(#63) CharInfo: decouple from WPF and move into Shared assembly

src/WpfMath.Shared/CharFont.cs

@@ -1,7 +1,7 @@
 namespace WpfMath
 {
-    // Single character together with specific font.
-    internal class CharFont
+    /// <summary>Single character together with specific font.</summary>
+    public class CharFont
     {
         public CharFont(char character, int fontId)
         {

src/WpfMath/CharInfo.cs → src/WpfMath.Shared/CharInfo.cs

@@ -1,14 +1,14 @@
-using System.Windows.Media;
+using WpfMath.Fonts;
 
 namespace WpfMath
 {
-    // Single character togeter with information about font and metrics.
-    internal class CharInfo
+    /// <summary>Single character together with information about font and metrics.</summary>
+    public class CharInfo
     {
-        public CharInfo(char character, GlyphTypeface font, double size, int fontId, TexFontMetrics metrics)
+        public CharInfo(char character, IFontTypeface font, double size, int fontId, TexFontMetrics metrics)
         {
             this.Character = character;
-            this.Font = font;
+            Font = font;
             this.Size = size;
             FontId = fontId;
             this.Metrics = metrics;
@@ -20,10 +20,9 @@ public char Character
             set;
         }
 
-        public GlyphTypeface Font
+        public IFontTypeface Font
         {
             get;
-            set;
         }
 
         public double Size

src/WpfMath.Shared/Fonts/IFontTypeface.cs

@@ -0,0 +1,5 @@
+namespace WpfMath.Fonts;
+
+public interface IFontTypeface
+{
+}

src/WpfMath.Shared/TexFontMetrics.cs

@@ -1,7 +1,7 @@
 namespace WpfMath
 {
     // Specifies font metrics for single character.
-    internal class TexFontMetrics
+    public class TexFontMetrics
     {
         public TexFontMetrics(double width, double height, double depth, double italicWidth, double scale)
         {

src/WpfMath.Shared/WpfMath.Shared.csproj

@@ -19,4 +19,8 @@
         <InternalsVisibleTo Include="WpfMath.Tests" />
     </ItemGroup>
 
+    <ItemGroup>
+      <Folder Include="Atoms" />
+    </ItemGroup>
+
 </Project>

src/WpfMath.Tests/CharBoxTests.fs

@@ -1,16 +1,16 @@
 namespace WpfMath.Tests
 
-open System.Windows
+open System
 open System.Windows.Media
 
 open Foq
 open Xunit
 
 open WpfMath
 open WpfMath.Boxes
+open WpfMath.Fonts
 open WpfMath.Rendering
 open WpfMath.Exceptions
-open System
 
 type CharBoxTests() =
     static do Utils.initializeFontResourceLoading()
@@ -26,25 +26,25 @@ type CharBoxTests() =
         TexEnvironment(TexStyle.Display, mathFont, textFont)
 
     [<Fact>]
-    member _.``CharBox rendering calls to RenderGlyphRun``() =
+    member _.``CharBox rendering calls to RenderCharacter``() =
         let char = environment.MathFont.GetDefaultCharInfo('x', TexStyle.Display).Value
         let x = 0.5
         let y = 1.0
 
         let mockedRenderer = Mock.Of<IElementRenderer>()
         let charBox = CharBox(environment, char)
         charBox.RenderTo(mockedRenderer, x, y)
-        Mock.Verify(<@ mockedRenderer.RenderGlyphRun(any(), x, y, Brushes.Black) @>, once)
+        Mock.Verify(<@ mockedRenderer.RenderCharacter(any(), x, y, Brushes.Black) @>, once)
 
     [<Fact>]
-    member _.``Currently unsupporteded characters like "Å" should result in TexCharacterMappingNotFoundException``() =
+    member _.``Currently unsupported characters like "Å" should result in TexCharacterMappingNotFoundException``() =
         Assert.IsType<TexCharacterMappingNotFoundException>(
             environment.MathFont.GetDefaultCharInfo('Å', TexStyle.Display).Error)
 
