allow Lua expressions in text metrics by prepending @

stepmania/src/ActorUtil.cpp

@@ -6,10 +6,7 @@
 #include "BGAnimation.h"
 #include "IniFile.h"
 #include "ThemeManager.h"
-#include "RageDisplay.h"
 #include "RageLog.h"
-#include "arch/ArchHooks/ArchHooks.h"
-#include "RageFileManager.h"
 #include "SongCreditDisplay.h"
 #include "song.h"
 #include "GameState.h"
@@ -76,13 +73,8 @@ Actor* LoadFromActorFile( const CString& sAniDir, const XNode& layer )
 		CString sAlttext;
 		layer.GetAttrValue("AltText", sAlttext );
 
-		// Keep the special treatment of text string sync'd with the same treatments
-		// in ThemeManager.
-		sText.Replace( "::", "\n" );
-		sAlttext.Replace( "::", "\n" );
-
-		FontCharAliases::ReplaceMarkers( sText );
-		FontCharAliases::ReplaceMarkers( sAlttext );
+		ThemeManager::EvaluateString( sText );
+		ThemeManager::EvaluateString( sAlttext );
 
 		BitmapText* pBitmapText = new BitmapText;
 

stepmania/src/LuaHelpers.cpp

@@ -241,6 +241,22 @@ float Lua::RunExpressionF( const CString &str )
 	return result;
 }
 
+bool Lua::RunExpressionS( const CString &str, CString &sOut )
+{
+	if( L == NULL )
+		OpenLua();
+
+	if( !RunExpression( str ) )
+		return false;
+
+	ASSERT( lua_gettop(L) > 0 );
+
+	sOut = lua_tostring( L, -1 );
+	lua_pop( L, -1 );
+
+	return true;
+}
+
 void Lua::Fail( lua_State *L, const CString &err )
 {
 	lua_pushstring( L, err );

stepmania/src/LuaHelpers.h

@@ -7,6 +7,7 @@ namespace Lua
 	void PrepareExpression( CString &sInOut );	// strip "//" comments and "+"
 	bool RunExpressionB( const CString &str );
 	float RunExpressionF( const CString &str );
+	bool RunExpressionS( const CString &str, CString &sOut );
 
 	void Fail( lua_State *L, const CString &err );
 

stepmania/src/ThemeManager.cpp

@@ -650,16 +650,34 @@ CString ThemeManager::GetMetric( const CString &sClassName, const CString &sValu
 {
 	CString sValue = GetMetricRaw(sClassName,sValueName);
 
-	// "::" means newline since you can't use line breaks in an ini file.
-	sValue.Replace("::","\n");
-
-	/* XXX: add a parameter to turn this off if there are some metrics where
-	 * we don't want markers */
-	FontCharAliases::ReplaceMarkers(sValue);
+	EvaluateString( sValue );
 
 	return sValue;
 }
 
+void ThemeManager::EvaluateString( CString &sText )
+{
+	/* If the string begins with an @, treat it as a raw Lua expression, and don't do any
+	 * other filtering.  (XXX: maybe we should still do font aliases) */
+	if( sText.size() >= 1 && sText[0] == '@' )
+	{
+		/* Erase "@". */
+		sText.erase( 0, 1 );
+
+		CString sOut;
+		Lua::RunExpressionS( sText, sOut );
+		LOG->Trace("ran '%s', got '%s'", sText.c_str(), sOut.c_str());
+		sText = sOut;
+		return;
+	}
+
+	// "::" means newline since you can't use line breaks in an ini file.
+	// XXX: this makes it impossible to put a colon at the end of a line, eg: "Color:\nRed"
+	sText.Replace("::","\n");
+
+	FontCharAliases::ReplaceMarkers( sText );
+}
+
 int ThemeManager::GetMetricI( const CString &sClassName, const CString &sValueName )
 {
 	return atoi( GetMetricRaw(sClassName,sValueName) );

stepmania/src/ThemeManager.h

@@ -35,6 +35,8 @@ public:
 	void ReloadMetrics();
 	void GetModifierNames( set<CString>& AddTo );
 
+	static void EvaluateString( CString &sText );
+
 	/* I renamed these for two reasons.  The overload conflicts with the ones below:
 	 * GetPathToB( str, str ) was matching the ones below instead of these.  It's also
 	 * easier to search for uses of obsolete functions if they have a different name. */