Rework decoration renderable traits:

- Removed implicit pip definitions and IPips interface.
  New decoration traits have been added to render them.
  Pip types are no longer hardcoded in OpenRA.Game.

- Decoration rendering is now managed by SelectionDecorations(Base),
  which allows us to remove assumptions about the selection box
  geometry from the decoration traits.

- RenderNameTag has been replaced by WithNameTagDecoration, which is
  an otherwise normal decoration trait.

- Unify the configuration and reduce duplication between traits.

- Removed hardcoded references to specific selection box renderables.

- Remove legacy cruft.

OpenRA.Game/Primitives/Rectangle.cs

@@ -66,6 +66,11 @@ namespace OpenRA.Primitives
 		public int2 Location { get { return new int2(X, Y); } }
 		public Size Size { get { return new Size(Width, Height); } }
 
+		public int2 TopLeft { get { return Location; } }
+		public int2 TopRight { get { return new int2(X + Width, Y); } }
+		public int2 BottomLeft { get { return new int2(X, Y + Height); } }
+		public int2 BottomRight { get { return new int2(X + Width, Y + Height); } }
+
 		public bool Contains(int x, int y)
 		{
 			return x >= Left && x < Right && y >= Top && y < Bottom;

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -66,9 +66,6 @@ namespace OpenRA.Traits
 		void Kill(Actor self, Actor attacker, BitSet<DamageType> damageTypes);
 	}
 
-	// depends on the order of pips in WorldRenderer.cs!
-	public enum PipType { Transparent, Green, Yellow, Red, Gray, Blue, Ammo, AmmoEmpty }
-
 	[Flags]
 	public enum Stance
 	{
@@ -128,38 +125,6 @@ namespace OpenRA.Traits
 	public interface IMouseBoundsInfo : ITraitInfoInterface { }
 	public interface IAutoMouseBounds { Rectangle AutoMouseoverBounds(Actor self, WorldRenderer wr); }
 
-	// 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
 	{
 		IEnumerable<IOrderTargeter> Orders { get; }
@@ -296,12 +261,15 @@ namespace OpenRA.Traits
 	public interface ILoadsPalettes { void LoadPalettes(WorldRenderer wr); }
 	public interface ILoadsPlayerPalettes { void LoadPlayerPalettes(WorldRenderer wr, string playerName, Color playerColor, bool replaceExisting); }
 	public interface IPaletteModifier { void AdjustPalette(IReadOnlyDictionary<string, MutablePalette> b); }
-	public interface IPips { IEnumerable<PipType> GetPips(Actor self); }
 
 	[RequireExplicitImplementation]
 	public interface ISelectionBar { float GetValue(); Color GetColor(); bool DisplayWhenEmpty { get; } }
 
-	public interface ISelectionDecorations { void DrawRollover(Actor self, WorldRenderer worldRenderer); }
+	public interface ISelectionDecorations
+	{
+		IEnumerable<IRenderable> RenderRolloverAnnotations(Actor self, WorldRenderer worldRenderer);
+		IEnumerable<IRenderable> RenderSelectionAnnotations(Actor self, WorldRenderer worldRenderer, Color color);
+	}
 
 	public interface IMapPreviewSignatureInfo : ITraitInfoInterface
 	{