Implemented an interface that allows traits to add custom information to tooltips.

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -136,6 +136,12 @@ namespace OpenRA.Traits
 		bool IsOwnerRowVisible { get; }
 	}
 
+	public interface IProvideTooltipInfo
+	{
+		bool IsTooltipVisible(Player forPlayer);
+		string TooltipText { get; }
+	}
+
 	public interface IDisabledTrait { bool IsTraitDisabled { get; } }
 	public interface IDisable { bool Disabled { get; } }
 	public interface IExplodeModifier { bool ShouldExplode(Actor self); }

OpenRA.Game/Widgets/ViewportControllerWidget.cs

@@ -27,6 +27,7 @@ namespace OpenRA.Widgets
 
 		public WorldTooltipType TooltipType { get; private set; }
 		public IToolTip ActorTooltip { get; private set; }
+		public IEnumerable<IProvideTooltipInfo> ActorTooltipExtra { get; private set; }
 		public FrozenActor FrozenActorTooltip { get; private set; }
 
 		public int EdgeScrollThreshold = 15;
@@ -109,6 +110,7 @@ namespace OpenRA.Widgets
 			if (underCursor != null)
 			{
 				ActorTooltip = underCursor.TraitsImplementing<IToolTip>().First();
+				ActorTooltipExtra = underCursor.TraitsImplementing<IProvideTooltipInfo>();
 				TooltipType = WorldTooltipType.Actor;
 				return;
 			}
@@ -120,6 +122,7 @@ namespace OpenRA.Widgets
 			if (frozen != null)
 			{
 				FrozenActorTooltip = frozen;
+				ActorTooltipExtra = frozen.Actor.TraitsImplementing<IProvideTooltipInfo>();
 				TooltipType = WorldTooltipType.FrozenActor;
 			}
 		}

OpenRA.Mods.Common/Widgets/Logic/Ingame/WorldTooltipLogic.cs

@@ -9,6 +9,7 @@
 #endregion
 
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 using OpenRA.Traits;
 using OpenRA.Widgets;
@@ -24,6 +25,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var label = widget.Get<LabelWidget>("LABEL");
 			var flag = widget.Get<ImageWidget>("FLAG");
 			var owner = widget.Get<LabelWidget>("OWNER");
+			var extras = widget.Get<LabelWidget>("EXTRA");
 
 			var font = Game.Renderer.Fonts[label.Font];
 			var ownerFont = Game.Renderer.Fonts[owner.Font];
@@ -33,6 +35,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var flagRace = "";
 			var ownerName = "";
 			var ownerColor = Color.White;
+			var extraText = "";
 
 			var singleHeight = widget.Get("SINGLE_HEIGHT").Bounds.Height;
 			var doubleHeight = widget.Get("DOUBLE_HEIGHT").Bounds.Height;
@@ -42,6 +45,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				if (viewport == null || viewport.TooltipType == WorldTooltipType.None)
 					return;
 
+				var index = 0;
+				extraText = "";
 				showOwner = false;
 
 				Player o = null;
@@ -71,7 +76,22 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 						}
 				}
 
-				var textWidth = font.Measure(labelText).X;
+				if (viewport.ActorTooltipExtra != null)
+				{
+					foreach (var info in viewport.ActorTooltipExtra)
+					{
+						if (info.IsTooltipVisible(world.LocalPlayer))
+						{
+							if (index != 0)
+								extraText += "\n";
+							extraText += info.TooltipText;
+							index++;
+						}
+					}
+				}
+
+				var textWidth = Math.Max(font.Measure(labelText).X, font.Measure(extraText).X);
+
 				if (textWidth != cachedWidth)
 				{
 					label.Bounds.Width = textWidth;
@@ -86,9 +106,15 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					widget.Bounds.Height = doubleHeight;
 					widget.Bounds.Width = Math.Max(widget.Bounds.Width,
 						owner.Bounds.X + ownerFont.Measure(ownerName).X + label.Bounds.X);
+					index++;
 				}
 				else
 					widget.Bounds.Height = singleHeight;
+
+				if (extraText != "")
+				{
+					widget.Bounds.Height += font.Measure(extraText).Y + extras.Bounds.Height;
+				}
 			};
 
 			label.GetText = () => labelText;
@@ -98,6 +124,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			owner.IsVisible = () => showOwner;
 			owner.GetText = () => ownerName;
 			owner.GetColor = () => ownerColor;
+			extras.GetText = () => extraText;
 		}
 	}
 }

mods/cnc/chrome/tooltips.yaml

@@ -45,6 +45,11 @@ Background@WORLD_TOOLTIP:
 			Y: 19
 			Height: 23
 			Font: Bold
+		Label@EXTRA:
+			X: 5
+			Y: 45
+			Height: 4
+			Font: Bold
 
 Background@PRODUCTION_TOOLTIP:
 	Logic: ProductionTooltipLogic

mods/d2k/chrome/tooltips.yaml

@@ -49,6 +49,11 @@ Background@WORLD_TOOLTIP:
 			Y: 25
 			Height: 23
 			Font: Bold
+		Label@EXTRA:
+			X: 7
+			Y: 55
+			Height: 4
+			Font: Bold
 
 Background@SPAWN_TOOLTIP:
 	Logic: SpawnSelectorTooltipLogic

mods/ra/chrome/tooltips.yaml

@@ -49,6 +49,11 @@ Background@WORLD_TOOLTIP:
 			Y: 22
 			Height: 23
 			Font: Bold
+		Label@EXTRA:
+			X: 7
+			Y: 48
+			Height: 4
+			Font: Bold
 
 Background@SPAWN_TOOLTIP:
 	Logic: SpawnSelectorTooltipLogic