Add FirstNonEmptyBounds method for IDecorationBounds interface.

This provides a more efficient way of determining the bounds by avoiding LINQ. A helper that works directly on arrays prevents allocation of an enumerator when the collection is know to be an array.

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -110,6 +110,34 @@ namespace OpenRA.Traits
 	// HACK: This provides a shim for legacy code until it can be rewritten
 	public interface IDecorationBounds { Rectangle DecorationBounds(Actor self, WorldRenderer wr); }
 	public interface IDecorationBoundsInfo : ITraitInfoInterface { }
+	public static class DecorationBoundsExtensions
+	{
+		public static Rectangle FirstNonEmptyBounds(this IEnumerable<IDecorationBounds> decorationBounds, Actor self, WorldRenderer wr)
+		{
+			// PERF: Avoid LINQ.
+			foreach (var decoration in decorationBounds)
+			{
+				var bounds = decoration.DecorationBounds(self, wr);
+				if (!bounds.IsEmpty)
+					return bounds;
+			}
+
+			return Rectangle.Empty;
+		}
+
+		public static Rectangle FirstNonEmptyBounds(this IDecorationBounds[] decorationBounds, Actor self, WorldRenderer wr)
+		{
+			// PERF: Avoid LINQ.
+			foreach (var decoration in decorationBounds)
+			{
+				var bounds = decoration.DecorationBounds(self, wr);
+				if (!bounds.IsEmpty)
+					return bounds;
+			}
+
+			return Rectangle.Empty;
+		}
+	}
 
 	public interface IIssueOrder
 	{

OpenRA.Mods.Cnc/Traits/SupportPowers/ChronoshiftPower.cs

@@ -163,10 +163,7 @@ namespace OpenRA.Mods.Cnc.Traits
 				{
 					if (unit.CanBeViewedByPlayer(manager.Self.Owner))
 					{
-						var bounds = unit.TraitsImplementing<IDecorationBounds>()
+						var bounds = unit.TraitsImplementing<IDecorationBounds>().FirstNonEmptyBounds(unit, wr);
-							.Select(b => b.DecorationBounds(unit, wr))
-							.FirstOrDefault(b => !b.IsEmpty);
-
 						yield return new SelectionBoxRenderable(unit, bounds, Color.Red);
 					}
 				}
@@ -281,10 +278,7 @@ namespace OpenRA.Mods.Cnc.Traits
 				{
 					if (unit.CanBeViewedByPlayer(manager.Self.Owner))
 					{
-						var bounds = unit.TraitsImplementing<IDecorationBounds>()
+						var bounds = unit.TraitsImplementing<IDecorationBounds>().FirstNonEmptyBounds(unit, wr);
-							.Select(b => b.DecorationBounds(unit, wr))
-							.FirstOrDefault(b => !b.IsEmpty);
-
 						yield return new SelectionBoxRenderable(unit, bounds, Color.Red);
 					}
 				}

OpenRA.Mods.Common/Traits/Render/RenderNameTag.cs

@@ -50,7 +50,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 
 		public IEnumerable<IRenderable> Render(Actor self, WorldRenderer wr)
 		{
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 			var spaceBuffer = (int)(10 / wr.Viewport.Zoom);
 			var effectPos = wr.ProjectedPosition(new int2((bounds.Left + bounds.Right) / 2, bounds.Y - spaceBuffer));
 

OpenRA.Mods.Common/Traits/Render/SelectionDecorations.cs

@@ -89,7 +89,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			var selected = self.World.Selection.Contains(self);
 			var regularWorld = self.World.Type == WorldType.Regular;
 			var statusBars = Game.Settings.Game.StatusBars;
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 
 			// Health bars are shown when:
 			//  * actor is selected

OpenRA.Mods.Common/Traits/Render/WithDecoration.cs

@@ -106,7 +106,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			if (!ShouldRender(self) || self.World.FogObscures(self))
 				return Enumerable.Empty<IRenderable>();
 
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 			var halfSize = (0.5f * Anim.Image.Size.XY).ToInt2();
 
 			var boundsOffset = new int2(bounds.Left + bounds.Right, bounds.Top + bounds.Bottom) / 2;

OpenRA.Mods.Common/Traits/Render/WithSpriteControlGroupDecoration.cs

@@ -72,7 +72,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 
 			pipImages.PlayFetchIndex(Info.GroupSequence, () => (int)group);
 
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 			var boundsOffset = 0.5f * new float2(bounds.Left + bounds.Right, bounds.Top + bounds.Bottom);
 			if (Info.ReferencePoint.HasFlag(ReferencePoints.Top))
 				boundsOffset -= new float2(0, 0.5f * bounds.Height);

OpenRA.Mods.Common/Traits/Render/WithTextControlGroupDecoration.cs

@@ -87,7 +87,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			if (group == null)
 				yield break;
 
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 			var number = group.Value.ToString();
 			var halfSize = font.Measure(number) / 2;
 

OpenRA.Mods.Common/Traits/Render/WithTextDecoration.cs

@@ -105,7 +105,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			if (!ShouldRender(self) || self.World.FogObscures(self))
 				return Enumerable.Empty<IRenderable>();
 
-			var bounds = decorationBounds.Select(b => b.DecorationBounds(self, wr)).FirstOrDefault(b => !b.IsEmpty);
+			var bounds = decorationBounds.FirstNonEmptyBounds(self, wr);
 			var halfSize = font.Measure(Info.Text) / 2;
 
 			var boundsOffset = new int2(bounds.Left + bounds.Right, bounds.Top + bounds.Bottom) / 2;

OpenRA.Mods.Common/Traits/SupportPowers/GrantExternalConditionPower.cs

@@ -138,9 +138,7 @@ namespace OpenRA.Mods.Common.Traits
 				var xy = wr.Viewport.ViewToWorld(Viewport.LastMousePos);
 				foreach (var unit in power.UnitsInRange(xy))
 				{
-					var bounds = unit.TraitsImplementing<IDecorationBounds>()
+					var bounds = unit.TraitsImplementing<IDecorationBounds>().FirstNonEmptyBounds(unit, wr);
-						.Select(b => b.DecorationBounds(unit, wr))
-						.FirstOrDefault(b => !b.IsEmpty);
 					yield return new SelectionBoxRenderable(unit, bounds, Color.Red);
 				}
 			}

OpenRA.Mods.Common/Widgets/WorldInteractionControllerWidget.cs

@@ -51,10 +51,7 @@ namespace OpenRA.Mods.Common.Widgets
 			// TODO: Integrate this with SelectionDecorations to unhardcode the *Renderable
 			if (unit.Info.HasTraitInfo<SelectableInfo>())
 			{
-				var bounds = unit.TraitsImplementing<IDecorationBounds>()
+				var bounds = unit.TraitsImplementing<IDecorationBounds>().FirstNonEmptyBounds(unit, worldRenderer);
-					.Select(b => b.DecorationBounds(unit, worldRenderer))
-					.FirstOrDefault(b => !b.IsEmpty);
-
 				new SelectionBarsRenderable(unit, bounds, true, true).Render(worldRenderer);
 			}
 		}