Source/Contrib/BackgroundLoader/OSGBackgroundLoader.h

   1 #ifndef _OSG_BACKGROUND_LOADER_H_
   2 #define _OSG_BACKGROUND_LOADER_H_
   3
   4 #include "OSGContribBackgroundLoaderDef.h"
   5
   6 #include "OSGBaseTypes.h"
   7 #include "OSGSingletonHolder.h"
   8 #include "OSGRequest.h"
   9 #include "OSGThread.h"
  10 #include "OSGLock.h"
  11 #include "OSGCondVar.h"
  12
  13 #include <deque>
  14
  15 OSG_BEGIN_NAMESPACE
  16
  17 /** Helper class that supports processing requests
  18  * such as loading files in a background thread.
  19  */
  20
  21 class OSG_CONTRIBBACKGROUNDLOADER_DLLMAPPING BackgroundLoaderBase
  22 {
  23   public:
  24
  25     typedef std::vector<std::string> desc_list_t;
  26
  27   public:
  28
  29     /**
  30      * Start load thread and start handling background requests.
  31      */
  32     void start(const OSG::UInt16 numThreads = 1);
  33
  34     /**
  35      * Stop load thread and handling background requests.
  36      */
  37     void stop(void);
  38
  39     /** Add a new request to the queue to be processed. */
  40     void addRequest(RequestPtr req);
  41
  42     /** Request removal of an existing request.
  43      * If request is found, it is removed.
  44      */
  45     void removeRequest(RequestPtr req);
  46
  47     /** Sync up with the background loader and it's pending changes.
  48      * @args reqLimit The max number of requests to process.  0-All
  49      */
  50     void sync(unsigned reqLimit = 0);
  51
  52     /** Process a single request.
  53      * This method can only be called if we are not running
  54      * in a background thread but instead want to run synchronously.
  55      */
  56     void processOne(void);
  57
  58    /** Return the number of pending requests. */
  59    unsigned getNumPendingRequests(void);
  60
  61    /** Return a list of the descriptions of all pending requests. */
  62    desc_list_t getPendingDescriptionList();
  63
  64   protected:
  65
  66    //void workerThread(void *);
  67    //void renderThread(void *);
  68    BackgroundLoaderBase(void);
  69    virtual ~BackgroundLoaderBase(void);
  70
  71    static void loadProc(void* arg);
  72
  73 private:
  74
  75    template <class SingletonT>
  76    friend class SingletonHolder;
  77
  78    /** default function (move to 'public' if needed). */
  79    BackgroundLoaderBase(const BackgroundLoaderBase &source);
  80
  81    /** \brief prohibit default function (move to 'public' if needed) */
  82    void operator =(const BackgroundLoaderBase &source);
  83
  84    typedef std::list<RequestPtr> request_queue_t;
  85    request_queue_t               mPendingRequests;
  86    request_queue_t               mFinishedRequests;
  87    std::vector<ThreadRefPtr>     mLoadThreads;
  88    LockRefPtr                    mFinishedLock;
  89    CondVarRefPtr                 mLoadCondVar;           // Cond var to protect
  90                                                          // the request queue
  91    bool                          mStopRunning;
  92 };
  93
  94 #if defined(WIN32)
  95 OSG_CONTRIBBACKGROUNDLOADER_EXPIMP_TMPL
  96 template class OSG_CONTRIBBACKGROUNDLOADER_DLLMAPPING
  97     SingletonHolder<BackgroundLoaderBase>;
  98 #endif
  99
 100 typedef SingletonHolder<BackgroundLoaderBase> BackgroundLoader;
 101
 102 OSG_END_NAMESPACE
 103
 104 #endif /*_OSG_BACKGROUND_LOADER_H_*/