Moved DatabasePager into from osgProducer into osgDB. This means that osgDB

is now dependant on OpenThreads.

include/osgDB/DatabasePager

@@ -0,0 +1,144 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield 
+ *
+ * This library is open source and may be redistributed and/or modified under  
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * OpenSceneGraph Public License for more details.
+*/
+
+#ifndef OSGDB_DATABASEPAGER
+#define OSGDB_DATABASEPAGER 1
+
+#include <osg/NodeVisitor>
+#include <osg/Group>
+#include <osg/PagedLOD>
+#include <osg/Drawable>
+
+#include <OpenThreads/Thread>
+#include <OpenThreads/Mutex>
+
+#include <osgDB/Export>
+
+#include <map>
+#include <set>
+
+namespace osgDB {
+
+/** Database paging class which manages the loading of files in a background thread, 
+  * and syncronizing of loaded models with the main scene graph.*/
+class OSGDB_EXPORT DatabasePager : public osg::NodeVisitor::DatabaseRequestHandler, public OpenThreads::Thread
+{
+    public :
+
+        DatabasePager();
+
+        /** Add a request to load a node file to end the the database request list.*/
+        virtual void requestNodeFile(const std::string& fileName,osg::Group* group);
+
+        /** run does the database paging.*/        
+        virtual void run();
+        
+
+        /** Add the loaded data to the scene graph.*/
+        void addLoadedDataToSceneGraph(double timeStamp);
+
+
+        /** Find all PagedLOD nodes in a subgraph and register them with 
+          * the DatabasePager so it can keep track of expired nodes.
+          * note, should be only be called from the update thread. */
+        void registerPagedLODs(osg::Node* subgraph);
+
+
+        /** Set the amount of time that a subgraph will be kept without being visited in the cull traversal
+          * before being removed.*/
+        void setExpiryDelay(double expiryDelay) { _expiryDelay = expiryDelay; }
+        
+        /** Get the amount of time that a subgraph will be kept without being visited in the cull traversal
+          * before being removed.*/
+        double getExpiryDelay() const { return _expiryDelay; }
+
+        /** set whether the removed subgraphs should be deleted in the database thread or not.*/
+        void setDeleteRemovedSubgraphsInDatabaseThread(bool flag) { _deleteRemovedSubgraphsInDatabaseThread = flag; }
+        
+        /** get whether the removed subgraphs should be deleted in the database thread or not.*/
+        bool getDeleteRemovedSubgraphsInDatabaseThread() const { return _deleteRemovedSubgraphsInDatabaseThread; }
+
+        /** Iterate through the active PagedLOD nodes children removing 
+          * children which havn't been visited since specified expiryTime.
+          * note, should be only be called from the update thread. */
+        void removeExpiredSubgraphs(double currentFrameTime);
+        
+        
+        /** Turn the compilation of rendering objects for specfied graphics context on (true) or off(false).*/
+        void setCompileRenderingObjectsForContexID(unsigned int contextID, bool on);
+        
+        /** Get whether the compilation of rendering objects for specfied graphics context on (true) or off(false).*/
+        bool getCompileRenderingObjectsForContexID(unsigned int contextID);
+
+        /** Compile the rendering objects (display lists,texture objects, VBO's) on loaded subgraph.
+          * note, should only be called from the draw thread.*/
+        void compileRenderingObjects(osg::State& state,double& availableTime);
+
+
+    public:
+
+        typedef std::vector< osg::ref_ptr<osg::PagedLOD> > PagedLODList;
+
+        typedef std::vector< osg::ref_ptr<osg::StateSet> > StateSetList;
+        typedef std::vector< osg::ref_ptr<osg::Drawable> > DrawableList;
+        typedef std::pair<StateSetList,DrawableList>       DataToCompile;
+        typedef std::map< unsigned int, DataToCompile >    DataToCompileMap; 
+
+        typedef std::set<unsigned int>                     ActiveGraphicsContexts;
+
+
+    protected :
+
+        virtual ~DatabasePager() {}
+        
+        struct DatabaseRequest : public osg::Referenced
+        {
+            DatabaseRequest():
+                _numOfRequests(0)
+            {}
+        
+            std::string                 _fileName;
+            unsigned int                _numOfRequests;
+            osg::ref_ptr<osg::Group>    _groupForAddingLoadedSubgraph;
+            osg::ref_ptr<osg::Node>     _loadedModel;
+            DataToCompileMap            _dataToCompileMap;
+            
+        };
+        
+        typedef std::vector< osg::ref_ptr<DatabaseRequest> > DatabaseRequestList;
+
+        DatabaseRequestList     _fileRequestList;
+        OpenThreads::Mutex         _fileRequestListMutex;
+        
+        DatabaseRequestList     _dataToCompileList;
+        OpenThreads::Mutex         _dataToCompileListMutex;
+        
+        bool                    _deleteRemovedSubgraphsInDatabaseThread;
+        osg::NodeList           _childrenToDeleteList;
+        OpenThreads::Mutex         _childrenToDeleteListMutex;
+
+        DatabaseRequestList     _dataToMergeList;
+        OpenThreads::Mutex         _dataToMergeListMutex;
+        
+        
+        PagedLODList            _pagedLODList;
+        
+        double                  _expiryDelay;
+
+        ActiveGraphicsContexts  _activeGraphicsContexts;
+
+};
+
+}
+
+#endif