Add visual indicator when the game is muted.

OpenRA.Mods.Common/Widgets/Logic/MuteIndicatorLogic.cs

@@ -0,0 +1,25 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using OpenRA.Widgets;
+
+namespace OpenRA.Mods.Common.Widgets.Logic
+{
+	public class MuteIndicatorLogic : ChromeLogic
+	{
+		[ObjectCreator.UseCtor]
+		public MuteIndicatorLogic(Widget widget)
+		{
+			var gs = Game.Settings.Sound;
+			widget.IsVisible = () => gs.Mute;
+		}
+	}
+}