diff --git a/data/bg/defaultkeys.txt b/data/bg/defaultkeys.txt
index 6a6d7ed..c79f4b2 100644
--- a/data/bg/defaultkeys.txt
+++ b/data/bg/defaultkeys.txt
@@ -1,5 +1,7 @@
 # default key bindings

+Alt-KP+        scaleval_increase
+Alt-KP-    scaleval_decrease
 KP+        brighter
 KP-        darker
 Esc        close_or_menu
diff --git a/data/si/defaultkeys.txt b/data/si/defaultkeys.txt
index 7551be8..faf8fe6 100644
--- a/data/si/defaultkeys.txt
+++ b/data/si/defaultkeys.txt
@@ -1,5 +1,7 @@
 # default key bindings

+Alt-KP+        scaleval_increase
+Alt-KP-    scaleval_decrease
 KP+        brighter
 KP-        darker
 Esc        close_or_menu
diff --git a/exult.cc b/exult.cc
index 2519247..14944a8 100644
--- a/exult.cc
+++ b/exult.cc
@@ -209,6 +209,7 @@ struct resolution {
 };
 int num_res = sizeof(res_list) / sizeof(struct resolution);
 int current_res = 0;
+int current_scaleval = 1;

 #ifdef XWIN
 #  ifdef __GNUC__
@@ -242,6 +243,7 @@ static void Init();
 static int Play();
 static int Get_click(int &x, int &y, char *chr, bool drag_ok, Paintable *p, bool rotate_colors = false);
 static int find_resolution(int w, int h, int s);
+static void set_scaleval(int new_scaleval);
 #ifdef USE_EXULTSTUDIO
 static void Move_dragged_shape(int shape, int frame, int x, int y,
                                int prevx, int prevy, bool show);
@@ -2229,6 +2231,51 @@ int find_resolution(int w, int h, int s) {
    return res;
 }

+void increase_scaleval() {
+   if (!cheat()) return;
+
+   current_scaleval++;
+   if (current_scaleval >= 9)
+       current_scaleval = 1;
+   set_scaleval(current_scaleval);
+}
+
+void decrease_scaleval() {
+   if (!cheat()) return;
+
+   current_scaleval--;
+   if (current_scaleval < 1)
+       current_scaleval = 1;
+   set_scaleval(current_scaleval);
+}
+
+void set_scaleval(int new_scaleval) {
+   int scaler = gwin->get_win()->get_scaler();
+
+   if (new_scaleval >= 1 && scaler == Image_window::point && cheat.in_map_editor()) {
+       current_scaleval = new_scaleval;
+       bool fullscreen = gwin->get_win()->is_fullscreen();
+       bool share_settings;
+       config->value("config/video/share_video_settings", share_settings, true);
+       const string &vidStr = (fullscreen || share_settings) ?
+                              "config/video" : "config/video/window";
+       int gw, gh;
+       config->value(vidStr + "/game/width", gw);
+       config->value(vidStr + "/game/height", gh);
+       int resx, resy;
+       config->value(vidStr + "/display/width", resx);
+       config->value(vidStr + "/display/height", resy);
+
+       gwin->resized(resx,
+                     resy,
+                     fullscreen,
+                     gw, gh,
+                     current_scaleval, scaler,
+                     gwin->get_win()->get_fill_mode(),
+                     gwin->get_win()->get_fill_scaler());
+   }
+}
+
 void make_screenshot(bool silent) {
    // TODO: Maybe use <SAVEGAME>/exult%03i.pcx instead.
    // Or maybe some form or "My Pictures" on Windows.
diff --git a/exult.h b/exult.h
index f3c879d..969c97e 100644
--- a/exult.h
+++ b/exult.h
@@ -66,6 +66,8 @@ extern void Wait_for_arrival(
 );

 extern void change_gamma(bool down);
+extern void increase_scaleval();
+extern void decrease_scaleval();
 extern void setup_video(bool fullscreen, int setup_video_type,
                         int resx = 0, int resy = 0, int gw = 0,
                         int gh = 0, int scaleval = 0, int scaler = 0,
diff --git a/keyactions.cc b/keyactions.cc
index 9b4b4ec..ed113a2 100644
--- a/keyactions.cc
+++ b/keyactions.cc
@@ -247,6 +247,18 @@ void ActionRepaint(int const *params) {
    Game_window::get_instance()->paint();
 }

+//  { ActionScalevalIncrease, 0, "Increase scaleval", cheat_keys, NONE },
+void ActionScalevalIncrease(int const *params) {
+   ignore_unused_variable_warning(params);
+   increase_scaleval();
+}
+
+//  { ActionScalevalDecrease, 0, "Decrease scaleval", cheat_keys, NONE },
+void ActionScalevalDecrease(int const *params) {
+   ignore_unused_variable_warning(params);
+   decrease_scaleval();
+}
+
 //  { ActionBrighter, 0, "Increase brightness", normal_keys, NONE },
 void ActionBrighter(int const *params) {
    ignore_unused_variable_warning(params);
diff --git a/keyactions.h b/keyactions.h
index d275c24..beeb8d3 100644
--- a/keyactions.h
+++ b/keyactions.h
@@ -38,6 +38,8 @@ void ActionKeyboardMode(int const *params);

 void ActionScreenshot(int const *params);
 void ActionRepaint(int const *params);
+void ActionScalevalIncrease(int const *params);
+void ActionScalevalDecrease(int const *params);
 void ActionBrighter(int const *params);
 void ActionDarker(int const *params);
 void ActionFullscreen(int const *params);
diff --git a/keys.cc b/keys.cc
index df4799c..e2d4ce7 100644
--- a/keys.cc
+++ b/keys.cc
@@ -108,6 +108,14 @@ const struct Action {
 #endif

    {
+       "SCALEVAL_INCREASE",
+       ActionScalevalIncrease, 0, "Increase scaleval", Action::mapedit_keys, NONE, true, true, true, false
+   },
+   {
+       "SCALEVAL_DECREASE",
+       ActionScalevalDecrease, 0, "Decrease scaleval", Action::mapedit_keys, NONE, true, true, true, false
+   },
+   {
        "BRIGHTER",
        ActionBrighter, 0, "Increase brightness", Action::normal_keys, NONE, true, true, true, false
    },