Store mapped image coordinates in chrome.xml; port most of specialbin.png to this format

OpenRa.Game/Graphics/MappedImage.cs

@@ -0,0 +1,31 @@
+using System.Xml;
+using System.Drawing;
+using Ijw.DirectX;
+using System.IO;
+namespace OpenRa.Game.Graphics
+{
+	class MappedImage
+	{
+		readonly Rectangle rect;
+		public readonly string Src;
+		public readonly string Name;
+
+		public MappedImage(string defaultSrc, XmlElement e)
+		{
+			Src = (e.HasAttribute("src")) ? e.GetAttribute("src") : defaultSrc;
+			Name = e.GetAttribute("name");
+			if (Src == null)
+				throw new InvalidDataException("Image src missing");
+
+			rect = new Rectangle(int.Parse(e.GetAttribute("x")),
+								 int.Parse(e.GetAttribute("y")),
+								 int.Parse(e.GetAttribute("width")),
+								 int.Parse(e.GetAttribute("height")));
+		}
+
+		public Sprite GetImage(Renderer r, Sheet s)
+		{
+			return new Sprite(s, rect, TextureChannel.Alpha);
+		}
+	}
+}