Merge pull request #10901 from pchote/server-maps

Remove Map usage from the server and mission browser.

OpenRA.Game/GameRules/Ruleset.cs

@@ -148,7 +148,9 @@ namespace OpenRA
 			return new Ruleset(dr.Actors, dr.Weapons, dr.Voices, dr.Notifications, dr.Music, ts, sequences);
 		}
 
-		public static Ruleset LoadFromMap(ModData modData, Map map)
+		public static Ruleset Load(ModData modData, IReadOnlyFileSystem fileSystem, string tileSet,
+			MiniYaml mapRules, MiniYaml mapWeapons, MiniYaml mapVoices, MiniYaml mapNotifications,
+			MiniYaml mapMusic, MiniYaml mapSequences)
 		{
 			var m = modData.Manifest;
 			var dr = modData.DefaultRules;
@@ -156,27 +158,27 @@ namespace OpenRA
 			Ruleset ruleset = null;
 			Action f = () =>
 			{
-				var actors = MergeOrDefault("Manifest,Rules", map, m.Rules, map.RuleDefinitions, dr.Actors,
+				var actors = MergeOrDefault("Rules", fileSystem, m.Rules, mapRules, dr.Actors,
 					k => new ActorInfo(modData.ObjectCreator, k.Key.ToLowerInvariant(), k.Value));
 
-				var weapons = MergeOrDefault("Manifest,Weapons", map, m.Weapons, map.WeaponDefinitions, dr.Weapons,
+				var weapons = MergeOrDefault("Weapons", fileSystem, m.Weapons, mapWeapons, dr.Weapons,
 					k => new WeaponInfo(k.Key.ToLowerInvariant(), k.Value));
 
-				var voices = MergeOrDefault("Manifest,Voices", map, m.Voices, map.VoiceDefinitions, dr.Voices,
+				var voices = MergeOrDefault("Voices", fileSystem, m.Voices, mapVoices, dr.Voices,
 					k => new SoundInfo(k.Value));
 
-				var notifications = MergeOrDefault("Manifest,Notifications", map, m.Notifications, map.NotificationDefinitions, dr.Notifications,
+				var notifications = MergeOrDefault("Notifications", fileSystem, m.Notifications, mapNotifications, dr.Notifications,
 					k => new SoundInfo(k.Value));
 
-				var music = MergeOrDefault("Manifest,Music", map, m.Music, map.NotificationDefinitions, dr.Music,
+				var music = MergeOrDefault("Music", fileSystem, m.Music, mapMusic, dr.Music,
 					k => new MusicInfo(k.Key, k.Value));
 
 				// TODO: Add support for merging custom tileset modifications
-				var ts = modData.DefaultTileSets[map.Tileset];
+				var ts = modData.DefaultTileSets[tileSet];
 
 				// TODO: Top-level dictionary should be moved into the Ruleset instead of in its own object
-				var sequences = map.SequenceDefinitions == null ? modData.DefaultSequences[map.Tileset] :
+				var sequences = mapSequences == null ? modData.DefaultSequences[tileSet] :
-					new SequenceProvider(map, modData, ts, map.SequenceDefinitions);
+					new SequenceProvider(fileSystem, modData, ts, mapSequences);
 
 				// TODO: Add support for custom voxel sequences
 				ruleset = new Ruleset(actors, weapons, voices, notifications, music, ts, sequences);

OpenRA.Game/Map/Map.cs

@@ -295,7 +295,8 @@ namespace OpenRA
 			{
 				try
 				{
-					return Ruleset.LoadFromMap(modData, this);
+					return Ruleset.Load(modData, this, Tileset, RuleDefinitions, WeaponDefinitions,
+						VoiceDefinitions, NotificationDefinitions, MusicDefinitions, SequenceDefinitions);
 				}
 				catch (Exception e)
 				{
@@ -1190,7 +1191,6 @@ namespace OpenRA
 			return FindTilesInAnnulus(center, 0, maxRange, allowOutsideBounds);
 		}
 
