Font smoothing is broken in Avalonia 11.1?

[alvahtin]

On the left is a project on Avalonia 11.0.10, on the right is Avalonia 11.1.1. The TextBlock component does not smooth the text. Is this a bug?

[alvahtin]

This problem for CheckBox and TextBox too

[rabbitism]

Looks like antialiasing is disabled. But it should be enabled by default.

[timunie]

Please upload a minimal sample as this seems to be wired to me. Also nobody else reported it, so unlikely a bug but who knows 🤣

[alvahtin]

this is problem in my control GroupBox. The controls that are located on it have non-antialiased fonts. My code:

GroupBox.axaml:

<HeaderedContentControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             x:Class="FoundationLibrary.Controls.GroupBox"
             BorderThickness="1">
  <HeaderedContentControl.Resources>
    <ResourceDictionary>
      <ResourceDictionary.MergedDictionaries>
        <ResourceInclude Source="avares://TestAvalonia/Controls/GroupBoxTheme.axaml" />
      </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>  
  </HeaderedContentControl.Resources>
</HeaderedContentControl>

GroupBox.axaml.cs:

using Avalonia.Controls.Primitives;

namespace FoundationLibrary.Controls;

/// <summary>
/// Эдемент управления с рамкой и заголовком
/// </summary>
public partial class GroupBox : HeaderedContentControl
{
    /// <summary>
    /// Конструктор
    /// </summary>
    public GroupBox()
    {
        InitializeComponent();
    }
}

GroupBoxTheme.axaml:

<ResourceDictionary xmlns="https://github.com/avaloniaui"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:conv="using:FoundationLibrary.Controls"
                    xmlns:ctrl="using:FoundationLibrary.Controls"
                    xmlns:sys="using:System">


  <ControlTheme x:Key="{x:Type ctrl:GroupBox}" TargetType="ctrl:GroupBox">
    <Setter Property="Template">
      <ControlTemplate>
        <Grid Name="GBGrid"
              ColumnDefinitions="Auto *" RowDefinitions="Auto *">
          <Grid.Resources>
            <ResourceDictionary>
              <sys:Double x:Key="GBBorderPadding">3</sys:Double>
              <sys:Double x:Key="GBBorderMargin">0</sys:Double>
              <!-- Copied from SimpleTheme's .../Accents/Base.xaml. These are not defined in FluentTheme. -->
              <ResourceDictionary.ThemeDictionaries>
                <ResourceDictionary x:Key="Default">
                  <Color x:Key="ThemeBorderMidColor">LightGray</Color>
                  <SolidColorBrush x:Key="ThemeBorderMidBrush" Color="{StaticResource ThemeBorderMidColor}" />
                </ResourceDictionary>
                <ResourceDictionary x:Key="Light">
                  <Color x:Key="ThemeBorderMidColor">LightGray</Color>
                  <SolidColorBrush x:Key="ThemeBorderMidBrush" Color="{StaticResource ThemeBorderMidColor}" />
                </ResourceDictionary>
                <ResourceDictionary x:Key="Dark">
                  <Color x:Key="ThemeBorderMidColor">#FF808080</Color>
                  <SolidColorBrush x:Key="ThemeBorderMidBrush" Color="{StaticResource ThemeBorderMidColor}" />
                </ResourceDictionary>
              </ResourceDictionary.ThemeDictionaries>
            </ResourceDictionary>
          </Grid.Resources>

          <Label Name="GBHeaderText"
                Margin="5,1" Padding="5,0"
                Content="{TemplateBinding Header}"
                FontWeight="{TemplateBinding FontWeight}" />
          <Border Name="GBBorder"
                  Grid.RowSpan="2" Grid.ColumnSpan="2"
                  BorderBrush="{DynamicResource ThemeBorderMidBrush}"
                  BorderThickness="{TemplateBinding BorderThickness}" 
                  CornerRadius="{TemplateBinding CornerRadius}"
                  RenderOptions.EdgeMode="Aliased">
            <Border.Clip>
              <MultiBinding Converter="{x:Static conv:StaticConverters.ConvertBoundsToOuterBorder}">
                <!--  Parent  -->
                <Binding Path="#GBGrid.Bounds" />
                <!--  Header; Exclude from parent geometry  -->
                <Binding Path="#GBHeaderText.Bounds" />
                <!--  apply offset of inverse of Margins' Left, Top  -->
                <Binding Converter="{x:Static conv:StaticConverters.ThicknessRectConverter}" Path="#GBBorder.Margin" />
              </MultiBinding>
            </Border.Clip>
            <Border.Padding>
              <MultiBinding Converter="{x:Static conv:StaticConverters.ConvertDoublesToThickness}">
                <Binding Source="{StaticResource GBBorderPadding}" />
                <Binding Converter="{x:Static conv:StaticConverters.BoundsToHeaderHeightDividedByTwo}" Path="#GBHeaderText.Bounds" />
                <Binding Source="{StaticResource GBBorderPadding}" />
                <Binding Source="{StaticResource GBBorderPadding}" />
              </MultiBinding>
            </Border.Padding>
            <Border.Margin>
              <MultiBinding Converter="{x:Static conv:StaticConverters.ConvertDoublesToThickness}">
                <Binding Source="{StaticResource GBBorderMargin}" />
                <Binding Converter="{x:Static conv:StaticConverters.BoundsToHeaderHeightDividedByTwo}" Path="#GBHeaderText.Bounds" />
                <Binding Source="{StaticResource GBBorderMargin}" />
                <Binding Source="{StaticResource GBBorderMargin}" />
              </MultiBinding>
            </Border.Margin>

