Represent characters with Unicode codepoint

src/SixLabors.Fonts/FileFontInstance.cs

@@ -32,8 +32,8 @@ public FileFontInstance(string path)
 
         public int LineHeight => this.font.Value.LineHeight;
 
-        public GlyphInstance GetGlyph(char character)
-            => this.font.Value.GetGlyph(character);
+        public GlyphInstance GetGlyph(int codePoint)
+            => this.font.Value.GetGlyph(codePoint);
 
         public Vector2 GetOffset(GlyphInstance glyph, GlyphInstance previousGlyph)
             => this.font.Value.GetOffset(glyph, previousGlyph);

src/SixLabors.Fonts/Font.cs

@@ -147,11 +147,11 @@ public Font(Font prototype, float size)
         /// <summary>
         /// Gets the glyph.
         /// </summary>
-        /// <param name="character">The character.</param>
+        /// <param name="codePoint">The code point of the character.</param>
         /// <returns>Returns the glyph</returns>
-        internal Glyph GetGlyph(char character)
+        internal Glyph GetGlyph(int codePoint)
         {
-            return new Glyph(this.instance.Value.GetGlyph(character), this.Size);
+            return new Glyph(this.instance.Value.GetGlyph(codePoint), this.Size);
         }
 
         private IFontInstance LoadInstanceInternal()

src/SixLabors.Fonts/FontInstance.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.IO;
 using System.Numerics;
 using SixLabors.Fonts.Tables.General;
@@ -82,19 +83,24 @@ internal FontInstance(NameTable nameTable, CMapTable cmap, GlyphTable glyphs, OS
 
         public FontDescription Description { get; }
 
-        internal ushort GetGlyphIndex(char character)
+        internal ushort GetGlyphIndex(int codePoint)
         {
-            return this.cmap.GetGlyphId(character);
+            if (codePoint > short.MaxValue)
+            {
+                throw new NotImplementedException("cmap table doesn't support 32-bit characters yet.");
+            }
+
+            return this.cmap.GetGlyphId(codePoint);
         }
 
         /// <summary>
         /// Gets the glyph.
         /// </summary>
-        /// <param name="character">The character.</param>
+        /// <param name="codePoint">The code point of the character.</param>
         /// <returns>the glyph for a known character.</returns>
-        public GlyphInstance GetGlyph(char character)
+        public GlyphInstance GetGlyph(int codePoint)
         {
-            ushort idx = this.GetGlyphIndex(character);
+            ushort idx = this.GetGlyphIndex(codePoint);
             if (this.glyphCache[idx] == null)
             {
                 ushort advanceWidth = this.horizontalMetrics.GetAdvancedWidth(idx);

src/SixLabors.Fonts/GlyphMetric.cs

@@ -14,20 +14,26 @@ namespace SixLabors.Fonts
         /// <summary>
         /// Initializes a new instance of the <see cref="GlyphMetric"/> struct.
         /// </summary>
-        /// <param name="character">The character.</param>
+        /// <param name="codePoint">Unicode codepoint of the character.</param>
         /// <param name="bounds">The bounds.</param>
         /// <param name="isControlCharacter">Whether the character is a control character.</param>
-        public GlyphMetric(char character, RectangleF bounds, bool isControlCharacter)
+        public GlyphMetric(int codePoint, RectangleF bounds, bool isControlCharacter)
         {
-            this.Character = character;
+            this.Codepoint = codePoint;
+            this.Character = char.ConvertFromUtf32(codePoint);
             this.Bounds = bounds;
             this.IsControlCharacter = isControlCharacter;
         }
 
         /// <summary>
-        /// Gets the character.
+        /// Gets the Unicode codepoint of the character.
         /// </summary>
-        public char Character { get; }
+        public int Codepoint { get; }
+
+        /// <summary>
+        /// Gets the UTF-16 encoded character.
+        /// </summary>
+        public string Character { get; }
 
         /// <summary>
         /// Gets the character bounds.
@@ -42,7 +48,7 @@ public GlyphMetric(char character, RectangleF bounds, bool isControlCharacter)
         /// <inheritdoc/>
         public override string ToString()
         {
-            return $"Char: {this.Character}, bounds: {this.Bounds}, is control char: {this.IsControlCharacter}";
+            return $"Character: {this.Character}, bounds: {this.Bounds}, is control char: {this.IsControlCharacter}";
         }
     }
 }

src/SixLabors.Fonts/IFontInstance.cs

@@ -19,7 +19,7 @@ internal interface IFontInstance
 
         short LineGap { get; }
 
-        GlyphInstance GetGlyph(char character);
+        GlyphInstance GetGlyph(int codePoint);
 
         Vector2 GetOffset(GlyphInstance glyph, GlyphInstance previousGlyph);
     }

src/SixLabors.Fonts/Tables/General/CMap/CMapSubTable.cs

@@ -24,6 +24,6 @@ public CMapSubTable(PlatformIDs platform, ushort encoding, ushort format)
 
         public ushort Encoding { get; }
 
-        public abstract ushort GetGlyphId(char character);
+        public abstract ushort GetGlyphId(int codePoint);
     }
 }

src/SixLabors.Fonts/Tables/General/CMap/Format0SubTable.cs

@@ -19,9 +19,9 @@ public Format0SubTable(ushort language, PlatformIDs platform, ushort encoding, b
 
         public ushort Language { get; }
 
-        public override ushort GetGlyphId(char character)
+        public override ushort GetGlyphId(int codePoint)
         {
-            uint b = character;
+            uint b = (uint)codePoint;
             if (b >= this.GlyphIds.Length)
             {
                 return 0;

src/SixLabors.Fonts/Tables/General/CMap/Format4SubTable.cs

@@ -22,9 +22,9 @@ public Format4SubTable(ushort language, PlatformIDs platform, ushort encoding, S
 
         public ushort Language { get; }
 
-        public override ushort GetGlyphId(char character)
+        public override ushort GetGlyphId(int codePoint)
         {
-            uint charAsInt = character;
+            uint charAsInt = (uint)codePoint;
 
             foreach (Segment seg in this.Segments)
             {

src/SixLabors.Fonts/Tables/General/CMapTable.cs

@@ -40,19 +40,19 @@ public CMapTable(CMapSubTable[] tables)
             this.table = table;
         }
 
-        public ushort GetGlyphId(char character)
+        public ushort GetGlyphId(int codePoint)
         {
             // use the best match only
             if (this.table != null)
             {
-                return this.table.GetGlyphId(character);
+                return this.table.GetGlyphId(codePoint);
             }
 
             // didn't have a windows match just use any and hope for the best
             foreach (CMapSubTable t in this.Tables)
             {
                 // keep looking until we have an index thats not the fallback.
-                ushort index = t.GetGlyphId(character);
+                ushort index = t.GetGlyphId(codePoint);
                 if (index > 0)
                 {
                     return index;

src/SixLabors.Fonts/Tables/General/HorizontalMetricsTable.cs

@@ -26,7 +26,7 @@ public ushort GetAdvancedWidth(int glyphIndex)
             return this.advancedWidths[glyphIndex];
         }
 
-        internal short GetLeftSideBearing(ushort glyphIndex)
+        internal short GetLeftSideBearing(int glyphIndex)
         {
             if (glyphIndex >= this.leftSideBearings.Length)
             {