     [<Fact>]
     member _.``CharBox GetGlyphRun for \text{∅} should throw the TexCharacterMappingNotFoundException``() =
         let atom = parse @"\text{∅}"
         let charBox : CharBox = downcast atom.CreateBox(environment)
-        let action = Func<obj>(fun () -> upcast charBox.GetGlyphRun(20.0, 0.5, 1.0))
+        let action = Func<obj>(fun () -> upcast WpfCharInfoEx.GetGlyphRun(charBox.Character, 20.0, 0.5, 1.0))
         let exc = Assert.Throws<TexCharacterMappingNotFoundException>(action)
         Assert.Equal("The Arial font does not support '∅' (U+2205) character.", exc.Message)

src/WpfMath.Tests/GeometryElementRendererTests.fs

@@ -1,6 +1,5 @@
 namespace WpfMath.Tests
 
-open System
 open System.Windows
 open System.Windows.Media
 
@@ -25,14 +24,11 @@ type GeometryElementRendererTests() =
         Mock.Verify(<@ box.RenderTo(renderer, 1.0, 2.0) @>, once)
 
     [<Fact>]
-    member _.``GeometryElementRenderer.RenderGlyphRun adds a PathGeometry group``() : unit =
+    member _.``GeometryElementRenderer.RenderCharacter adds a PathGeometry group``() : unit =
         let font = DefaultTexFont 20.0
         let environment = TexEnvironment(TexStyle.Display, font, font)
         let char = environment.MathFont.GetDefaultCharInfo('x', TexStyle.Display).Value
-        let charBox = CharBox(environment, char)
-        let glyphRun = charBox.GetGlyphRun(1.0, 0.0, 0.0)
-        let factory = Func<double, GlyphRun>(fun s -> glyphRun)
-        renderer.RenderGlyphRun(factory, 0.0, 0.0, Brushes.Black)
+        renderer.RenderCharacter(char, 0.0, 0.0, Brushes.Black)
 
         let group = Seq.exactlyOne geometry.Children :?> GeometryGroup
         Assert.IsType<PathGeometry>(Seq.exactlyOne group.Children) |> ignore

src/WpfMath/Boxes/CharBox.cs

@@ -1,8 +1,4 @@
-using System.ComponentModel;
-using System.Linq;
-using System.Windows;
 using System.Windows.Media;
-using WpfMath.Exceptions;
 using WpfMath.Rendering;
 
 namespace WpfMath.Boxes
@@ -26,38 +22,10 @@ public CharInfo Character
             private set;
         }
 
-        internal GlyphRun GetGlyphRun(double scale, double x, double y)
-        {
-            var typeface = this.Character.Font;
-            var characterInt = (int)this.Character.Character;
-            if (!typeface.CharacterToGlyphMap.TryGetValue(characterInt, out var glyphIndex))
-            {
-                var fontName = typeface.FamilyNames.Values.First();
-                var characterHex = characterInt.ToString("X4");
-                throw new TexCharacterMappingNotFoundException(
-                    $"The {fontName} font does not support '{this.Character.Character}' (U+{characterHex}) character.");
-            }
-#if NET452
-            var glyphRun = new GlyphRun(typeface, 0, false, this.Character.Size * scale,
-                new ushort[] { glyphIndex }, new Point(x * scale, y * scale),
-                new double[] { typeface.AdvanceWidths[glyphIndex] }, null, null, null, null, null, null);
-#else
-            var glyphRun = new GlyphRun((float)scale);
-            ((ISupportInitialize)glyphRun).BeginInit();
-            glyphRun.GlyphTypeface = typeface;
-            glyphRun.FontRenderingEmSize = this.Character.Size * scale;
-            glyphRun.GlyphIndices = new[] { glyphIndex };
-            glyphRun.BaselineOrigin = new Point(x * scale, y * scale);
-            glyphRun.AdvanceWidths = new[] { typeface.AdvanceWidths[glyphIndex] };
-            ((ISupportInitialize)glyphRun).EndInit();
-#endif
-            return glyphRun;
-        }
-
         public override void RenderTo(IElementRenderer renderer, double x, double y)
         {
             var color = this.Foreground ?? Brushes.Black;
-            renderer.RenderGlyphRun(scale => this.GetGlyphRun(scale, x, y), x, y, color);
+            renderer.RenderCharacter(Character, x, y, color);
         }
 
