First step in the attack mechanism's refactor.

Enabled firing multiple armaments at a target simultaneously.
Each armament defines own cursor for targeting.
The force attack modifier influences armament choice for target.
Autotargeting modified to handle firing multiple armaments simultaneously.
As a consequence, healers (medics) no longer require separate Heal
activity and AttackMedic and AutoHeal traits.

OpenRA.Mods.Common/Activities/Attack.cs

@@ -8,6 +8,7 @@
  */
 #endregion
 
+using System.Linq;
 using OpenRA.Activities;
 using OpenRA.Mods.Common.Traits;
 using OpenRA.Traits;
@@ -21,15 +22,17 @@ namespace OpenRA.Mods.Common.Activities
 		readonly AttackBase attack;
 		readonly IMove move;
 		readonly IFacing facing;
-		readonly Armament armament;
-		readonly WDist minRange;
 		readonly IPositionable positionable;
+		readonly bool forceAttack;
 
-		public Attack(Actor self, Target target, Armament armament, bool allowMovement)
+		WDist minRange;
+		WDist maxRange;
+
+		public Attack(Actor self, Target target, bool allowMovement, bool forceAttack)
 		{
 			Target = target;
-			this.minRange = armament.Weapon.MinRange;
-			this.armament = armament;
+
+			this.forceAttack = forceAttack;
 
 			attack = self.Trait<AttackBase>();
 			facing = self.Trait<IFacing>();
@@ -64,8 +67,16 @@ namespace OpenRA.Mods.Common.Activities
 			if (!attack.Info.IgnoresVisibility && type == TargetType.Actor && !Target.Actor.Info.HasTraitInfo<FrozenUnderFogInfo>() && !self.Owner.CanTargetActor(Target.Actor))
 				return NextActivity;
 
+			// Drop the target once none of the weapons are effective against it
+			var armaments = attack.ChooseArmamentsForTarget(Target, forceAttack);
+			if (!armaments.Any())
+				return NextActivity;
+
+			// Update ranges
+			minRange = armaments.Max(a => a.Weapon.MinRange);
+			maxRange = armaments.Min(a => a.MaxRange());
+
 			// Try to move within range
-			var maxRange = armament.MaxRange();
 			if (move != null && (!Target.IsInRange(self.CenterPosition, maxRange) || Target.IsInRange(self.CenterPosition, minRange)))
 				return Util.SequenceActivities(move.MoveWithinRange(Target, minRange, maxRange), this);
 
@@ -73,7 +84,7 @@ namespace OpenRA.Mods.Common.Activities
 			if (facing.Facing != desiredFacing)
 				return Util.SequenceActivities(new Turn(self, desiredFacing), this);
 
-			attack.DoAttack(self, Target);
+			attack.DoAttack(self, Target, armaments);
 
 			return this;
 		}

OpenRA.Mods.Common/Activities/Heal.cs

@@ -1,33 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright 2007-2015 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 OpenRA.Activities;
-using OpenRA.Mods.Common.Traits;
-using OpenRA.Traits;
-
-namespace OpenRA.Mods.Common.Activities
-{
-	public class Heal : Attack
-	{
-		public Heal(Actor self, Target target, Armament armament, bool allowMovement)
-			: base(self, target, armament, allowMovement) { }
-
-		protected override Activity InnerTick(Actor self, AttackBase attack)
-		{
-			if (!Target.IsValidFor(self) || !self.Owner.IsAlliedWith(Target.Actor.Owner))
-				return NextActivity;
-
-			if (Target.Type == TargetType.Actor && Target.Actor.GetDamageState() == DamageState.Undamaged)
-				return NextActivity;
-
-			return base.InnerTick(self, attack);
-		}
-	}
-}

OpenRA.Mods.Common/Activities/Move/AttackMoveActivity.cs

@@ -33,7 +33,7 @@ namespace OpenRA.Mods.Common.Activities
 		{
 			if (autoTarget != null && --scanTicks <= 0)
 			{
-				autoTarget.ScanAndAttack(self);
+				autoTarget.ScanAndAttack(self, true);
 				scanTicks = ScanInterval;
 			}