Dispose actors when tearing down the world.

OpenRA.Game/Actor.cs

@@ -22,7 +22,7 @@ using OpenRA.Traits;
 
 namespace OpenRA
 {
-	public class Actor : IScriptBindable, IScriptNotifyBind, ILuaTableBinding, ILuaEqualityBinding, ILuaToStringBinding, IEquatable<Actor>
+	public sealed class Actor : IScriptBindable, IScriptNotifyBind, ILuaTableBinding, ILuaEqualityBinding, ILuaToStringBinding, IEquatable<Actor>, IDisposable
 	{
 		public readonly ActorInfo Info;
 

OpenRA.Game/Graphics/WorldRenderer.cs

@@ -123,6 +123,9 @@ namespace OpenRA.Graphics
 
 		public void Draw()
 		{
+			if (World.WorldActor.Disposed)
+				return;
+
 			RefreshPalette();
 
 			if (World.Type == WorldType.Shellmap && !Game.Settings.Game.ShowShellmap)
@@ -273,6 +276,12 @@ namespace OpenRA.Graphics
 
 		public void Dispose()
 		{
+			// HACK: Disposing the world from here violates ownership
+			// but the WorldRenderer lifetime matches the disposal
+			// behavior we want for the world, and the root object setup
+			// is so horrible that doing it properly would be a giant mess.
+			World.Dispose();
+
 			palette.Dispose();
 			Theater.Dispose();
 			terrainRenderer.Dispose();

OpenRA.Game/World.cs

@@ -24,7 +24,7 @@ namespace OpenRA
 {
 	public enum WorldType { Regular, Shellmap, Editor }
 
-	public class World
+	public sealed class World : IDisposable
 	{
 		class ActorIDComparer : IComparer<Actor>
 		{
@@ -369,6 +369,19 @@ namespace OpenRA
 				pi.OutcomeTimestampUtc = DateTime.UtcNow;
 			}
 		}
+
+		public void Dispose()
+		{
+			frameEndActions.Clear();
+
+			// Dispose newer actors first, and the world actor last
+			foreach (var a in actors.Reverse())
+				a.Dispose();
+
+			// Actor disposals are done in a FrameEndTask
+			while (frameEndActions.Count != 0)
+				frameEndActions.Dequeue()(this);
+		}
 	}
 
 	public struct TraitPair<T>