-		// Placeholders for future implementation
 		public Stream Open(string filename)
 		{
 			// Explicit package paths never refer to a map

OpenRA.Game/Map/MapCache.cs

@@ -25,7 +25,7 @@ namespace OpenRA
 {
 	public sealed class MapCache : IEnumerable<MapPreview>, IDisposable
 	{
-		public static readonly MapPreview UnknownMap = new MapPreview(null, MapGridType.Rectangular, null);
+		public static readonly MapPreview UnknownMap = new MapPreview(null, null, MapGridType.Rectangular, null);
 		public readonly IReadOnlyDictionary<IReadOnlyPackage, MapClassification> MapLocations;
 
 		readonly Cache<string, MapPreview> previews;
@@ -41,7 +41,7 @@ namespace OpenRA
 			this.modData = modData;
 
 			var gridType = Exts.Lazy(() => modData.Manifest.Get<MapGrid>().Type);
-			previews = new Cache<string, MapPreview>(uid => new MapPreview(uid, gridType.Value, this));
+			previews = new Cache<string, MapPreview>(uid => new MapPreview(modData, uid, gridType.Value, this));
 			sheetBuilder = new SheetBuilder(SheetType.BGRA);
 
 			// Enumerate map directories

OpenRA.Game/Map/MapPreview.cs

@@ -53,10 +53,11 @@ namespace OpenRA
 		public readonly bool downloading;
 	}
 
-	public class MapPreview : IDisposable
+	public class MapPreview : IDisposable, IReadOnlyFileSystem
 	{
 		static readonly CPos[] NoSpawns = new CPos[] { };
 		MapCache cache;
+		ModData modData;
 
 		public readonly string Uid;
 		public IReadOnlyPackage Package { get; private set; }
@@ -65,6 +66,8 @@ namespace OpenRA
 		public string Title { get; private set; }
 		public string Type { get; private set; }
 		public string Author { get; private set; }
+		public string TileSet { get; private set; }
+		public MapPlayers Players { get; private set; }
 		public int PlayerCount { get; private set; }
 		public CPos[] SpawnPoints { get; private set; }
 		public MapGridType GridType { get; private set; }
@@ -75,6 +78,10 @@ namespace OpenRA
 		public MapVisibility Visibility { get; private set; }
 		public bool SuitableForInitialMap { get; private set; }
 
+		Lazy<Ruleset> rules;
+		public Ruleset Rules { get { return rules != null ? rules.Value : null; } }
+		public bool InvalidCustomRules { get; private set; }
+
 		Download download;
 		public long DownloadBytes { get; private set; }
 		public int DownloadPercentage { get; private set; }
@@ -101,9 +108,11 @@ namespace OpenRA
 			generatingMinimap = false;
 		}
 
-		public MapPreview(string uid, MapGridType gridType, MapCache cache)
+		public MapPreview(ModData modData, string uid, MapGridType gridType, MapCache cache)
 		{
 			this.cache = cache;
+			this.modData = modData;
+
 			Uid = uid;
 			Title = "Unknown Map";
 			Type = "Unknown";
@@ -145,6 +154,8 @@ namespace OpenRA
 				Title = temp.Value;
 			if (yaml.TryGetValue("Type", out temp))
 				Type = temp.Value;
+			if (yaml.TryGetValue("Tileset", out temp))
+				TileSet = temp.Value;
 			if (yaml.TryGetValue("Author", out temp))
 				Author = temp.Value;
 			if (yaml.TryGetValue("Bounds", out temp))
@@ -188,9 +199,9 @@ namespace OpenRA
 				MiniYaml playerDefinitions;
 				if (yaml.TryGetValue("Players", out playerDefinitions))
 				{
-					var players = new MapPlayers(playerDefinitions.Nodes).Players;
+					Players = new MapPlayers(playerDefinitions.Nodes);
-					PlayerCount = players.Count(x => x.Value.Playable);
+					PlayerCount = Players.Players.Count(x => x.Value.Playable);
-					SuitableForInitialMap = EvaluateUserFriendliness(players);
+					SuitableForInitialMap = EvaluateUserFriendliness(Players.Players);
 				}
 			}
 			catch (Exception)
@@ -198,11 +209,41 @@ namespace OpenRA
 				Status = MapStatus.Unavailable;
 			}
 
