push the check-synchash-doesn't-change pattern into a utility fn. furthur reduce the number of uses on Game.world

OpenRA.Game/Game.cs

@@ -47,7 +47,6 @@ namespace OpenRA
 			var map = modData.PrepareMap(uid);
 			
 			viewport = new Viewport(new float2(Renderer.Resolution), map.TopLeft, map.BottomRight, Renderer);
-			world = null;	// trying to access the old world will NRE, rather than silently doing it wrong.
 			world = new World(modData.Manifest, map);
 		}
 
@@ -101,7 +100,7 @@ namespace OpenRA
 		static ConnectionState lastConnectionState = ConnectionState.PreConnecting;
 		public static int LocalClientId { get { return orderManager.Connection.LocalClientId; } }
 
-		static void Tick()
+		static void Tick( World world, OrderManager orderManager, Viewport viewPort )
 		{
 			if (orderManager.Connection.ConnectionState != lastConnectionState)
 			{
@@ -159,7 +158,7 @@ namespace OpenRA
 
 		internal static event Action LobbyInfoChanged = () => { };
 
-		internal static void SyncLobbyInfo(string data)
+		internal static void SyncLobbyInfo( World world, string data)
 		{
 			LobbyInfo = Session.Deserialize(data);
 
@@ -186,6 +185,7 @@ namespace OpenRA
 		public static event Action BeforeGameStart = () => {};
 		internal static void StartGame(string map)
 		{
+			world = null;
 			BeforeGameStart();
 			LoadMap(map);
 			if (orderManager.GameStarted) return;
@@ -200,23 +200,20 @@ namespace OpenRA
 
 		public static void DispatchMouseInput(MouseInputEvent ev, MouseEventArgs e, Modifiers modifierKeys)
 		{
-			if (world == null)
-				return;
+			var world = Game.world;
+			if (world == null) return;
 
-			int sync = world.SyncHash();
-			var initialWorld = world;
-
-			var mi = new MouseInput
+			Sync.CheckSyncUnchanged( world, () =>
 			{
-				Button = (MouseButton)(int)e.Button,
-				Event = ev,
-				Location = new int2(e.Location),
-				Modifiers = modifierKeys,
-			};
-			Widget.HandleInput(world, mi);
-
-			if (sync != world.SyncHash() && world == initialWorld)
-				throw new InvalidOperationException("Desync in DispatchMouseInput");
+				var mi = new MouseInput
+				{
+					Button = (MouseButton)(int)e.Button,
+					Event = ev,
+					Location = new int2( e.Location ),
+					Modifiers = modifierKeys,
+				};
+				Widget.HandleInput( world, mi );
+			} );
 		}
 
 		public static bool IsHost
@@ -231,16 +228,13 @@ namespace OpenRA
 
 		public static void HandleKeyEvent(KeyInput e)
 		{
-			if (world == null)
-				return;
+			var world = Game.world;
+			if( world == null ) return;
 
-			int sync = world.SyncHash();
-
-			if (Widget.HandleKeyPress(e))
-				return;
-
-			if (sync != Game.world.SyncHash())
-				throw new InvalidOperationException("Desync in OnKeyPress");
+			Sync.CheckSyncUnchanged( world, () =>
+			{
+				Widget.HandleKeyPress( e );
+			} );
 		}
 
 		static Modifiers modifiers;
@@ -324,7 +318,7 @@ namespace OpenRA
 		internal static void Run()
 		{
 			while (!quit)
-			{
+			{
 				Tick( world, orderManager, viewport );
 				Application.DoEvents();
 			}

OpenRA.Game/Graphics/WorldRenderer.cs

@@ -97,8 +97,8 @@ namespace OpenRA.Graphics
 			if (world.OrderGenerator != null)
 				world.OrderGenerator.RenderBeforeWorld(world);
 
-			foreach (var image in worldSprites)
-				image.Sprite.DrawAt(image.Pos, image.Palette);
+			foreach( var image in worldSprites )
+				image.Sprite.DrawAt( image.Pos, this.GetPaletteIndex( image.Palette ) );
 			uiOverlay.Draw(world);
 
 			if (world.OrderGenerator != null)

