diff --git a/gfx.c b/gfx.c
--- a/gfx.c
+++ b/gfx.c
@@ -1,5 +1,6 @@
 #include "stdafx.h"
 #include "openttd.h"
+#include "functions.h"
 #include "player.h"
 #include "spritecache.h"
 #include "strings.h"