Struct LineHeight

Namespace

Egami.Fonts.Layout

Assembly

Egami.Fonts.dll

The height a run asks of its line box (CSS line-height): Normal from the font's metrics, a Multiple(float) of the font size or an Absolute(float) height. The extra over the font's ascent and descent is split half above and half below.

public readonly record struct LineHeight : IEquatable<LineHeight>

Implements

IEquatable<LineHeight>

Inherited Members

ValueType.Equals(object)

ValueType.GetHashCode()

ValueType.ToString()

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Examples

// Font families come from a collection; later families cover what the first lacks.
FontCollection fonts = new();
fonts.AddFile(System.IO.Path.Combine(folder, "NotoSans-Regular.ttf"));
fonts.AddFile(System.IO.Path.Combine(folder, "NotoSansArabic-Regular.ttf"));
fonts.TryGetFamily("Noto Sans", out FontFamily latin);
fonts.TryGetFamily("Noto Sans Arabic", out FontFamily arabic);

// Styles nest: the inner span keeps the outer one's size and adds a color and an underline.
RichText text = new RichTextBuilder()
    .Append("Peace is ")
    .Push(new TextStyle { Size = 20 })
    .Append("\u0633\u0644\u0627\u0645 ")
    .Push(new TextStyle { Color = new Rgba8(200, 30, 30, 255), Decoration = new TextDecoration() })
    .Append("in Arabic")
    .Pop()
    .Pop()
    .AddPlaceholder(new Placeholder(16, 16, PlaceholderAlignment.Middle))
    .ToRichText();

ParagraphStyle style = new()
{
    DefaultStyle = new TextStyle { FontFamilies = [latin, arabic], Size = 16, LineHeight = LineHeight.Multiple(1.4f) },
    Align = TextAlign.Justify,
    LineBreaking = new LineBreakOptions(WordBreak: WordBreak.Normal),
};

// Shaped once: lay it out at any width later.
Paragraph paragraph = Paragraph.Create(text, style);

Properties

Kind

Gets how the height is given.

public LineHeightKind Kind { get; }

Property Value

LineHeightKind

Normal

Gets the font's own line height: its ascent, descent and line gap.

public static LineHeight Normal { get; }

Property Value

LineHeight

Value

Gets the multiple of the font size, or the height in canvas units; 0 for Normal.

public float Value { get; }

Property Value

float

Methods

Absolute(float)

A height in canvas units.

public static LineHeight Absolute(float height)

Parameters

height float

The height, 0 or more.

Returns

LineHeight

The line height.

Exceptions

ArgumentOutOfRangeException

height is negative or not finite.

Multiple(float)

A height that is a multiple of the font size, as CSS's unitless line-height.

public static LineHeight Multiple(float factor)

Parameters

factor float

The multiple, 0 or more.

Returns

LineHeight

The line height.

Exceptions

ArgumentOutOfRangeException

factor is negative or not finite.