diff --git a/OpenRA.Game/Graphics/Renderable.cs b/OpenRA.Game/Graphics/Renderable.cs
index e0290eeef1..d7e3f08792 100644
--- a/OpenRA.Game/Graphics/Renderable.cs
+++ b/OpenRA.Game/Graphics/Renderable.cs
@@ -14,22 +14,6 @@ using System.Linq;
 
 namespace OpenRA.Graphics
 {
-	public class RenderableComparer : IComparer<IRenderable>
-	{
-		WorldRenderer wr;
-		public RenderableComparer(WorldRenderer wr)
-		{
-			this.wr = wr;
-		}
-
-		public int Compare(IRenderable x, IRenderable y)
-		{
-			var xOrder = wr.ScreenZPosition(x.Pos, x.ZOffset);
-			var yOrder = wr.ScreenZPosition(y.Pos, y.ZOffset);
-			return xOrder.CompareTo(yOrder);
-		}
-	}
-
 	public interface IRenderable
 	{
 		WPos Pos { get; }
diff --git a/OpenRA.Game/Graphics/WorldRenderer.cs b/OpenRA.Game/Graphics/WorldRenderer.cs
index 072adf1635..7442affaec 100644
--- a/OpenRA.Game/Graphics/WorldRenderer.cs
+++ b/OpenRA.Game/Graphics/WorldRenderer.cs
@@ -31,6 +31,9 @@ namespace OpenRA.Graphics
 
 	public sealed class WorldRenderer : IDisposable
 	{
+		public static readonly Func<IRenderable, int> RenderableScreenZPositionComparisonKey =
+			r => ZPosition(r.Pos, r.ZOffset);
+
 		public readonly World World;
 		public readonly Theater Theater;
 		public Viewport Viewport { get; private set; }
@@ -69,7 +72,6 @@ namespace OpenRA.Graphics
 
 		List<IRenderable> GenerateRenderables()
 		{
-			var comparer = new RenderableComparer(this);
 			var actors = World.ScreenMap.ActorsInBox(Viewport.TopLeft, Viewport.BottomRight)
 				.Append(World.WorldActor)
 				.ToList();
@@ -82,7 +84,7 @@ namespace OpenRA.Graphics
 			if (World.OrderGenerator != null)
 				worldRenderables = worldRenderables.Concat(World.OrderGenerator.Render(this, World));
 
-			worldRenderables = worldRenderables.OrderBy(r => r, comparer);
+			worldRenderables = worldRenderables.OrderBy(RenderableScreenZPositionComparisonKey);
 
 			// Effects are drawn on top of all actors
 			// HACK: Effects aren't interleaved with actors.
@@ -241,7 +243,12 @@ namespace OpenRA.Graphics
 		public float ScreenZPosition(WPos pos, int offset)
 		{
 			var ts = Game.ModData.Manifest.TileSize;
-			return (pos.Y + pos.Z + offset) * ts.Height / 1024f;
+			return ZPosition(pos, offset) * ts.Height / 1024f;
+		}
+
+		static int ZPosition(WPos pos, int offset)
+		{
+			return pos.Y + pos.Z + offset;
 		}
 
 		public WPos Position(int2 screenPx)
diff --git a/OpenRA.Mods.RA/Orders/PlaceBuildingOrderGenerator.cs b/OpenRA.Mods.RA/Orders/PlaceBuildingOrderGenerator.cs
index 62dc072dc7..0ae8124769 100644
--- a/OpenRA.Mods.RA/Orders/PlaceBuildingOrderGenerator.cs
+++ b/OpenRA.Mods.RA/Orders/PlaceBuildingOrderGenerator.cs
@@ -127,11 +127,10 @@ namespace OpenRA.Mods.RA.Orders
 					initialized = true;
 				}
 
-				var comparer = new RenderableComparer(wr);
 				var offset = world.Map.CenterOfCell(topLeft) + FootprintUtils.CenterOffset(world, buildingInfo);
 				var previewRenderables = preview
 					.SelectMany(p => p.Render(wr, offset))
-					.OrderBy(r => r, comparer);
+					.OrderBy(WorldRenderer.RenderableScreenZPositionComparisonKey);
 
 				foreach (var r in previewRenderables)
 					yield return r;