require "[Screen] Class=foo" so that derived classes can inhereit "Class=" and not have to redefine it

stepmania/Themes/default/metrics.ini

@@ -189,6 +189,7 @@ BounceJoinMessage=1
 FoldOnJoin=1
 
 [ScreenSelectStyle]
+Class=ScreenSelectStyle
 Fallback=ScreenWithMenuElements
 ChoiceNames=1,2,3,4,5
 # The "name" here affects the announcer, eg. "ScreenSelectStyle comment single".
@@ -309,6 +310,7 @@ TimerSeconds=0
 TimerStealth=0
 
 [ScreenSelectDifficulty]
+Class=ScreenSelectDifficulty
 Fallback=ScreenWithMenuElements
 ChoiceNames=1,2,3,4,5,6,7,8
 Choice1=PlayMode,regular;Difficulty,beginner;name,beginner
@@ -436,6 +438,7 @@ OKOffCommand=sleep,0.2;linear,0.3;zoom,0
 DisabledColor=0.2,0.2,0.2,1
 
 [ScreenSelectGroup]
+Class=ScreenSelectGroup
 NextScreen=ScreenInstructions
 PrevScreen=ScreenTitleBranch
 Fallback=ScreenWithMenuElements
@@ -499,6 +502,7 @@ CropWidth=146
 InitCommand=horizalign,left;vertalign,top;shadowlength,2;zoom,0.5;
 
 [ScreenInstructions]
+Class=ScreenInstructions
 Fallback=ScreenWithMenuElements
 NextScreen=ScreenSelectCharacter
 PrevScreen=ScreenTitleBranch
@@ -507,6 +511,7 @@ StyleIcon=1
 MemoryCardIcons=1
 
 [ScreenSelectMusic]
+Class=ScreenSelectMusic
 Fallback=ScreenWithMenuElements
 NonPresenceP1X=-128
 NonPresenceP1Y=SCREEN_CENTER_Y+0
@@ -983,6 +988,7 @@ StyleIcon=0
 MemoryCardIcons=0
 
 [ScreenStage]
+Class=ScreenStage
 NextScreen=@SelectGameplayScreen()
 PrevScreen=@SongSelectionScreen()
 // This is the minimum delay after the "in" transition before the
@@ -1016,6 +1022,7 @@ OverlayOnCommand=
 OverlayOffCommand=
 
 [ScreenGameplay]
+Class=ScreenGameplay
 ShowEvaluationOnFail=0
 StaticBGY=SCREEN_CENTER_Y+0
 StaticBGX=SCREEN_CENTER_X+0
@@ -2226,7 +2233,9 @@ TextZoom=0.8
 NextScreen=ScreenRanking
 
 [ScreenEditMenu]
+Class=ScreenEditMenu
 Fallback=ScreenWithMenuElements
+PrevScreen=ScreenTitleBranch
 ExplanationX=SCREEN_CENTER_X+0
 ExplanationY=SCREEN_CENTER_Y+170
 ExplanationOnCommand=wrapwidthpixels,900;zoom,0.7
@@ -2251,6 +2260,7 @@ Line3=Difficulties
 Line4=list,RandomModifiers
 
 [ScreenEditCoursesMenu]
+Class=ScreenEditCoursesMenu
 Fallback=ScreenWithMenuElements
 NextScreen=ScreenTitleBranch
 ExplanationX=SCREEN_CENTER_X+0
@@ -2499,6 +2509,7 @@ MoreExitUnselectedP1Command=
 MoreExitUnselectedP2Command=
 
 [ScreenMapControllers]
+Class=ScreenMapControllers
 Fallback=ScreenOperatorMenu
 EvenLineIn=addx,-SCREEN_WIDTH;decelerate,0.5;addx,SCREEN_WIDTH;
 OddLineIn=addx,SCREEN_WIDTH;decelerate,0.5;addx,-SCREEN_WIDTH;
@@ -2506,18 +2517,23 @@ EvenLineOut=stoptweening;accelerate,0.3;addx,-SCREEN_WIDTH;
 OddLineOut=stoptweening;accelerate,0.3;addx,SCREEN_WIDTH;
 
