#1050 Extract generic PlayMusicOnMapLoad trait from cnc shellmap script

OpenRA.Mods.RA/World/PlayMusicOnMapLoad.cs

@@ -0,0 +1,45 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2011 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. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using OpenRA.FileFormats;
+using OpenRA.Traits;
+using OpenRA.Widgets;
+
+namespace OpenRA.Mods.RA
+{
+	class PlayMusicOnMapLoadInfo : ITraitInfo
+	{
+		public readonly string Music = null;
+		public readonly bool Loop = false;
+
+		public object Create(ActorInitializer init) { return new PlayMusicOnMapLoad(this); }
+	}
+
+	class PlayMusicOnMapLoad : IWorldLoaded
+	{
+		PlayMusicOnMapLoadInfo Info;
+
+		public PlayMusicOnMapLoad(PlayMusicOnMapLoadInfo info) { Info = info; }
+
+		public void WorldLoaded(World w) { PlayMusic(); }
+
+		void PlayMusic()
+		{
+			var onComplete = Info.Loop ? (Action)PlayMusic : () => {};
+
+			if (Game.Settings.Game.ShellmapMusic &&
+			    Rules.Music.ContainsKey(Info.Music))
+				Sound.PlayMusicThen(Rules.Music[Info.Music], onComplete);
+		}
+	}
+}
+