use spatial index for whatever we can

OpenRA.Game/Orders/UnitOrderGenerator.cs

@@ -53,14 +53,13 @@ namespace OpenRA.Orders
 
 		string ChooseCursor(World world, MouseInput mi)
 		{
-
-			var p = Game.controller.MousePosition;
-			var c = Order(world, p.ToInt2(), mi)
-				.Select(o => CursorForOrderString(o.OrderString, o.Subject, o.TargetLocation))
-				.FirstOrDefault(a => a != null);
-
 			using (new PerfSample("cursor"))
 			{
+				var p = Game.controller.MousePosition;
+				var c = Order(world, p.ToInt2(), mi)
+					.Select(o => CursorForOrderString(o.OrderString, o.Subject, o.TargetLocation))
+					.FirstOrDefault(a => a != null);
+
 				return c ??
 					(world.SelectActorsInBox(Game.CellSize * p,
 					Game.CellSize * p).Any()

OpenRA.Game/WorldUtils.cs

@@ -82,13 +82,7 @@ namespace OpenRA
 
 		public static IEnumerable<Actor> FindUnits(this World world, float2 a, float2 b)
 		{
-			var min = float2.Min(a, b);
+			return world.WorldActor.traits.Get<SpatialBins>().ActorsInBox(a.ToInt2(), b.ToInt2());
-			var max = float2.Max(a, b);
-
-			var rect = new RectangleF(min.X, min.Y, max.X - min.X, max.Y - min.Y);
-
-			return world.Actors
-				.Where(x => x.GetBounds(true).IntersectsWith(rect));
 		}
 
 		public static IEnumerable<Actor> FindUnitsInCircle(this World world, float2 a, float r)

mods/cnc/system.yaml

@@ -221,4 +221,5 @@ World:
 		SilosNeeded: silos1.aud
 		UnitLost: unitlost.aud
 		NavalUnitLost: unitlost.aud
-		PrimaryBuildingSelected: pribldg1.aud
+		PrimaryBuildingSelected: pribldg1.aud
+	SpatialBins: