fix legacy songs not showing background at end, but still allow new

songs to not have it

stepmania/src/NotesLoader.h

@@ -18,6 +18,7 @@ public:
 	const set<istring> &GetBlacklistedImages() const { return BlacklistedImages; }
 	static void GetMainAndSubTitlesFromFullTitle( const CString sFullTitle, CString &sMainTitleOut, CString &sSubTitleOut );
 	virtual bool LoadFromDir( CString sPath, Song &out ) = 0;
+	virtual void TidyUpData( Song &song, bool cache ) { }
 	bool Loadable( CString sPath );
 };
 

stepmania/src/NotesLoaderSM.cpp

@@ -470,6 +470,49 @@ bool SMLoader::LoadEdit( CString sEditFilePath, ProfileSlot slot )
 	
 }
 
+void SMLoader::TidyUpData( Song &song, bool cache )
+{
+	/*
+	 * Hack: if the song has any changes at all (so it won't use a random BGA)
+	 * and doesn't end with "-nosongbg-", add a song background BGC.  Remove
+	 * "-nosongbg-" if it exists.
+	 *
+	 * This way, songs that were created earlier, when we added the song BG
+	 * at the end by default, will still behave as expected; all new songs will
+	 * have to add an explicit song BG tag if they want it.  This is really a
+	 * formatting hack only; nothing outside of SMLoader ever sees "-nosongbg-".
+	 */
+	vector<BackgroundChange> &bg = song.m_BackgroundChanges;
+	if( !bg.empty() )
+	{
+		/* BGChanges have been sorted.  On the odd chance that a BGChange exists
+		* with a very high beat, search the whole list. */
+		bool bHasNoSongBgTag = false;
+
+		for( unsigned i = 0; !bHasNoSongBgTag && i < bg.size(); ++i )
+		{
+			if( !bg[i].m_sBGName.CompareNoCase("-nosongbg-") )
+			{
+				bg.erase( bg.begin()+i );
+				bHasNoSongBgTag = true;
+			}
+		}
+
+		/*
+		 * If we're loading cache, -nosongbg- should always be in there.  We must
+		 * not call IsAFile(song.GetBackgroundPath()) when loading cache.
+		 *
+		 * If BGChanges already exist after the last beat, don't add the background
+		 * in the middle.
+		 */
+		if( !cache &&
+		    bg.back().m_fStartBeat-0.0001f < song.m_fLastBeat &&
+			!bHasNoSongBgTag &&
+			IsAFile( song.GetBackgroundPath() ) )
+			bg.push_back( BackgroundChange(song.m_fLastBeat,song.m_sBackgroundFile) );
+	}
+}
+
 /*
  * (c) 2001-2004 Chris Danford, Glenn Maynard
  * All rights reserved.

stepmania/src/NotesLoaderSM.h

@@ -34,6 +34,7 @@ public:
 
 	void GetApplicableFiles( CString sPath, CStringArray &out );
 	bool LoadFromDir( CString sPath, Song &out );
+	void TidyUpData( Song &song, bool cache );
 	static bool LoadTimingFromFile( const CString &fn, TimingData &out );
 	static void LoadTimingFromSMFile( const MsdFile &msd, TimingData &out );
 	static bool LoadEdit( CString sEditFilePath, ProfileSlot slot );

stepmania/src/NotesWriterSM.cpp

@@ -85,10 +85,14 @@ void NotesWriterSM::WriteGlobalTags( RageFile &f, const Song &out )
 	{
 		const BackgroundChange &seg = out.m_BackgroundChanges[i];
 
-		f.PutLine( ssprintf( "%.3f=%s=%.3f=%d=%d=%d", seg.m_fStartBeat, seg.m_sBGName.c_str(), seg.m_fRate, seg.m_bFadeLast, seg.m_bRewindMovie, seg.m_bLoop ) );
-		if( i != out.m_BackgroundChanges.size()-1 )
-			f.Write( "," );
+		f.PutLine( ssprintf( "%.3f=%s=%.3f=%d=%d=%d,", seg.m_fStartBeat, seg.m_sBGName.c_str(), seg.m_fRate, seg.m_bFadeLast, seg.m_bRewindMovie, seg.m_bLoop ) );
 	}
+	/* If there's an animation plan at all, add a dummy "-nosongbg-" tag to indicate that
+	 * this file doesn't want a song BG entry added at the end.  See SMLoader::TidyUpData.
+	 * This tag will be removed on load.  Add it at a very high beat, so it won't cause
+	 * problems if loaded in older versions. */
+	if( !out.m_BackgroundChanges.empty() )
+		f.PutLine( "99999=-nosongbg-=1.000=0=0=0 // don't automatically add -songbackground-" );
 	f.PutLine( ";" );
 
 	if( out.m_ForegroundChanges.size() )

stepmania/src/Song.cpp

@@ -229,6 +229,7 @@ bool Song::LoadFromSongDir( CString sDir )
 //		LOG->Trace( "Loading '%s' from cache file '%s'.", m_sSongDir.c_str(), GetCacheFilePath().c_str() );
 		SMLoader ld;
 		ld.LoadFromSMFile( GetCacheFilePath(), *this, true );
+		ld.TidyUpData( *this, true );
 	}
 	else
 	{
@@ -246,12 +247,17 @@ bool Song::LoadFromSongDir( CString sDir )
 
 		bool success = ld->LoadFromDir( sDir, *this );
 		BlacklistedImages = ld->GetBlacklistedImages();
-		delete ld;
 
 		if(!success)
+		{
+			delete ld;
 			return false;
+		}
 
 		TidyUpData();
+		ld->TidyUpData( *this, false );
+
+		delete ld;
 
 		// save a cache file so we don't have to parse it all over again next time
 		SaveToCacheFile();