         public override int GetLastFontId()

src/WpfMath/DefaultTexFont.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using WpfMath.Exceptions;
+using WpfMath.Fonts;
 using WpfMath.Utils;
 
 namespace WpfMath
@@ -108,7 +109,7 @@ public CharInfo GetNextLargerCharInfo(CharInfo charInfo, TexStyle style)
             var newFontInfo = fontInfoList[charFont.FontId];
             return new CharInfo(
                 charFont.Character,
-                newFontInfo.Font,
+                new WpfGlyphTypeface(newFontInfo.Font),
                 GetSizeFactor(style),
                 charFont.FontId,
                 GetMetrics(charFont, GetSizeFactor(style)).Value);
@@ -176,7 +177,7 @@ public Result<CharInfo> GetCharInfo(CharFont charFont, TexStyle style)
             var size = GetSizeFactor(style);
             var fontInfo = fontInfoList[charFont.FontId];
             var metrics = GetMetrics(charFont, size);
-            return metrics.Map(m => new CharInfo(charFont.Character, fontInfo.Font, size, charFont.FontId, m));
+            return metrics.Map(m => new CharInfo(charFont.Character, new WpfGlyphTypeface(fontInfo.Font), size, charFont.FontId, m));
         }
 
         public double GetKern(CharFont leftCharFont, CharFont rightCharFont, TexStyle style)

src/WpfMath/Fonts/WpfCharInfoEx.cs

@@ -0,0 +1,37 @@
+using System.Linq;
+using System.Windows;
+using System.Windows.Media;
+using WpfMath.Exceptions;
+
+namespace WpfMath.Fonts;
+
+internal static class WpfCharInfoEx
+{
+    public static GlyphRun GetGlyphRun(this CharInfo info, double x, double y, double scale)
+    {
+        var typeface = ((WpfGlyphTypeface)info.Font).Typeface;
+        var characterInt = (int)info.Character;
+        if (!typeface.CharacterToGlyphMap.TryGetValue(characterInt, out var glyphIndex))
+        {
+            var fontName = typeface.FamilyNames.Values.First();
+            var characterHex = characterInt.ToString("X4");
+            throw new TexCharacterMappingNotFoundException(
+                $"The {fontName} font does not support '{info.Character}' (U+{characterHex}) character.");
+        }
+#if NET452
+            var glyphRun = new GlyphRun(typeface, 0, false, info.Size * scale,
+                new ushort[] { glyphIndex }, new Point(x * scale, y * scale),
+                new double[] { typeface.AdvanceWidths[glyphIndex] }, null, null, null, null, null, null);
+#else
+        var glyphRun = new GlyphRun((float)scale);
+        ((ISupportInitialize)glyphRun).BeginInit();
+        glyphRun.GlyphTypeface = typeface;
+        glyphRun.FontRenderingEmSize = info.Size * scale;
+        glyphRun.GlyphIndices = new[] { glyphIndex };
+        glyphRun.BaselineOrigin = new Point(x * scale, y * scale);
+        glyphRun.AdvanceWidths = new[] { typeface.AdvanceWidths[glyphIndex] };
+        ((ISupportInitialize)glyphRun).EndInit();
+#endif
+        return glyphRun;
+    }
+}

src/WpfMath/Fonts/WpfGlyphTypeface.cs

@@ -0,0 +1,5 @@
+using System.Windows.Media;
+
+namespace WpfMath.Fonts;
+
+internal record WpfGlyphTypeface(GlyphTypeface Typeface) : IFontTypeface;

src/WpfMath/Rendering/GeometryElementRenderer.cs

@@ -4,6 +4,7 @@
 using System.Windows;
 using System.Windows.Media;
 using WpfMath.Boxes;
+using WpfMath.Fonts;
 using WpfMath.Rendering.Transformations;
 
 namespace WpfMath.Rendering
@@ -22,9 +23,9 @@ public GeometryElementRenderer(GeometryGroup geometry, double scale)
 
         public void RenderElement(Box box, double x, double y) => box.RenderTo(this, x, y);
 
