Struct Typeface 

pub struct Typeface(/* private fields */);

A font loaded for text at one location in its design space, with the family names, weight and style text chooses it by: Compose’s Typeface. Clones share one load; two typefaces are equal when they draw the same glyphs, from the same bytes at the same axis positions.

Implementations

impl Typeface

pub fn from_bytes(bytes: impl Into<FontBytes>) -> Result<Self, TypefaceError>

Reads bytes as a typeface no family was declared for: its weight, style and family names come from the font.

pub fn from_registered( family: &FontFamily, weight: FontWeight, style: FontStyle, bytes: impl Into<FontBytes>, variations: &[([u8; 4], f32)], ) -> Result<Self, TypefaceError>

Reads bytes as a typeface an app registered under family, declaring weight and style for it, as a Compose Font(resId, weight, style) entry does: the declaration wins over the font’s own values, and a variable font is instanced on its wght, ital and slnt axes, so one file backs a whole family. The explicit variations then win over the declared positions; a variation of an axis the font lacks, or outside that axis’s range, fails.

pub fn family_names(&self) -> &[String]

The family names the font’s name table gives it, typographic family first.

pub fn registered_family(&self) -> Option<FontFamilyKey>

The family the typeface was registered under, None for one read with Typeface::from_bytes.

pub fn weight(&self) -> FontWeight

The weight text chooses the typeface by.

pub fn style(&self) -> FontStyle

The style text chooses the typeface by.

pub fn is_color(&self) -> bool

Whether the font draws glyphs in color (a COLR, CBDT, sbix or SVG table), as emoji fonts do.

pub fn synthesis( &self, weight: FontWeight, style: FontStyle, synthesis: FontSynthesis, ) -> Synthesis

What Compose synthesizes for text in weight and style drawn with this typeface, as synthesis allows: a bold for a weight of 600 or more when the typeface draws none that heavy, and an italic when it draws none.

pub fn variations(&self) -> &[([u8; 4], f32)]

The axis positions the typeface is instanced at, sorted by tag.

pub fn content_hash(&self) -> u64

A hash of the font’s bytes and its axis positions: equal for two loads of one instance.

pub fn units_per_em(&self) -> u16

The font’s design units in an em.

pub fn line_metrics(&self) -> LineMetrics

The font’s line metrics at the instance, in design units: the typographic line when the font asks for it with USE_TYPO_METRICS, otherwise the hhea line, as Skia and FreeType read them.

pub fn decoration_metrics(&self) -> DecorationMetrics

Where the font draws an underline and a line through its text, in design units: its post underline and OS/2 strikeout, or Skia’s defaults for a font without them.

pub fn glyph(&self, ch: char) -> Option<GlyphId>

The glyph the font maps ch to, None when it has none.

pub fn covers(&self, ch: char) -> bool

Whether the font maps ch to a glyph.

pub fn advance(&self, glyph: GlyphId) -> f32

The horizontal advance of glyph at the instance, in design units.

Trait Implementations

impl Clone for Typeface

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Typeface

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Typeface

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.