Add support for font scaling.

OpenRA.Game/Graphics/SpriteFont.cs

@@ -29,27 +29,37 @@ namespace OpenRA.Graphics
 		readonly Face face;
 		readonly Cache<Pair<char, Color>, GlyphInfo> glyphs;
 
-		public SpriteFont(string name, byte[] data, int size, SheetBuilder builder)
+		float deviceScale;
+
+		public SpriteFont(string name, byte[] data, int size, float scale, SheetBuilder builder)
 		{
 			if (builder.Type != SheetType.BGRA)
 				throw new ArgumentException("The sheet builder must create BGRA sheets.", "builder");
 
+			deviceScale = scale;
 			this.size = size;
 			this.builder = builder;
 
 			face = new Face(Library, data, 0);
-			face.SetPixelSizes((uint)size, (uint)size);
+			face.SetPixelSizes((uint)(size * deviceScale), (uint)(size * deviceScale));
 
 			glyphs = new Cache<Pair<char, Color>, GlyphInfo>(CreateGlyph, Pair<char, Color>.EqualityComparer);
 
 			// PERF: Cache these delegates for Measure calls.
 			Func<char, float> characterWidth = character => glyphs[Pair.New(character, Color.White)].Advance;
-			lineWidth = line => line.Sum(characterWidth);
+			lineWidth = line => line.Sum(characterWidth) / deviceScale;
 
 			PrecacheColor(Color.White, name);
 			PrecacheColor(Color.Red, name);
 		}
 
+		public void SetScale(float scale)
+		{
+			deviceScale = scale;
+			face.SetPixelSizes((uint)(size * deviceScale), (uint)(size * deviceScale));
+			glyphs.Clear();
+		}
+
 		void PrecacheColor(Color c, string name)
 		{
 			using (new PerfTimer("PrecacheColor {0} {1}px {2}".F(name, size, c.Name)))
@@ -75,9 +85,10 @@ namespace OpenRA.Graphics
 				var g = glyphs[Pair.New(s, c)];
 				Game.Renderer.RgbaSpriteRenderer.DrawSprite(g.Sprite,
 					new float2(
-						(int)Math.Round(p.X + g.Offset.X, 0),
+						(int)Math.Round(p.X * deviceScale + g.Offset.X, 0) / deviceScale,
-						p.Y + g.Offset.Y));
+						p.Y + g.Offset.Y / deviceScale),
-				p.X += g.Advance;
+						g.Sprite.Size / deviceScale);
+				p.X += g.Advance / deviceScale;
 			}
 		}
 
@@ -85,10 +96,10 @@ namespace OpenRA.Graphics
 		{
 			if (offset > 0)
 			{
-				DrawText(text, location + new float2(-offset, 0), bg);
+				DrawText(text, location + new float2(-offset / deviceScale, 0), bg);
-				DrawText(text, location + new float2(offset, 0), bg);
+				DrawText(text, location + new float2(offset / deviceScale, 0), bg);
-				DrawText(text, location + new float2(0, -offset), bg);
+				DrawText(text, location + new float2(0, -offset / deviceScale), bg);
-				DrawText(text, location + new float2(0, offset), bg);
+				DrawText(text, location + new float2(0, offset / deviceScale), bg);
 			}
 
 			DrawText(text, location, fg);

OpenRA.Game/Primitives/Cache.cs

@@ -39,6 +39,8 @@ namespace OpenRA.Primitives
 		public bool ContainsKey(T key) { return cache.ContainsKey(key); }
 		public bool TryGetValue(T key, out U value) { return cache.TryGetValue(key, out value); }
 		public int Count { get { return cache.Count; } }
+		public void Clear() { cache.Clear(); }
+
 		public ICollection<T> Keys { get { return cache.Keys; } }
 		public ICollection<U> Values { get { return cache.Values; } }
 		public IEnumerator<KeyValuePair<T, U>> GetEnumerator() { return cache.GetEnumerator(); }

OpenRA.Game/Renderer.cs

@@ -86,8 +86,15 @@ namespace OpenRA
 					fontSheetBuilder.Dispose();
 				fontSheetBuilder = new SheetBuilder(SheetType.BGRA);
 				Fonts = modData.Manifest.Fonts.ToDictionary(x => x.Key,
-					x => new SpriteFont(x.Value.First, modData.DefaultFileSystem.Open(x.Value.First).ReadAllBytes(), x.Value.Second, Device.WindowScale, fontSheetBuilder)).AsReadOnly();
+					x => new SpriteFont(x.Value.First, modData.DefaultFileSystem.Open(x.Value.First).ReadAllBytes(),
+										x.Value.Second, Device.WindowScale, fontSheetBuilder)).AsReadOnly();
 			}
+
+			Device.OnWindowScaleChanged += (before, after) =>
+			{
+				foreach (var f in Fonts)
+					f.Value.SetScale(after);
+			};
 		}
 
 		public void InitializeDepthBuffer(MapGrid mapGrid)