Adds a metric feature to force static backgrounds off during gameplay (useful if you just want videos and no static bg before the song) doesn't turn off the background at the end of the song yet (todo).

stepmania/Themes/default/metrics.ini

@@ -2332,6 +2332,7 @@ BottomEdge=SCREEN_BOTTOM
 BrightnessOverlayFadeCommand=
 ClampOutputPercent=0
 ShowDancingCharacters=true
+DontUseStaticBackground=false
 
 [Judgment]
 JudgmentW1Command=shadowlength,0;diffusealpha,1;zoom,1.3;linear,0.05;zoom,1;sleep,0.8;linear,0.1;zoomy,0.5;zoomx,2;diffusealpha,0;glowblink;effectperiod,0.05;effectcolor1,1,1,1,0;effectcolor2,1,1,1,0.8

stepmania/src/Background.cpp

@@ -30,6 +30,7 @@ static ThemeMetric<float> BOTTOM_EDGE				("Background","BottomEdge");
 #define RECT_BACKGROUND RectF					(LEFT_EDGE,TOP_EDGE,RIGHT_EDGE,BOTTOM_EDGE)
 static ThemeMetric<float> CLAMP_OUTPUT_PERCENT			("Background","ClampOutputPercent");
 static ThemeMetric<bool> SHOW_DANCING_CHARACTERS		("Background","ShowDancingCharacters");
+static ThemeMetric<bool> DONT_USE_STATIC_BG		("Background","DontUseStaticBackground");
 
 
 static Preference<bool>	g_bShowDanger( "ShowDanger", true );
@@ -169,6 +170,12 @@ void BackgroundImpl::Init()
 	m_bDangerAllWasVisible = false;
 	m_StaticBackgroundDef = BackgroundDef();
 	
+	if( DONT_USE_STATIC_BG )
+	{
+		m_StaticBackgroundDef.m_sColor1 = "0,0,0,0";
+		m_StaticBackgroundDef.m_sColor2 = "0,0,0,0";
+	}
+
 	// load transitions
 	{
 		ASSERT( m_mapNameToTransition.empty() );
@@ -582,6 +589,7 @@ void BackgroundImpl::LoadFromSong( const Song* pSong )
 
 		// end showing the static song background
 		BackgroundChange change;
+
 		change.m_def = m_StaticBackgroundDef;
 		change.m_fStartBeat = pSong->m_fLastBeat;
 		layer.m_aBGChanges.push_back( change );
@@ -604,6 +612,7 @@ void BackgroundImpl::LoadFromSong( const Song* pSong )
 	{
 		BackgroundChange change;
 		change.m_def = m_StaticBackgroundDef;
+
 		change.m_fStartBeat = -10000;
 		mainlayer.m_aBGChanges.insert( mainlayer.m_aBGChanges.begin(), change );
 	}