+			rules = Exts.Lazy(() =>
+			{
+				try
+				{
+					var ruleDefinitions = LoadRuleSection(yaml, "Rules");
+					var weaponDefinitions = LoadRuleSection(yaml, "Weapons");
+					var voiceDefinitions = LoadRuleSection(yaml, "Voices");
+					var musicDefinitions = LoadRuleSection(yaml, "Music");
+					var notificationDefinitions = LoadRuleSection(yaml, "Notifications");
+					var sequenceDefinitions = LoadRuleSection(yaml, "Sequences");
+					return Ruleset.Load(modData, this, TileSet, ruleDefinitions, weaponDefinitions,
+						voiceDefinitions, notificationDefinitions, musicDefinitions, sequenceDefinitions);
+				}
+				catch
+				{
+					InvalidCustomRules = true;
+				}
+
+				return Ruleset.LoadDefaultsForTileSet(modData, TileSet);
+			});
+
 			if (p.Contains("map.png"))
 				using (var dataStream = p.GetStream("map.png"))
 					Preview = new Bitmap(dataStream);
 		}
 
+		MiniYaml LoadRuleSection(Dictionary<string, MiniYaml> yaml, string section)
+		{
+			MiniYaml node;
+			if (!yaml.TryGetValue(section, out node))
+				return null;
+
+			return node;
+		}
+
 		bool EvaluateUserFriendliness(Dictionary<string, PlayerReference> players)
 		{
 			if (Status != MapStatus.Available || !Visibility.HasFlag(MapVisibility.Lobby))
@@ -367,5 +408,42 @@ namespace OpenRA
 			if (deleteFromPackage != null)
 				deleteFromPackage.Delete(Package.Name);
 		}
+
+		Stream IReadOnlyFileSystem.Open(string filename)
+		{
+			// Explicit package paths never refer to a map
+			if (!filename.Contains("|") && Package.Contains(filename))
+				return Package.GetStream(filename);
+
+			return modData.DefaultFileSystem.Open(filename);
+		}
+
+		bool IReadOnlyFileSystem.TryGetPackageContaining(string path, out IReadOnlyPackage package, out string filename)
+		{
+			// Packages aren't supported inside maps
+			return modData.DefaultFileSystem.TryGetPackageContaining(path, out package, out filename);
+		}
+
+		bool IReadOnlyFileSystem.TryOpen(string filename, out Stream s)
+		{
+			// Explicit package paths never refer to a map
+			if (!filename.Contains("|"))
+			{
+				s = Package.GetStream(filename);
+				if (s != null)
+					return true;
+			}
+
+			return modData.DefaultFileSystem.TryOpen(filename, out s);
+		}
+
+		bool IReadOnlyFileSystem.Exists(string filename)
+		{
+			// Explicit package paths never refer to a map
+			if (!filename.Contains("|") && Package.Contains(filename))
+				return true;
+
+			return modData.DefaultFileSystem.Exists(filename);
+		}
 	}
 }

OpenRA.Game/Server/Server.cs

@@ -51,8 +51,7 @@ namespace OpenRA.Server
 		public List<string> TempBans = new List<string>();
 
