diff --git a/stepmania/src/LuaExpressionTransform.cpp b/stepmania/src/LuaExpressionTransform.cpp
index 66bd194df1..65e3b96bf2 100644
--- a/stepmania/src/LuaExpressionTransform.cpp
+++ b/stepmania/src/LuaExpressionTransform.cpp
@@ -15,6 +15,11 @@ LuaExpressionTransform::~LuaExpressionTransform()
 	delete m_pexprTransformFunction;
 }
 
+void LuaExpressionTransform::SetFromReference( const LuaReference &ref )
+{
+	*m_pexprTransformFunction = ref;
+}
+
 void LuaExpressionTransform::SetFromExpression( const RString &sExpression )
 {
 	m_pexprTransformFunction->SetFromExpression( sExpression );
diff --git a/stepmania/src/LuaExpressionTransform.h b/stepmania/src/LuaExpressionTransform.h
index 149015d36c..8815ce342e 100644
--- a/stepmania/src/LuaExpressionTransform.h
+++ b/stepmania/src/LuaExpressionTransform.h
@@ -13,6 +13,7 @@ public:
 	LuaExpressionTransform();
 	~LuaExpressionTransform();
 
+	void SetFromReference( const LuaReference &ref );
 	void SetFromExpression( const RString &sExpression );
 	void SetNumSubdivisions( int iNumSubdivisions ) { ASSERT( iNumSubdivisions > 0 ); m_iNumSubdivisions = iNumSubdivisions; }