limited ammo support

OpenRa.Game/OpenRa.Game.csproj

@@ -181,6 +181,7 @@
     <Compile Include="Traits\Fake.cs" />
     <Compile Include="Traits\Harvester.cs" />
     <Compile Include="Traits\Helicopter.cs" />
+    <Compile Include="Traits\LimitedAmmo.cs" />
     <Compile Include="Traits\SquishByTank.cs" />
     <Compile Include="Traits\Plane.cs" />
     <Compile Include="Traits\ProductionQueue.cs" />

OpenRa.Game/Traits/AttackBase.cs

@@ -91,6 +91,11 @@ namespace OpenRa.Game.Traits
 		bool CheckFire(Actor self, Unit unit, string weaponName, ref int fireDelay, int[] offset, ref int burst)
 		{
 			if (fireDelay > 0) return false;
+
+			var limitedAmmo = self.traits.GetOrDefault<LimitedAmmo>();
+			if (!limitedAmmo.HasAmmo())
+				return false;
+
 			var weapon = Rules.WeaponInfo[weaponName];
 			if (weapon.Range * weapon.Range < (target.Location - self.Location).LengthSquared) return false;
 

OpenRa.Game/Traits/LimitedAmmo.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace OpenRa.Game.Traits
+{
+	class LimitedAmmo : INotifyAttack, IPips
+	{
+		int ammo;
+		Actor self;
+
+		public LimitedAmmo(Actor self)
+		{
+			ammo = self.Info.Ammo;
+			this.self = self;
+		}
+
+		public bool HasAmmo() { return ammo > 0; }
+
+		public void Attacking(Actor self) { --ammo; }
+
+		public IEnumerable<PipType> GetPips()
+		{
+			return Graphics.Util.MakeArray(self.Info.Ammo, 
+				i => ammo > i ? PipType.Green : PipType.Transparent);
+		}
+	}
+}