diff --git a/src/mapper/map_func.cc b/src/mapper/map_func.cc
index b9f853b..f328b0a 100644
--- a/src/mapper/map_func.cc
+++ b/src/mapper/map_func.cc
@@ -1,6 +1,7 @@
 #include "mapper/map_func.h"
 
 #include "proto.h"
+#include "window_manager.h"
 
 namespace fallout {
 
@@ -19,6 +20,27 @@ void copy_proto_lists()
     // TODO: Incomplete.
 }
 
+// 0x4843A0
+void erase_rect(Rect* rect)
+{
+    Rect r = *rect;
+
+    r.bottom = rect->top;
+    windowRefreshAll(&r);
+
+    r.bottom = rect->bottom;
+    r.left = rect->right;
+    windowRefreshAll(&r);
+
+    r.left = rect->left;
+    r.top = rect->bottom;
+    windowRefreshAll(&r);
+
+    r.top = rect->top;
+    r.right = rect->left;
+    windowRefreshAll(&r);
+}
+
 // 0x484400
 int toolbar_proto(int type, int id)
 {
diff --git a/src/mapper/map_func.h b/src/mapper/map_func.h
index e779f28..0961c90 100644
--- a/src/mapper/map_func.h
+++ b/src/mapper/map_func.h
@@ -1,10 +1,13 @@
 #ifndef FALLOUT_MAPPER_MAP_FUNC_H_
 #define FALLOUT_MAPPER_MAP_FUNC_H_
 
+#include "geometry.h"
+
 namespace fallout {
 
 void setup_map_dirs();
 void copy_proto_lists();
+void erase_rect(Rect* rect);
 int toolbar_proto(int type, int id);
 bool map_toggle_block_obj_viewing_on();