-        public void RenderGlyphRun(Func<double, GlyphRun> scaledGlyphFactory, double x, double y, Brush foreground)
+        public void RenderCharacter(CharInfo info, double x, double y, Brush foreground)
         {
-            var glyph = scaledGlyphFactory(_scale);
+            var glyph = info.GetGlyphRun(x, y, _scale);
             var glyphGeometry = glyph.BuildGeometry();
             _geometry.Children.Add(glyphGeometry);
         }

src/WpfMath/Rendering/IElementRenderer.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Windows;
 using System.Windows.Media;
 using WpfMath.Boxes;
@@ -19,13 +18,11 @@ public interface IElementRenderer
         /// </remarks>
         void RenderElement(Box box, double x, double y);
 
-        /// <summary>Renders a glyph run (e.g. a character).</summary>
-        /// <param name="scaledGlyphFactory">Function to generate a glyph run for the chosen scale.</param>
-        /// <param name="x">An X coordinate of the top left corner.</param>
-        /// <param name="y">An Y coordinate of the top left corner.</param>
-        /// <param name="foreground">Glyph foreground color.</param>
-        // TODO[F]: Scale the GlyphRun in the implementations, replace the factory with the initial (unscaled) GlyphRun
-        void RenderGlyphRun(Func<double, GlyphRun> scaledGlyphFactory, double x, double y, Brush foreground);
+        /// <summary>
+        /// Renders a character denoted by <paramref name="info"/> at the chosen coordinates, using the color
+        /// <paramref name="foreground"/>.
+        /// </summary>
+        void RenderCharacter(CharInfo info, double x, double y, Brush foreground); // TODO[#63]: Get rid of Brush type.
 
         /// <summary>Renders a rectangle.</summary>
         /// <param name="rectangle">Rectangle to render.</param>

src/WpfMath/Rendering/WpfElementRenderer.cs

@@ -3,6 +3,7 @@
 using System.Windows;
 using System.Windows.Media;
 using WpfMath.Boxes;
+using WpfMath.Fonts;
 using WpfMath.Rendering.Transformations;
 
 namespace WpfMath.Rendering
@@ -42,9 +43,9 @@ public void RenderElement(Box box, double x, double y)
             _foregroundContext.Pop();
         }
 
-        public void RenderGlyphRun(Func<double, GlyphRun> scaledGlyphFactory, double x, double y, Brush foreground)
+        public void RenderCharacter(CharInfo info, double x, double y, Brush foreground)
         {
-            var glyphRun = scaledGlyphFactory(_scale);
+            var glyphRun = info.GetGlyphRun(x, y, _scale);
             _foregroundContext.DrawGlyphRun(foreground, glyphRun);
         }
 

src/WpfMath/SystemFont.cs

@@ -2,6 +2,7 @@
 using System.Windows;
 using System.Windows.Media;
 using WpfMath.Exceptions;
+using WpfMath.Fonts;
 using WpfMath.Utils;
 
 namespace WpfMath
@@ -42,7 +43,8 @@ public Result<CharInfo> GetCharInfo(char character, string textStyle, TexStyle s
             }
 
             var metrics = GetFontMetrics(character, typeface);
-            return Result.Ok(new CharInfo(character, glyphTypeface, 1.0, TexFontUtilities.NoFontId, metrics));
+            return Result.Ok(
+                new CharInfo(character, new WpfGlyphTypeface(glyphTypeface), 1.0, TexFontUtilities.NoFontId, metrics));
         }
 
         public Result<CharInfo> GetCharInfo(CharFont charFont, TexStyle style) =>

src/WpfMath/TexFormula.cs

@@ -104,7 +104,7 @@ internal Box CreateBox(TexEnvironment environment)
 
         internal static SystemFont GetSystemFont(string fontName, double size)
         {
-            var fontFamily = Fonts.SystemFontFamilies.First(
+            var fontFamily = System.Windows.Media.Fonts.SystemFontFamilies.First(
                 ff => ff.ToString() == fontName || ff.FamilyNames.Values?.Contains(fontName) == true);
             return new SystemFont(size, fontFamily);
         }