Add an ICreationActivity interface

OpenRA.Game/Actor.cs

@@ -82,6 +82,7 @@ namespace OpenRA
 		readonly INotifyIdle[] tickIdles;
 		readonly ITargetablePositions[] targetablePositions;
 		WPos[] staticTargetablePositions;
+		bool created;
 
 		internal Actor(World world, string name, TypeDictionary initDict)
 		{
@@ -138,6 +139,35 @@ namespace OpenRA
 			SyncHashes = TraitsImplementing<ISync>().Select(sync => new SyncHash(sync)).ToArray();
 		}
 
+		internal void Created()
+		{
+			created = true;
+
+			foreach (var t in TraitsImplementing<INotifyCreated>())
+				t.Created(this);
+
+			// The initial activity should run before any activities queued by INotifyCreated.Created
+			// However, we need to know which traits are enabled (via conditions), so wait for after the calls and insert the activity as the first
+			ICreationActivity creationActivity = null;
+			foreach (var ica in TraitsImplementing<ICreationActivity>())
+			{
+				if (!ica.IsTraitEnabled())
+					continue;
+
+				if (creationActivity != null)
+					throw new InvalidOperationException("More than one enabled ICreationActivity trait: {0} and {1}".F(creationActivity.GetType().Name, ica.GetType().Name));
+
+				var activity = ica.GetCreationActivity();
+				if (activity == null)
+					continue;
+
+				creationActivity = ica;
+
+				activity.Queue(CurrentActivity);
+				CurrentActivity = activity;
+			}
+		}
+
 		public void Tick()
 		{
 			var wasIdle = IsIdle;
@@ -214,11 +244,15 @@ namespace OpenRA
 		{
 			if (!queued)
 				CancelActivity();
+
 			QueueActivity(nextActivity);
 		}
 
 		public void QueueActivity(Activity nextActivity)
 		{
+			if (!created)
+				throw new InvalidOperationException("An activity was queued before the actor was created. Queue it inside the INotifyCreated.Created callback instead.");
+
 			if (CurrentActivity == null)
 				CurrentActivity = nextActivity;
 			else

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -12,6 +12,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using OpenRA.Activities;
 using OpenRA.FileSystem;
 using OpenRA.Graphics;
 using OpenRA.Network;
@@ -538,4 +539,7 @@ namespace OpenRA.Traits
 
 	[RequireExplicitImplementation]
 	public interface IUnlocksRenderPlayer { bool RenderPlayerUnlocked { get; } }
+
+	[RequireExplicitImplementation]
+	public interface ICreationActivity { Activity GetCreationActivity(); }
 }

OpenRA.Game/World.cs

@@ -330,10 +330,10 @@ namespace OpenRA
 		public Actor CreateActor(bool addToWorld, string name, TypeDictionary initDict)
 		{
 			var a = new Actor(this, name, initDict);
-			foreach (var t in a.TraitsImplementing<INotifyCreated>())
+			a.Created();
-				t.Created(a);
 			if (addToWorld)
 				Add(a);
+
 			return a;
 		}
 

OpenRA.Mods.Common/Traits/Air/Aircraft.cs

@@ -190,7 +190,7 @@ namespace OpenRA.Mods.Common.Traits
 
 	public class Aircraft : ITick, ISync, IFacing, IPositionable, IMove, IIssueOrder, IResolveOrder, IOrderVoice, IDeathActorInitModifier,
 		INotifyCreated, INotifyAddedToWorld, INotifyRemovedFromWorld, INotifyActorDisposing, INotifyBecomingIdle,
-		IActorPreviewInitModifier, IIssueDeployOrder, IObservesVariables
+		IActorPreviewInitModifier, IIssueDeployOrder, IObservesVariables, ICreationActivity
 	{
 		static readonly Pair<CPos, SubCell>[] NoCells = { };
 
@@ -309,8 +309,6 @@ namespace OpenRA.Mods.Common.Traits
 			notifyMoving = self.TraitsImplementing<INotifyMoving>().ToArray();
 			positionOffsets = self.TraitsImplementing<IAircraftCenterPositionOffset>().ToArray();
 			overrideAircraftLanding = self.TraitOrDefault<IOverrideAircraftLanding>();
-
-			self.QueueActivity(MoveIntoWorld(self, moveIntoWorldDelay));
 		}
 
 		void INotifyAddedToWorld.AddedToWorld(Actor self)
@@ -1164,6 +1162,11 @@ namespace OpenRA.Mods.Common.Traits
 				inits.Add(new DynamicFacingInit(() => Facing));
 		}
 
+		Activity ICreationActivity.GetCreationActivity()
+		{
+			return MoveIntoWorld(self, moveIntoWorldDelay);
+		}
+
 		public class AircraftMoveOrderTargeter : IOrderTargeter
 		{
 			readonly Aircraft aircraft;

OpenRA.Mods.Common/Traits/Harvester.cs

@@ -130,8 +130,6 @@ namespace OpenRA.Mods.Common.Traits
 			mobile = self.Trait<Mobile>();
 			resLayer = self.World.WorldActor.Trait<ResourceLayer>();
 			claimLayer = self.World.WorldActor.Trait<ResourceClaimLayer>();
-
-			self.QueueActivity(new CallFunc(() => ChooseNewProc(self, null)));
 		}
 
 		void INotifyCreated.Created(Actor self)
@@ -141,6 +139,8 @@ namespace OpenRA.Mods.Common.Traits
 			conditionManager = self.TraitOrDefault<ConditionManager>();
 			UpdateCondition(self);
 
+			self.QueueActivity(new CallFunc(() => ChooseNewProc(self, null)));
+
 			// Note: This is queued in a FrameEndTask because otherwise the activity is dropped/overridden while moving out of a factory.
 			if (Info.SearchOnCreation)
 				self.World.AddFrameEndTask(w => self.QueueActivity(new FindAndDeliverResources(self)));

OpenRA.Mods.Common/Traits/Mobile.cs

@@ -138,7 +138,7 @@ namespace OpenRA.Mods.Common.Traits
 		}
 	}
 
-	public class Mobile : PausableConditionalTrait<MobileInfo>, IIssueOrder, IResolveOrder, IOrderVoice, IPositionable, IMove, ITick,
+	public class Mobile : PausableConditionalTrait<MobileInfo>, IIssueOrder, IResolveOrder, IOrderVoice, IPositionable, IMove, ITick, ICreationActivity,
 		IFacing, IDeathActorInitModifier, INotifyAddedToWorld, INotifyRemovedFromWorld, INotifyBlockingMove, IActorPreviewInitModifier, INotifyBecomingIdle
 	{
 		readonly Actor self;
@@ -256,7 +256,6 @@ namespace OpenRA.Mods.Common.Traits
 			Locomotor = self.World.WorldActor.TraitsImplementing<Locomotor>()
 				.Single(l => l.Info.Name == Info.Locomotor);
 
-			self.QueueActivity(MoveIntoWorld(self, moveIntoWorldDelay));
 			base.Created(self);
 		}
 
@@ -897,6 +896,11 @@ namespace OpenRA.Mods.Common.Traits
 			}
 		}
 
+		Activity ICreationActivity.GetCreationActivity()
+		{
+			return MoveIntoWorld(self, moveIntoWorldDelay);
+		}
+
 		class MoveOrderTargeter : IOrderTargeter
 		{
 			readonly Mobile mobile;