return The previous link in this link chain.
+      SceneObjectLink* getPrevLink() const { return mPrevLink; }
+
+      /// Notify the associated tracker that the transform state of the
+      /// scene object represented by this link has changed.
+      void update();
+
+      ///
+      static SceneObjectLink* getLinkForTracker( SceneTracker* tracker, SceneObject* fromObject );
+};
+
+
+//-----------------------------------------------------------------------------
+//    SceneTracker.
+//-----------------------------------------------------------------------------
+
+
+/// A SceneTracker tracks SceneObjects.
+///
+/// This is an abstract base class.
+class SceneTracker
+{
+   public:
+   
+      typedef void Parent;
+      friend class SceneObjectLink; // SceneObjectLink::update() notifies us on SceneObject state changes.
+
+   protected:
+   
+      /// If true, only client SceneObjects will be tracked; otherwise it's only server SceneObjects.
+      bool mIsClientTracker;
+      
+      /// Type mask that SceneObjects must match in order to be allowed to register.
+      U32 mObjectTypeMask;
+      
+      /// Return true if the given object qualifies for being managed by this SceneTracker.
+      virtual bool _isTrackableObject( SceneObject* object ) const
+      {
+         return ( object->isClientObject() == mIsClientTracker
+                  && ( object->getTypeMask() & getObjectTypeMask() ) );
+      }
+
+      /// Callback used for the initial scan of objects in init().
+      static void _containerFindCallback( SceneObject* object, SceneTracker* tracker );
+
+   public:
+   
+      ///
+      SceneTracker( bool isClientTracker, U32 typeMask = 0xFFFFFFFF );
+      
+      virtual ~SceneTracker();
+      
+      /// Initialize the tracker from the current scene.
+      virtual void init();
+
+      /// @return The type mask that must be matched by objects in order to be allowed to register.
+      U32 getObjectTypeMask() const { return mObjectTypeMask; }
+      
+      /// Set the type mask that objects must match in order to be allowed to register.
+      void setObjectTypeMask( U32 typeMask ) { mObjectTypeMask = typeMask; }
+
+      /// @return True if this tracker only deals with client objects; false if only server objects.
+      bool isClientTracker() const { return mIsClientTracker; }
+
+      /// Register a SceneObject for being tracked by this tracker.
+      ///
+      /// Only objects that fit the tracker's client/server state and
+      /// object type mask will actually get registered.  For other objects,
+      /// this is a NOP.
+      ///
+      /// @param object Scene object.
+      virtual void registerObject( SceneObject* object ) = 0;
+
+      /// Unregister the given object from the tracker.
+      /// @param object Scene object.
+      virtual void unregisterObject( SceneObject* object ) = 0;
+
+      /// Notify the tracker that the transform state of the given scene object has changed.
+      /// @param object Scene object.
+      virtual void updateObject( SceneObjectLink* object ) = 0;
+};
+
+#endif // !_SCENETRACKER_H_