Add unit guarding

OpenRA.Mods.RA/Guard.cs

@@ -0,0 +1,98 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2013 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 System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using OpenRA.Graphics;
+using OpenRA.Mods.RA.Activities;
+using OpenRA.Mods.RA.Move;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.RA
+{
+	class GuardInfo : TraitInfo<Guard>, Requires<MobileInfo> { }
+
+	class Guard : IResolveOrder, IOrderVoice
+	{
+		public void ResolveOrder(Actor self, Order order)
+		{
+			if (order.OrderString == "Guard")
+			{
+				var target = Target.FromActor(order.TargetActor);
+				self.SetTargetLine(target, Color.Yellow);
+				self.QueueActivity(false, new AttackMove.AttackMoveActivity(self,
+					new Follow(target, target.Actor.Info.Traits.Get<GuardableInfo>().Range)));
+			}
+		}
+
+		public string VoicePhraseForOrder(Actor self, Order order)
+		{
+			return order.OrderString == "Guard" ? "Move" : null;
+		}
+	}
+
+	class GuardOrderGenerator : IOrderGenerator
+	{
+		readonly IEnumerable<Actor> subjects;
+
+		public GuardOrderGenerator(IEnumerable<Actor> subjects)
+		{
+			this.subjects = subjects;
+		}
+
+		public IEnumerable<Order> Order(World world, CPos xy, MouseInput mi)
+		{
+			if (mi.Button == Game.mouseButtonPreference.Cancel)
+			{
+				world.CancelInputMode();
+				yield break;
+			}
+
+			var target = FriendlyGuardableUnitsAtMouse(world, mi).FirstOrDefault();
+
+			if (target == null || subjects.All(s => s.IsDead()))
+				yield break;
+
+			foreach (var actor in subjects)
+				yield return new Order("Guard", actor, false) { TargetActor = target };
+		}
+
+		public void Tick(World world)
+		{
+			if (subjects.All(s => s.IsDead() || !s.HasTrait<Guard>()))
+				world.CancelInputMode();
+		}
+
+		public void RenderBeforeWorld(WorldRenderer wr, World world) { }
+		public void RenderAfterWorld(WorldRenderer wr, World world) { }
+
+		public string GetCursor(World world, CPos xy, MouseInput mi)
+		{
+			return world.Map.IsInMap(xy)
+				&& FriendlyGuardableUnitsAtMouse(world, mi).Any()
+				? "guard"
+				: "move-blocked";
+		}
+
+		static IEnumerable<Actor> FriendlyGuardableUnitsAtMouse(World world, MouseInput mi)
+		{
+			return world.FindUnitsAtMouse(mi.Location)
+				.Where(a => !a.IsDead() && a.AppearsFriendlyTo(world.LocalPlayer.PlayerActor) && a.HasTrait<Guardable>());
+		}
+	}
+
+	class GuardableInfo : TraitInfo<Guardable>
+	{
+		public readonly int Range = 2;
+	}
+
+	class Guardable { }
+}