 		// Managed by LobbyCommands
-		public Map Map;
+		public MapPreview Map;
-		public MapPlayers MapPlayers;
 
 		readonly int randomSeed;
 		readonly TcpListener listener;
@@ -323,7 +322,7 @@ namespace OpenRA.Server
 				}
 
 				if (client.Slot != null)
-					SyncClientToPlayerReference(client, MapPlayers.Players[client.Slot]);
+					SyncClientToPlayerReference(client, Map.Players.Players[client.Slot]);
 				else
 					client.Color = HSLColor.FromRGB(255, 255, 255);
 
@@ -392,12 +391,12 @@ namespace OpenRA.Server
 						SendOrderTo(newConn, "Message", motd);
 				}
 
-				if (Map.RuleDefinitions != null && !LobbyInfo.IsSinglePlayer)
+				if (Map.Rules != ModData.DefaultRules && !LobbyInfo.IsSinglePlayer)
 					SendOrderTo(newConn, "Message", "This map contains custom rules. Game experience may change.");
 
 				if (Settings.DisableSinglePlayer)
 					SendOrderTo(newConn, "Message", "Singleplayer games have been disabled on this server.");
-				else if (MapPlayers.Players.Where(p => p.Value.Playable).All(p => !p.Value.AllowBots))
+				else if (Map.Players.Players.Where(p => p.Value.Playable).All(p => !p.Value.AllowBots))
 					SendOrderTo(newConn, "Message", "Bots have been disabled on this map.");
 
 				if (handshake.Mod == "{DEV_VERSION}")

OpenRA.Mods.Common/ServerTraits/LobbyCommands.cs

@@ -152,7 +152,7 @@ namespace OpenRA.Mods.Common.Server
 							client.SpawnPoint = 0;
 
 						client.Slot = s;
-						S.SyncClientToPlayerReference(client, server.MapPlayers.Players[s]);
+						S.SyncClientToPlayerReference(client, server.Map.Players.Players[s]);
 
 						if (!slot.LockColor)
 							client.PreferredColor = client.Color = SanitizePlayerColor(server, client.Color, client.Index, conn);
@@ -311,7 +311,7 @@ namespace OpenRA.Mods.Common.Server
 							var tileset = server.Map.Rules.TileSet;
 							var terrainColors = tileset.TerrainInfo.Where(ti => ti.RestrictPlayerColor).Select(ti => ti.Color);
 							var playerColors = server.LobbyInfo.Clients.Select(c => c.Color.RGB)
-								.Concat(server.MapPlayers.Players.Values.Select(p => p.Color.RGB));
+								.Concat(server.Map.Players.Players.Values.Select(p => p.Color.RGB));
 							bot.Color = bot.PreferredColor = validator.RandomValidColor(server.Random, terrainColors, playerColors);
 
 							server.LobbyInfo.Clients.Add(bot);
@@ -323,7 +323,7 @@ namespace OpenRA.Mods.Common.Server
 							bot.Bot = botType;
 						}
 
-						S.SyncClientToPlayerReference(bot, server.MapPlayers.Players[parts[0]]);
+						S.SyncClientToPlayerReference(bot, server.Map.Players.Players[parts[0]]);
 						server.SyncLobbyClients();
 						server.SyncLobbySlots();
 						return true;
@@ -370,9 +370,9 @@ namespace OpenRA.Mods.Common.Server
 							if (c.Slot != null)
 							{
 								// Remove Bot from slot if slot forbids bots
-								if (c.Bot != null && !server.MapPlayers.Players[c.Slot].AllowBots)
+								if (c.Bot != null && !server.Map.Players.Players[c.Slot].AllowBots)
 									server.LobbyInfo.Clients.Remove(c);
-								S.SyncClientToPlayerReference(c, server.MapPlayers.Players[c.Slot]);
+								S.SyncClientToPlayerReference(c, server.Map.Players.Players[c.Slot]);
 							}
 							else if (c.Bot != null)
 								server.LobbyInfo.Clients.Remove(c);
@@ -387,12 +387,12 @@ namespace OpenRA.Mods.Common.Server
 
 						server.SendMessage("{0} changed the map to {1}.".F(client.Name, server.Map.Title));
 