OpenRA.Game/Network/UnitOrders.cs

@@ -78,7 +78,7 @@ namespace OpenRA.Network
 				}
 			case "SyncInfo":
 				{
-					Game.SyncLobbyInfo(order.TargetString);
+					Game.SyncLobbyInfo( world, order.TargetString);
 					break;
 				}
 			case "SetStance":

OpenRA.Game/Sync.cs

@@ -129,5 +129,22 @@ namespace OpenRA
 				return p.Index * 0x567;
 			return 0;
 		}
+
+		public static void CheckSyncUnchanged( World world, Action fn )
+		{
+			int sync = world.SyncHash();
+			fn();
+			if( sync != world.SyncHash() )
+				throw new InvalidOperationException( "Desync in DispatchMouseInput" );
+		}
+
+		public static T CheckSyncUnchanged<T>( World world, Func<T> fn )
+		{
+			int sync = world.SyncHash();
+			var ret = fn();
+			if( sync != world.SyncHash() )
+				throw new InvalidOperationException( "Desync in DispatchMouseInput" );
+			return ret;
+		}
 	}
 }

OpenRA.Game/Widgets/WorldInteractionControllerWidget.cs

@@ -109,8 +109,7 @@ namespace OpenRA.Widgets
 		public override string GetCursor(int2 pos)
 		{
 			var world = Game.world;
-			int sync = world.SyncHash();
-			try
+			return Sync.CheckSyncUnchanged( world, () =>
 			{
 				if (!world.GameHasStarted)
 					return "default";
@@ -122,13 +121,8 @@ namespace OpenRA.Widgets
 					Modifiers = Game.GetModifierKeys()
 				};
 
-				return Game.world.OrderGenerator.GetCursor( world, Game.viewport.ViewToWorld(mi).ToInt2(), mi );
-			}
-			finally
-			{
-				if( sync != world.SyncHash() )
-					throw new InvalidOperationException( "Desync in InputControllerWidget.GetCursor" );
-			}
+				return world.OrderGenerator.GetCursor( world, Game.viewport.ViewToWorld(mi).ToInt2(), mi );
+			} );
 		}
 
 		public override bool HandleKeyPressInner(KeyInput e)

OpenRA.Mods.RA/Widgets/MoneyBinWidget.cs

@@ -35,6 +35,8 @@ namespace OpenRA.Mods.RA.Widgets
 
 		public override void DrawInner(World world)
 		{
+			if( world.LocalPlayer == null ) return;
+
 			var playerResources = world.LocalPlayer.PlayerActor.Trait<PlayerResources>();
 
 			var digitCollection = "digits-" + world.LocalPlayer.Country.Race;

OpenRA.Mods.RA/Widgets/PowerBinWidget.cs

@@ -27,6 +27,8 @@ namespace OpenRA.Mods.RA.Widgets
 
 		public override void DrawInner(World world)
 		{
+			if( world.LocalPlayer == null ) return;
+
 			powerCollection = "power-" + world.LocalPlayer.Country.Race;
 
 			var power = world.LocalPlayer.PlayerActor.Trait<PowerManager>();

OpenRA.Mods.RA/Widgets/RadarBinWidget.cs

@@ -121,6 +121,8 @@ namespace OpenRA.Mods.RA.Widgets
 
 		public override void DrawInner(World world)
 		{
+			if( world.LocalPlayer == null ) return;
+
 			radarCollection = "radar-" + world.LocalPlayer.Country.Race;
 
 			Game.Renderer.RgbaSpriteRenderer.DrawSprite(ChromeProvider.GetImage(radarCollection, "left"), radarOrigin);

OpenRA.Mods.RA/Widgets/SpecialPowerBinWidget.cs

@@ -68,6 +68,8 @@ namespace OpenRA.Mods.RA.Widgets
 		{		
 			buttons.Clear();
 
+			if( world.LocalPlayer == null ) return;
+			
 			var powers = world.LocalPlayer.PlayerActor.TraitsImplementing<SupportPower>();
 			var numPowers = powers.Count(p => p.IsAvailable);
 			if (numPowers == 0) return;