diff --git a/src/strings_func.h b/src/strings_func.h
--- a/src/strings_func.h
+++ b/src/strings_func.h
@@ -222,6 +222,13 @@ public:
 	 */
 	virtual void Reset() = 0;
 
+	/**
+	 * Set the right font names.
+	 * @param settings  The settings to modify.
+	 * @param font_name The new font name.
+	 */
+	virtual void SetFontNames(struct FreeTypeSettings *settings, const char *font_name) = 0;
+
 	bool FindMissingGlyphs(const char **str);
 };