New Preference: OnlyPreferredDifficulties -- Drops songs that don't have steps of the preferred difficulty for the primary player. Useful if you want to simulate games that lock you to a difficulty after a style/mode selection.

stepmania/Themes/default/Languages/en.ini

@@ -286,6 +286,7 @@ AutoMapOnJoyChange=&oq;ON&cq; will cause the game to automatically remap all the
 AutoPlay=This option is useful for those who would like to play without using a pad.  However, you will not be able to set high scores or earn extra stages while this options is ON.
 AutogenGroupCourses=Show group Nonstop and Endless courses that were created by Autogen.
 AutogenSteps=Automatically generate steps from other game types.
+OnlyPreferredDifficulties=Only display songs that have the preferred difficulty of the first player.
 BGBrightness=Controls how bright the background will appear. Turn this setting down if you have a hard time seeing the notes.
 Background=Change options that control the backgrounds that play during gameplay.
 BarDrain=BarDrain
@@ -703,6 +704,7 @@ AutoMapOnJoyChange=Auto Map On Joy Change
 AutoPlay=AutoPlay
 AutogenGroupCourses=Autogen Group Courses
 AutogenSteps=Autogen Steps
+OnlyPreferredDifficulties=Only Show Preferred Difficulties
 BGBrightness=Brightness
 Background=Background
 BarDrain=Bar Drain

stepmania/Themes/default/metrics.ini

@@ -2747,7 +2747,7 @@ IdleTimeoutSeconds=0
 
 [ScreenOptionsAdvanced]
 Fallback="ScreenOptionsServiceChild"
-LineNames="1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30"
+LineNames="1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31"
 Line1="conf,MenuTimer"
 Line2="conf,ScoringType"
 Line3="conf,TimingWindowScale"
@@ -2778,6 +2778,7 @@ Line27="conf,MusicWheelSwitchSpeed"
 Line28="conf,AutogenSteps"
 Line29="conf,AutogenGroupCourses"
 Line30="conf,FastLoad"
+Line31="conf,OnlyPreferredDifficulties"
 
 [ScreenOptionsGraphicsSound]
 Fallback="ScreenOptionsServiceChild"

stepmania/src/MusicWheel.cpp

@@ -363,9 +363,22 @@ void MusicWheel::GetSongList( vector<Song*> &arraySongs, SortOrder so, const RSt
 		if( (so!=SORT_ROULETTE || !RANDOM_PICKS_LOCKED_SONGS) && iLocked )
 			continue;
 
-		// If the song has at least one steps, add it.
-		if( pSong->HasStepsType(GAMESTATE->GetCurrentStyle()->m_StepsType) )
-			arraySongs.push_back( pSong );
+
+		if(PREFSMAN->m_bOnlyPreferredDifficulties)
+		{
+			// if the song has steps that fit the preferred difficulty of the default player
+			if(pSong->HasStepsTypeAndDifficulty(GAMESTATE->GetCurrentStyle()->m_StepsType,GAMESTATE->m_PreferredDifficulty[GAMESTATE->GetFirstHumanPlayer()]) )
+				arraySongs.push_back( pSong );
+		}
+		else
+		{
+			// If the song has at least one steps, add it.
+			if( pSong->HasStepsType(GAMESTATE->GetCurrentStyle()->m_StepsType) )
+				arraySongs.push_back( pSong );
+
+		}
+
+		
 	}
 
 	/* Hack: Add extra stage item if it was eliminated for any reason (eg. it's a long

stepmania/src/PrefsManager.cpp

@@ -207,6 +207,7 @@ PrefsManager::PrefsManager() :
 	m_bDisqualification		( "Disqualification",			false ),
 	m_bAutogenSteps			( "AutogenSteps",			true ),
 	m_bAutogenGroupCourses		( "AutogenGroupCourses",		true ),
+	m_bOnlyPreferredDifficulties ( "OnlyPreferredDifficulties", false ),
 	m_bBreakComboToGetItem		( "BreakComboToGetItem",		false ),
 	m_bLockCourseDifficulties	( "LockCourseDifficulties",		true ),
 	m_ShowDancingCharacters		( "ShowDancingCharacters",		SDC_Random ),

stepmania/src/PrefsManager.h

@@ -195,6 +195,7 @@ public:
 	Preference<bool>	m_bDisqualification;
 	Preference<bool>	m_bAutogenSteps;
 	Preference<bool>	m_bAutogenGroupCourses;
+	Preference<bool>	m_bOnlyPreferredDifficulties;
 	Preference<bool>	m_bBreakComboToGetItem;
 	Preference<bool>	m_bLockCourseDifficulties;
 	Preference<ShowDancingCharacters>		m_ShowDancingCharacters;

stepmania/src/ScreenOptionsMasterPrefs.cpp

@@ -633,6 +633,7 @@ static void InitializeConfOptions()
 
 	/* Misc options */
 	ADD( ConfOption( "AutogenSteps",		MovePref<bool>,		"Off","On" ) );
+	ADD( ConfOption( "OnlyPreferredDifficulties", MovePref<bool>, "Off","On" ) );
 	g_ConfOptions.back().m_iEffects = OPT_APPLY_SONG;
 
 	ADD( ConfOption( "AutogenGroupCourses",		MovePref<bool>,		"Off","On" ) );