added a new hotkey to trigger pixel doubling

closes #5122

OpenRA.Game/Settings.cs

@@ -169,6 +169,8 @@ namespace OpenRA
 
 		public Hotkey ObserverCombinedView = new Hotkey(Keycode.MINUS, Modifiers.None);
 		public Hotkey ObserverWorldView = new Hotkey(Keycode.EQUALS, Modifiers.None);
+
+		public Hotkey TogglePixelDoubleKey = new Hotkey(Keycode.PERIOD, Modifiers.None);
 	}
 
 	public class IrcSettings

OpenRA.Mods.RA/Widgets/Logic/SettingsLogic.cs

@@ -271,6 +271,7 @@ namespace OpenRA.Mods.RA.Widgets.Logic
 				{ "CycleProductionBuildingsKey", "Cycle production facilities" },
 
 				{ "ToggleStatusBarsKey", "Toggle status bars" },
+				{ "TogglePixelDoubleKey", "Toggle pixel doubling" },
 			};
 
 			var unitHotkeys = new Dictionary<string, string>()

OpenRA.Mods.RA/Widgets/WorldCommandWidget.cs

@@ -65,6 +65,9 @@ namespace OpenRA.Mods.RA.Widgets
 				if (key == ks.ToggleStatusBarsKey)
 					return ToggleStatusBars();
 
+				if (key == ks.TogglePixelDoubleKey)
+					return TogglePixelDouble();
+
 				// Put all functions that aren't unit-specific before this line!
 				if (!world.Selection.Actors.Any())
 					return false;
@@ -253,5 +256,12 @@ namespace OpenRA.Mods.RA.Widgets
 			Game.Settings.Game.AlwaysShowStatusBars ^= true;
 			return true;
 		}
+
+		bool TogglePixelDouble()
+		{
+			Game.Settings.Graphics.PixelDouble ^= true;
+			worldRenderer.Viewport.Zoom = Game.Settings.Graphics.PixelDouble ? 2 : 1;
+			return true;
+		}
 	}
 }