diff --git a/sim/fakes/sys_display.py b/sim/fakes/sys_display.py
index 3e2b94417d7345898b0cd449da57f02ae6b51115..84897e7f0e5ca54fb00616888f444a2586874c1b 100644
--- a/sim/fakes/sys_display.py
+++ b/sim/fakes/sys_display.py
@@ -5,7 +5,7 @@ def pipe_full():
     return False
 
 
-def set_overlay_height(foo):
+def overlay_clip(x0, y0, x1, y1):
     pass