Instead of loading Defaults.ini underneith Preferences.ini, change the

actual IPreference defaults according to Defaults.ini.  This way, we can
access default values immediately, without having to load and parse a
file.  Since this simply changes the value in the preference, this doesn't
use any more memory.

stepmania/src/Preference.cpp

@@ -51,6 +51,14 @@ void IPreference::SavePrefsToNode( XNode* pNode )
 		(*p)->WriteTo( pNode );
 }
 
+void IPreference::ReadAllDefaultsFromNode( const XNode* pNode )
+{
+	if( pNode == NULL )
+		return;
+	FOREACHS_CONST( IPreference*, *m_Subscribers.m_pSubscribers, p )
+		(*p)->ReadDefaultFrom( pNode );
+}
+
 void IPreference::PushValue( lua_State *L ) const
 {
 	if( LOG )
@@ -101,6 +109,15 @@ void IPreference::WriteTo( XNode* pNode ) const
 	pNode->AppendAttr( m_sName, ToString() );
 }
 
+/* Load our value from the node, and make it the new default. */
+void IPreference::ReadDefaultFrom( const XNode* pNode )
+{
+	CString sVal;
+	if( !pNode->GetAttrValue(m_sName, sVal) )
+		return;
+	SetDefaultFromString( sVal );
+}
+
 void BroadcastPreferenceChanged( const CString& sPreferenceName )
 {
 	if( MESSAGEMAN )

stepmania/src/Preference.h

@@ -15,8 +15,10 @@ public:
 	virtual ~IPreference();
 	void ReadFrom( const XNode* pNode );
 	void WriteTo( XNode* pNode ) const;
+	void ReadDefaultFrom( const XNode* pNode );
 
 	virtual void LoadDefault() = 0;
+	virtual void SetDefaultFromString( const CString &s ) = 0;
 
 	virtual CString ToString() const = 0;
 	virtual void FromString( const CString &s ) = 0;
@@ -30,6 +32,7 @@ public:
 	static void LoadAllDefaults();
 	static void ReadAllPrefsFromNode( const XNode* pNode );
 	static void SavePrefsToNode( XNode* pNode );
+	static void ReadAllDefaultsFromNode( const XNode* pNode );
 
 protected:
 	CString		m_sName;
@@ -63,6 +66,10 @@ public:
 	{
 		m_currentValue = m_defaultValue;
 	}
+	void SetDefaultFromString( const CString &s )
+	{
+		PrefFromString( s, (BasicType &)m_defaultValue  );
+	}
 
 	const T &Get() const
 	{

stepmania/src/PrefsManager.cpp

@@ -379,7 +379,9 @@ void PrefsManager::RestoreGamePrefs()
 
 void PrefsManager::ReadPrefsFromDisk()
 {
-	ReadPrefsFromFile( DEFAULTS_INI_PATH, GetPreferencesSection() );
+	ReadDefaultsFromFile( DEFAULTS_INI_PATH, GetPreferencesSection() );
+	IPreference::LoadAllDefaults();
+
 	ReadPrefsFromFile( SpecialFiles::PREFERENCES_INI_PATH, "Options" );
 	ReadGamePrefsFromIni( SpecialFiles::PREFERENCES_INI_PATH );
 	ReadPrefsFromFile( STATIC_INI_PATH, GetPreferencesSection() );
@@ -392,7 +394,7 @@ void PrefsManager::ResetToFactoryDefaults()
 {
 	// clobber the users prefs by initing then applying defaults
 	Init();
-	ReadPrefsFromFile( DEFAULTS_INI_PATH, GetPreferencesSection() );
+	IPreference::LoadAllDefaults();
 	ReadPrefsFromFile( STATIC_INI_PATH, GetPreferencesSection() );
 	
 	SavePrefsToDisk();
@@ -454,6 +456,26 @@ void PrefsManager::ReadGamePrefsFromIni( const CString &sIni )
 	}
 }
 
+void PrefsManager::ReadDefaultsFromFile( const CString &sIni, const CString &sSection )
+{
+	IniFile ini;
+	if( !ini.ReadFile(sIni) )
+		return;
+
+	ReadDefaultsFromIni( ini, sSection );
+}
+
+void PrefsManager::ReadDefaultsFromIni( const IniFile &ini, const CString &sSection )
+{
+	// Apply our fallback recursively (if any) before applying ourself.
+	// TODO: detect circular?
+	CString sFallback;
+	if( ini.GetValue(sSection,"Fallback",sFallback) )
+		ReadDefaultsFromIni( ini, sFallback );
+
+	IPreference::ReadAllDefaultsFromNode( ini.GetChild(sSection) );
+}
+
 void PrefsManager::SavePrefsToDisk()
 {
 	IniFile ini;

stepmania/src/PrefsManager.h

@@ -249,6 +249,7 @@ public:
 
 	void ReadPrefsFromIni( const IniFile &ini, const CString &sSection );
 	void ReadGamePrefsFromIni( const CString &sIni );
+	void ReadDefaultsFromIni( const IniFile &ini, const CString &sSection );
 	void SavePrefsToIni( IniFile &ini );
 
 	void ReadPrefsFromDisk();
@@ -263,7 +264,7 @@ public:
 
 protected:
 	void ReadPrefsFromFile( const CString &sIni, const CString &sSection );
-
+	void ReadDefaultsFromFile( const CString &sIni, const CString &sSection );
 };