Merge pull request AvaloniaUI#3202 from Gillibald/feature/GlyphRun

GlyphRun support

build/HarfBuzzSharp.props

@@ -1,6 +1,6 @@
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup>
-    <PackageReference Include="HarfBuzzSharp" Version="2.6.1-rc.153" />
-    <PackageReference Condition="'$(IncludeLinuxSkia)' == 'true'" Include="HarfBuzzSharp.NativeAssets.Linux" Version="2.6.1-rc.153" />
+    <PackageReference Include="HarfBuzzSharp" Version="2.6.1" />
+    <PackageReference Condition="'$(IncludeLinuxSkia)' == 'true'" Include="HarfBuzzSharp.NativeAssets.Linux" Version="2.6.1" />
   </ItemGroup>
 </Project>

build/SkiaSharp.props

@@ -1,6 +1,6 @@
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup>
-    <PackageReference Include="SkiaSharp" Version="1.68.1-rc.153" />
-    <PackageReference Condition="'$(IncludeLinuxSkia)' == 'true'" Include="SkiaSharp.NativeAssets.Linux" Version="1.68.1-rc.153" />
+    <PackageReference Include="SkiaSharp" Version="1.68.1" />
+    <PackageReference Condition="'$(IncludeLinuxSkia)' == 'true'" Include="SkiaSharp.NativeAssets.Linux" Version="1.68.1" />
   </ItemGroup>
 </Project>

samples/RenderDemo/MainWindow.xaml

@@ -41,6 +41,9 @@
       <TabItem Header="RenderTargetBitmap">
         <pages:RenderTargetBitmapPage/>
       </TabItem>
+      <TabItem Header="GlyphRun">
+        <pages:GlyphRunPage/>
+      </TabItem>
     </TabControl>
   </DockPanel>
 </Window>

samples/RenderDemo/Pages/GlyphRunPage.xaml

@@ -0,0 +1,14 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             x:Class="RenderDemo.Pages.GlyphRunPage">
+  <Border
+    Background="White">
+    <DrawingPresenter
+      x:Name="drawingPresenter"
+      Stretch="None">
+    </DrawingPresenter>
+  </Border>
+</UserControl>

samples/RenderDemo/Pages/GlyphRunPage.xaml.cs

@@ -0,0 +1,80 @@
+using System;
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Markup.Xaml;
+using Avalonia.Media;
+using Avalonia.Threading;
+
+namespace RenderDemo.Pages
+{
+    public class GlyphRunPage : UserControl
+    {
+        private DrawingPresenter _drawingPresenter;
+        private GlyphTypeface _glyphTypeface = Typeface.Default.GlyphTypeface;
+        private readonly Random _rand = new Random();
+        private ushort[] _glyphIndices = new ushort[1];
+        private float _fontSize = 20;
+        private int _direction = 10;
+
+        public GlyphRunPage()
+        {
+            this.InitializeComponent();
+        }
+
+        private void InitializeComponent()
+        {
+            AvaloniaXamlLoader.Load(this);
+
+            _drawingPresenter = this.FindControl<DrawingPresenter>("drawingPresenter");
+
+            DispatcherTimer.Run(() =>
+            {
+                UpdateGlyphRun();
+
+                return true;
+            }, TimeSpan.FromSeconds(1));
+        }
+
+        private void UpdateGlyphRun()
+        {
+            var c = (uint)_rand.Next(65, 90);
+
+            if (_fontSize + _direction > 200)
+            {
+                _direction = -10;
+            }
+
+            if (_fontSize + _direction < 20)
+            {
+                _direction = 10;
+            }
+
+            _fontSize += _direction;
+
+            _glyphIndices[0] = _glyphTypeface.GetGlyph(c);
+
+            var scale = (double)_fontSize / _glyphTypeface.DesignEmHeight;
+
+            var drawingGroup = new DrawingGroup();
+
+            var glyphRunDrawing = new GlyphRunDrawing
+            {
+                Foreground = Brushes.Black,
+                GlyphRun = new GlyphRun(_glyphTypeface, _fontSize, _glyphIndices),
+                BaselineOrigin = new Point(0, -_glyphTypeface.Ascent * scale)
+            };
+
+            drawingGroup.Children.Add(glyphRunDrawing);
+
+            var geometryDrawing = new GeometryDrawing
+            {
+                Pen = new Pen(Brushes.Black),
+                Geometry = new RectangleGeometry { Rect = glyphRunDrawing.GlyphRun.Bounds }
+            };
+
+            drawingGroup.Children.Add(geometryDrawing);
+
+            _drawingPresenter.Drawing = drawingGroup;
+        }
+    }
+}

src/Avalonia.Visuals/Media/CharacterHit.cs

@@ -0,0 +1,68 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+
+namespace Avalonia.Media
+{
+    /// <summary>
+    ///     Represents information about a character hit within a glyph run.
+    /// </summary>
+    /// <remarks>
+    ///     The CharacterHit structure provides information about the index of the first
+    ///     character that got hit as well as information about leading or trailing edge.
+    /// </remarks>
+    public readonly struct CharacterHit : IEquatable<CharacterHit>
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="CharacterHit"/> structure.
+        /// </summary>
+        /// <param name="firstCharacterIndex">Index of the first character that got hit.</param>
+        /// <param name="trailingLength">In the case of a leading edge, this value is 0. In the case of a trailing edge,
+        /// this value is the number of code points until the next valid caret position.</param>
+        public CharacterHit(int firstCharacterIndex, int trailingLength = 0)
+        {
+            FirstCharacterIndex = firstCharacterIndex;
+
+            TrailingLength = trailingLength;
+        }
+
+        /// <summary>
+        ///     Gets the index of the first character that got hit.
+        /// </summary>
+        public int FirstCharacterIndex { get; }
+
+        /// <summary>
+        ///     Gets the trailing length value for the character that got hit.
+        /// </summary>
+        public int TrailingLength { get; }
+
+        public bool Equals(CharacterHit other)
+        {
+            return FirstCharacterIndex == other.FirstCharacterIndex && TrailingLength == other.TrailingLength;
+        }
+
+        public override bool Equals(object obj)
+        {
+            return obj is CharacterHit other && Equals(other);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                return FirstCharacterIndex * 397 ^ TrailingLength;
+            }
+        }
+
+        public static bool operator ==(CharacterHit left, CharacterHit right)
+        {
+            return left.Equals(right);
+        }
+
+        public static bool operator !=(CharacterHit left, CharacterHit right)
+        {
+            return !left.Equals(right);
+        }
+    }
+}

src/Avalonia.Visuals/Media/DrawingContext.cs

@@ -187,6 +187,22 @@ public void DrawText(IBrush foreground, Point origin, FormattedText text)
             }
         }
 
+        /// <summary>
+        /// Draws a glyph run.
+        /// </summary>
+        /// <param name="foreground">The foreground brush.</param>
+        /// <param name="glyphRun">The glyph run.</param>
+        /// <param name="baselineOrigin">The baseline origin of the glyph run.</param>
+        public void DrawGlyphRun(IBrush foreground, GlyphRun glyphRun, Point baselineOrigin)
+        {
+            Contract.Requires<ArgumentNullException>(glyphRun != null);
+
+            if (foreground != null)
+            {
+                PlatformImpl.DrawGlyphRun(foreground, glyphRun, baselineOrigin);
+            }
+        }
+
         /// <summary>
         /// Draws a filled rectangle.
         /// </summary>