diff --git a/doomsday/engine/portable/src/p_objlink.c b/doomsday/engine/portable/src/p_objlink.c
index e6976ca263..b20ebfdcb3 100644
--- a/doomsday/engine/portable/src/p_objlink.c
+++ b/doomsday/engine/portable/src/p_objlink.c
@@ -342,7 +342,7 @@ static void processSeg(seg_t* seg, void* data)
         // Don't spread if the middle material completely fills the gap between
         // floor and ceiling (direction is from dest to source).
         if(Rend_DoesMidTextureFillGap(seg->lineDef,
-            dest == seg->backSeg->subsector? BACK : FRONT))
+            dest == seg->backSeg->subsector? false : true))
             return;
     }