Fix #1878

include/Engine.h

@@ -46,7 +46,7 @@ class EXPORT Engine : public QObject
 {
 	Q_OBJECT
 public:
-	static void init();
+	static void init( bool renderOnly );
 	static void destroy();
 
 	// core

include/Mixer.h

@@ -382,7 +382,7 @@ private:
 	} ;
 
 
-	Mixer();
+	Mixer( bool renderOnly );
 	virtual ~Mixer();
 
 	void startProcessing( bool _needs_fifo = true );

src/core/Engine.cpp

@@ -50,7 +50,7 @@ DummyTrackContainer * Engine::s_dummyTC = NULL;
 
 
 
-void Engine::init()
+void Engine::init( bool renderOnly )
 {
 	Engine *engine = inst();
 
@@ -60,7 +60,7 @@ void Engine::init()
 
 	emit engine->initProgress(tr("Initializing data structures"));
 	s_projectJournal = new ProjectJournal;
-	s_mixer = new Mixer;
+	s_mixer = new Mixer( renderOnly );
 	s_song = new Song;
 	s_fxMixer = new FxMixer;
 	s_bbTrackContainer = new BBTrackContainer;

src/core/Mixer.cpp

@@ -57,7 +57,7 @@
 
 
 
-Mixer::Mixer() :
+Mixer::Mixer( bool renderOnly ) :
 	m_framesPerPeriod( DEFAULT_BUFFER_SIZE ),
 	m_workingBuf( NULL ),
 	m_inputBufferRead( 0 ),
@@ -82,38 +82,34 @@ Mixer::Mixer() :
 		clearAudioBuffer( m_inputBuffer[i], m_inputBufferSize[i] );
 	}
 
-	// just rendering?
-	if( !gui )
+	// determine FIFO size and number of frames per period
+	int fifoSize = 1;
+
+	if (!renderOnly)
 	{
-		m_framesPerPeriod = DEFAULT_BUFFER_SIZE;
-		m_fifo = new fifo( 1 );
-	}
-	else if( ConfigManager::inst()->value( "mixer", "framesperaudiobuffer"
-						).toInt() >= 32 )
-	{
-		m_framesPerPeriod =
-			(fpp_t) ConfigManager::inst()->value( "mixer",
-					"framesperaudiobuffer" ).toInt();
+		m_framesPerPeriod = 
+			( fpp_t ) ConfigManager::inst()->
+				value( "mixer", "framesperaudiobuffer" ).toInt();
+
+		if (m_framesPerPeriod < 32)
+		{
+			ConfigManager::inst()->setValue( "mixer",
+									"framesperaudiobuffer",
+						QString::number( DEFAULT_BUFFER_SIZE ) );
+
+			m_framesPerPeriod = DEFAULT_BUFFER_SIZE;
+		}
 
 		if( m_framesPerPeriod > DEFAULT_BUFFER_SIZE )
 		{
-			m_fifo = new fifo( m_framesPerPeriod
-							/ DEFAULT_BUFFER_SIZE );
+			fifoSize = m_framesPerPeriod / DEFAULT_BUFFER_SIZE;
 			m_framesPerPeriod = DEFAULT_BUFFER_SIZE;
 		}
-		else
-		{
-			m_fifo = new fifo( 1 );
-		}
-	}
-	else
-	{
-		ConfigManager::inst()->setValue( "mixer",
-							"framesperaudiobuffer",
-				QString::number( m_framesPerPeriod ) );
-		m_fifo = new fifo( 1 );
 	}
 
+	// allocte the FIFO from the determined size
+	m_fifo = new fifo( fifoSize );
+
 	// now that framesPerPeriod is fixed initialize global BufferManager
 	BufferManager::init( m_framesPerPeriod );
 

src/core/main.cpp

@@ -509,7 +509,7 @@ int main( int argc, char * * argv )
 	else
 	{
 		// we're going to render our song
-		Engine::init();
+		Engine::init( true );
 
 		printf( "loading project...\n" );
 		Engine::getSong()->loadProject( file_to_load );

src/gui/GuiApplication.cpp

@@ -90,7 +90,7 @@ GuiApplication::GuiApplication()
 		this, SLOT(displayInitProgress(const QString&)));
 
 	// Init central engine which handles all components of LMMS
-	Engine::init();
+	Engine::init(false);
 
 	s_instance = this;
 
@@ -188,4 +188,4 @@ void GuiApplication::childDestroyed(QObject *obj)
 	{
 		m_controllerRackView = nullptr;
 	}
-}
+}