diff --git a/source/games/duke/src/game_main.cpp b/source/games/duke/src/game_main.cpp
index bc55a4b94..b5364d9ae 100644
--- a/source/games/duke/src/game_main.cpp
+++ b/source/games/duke/src/game_main.cpp
@@ -565,13 +565,14 @@ void drawoverheadmap(int cposx, int cposy, int czoom, int cang)
 // calculate size of 3D viewport.
 // Fixme: this needs to be adjusted to the new status bar code, 
 // once the status bar is a persistent queriable object
+// (it should also be moved out of the game code then.
 //
 //---------------------------------------------------------------------------
 
 void updateviewport(void)
 {
 	ud.screen_size = clamp(ud.screen_size, 0, 64);
-	const int32_t ss = std::max(ud.screen_size - 8, 0);
+	int ss = std::max(ud.screen_size - 8, 0);
 
 	int x1 = scale(ss, xdim, 160);
 	int x2 = xdim - x1;
diff --git a/source/games/duke/src/premap.h b/source/games/duke/src/premap.h
index 4802706de..157a32941 100644
--- a/source/games/duke/src/premap.h
+++ b/source/games/duke/src/premap.h
@@ -34,7 +34,7 @@ int G_FindLevelByFile(const char *fileName);
 void G_CacheMapData(void);
 void G_NewGame(int volumeNum, int levelNum, int skillNum);
 void G_ResetTimers(uint8_t keepgtics);
-void G_UpdateScreenArea(void);
+void updateviewport(void);
 void pickrandomspot(int playerNum);
 void resetinventory(int playerNum);
 void P_ResetPlayer(int playerNum);
@@ -43,7 +43,6 @@ void resetweapons(int playerNum);
 void resetprestat(int snum, int g);
 void G_ClearFIFO(void);
 void G_ResetInterpolations(void);
-extern int32_t fragbarheight(void);
 void setmapfog(int fogtype);
 void G_InitRRRASkies(void);
 void prelevel_common(int g);
diff --git a/source/games/duke/src/zz_game.cpp b/source/games/duke/src/zz_game.cpp
index fe4cc57a8..0747345f8 100644
--- a/source/games/duke/src/zz_game.cpp
+++ b/source/games/duke/src/zz_game.cpp
@@ -1219,14 +1219,14 @@ void GameInterface::set_hud_layout(int layout)
 		ud.screen_size = RR? screen_size_vals_rr[layout] : screen_size_vals[layout];
 		ud.statusbarmode = layout >= 8;
 		ud.althud = layout >= 10;
-		G_UpdateScreenArea();
+		updateviewport();
 	}
 }
 
 void GameInterface::set_hud_scale(int scale)
 {
     ud.statusbarscale = clamp(scale, 36, 100);
-    G_UpdateScreenArea();
+    updateviewport();
 }
 
 void G_HandleLocalKeys(void)
@@ -1257,7 +1257,7 @@ void G_HandleLocalKeys(void)
                 hud_scale = hud_scale + 4;
             }
 
-            G_UpdateScreenArea();
+            updateviewport();
         }
 
         if (buttonMap.ButtonDown(gamefunc_Shrink_Screen))
@@ -1276,7 +1276,7 @@ void G_HandleLocalKeys(void)
                 hud_scale = hud_scale - 4;
             }
 
-            G_UpdateScreenArea();
+            updateviewport();
         }
     }
 
@@ -1394,7 +1394,7 @@ void G_HandleLocalKeys(void)
         ud.last_overhead = ud.overhead_on;
         ud.overhead_on   = 0;
         ud.scrollmode    = 0;
-        G_UpdateScreenArea();
+        updateviewport();
     }
 #endif
 
@@ -1414,7 +1414,7 @@ void G_HandleLocalKeys(void)
         }
 
         restorepalette = 1;
-        G_UpdateScreenArea();
+        updateviewport();
     }
 }
 
@@ -1631,7 +1631,7 @@ static int G_EndOfLevel(void)
         {
             int32_t i = ud.screen_size;
             ud.screen_size = 0;
-            G_UpdateScreenArea();
+            updateviewport();
             ud.screen_size = i;
 
             G_BonusScreen(0);
@@ -1968,7 +1968,7 @@ MAIN_LOOP_RESTART:
             goto MAIN_LOOP_RESTART;
         }
     }
-    else G_UpdateScreenArea();
+    else updateviewport();
 
 //    G_GameExit(" "); ///
 
@@ -2217,7 +2217,7 @@ void GameInterface::FreeGameData()
 
 void GameInterface::UpdateScreenSize()
 {
-    G_UpdateScreenArea();
+    updateviewport();
 }
 
 ::GameInterface* CreateInterface()
diff --git a/source/games/duke/src/zz_premap.cpp b/source/games/duke/src/zz_premap.cpp
index c3fdbdc02..467d214fb 100644
--- a/source/games/duke/src/zz_premap.cpp
+++ b/source/games/duke/src/zz_premap.cpp
@@ -384,8 +384,8 @@ int G_EnterLevel(int gameMode)
 
     /*
     G_DoLoadScreen(msg, -1);
-    G_UpdateScreenArea();
     */
+    updateviewport();
     int res = LoadTheMap(mi, pPlayer, gameMode);
     if (res != 0) return res;
 
@@ -482,7 +482,7 @@ int G_EnterLevel(int gameMode)
 
     restorepalette = -1;
 
-    G_UpdateScreenArea();
+    updateviewport();
     videoClearViewableArea(0L);
     drawbackground();
     G_DrawRooms(myconnectindex,65536);