            <ContentPresenter Name="PART_ContentPresenter"
                              Content="{TemplateBinding Content}"
                              RenderOptions.EdgeMode="Antialias" />
          </Border>
        </Grid>
      </ControlTemplate>
    </Setter>
  </ControlTheme>
</ResourceDictionary>

StaticConverters.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using Avalonia;
using Avalonia.Data;
using Avalonia.Data.Converters;
using Avalonia.Media;

namespace FoundationLibrary.Controls
{
    static class StaticConverters
    {
        public static FuncMultiValueConverter<Rect?, CombinedGeometry> ConvertBoundsToOuterBorder { get; } =
        new(rects =>
        {
            List<Rect> arr = rects.Cast<Rect>().ToList() ?? throw new NullReferenceException();
            return arr.Count < 3
                ? throw new ArgumentOutOfRangeException(nameof(rects), "Amount of given Bounds was less than 3")
                : new CombinedGeometry(
                    GeometryCombineMode.Exclude,
                    new RectangleGeometry(arr[0]),
                    new RectangleGeometry(arr[1]),
                    new TranslateTransform(-arr[2].Left, -arr[2].Top)
                );
        });

        /// <summary>
        /// Disguise a Thickness (e.g. Margin) as a Rect. The Rect's Left, Right, Top, and Bottom are equal to the Thickness's properties.
        /// </summary>
        public static FuncValueConverter<Thickness?, Rect> ThicknessRectConverter { get; } =
        new(thickness =>
        {
            if (thickness is Thickness thick)
                return new Rect(thick.Left, thick.Top, thick.Right - thick.Left, thick.Top - thick.Bottom);

            throw new InvalidCastException();
        });
        public static FuncValueConverter<OperatingSystem?, CornerRadius> OSBorderCornerRadius { get; } = new((OperatingSystem? osVersion) =>
            new(osVersion?.Platform switch
            {
                PlatformID.Win32NT => osVersion.Version.Major switch
                {
                    /* check radius via Windows' presentationsettings.exe */

                    // XP and older. XP may have used 3, but older ones were probably 0.
                    5 => 0,
                    6 => osVersion.Version.Minor switch
                    {
                        // Vista, 7 are 3
                        0 or 1 => 3,
                        // 8, 8.1 are...unknown
                        _ => 0,
                    },
                    // 10 and later. My copies of Win11 use 0.
                    10 => osVersion.Version.Build switch
                    {
                        var win11 when win11 >= 22000 => 0,
                        _ => 0,
                    },
                    _ => 0,
                },
                _ => 0
            }));

        public static FuncMultiValueConverter<object?, Thickness> ConvertDoublesToThickness { get; } = new(src =>
        {
            List<double> doubles = new();
            foreach (var nd in src)
            {
                if (nd is double d)
                    doubles.Add(d);
                else throw new InvalidCastException();
            }
            return doubles.Count switch
            {
                1 => new Thickness(doubles[0]),
                2 => new Thickness(doubles[0], doubles[1]),
                4 => new Thickness(doubles[0], doubles[1], doubles[2], doubles[3]),
                _ => throw new IndexOutOfRangeException("Source data must be doubles. Thickness' constructors only allow for 1, 2, or 4 arguments"),
            };
        });

        public static FuncValueConverter<Rect?, double> BoundsToHeaderHeightDividedByTwo { get; } = new(rect =>
        rect.HasValue ? rect.Value.Height / 2 : throw new InvalidCastException());
    }
}

This is source code: https://github.com/alvahtin/TestGroupBox

[alvahtin]

I found the problem.

<Border Name="GBBorder"
                 Grid.RowSpan="2" Grid.ColumnSpan="2"
                 BorderBrush="{DynamicResource ThemeBorderMidBrush}"
                 BorderThickness="{TemplateBinding BorderThickness}" 
                 CornerRadius="{TemplateBinding CornerRadius}"
                 RenderOptions.EdgeMode="Aliased">

I here disabled antialiasing, but I enable it in ContentPresenter:

<ContentPresenter Name="PART_ContentPresenter"
                              Content="{TemplateBinding Content}"
                              RenderOptions.EdgeMode="Antialias" />

I forgot why I did this. Maybe so that the borders of Border are not blurred. But in 11.0 this code did not cause problems, but in 11.1 it came up.