Add Screen::FirstUpdate().

stepmania/src/Screen.cpp

@@ -16,6 +16,7 @@
 
 Screen::Screen()
 {
+	m_FirstUpdate = true;
 }
 
 Screen::~Screen()
@@ -100,4 +101,11 @@ void Screen::SendScreenMessage( ScreenMessage SM, float fDelay )
 	QSM.SM = SM;
 	QSM.fDelayRemaining = fDelay;
 	m_QueuedMessages.Add( QSM );
-}
+}
+
+bool Screen::FirstUpdate()
+{ 
+	bool ret = m_FirstUpdate;
+	m_FirstUpdate = false;
+	return ret;
+}

stepmania/src/Screen.h

@@ -40,6 +40,9 @@ public:
 	void SendScreenMessage( const ScreenMessage SM, const float fDelay );
 	void ClearMessageQueue() { m_QueuedMessages.SetSize(0,5); };
 
+	/* Used only by ScreenManager::Update. */
+	bool FirstUpdate();
+
 protected:
 
 	// structure for holding messages sent to a Screen
@@ -65,4 +68,7 @@ public:
 	virtual void MenuRight( PlayerNumber p )	{};
 	virtual void MenuStart( PlayerNumber p )	{};
 	virtual void MenuBack(	PlayerNumber p )	{};
+
+private:
+	bool m_FirstUpdate;
 };