 [ScreenCenterImage]
+Class=ScreenCenterImage
 Fallback=ScreenOperatorMenu
 
 [ScreenTestInput]
+Class=ScreenTestInput
 Fallback=ScreenOperatorMenu
 
 [ScreenTestLights]
+Class=ScreenTestLights
 Fallback=ScreenOperatorMenu
 
 [ScreenNetworkOptions]
+Class=ScreenNetworkOptions
 Fallback=ScreenOperatorMenu
 
 [ScreenBookkeeping]
+Class=ScreenBookkeeping
 Fallback=ScreenOperatorMenu
 
 [ScreenPackages]
@@ -3023,6 +3039,7 @@ Line2=conf,AttractSoundFrequency
 Line3=conf,SoundVolume
 
 [ScreenProfileOptions]
+Class=ScreenProfileOptions
 Fallback=ScreenOperatorMenu
 Player1Profile=
 Player2Profile=
@@ -3253,6 +3270,7 @@ Fallback=ScreenAttract
 NextScreen=ScreenLogo
 
 [ScreenLogo]
+Class=ScreenLogo
 Fallback=ScreenAttract
 //Not used in default theme, but without, will cause warning
 LogoY=0
@@ -3293,6 +3311,7 @@ DifficultiesToShow=easy,medium
 ShowCourseModifiers=0
 
 [ScreenNameEntry]
+Class=ScreenNameEntry
 TimerX=SCREEN_CENTER_X+0
 TimerY=SCREEN_CENTER_Y-210
 CategoryY=SCREEN_CENTER_Y+190
@@ -3491,6 +3510,7 @@ NextScreen2=screen,ScreenNetSelectMusic
 NextScreen3=screen,ScreenSelectMusic
 
 [ScreenPlayerOptions]
+Class=ScreenPlayerOptions
 Fallback=ScreenOptions
 PrevScreen=@SongSelectionScreen()
 NextScreen=ScreenSongOptions
@@ -3542,6 +3562,7 @@ Line4=list,Persp
 Line5=Steps
 
 [ScreenSongOptions]
+Class=ScreenSongOptions
 Fallback=ScreenOptions
 PrevScreen=@SelectFirstOptionsScreen()
 NextScreen=ScreenStage
@@ -3587,6 +3608,7 @@ Class=ScreenAttract
 NextScreen=ScreenCompany
 
 [ScreenSelectCharacter]
+Class=ScreenSelectCharacter
 Fallback=ScreenWithMenuElements
 TitleP1OnCommand=x,140;y,80;addx,-SCREEN_WIDTH*0.6;bounceend,0.5;addx,SCREEN_WIDTH*0.6
 TitleP1OffCommand=sleep,0.2;bouncebegin,0.5;addx,-SCREEN_WIDTH*0.6
@@ -3878,6 +3900,7 @@ RandomModifiers,1=name,Off
 RandomModifiers,2=mod,random;name,Random
 
 [ScreenReloadSongs]
+Class=ScreenReloadSongs
 NextScreen=ScreenTitleBranch
 
 [DancingCharacters]
@@ -3948,6 +3971,7 @@ Fallback=DifficultyMeter
 Fallback=DifficultyMeter
 
 [ScreenEdit]
+Class=ScreenEdit
 OverlayX=0
 OverlayY=0
 OverlayOnCommand=

stepmania/src/ScreenManager.cpp

@@ -232,10 +232,7 @@ Screen* ScreenManager::MakeNewScreen( const CString &sScreenName )
 	RageTimer t;
 	LOG->Trace( "Loading screen name '%s'", sScreenName.c_str() );
 
-	CString sClassName = sScreenName;
+	CString sClassName = THEME->GetMetric(sScreenName,"Class");
-	// Look up the class in the metrics group sName
-	if( THEME->HasMetric(sClassName,"Class") )
-		sClassName = THEME->GetMetric(sClassName,"Class");
 	
 	map<CString,CreateScreenFn>::iterator iter = g_pmapRegistrees->find( sClassName );
 	ASSERT_M( iter != g_pmapRegistrees->end(), ssprintf("Screen '%s' has an invalid class '%s'",sScreenName.c_str(),sClassName.c_str()) )