Resolved race condition when pausing render preview

src/LibVLCpp/VLCMediaPlayer.cpp

@@ -174,7 +174,7 @@ void                            MediaPlayer::takeSnapshot( const char* outputFil
     CheckVlcppException( m_ex );
 }
 
-bool                                MediaPlayer::isPlaying()
+bool                            MediaPlayer::isPlaying()
 {
     int res = libvlc_media_player_is_playing( m_internalPtr, m_ex );
     CheckVlcppException( m_ex );

src/Workflow/ClipWorkflow.cpp

@@ -93,7 +93,7 @@ void    ClipWorkflow::lock( ClipWorkflow* cw, void** pp_ret )
 //    else
 //    {
         *pp_ret = cw->m_buffer;
-//        qDebug() << "Clip workflow locking <<<<<<<<<<<<<<<<<<<<<<<<<<";
+        qDebug() << "Clip workflow locking <<<<<<<<<<<<<<<<<<<<<<<<<<";
 //    }
 }
 
@@ -114,8 +114,10 @@ void    ClipWorkflow::unlock( ClipWorkflow* cw )
     {
         QMutexLocker    lock( cw->m_condMutex );
 
+        qDebug() << "Setting state to Sleeping";
         cw->m_state = Sleeping;
         cw->m_stateLock->unlock();
+        //Signal that render has been completed.
         cw->m_renderWaitCond->wake();
 
         qDebug() << "Entering condwait";

src/Workflow/TrackWorkflow.cpp

@@ -342,8 +342,9 @@ void            TrackWorkflow::pauseClipWorkflow( ClipWorkflow* cw )
          cw->getState() == ClipWorkflow::EndReached )
     {
         qDebug() << "Pausing a sleeping, ready or EndReached ClipWorkflow, state =" << cw->getState();
-        cw->getStateLock()->unlock();
         cw->queryStateChange( ClipWorkflow::Pausing );
+        qDebug() << "Unlocked state mutex";
+        cw->getStateLock()->unlock();
         cw->wake();
     }
     else if ( cw->getState() == ClipWorkflow::Rendering )

src/renderer/WorkflowRenderer.cpp

@@ -85,6 +85,9 @@ void*   WorkflowRenderer::lock( void* datas )
 {
     WorkflowRenderer* self = reinterpret_cast<WorkflowRenderer*>( datas );
 
+    //If we're not playing, then where in a paused media player.
+    if ( self->m_mediaPlayer->isPlaying() == false )
+        return self->m_lastFrame;
     if ( self->m_oneFrameOnly < 2 )
     {
         qDebug() << "\nQuerying new picture";
@@ -122,6 +125,7 @@ void        WorkflowRenderer::checkActions()
         switch ( act )
         {
             case    Pause:
+                qDebug() << "Pausing WorkflowRenderer mediaPlayer";
                 m_mediaPlayer->pause();
                 //This will also pause the MainWorkflow via a signal/slot
                 break ;