-						if (server.Map.RuleDefinitions != null)
+						if (server.Map.Rules.Actors != server.ModData.DefaultRules.Actors)
 							server.SendMessage("This map contains custom rules. Game experience may change.");
 
 						if (server.Settings.DisableSinglePlayer)
 							server.SendMessage("Singleplayer games have been disabled on this server.");
-						else if (server.MapPlayers.Players.Where(p => p.Value.Playable).All(p => !p.Value.AllowBots))
+						else if (server.Map.Players.Players.Where(p => p.Value.Playable).All(p => !p.Value.AllowBots))
 							server.SendMessage("Bots have been disabled on this map.");
 
 						return true;
@@ -875,7 +875,7 @@ namespace OpenRA.Mods.Common.Server
 
 						int spawnPoint;
 						if (!Exts.TryParseIntegerInvariant(parts[1], out spawnPoint)
-							|| spawnPoint < 0 || spawnPoint > server.Map.SpawnPoints.Value.Length)
+							|| spawnPoint < 0 || spawnPoint > server.Map.SpawnPoints.Length)
 						{
 							Log.Write("server", "Invalid spawn point: {0}", parts[1]);
 							return true;
@@ -1013,28 +1013,28 @@ namespace OpenRA.Mods.Common.Server
 			};
 		}
 
-		public static void LoadMapSettings(Session.Global gs, Map map)
+		public static void LoadMapSettings(Session.Global gs, Ruleset rules)
 		{
-			var devMode = map.Rules.Actors["player"].TraitInfo<DeveloperModeInfo>();
+			var devMode = rules.Actors["player"].TraitInfo<DeveloperModeInfo>();
 			gs.AllowCheats = devMode.Enabled;
 
-			var crateSpawner = map.Rules.Actors["world"].TraitInfoOrDefault<CrateSpawnerInfo>();
+			var crateSpawner = rules.Actors["world"].TraitInfoOrDefault<CrateSpawnerInfo>();
 			gs.Crates = crateSpawner != null && crateSpawner.Enabled;
 
-			var shroud = map.Rules.Actors["player"].TraitInfo<ShroudInfo>();
+			var shroud = rules.Actors["player"].TraitInfo<ShroudInfo>();
 			gs.Fog = shroud.FogEnabled;
 			gs.Shroud = !shroud.ExploredMapEnabled;
 
-			var resources = map.Rules.Actors["player"].TraitInfo<PlayerResourcesInfo>();
+			var resources = rules.Actors["player"].TraitInfo<PlayerResourcesInfo>();
 			gs.StartingCash = resources.DefaultCash;
 
-			var startingUnits = map.Rules.Actors["world"].TraitInfoOrDefault<SpawnMPUnitsInfo>();
+			var startingUnits = rules.Actors["world"].TraitInfoOrDefault<SpawnMPUnitsInfo>();
 			gs.StartingUnitsClass = startingUnits == null ? "none" : startingUnits.StartingUnitsClass;
 
-			var mapBuildRadius = map.Rules.Actors["world"].TraitInfoOrDefault<MapBuildRadiusInfo>();
+			var mapBuildRadius = rules.Actors["world"].TraitInfoOrDefault<MapBuildRadiusInfo>();
 			gs.AllyBuildRadius = mapBuildRadius != null && mapBuildRadius.AllyBuildRadiusEnabled;
 
-			var mapOptions = map.Rules.Actors["world"].TraitInfo<MapOptionsInfo>();
+			var mapOptions = rules.Actors["world"].TraitInfo<MapOptionsInfo>();
 			gs.ShortGame = mapOptions.ShortGameEnabled;
 			gs.TechLevel = mapOptions.TechLevel;
 			gs.Difficulty = mapOptions.Difficulty ?? mapOptions.Difficulties.FirstOrDefault();
@@ -1042,15 +1042,14 @@ namespace OpenRA.Mods.Common.Server
 
 		static void LoadMap(S server)
 		{
-			server.Map = new Map(server.ModData, server.ModData.MapCache[server.LobbyInfo.GlobalSettings.Map].Package);
+			server.Map = server.ModData.MapCache[server.LobbyInfo.GlobalSettings.Map];
 
