c# - TextBlock as big as a capital letter (ignoring font ascender/descender)

Question

I am looking to get a specific behavior on TextBlock so that its height only includes the height of the capital letters (from baseline to top minus "ascender height"). Please see the image Sphinx from Wikipedia to see what I mean. Also the image below may indicate better what I am after.

I am not specifically looking for a pure XAML solution (probably impossible) so a C# code behind (a converter) is also fine.

This is the XAML used in XamlPad to produce the left A in the image above.

<TextBlock Text="A" Background="Aquamarine" FontSize="120" HorizontalAlignment="Center" VerticalAlignment="Center" />

Answer 1

u can try to use attribute LineStackingStrategy="BlockLineHeight" and a Converter on the LineHeight attributes and a converter on the Height of TextBlock. This a sample code of converters

// Height Converter
public class FontSizeToHeightConverter : IValueConverter
{
    public static double COEFF = 0.715;
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        return (double)value * COEFF;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}
// LineHeightConverter
public class FontSizeToLineHeightConverter : IValueConverter
{
    public static double COEFF = 0.875;
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        return double.Parse(value.ToString()) * COEFF;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

The Coefficient used on converters depends on Used Family Fonts (Baseline and LineSpacing):

<TextBlock Text="ABC" Background="Aqua" LineStackingStrategy="BlockLineHeight" 
FontSize="{Binding ElementName=textBox1, Path=Text}" 
FontFamily="{Binding ElementName=listFonts, Path=SelectedItem}" 
Height="{Binding RelativeSource={RelativeSource Self}, Path=FontSize, Mode=OneWay, Converter={StaticResource FontSizeToHeightConverter1}}"
LineHeight="{Binding RelativeSource={RelativeSource Self}, Path=FontSize, Converter={StaticResource FontSizeToLineHeightConverter}}"/>

The best solution is to find how to calculate the Coeff based on parameters Baseline and LineSpacing of the FontFamily. In this sample (Segeo UI) the Coeff of Height = 0.715 and LineHeight = 0,875 * FontSize.