diff --git a/newgrf.h b/newgrf.h
--- a/newgrf.h
+++ b/newgrf.h
@@ -12,6 +12,7 @@ struct GRFFile {
 	uint32 grfid;
 	uint16 flags;
 	uint16 sprite_offset;
+	SpriteID first_spriteset; ///< Holds the first spriteset's sprite offset.
 	GRFFile *next;
 
 	/* A sprite group contains all sprites of a given vehicle (or multiple