-			server.MapPlayers = new MapPlayers(server.Map.PlayerDefinitions);
+			server.LobbyInfo.Slots = server.Map.Players.Players
-			server.LobbyInfo.Slots = server.MapPlayers.Players
 				.Select(p => MakeSlotFromPlayerReference(p.Value))
 				.Where(s => s != null)
 				.ToDictionary(s => s.PlayerReference, s => s);
 
-			LoadMapSettings(server.LobbyInfo.GlobalSettings, server.Map);
+			LoadMapSettings(server.LobbyInfo.GlobalSettings, server.Map.Rules);
 		}
 
 		static HSLColor SanitizePlayerColor(S server, HSLColor askedColor, int playerIndex, Connection connectionToEcho = null)
@@ -1067,7 +1066,7 @@ namespace OpenRA.Mods.Common.Server
 			var tileset = server.Map.Rules.TileSet;
 			var terrainColors = tileset.TerrainInfo.Where(ti => ti.RestrictPlayerColor).Select(ti => ti.Color).ToList();
 			var playerColors = server.LobbyInfo.Clients.Where(c => c.Index != playerIndex).Select(c => c.Color.RGB)
-				.Concat(server.MapPlayers.Players.Values.Select(p => p.Color.RGB)).ToList();
+				.Concat(server.Map.Players.Players.Values.Select(p => p.Color.RGB)).ToList();
 
 			return validator.MakeValid(askColor.RGB, server.Random, terrainColors, playerColors, onError);
 		}
@@ -1086,7 +1085,7 @@ namespace OpenRA.Mods.Common.Server
 			if (slot == null)
 				return null;
 
-			return server.MapPlayers.Players[slot.PlayerReference];
+			return server.Map.Players.Players[slot.PlayerReference];
 		}
 	}
 }

OpenRA.Mods.Common/ServerTraits/LobbySettingsNotification.cs

@@ -24,7 +24,7 @@ namespace OpenRA.Mods.Common.Server
 				return;
 
 			var defaults = new Session.Global();
-			LobbyCommands.LoadMapSettings(defaults, server.Map);
+			LobbyCommands.LoadMapSettings(defaults, server.Map.Rules);
 
 			if (server.LobbyInfo.GlobalSettings.AllowCheats != defaults.AllowCheats)
 				server.SendOrderTo(conn, "Message", "Allow Cheats: {0}".F(server.LobbyInfo.GlobalSettings.AllowCheats));

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

@@ -43,11 +43,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 		readonly ScrollPanelWidget missionList;
 		readonly ScrollItemWidget headerTemplate;
 		readonly ScrollItemWidget template;
-		readonly Cache<MapPreview, Map> mapCache;
-
-		MapPreview selectedMapPreview;
-		Map selectedMap;
 
+		MapPreview selectedMap;
 		PlayingVideo playingVideo;
 
 		string difficulty;
@@ -56,7 +53,6 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 		[ObjectCreator.UseCtor]
 		public MissionBrowserLogic(Widget widget, ModData modData, World world, Action onStart, Action onExit)
 		{
-			mapCache = new Cache<MapPreview, Map>(p => new Map(modData, p.Package));
 			this.modData = modData;
 			this.onStart = onStart;
 
@@ -67,12 +63,12 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 
 			var title = widget.GetOrNull<LabelWidget>("MISSIONBROWSER_TITLE");
 			if (title != null)
-				title.GetText = () => playingVideo != PlayingVideo.None ? selectedMapPreview.Title : title.Text;
+				title.GetText = () => playingVideo != PlayingVideo.None ? selectedMap.Title : title.Text;
 
