restore autogen lights

src/PrefsManager.cpp

@@ -275,7 +275,7 @@ PrefsManager::PrefsManager() :
 	m_iSoundDevice			( "SoundDevice",			"" ),
 	m_iRageSoundSampleCountClamp	("RageSoundSampleCountClamp", 0), //some sound drivers mask the sample location number, the most popular number for this is 2^27, this causes lockup after ~50 minutes at 44.1khz sample rate
 	m_iSoundPreferredSampleRate	( "SoundPreferredSampleRate",		0 ),
-	m_sLightsStepsDifficulty	( "LightsStepsDifficulty",		"medium" ),
+	m_sLightsStepsDifficulty	( "LightsStepsDifficulty",		"hard,medium" ),
 	m_bAllowUnacceleratedRenderer	( "AllowUnacceleratedRenderer",		false ), 
 	m_bThreadedInput		( "ThreadedInput",			true ),
 	m_bThreadedMovieDecode		( "ThreadedMovieDecode",		true ),

src/ScreenGameplay.cpp

@@ -1452,6 +1452,27 @@ void ScreenGameplay::LoadLights()
 	NoteData TapNoteData1;
 	pSteps->GetNoteData( TapNoteData1 );
 
+	//taken from oitg, restores arrow -> marquee/bass light mapping.
+	if( asDifficulties.size() > 1 )
+	{
+		Difficulty d2 = StringToDifficulty( asDifficulties[1] );
+
+		Steps *pSteps2;
+
+		pSteps2 = SongUtil::GetClosestNotes( GAMESTATE->m_pCurSong, st, d2 );
+
+		if(pSteps2 != nullptr)
+		{
+			NoteData TapNoteData2;
+			pSteps2->GetNoteData( TapNoteData2 );
+
+			NoteDataUtil::LoadTransformedLightsFromTwo( TapNoteData1, TapNoteData2, m_CabinetLightsNoteData );
+			return;
+		}
+
+		/* fall through */
+	}
+
 	NoteDataUtil::LoadTransformedLights( TapNoteData1, m_CabinetLightsNoteData, GAMEMAN->GetStepsTypeInfo(StepsType_lights_cabinet).iNumTracks );
 }