-			widget.Get("MISSION_INFO").IsVisible = () => selectedMapPreview != null;
+			widget.Get("MISSION_INFO").IsVisible = () => selectedMap != null;
 
 			var previewWidget = widget.Get<MapPreviewWidget>("MISSION_PREVIEW");
-			previewWidget.Preview = () => selectedMapPreview;
+			previewWidget.Preview = () => selectedMap;
 			previewWidget.IsVisible = () => playingVideo == PlayingVideo.None;
 
 			videoPlayer = widget.Get<VqaPlayerWidget>("MISSION_VIDEO");
@@ -132,11 +128,14 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			if (allPreviews.Any())
 				SelectMap(allPreviews.First());
 
-			// Preload map and preview data to reduce jank
+			// Preload map preview and rules to reduce jank
 			new Thread(() =>
 			{
 				foreach (var p in allPreviews)
-					modData.MapCache[mapCache[p].Uid].GetMinimap();
+				{
+					p.GetMinimap();
+					var unused = p.Rules;
+				}
 			}).Start();
 
 			var startButton = widget.Get<ButtonWidget>("STARTGAME_BUTTON");
@@ -163,7 +162,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				var preview = p;
 
 				var item = ScrollItemWidget.Setup(template,
-					() => selectedMapPreview != null && selectedMapPreview.Uid == preview.Uid,
+					() => selectedMap != null && selectedMap.Uid == preview.Uid,
 					() => SelectMap(preview),
 					StartMissionClicked);
 
@@ -174,8 +173,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 
 		void SelectMap(MapPreview preview)
 		{
-			selectedMap = mapCache[preview];
+			selectedMap = preview;
-			selectedMapPreview = preview;
 
 			// Cache the rules on a background thread to avoid jank
 			var difficultyDisabled = true;
@@ -189,17 +187,15 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var infoVideoVisible = false;
 			var infoVideoDisabled = true;
 
-			var map = selectedMap;
 			new Thread(() =>
 			{
-				map.PreloadRules();
+				var mapOptions = preview.Rules.Actors["world"].TraitInfo<MapOptionsInfo>();
-				var mapOptions = map.Rules.Actors["world"].TraitInfo<MapOptionsInfo>();
 
 				difficulty = mapOptions.Difficulty ?? mapOptions.Difficulties.FirstOrDefault();
 				difficulties = mapOptions.Difficulties;
 				difficultyDisabled = mapOptions.DifficultyLocked || mapOptions.Difficulties.Length <= 1;
 
-				var missionData = map.Rules.Actors["world"].TraitInfoOrDefault<MissionDataInfo>();
+				var missionData = preview.Rules.Actors["world"].TraitInfoOrDefault<MissionDataInfo>();
 				if (missionData != null)
 				{
 					briefingVideo = missionData.BriefingVideo;
@@ -214,7 +210,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					var height = descriptionFont.Measure(briefing).Y;
 					Game.RunAfterTick(() =>
 					{
-						if (map == selectedMap)
+						if (preview == selectedMap)
 						{
 							description.Text = briefing;
 							description.Bounds.Height = height;
@@ -348,11 +344,11 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				PlayVideo(fsPlayer, missionData.StartVideo, PlayingVideo.GameStart, () =>
 				{
 					StopVideo(fsPlayer);
-					Game.CreateAndStartLocalServer(selectedMapPreview.Uid, orders, onStart);
+					Game.CreateAndStartLocalServer(selectedMap.Uid, orders, onStart);
 				});
 			}
 			else
-				Game.CreateAndStartLocalServer(selectedMapPreview.Uid, orders, onStart);
+				Game.CreateAndStartLocalServer(selectedMap.Uid, orders, onStart);
 		}
 
 		class DropDownOption