Struct Metrics

pub struct Metrics {

    pub units_per_em: u16,
    pub glyph_count: u16,
    pub is_monospace: bool,
    pub italic_angle: f32,
    pub ascent: f32,
    pub descent: f32,
    pub leading: f32,
    pub cap_height: Option<f32>,
    pub x_height: Option<f32>,
    pub average_width: Option<f32>,
    pub max_width: Option<f32>,
    pub underline: Option<Decoration>,
    pub strikeout: Option<Decoration>,
    pub bounds: Option<BoundingBox>,
}

Metrics that apply to all glyphs in a font.

These are retrieved for a specific position in the design space.

This metrics here are derived from the following tables:

• head: units_per_em, bounds
• maxp: glyph_count
• post: is_monospace, italic_angle, underline
• OS/2: average_width, cap_height, x_height, strikeout, as well as the line metrics: ascent, descent, leading if the USE_TYPOGRAPHIC_METRICS flag is set or the hhea line metrics are zero (the Windows metrics are used as a last resort).
• hhea: max_width, as well as the line metrics: ascent, descent, leading if they are non-zero and the USE_TYPOGRAHIC_METRICS flag is not set in the OS/2 table

For variable fonts, deltas are computed using the MVAR table.

Fields

units_per_em: u16

Number of font design units per em unit.

glyph_count: u16

Number of glyphs in the font.

is_monospace: bool

True if the font is not proportionally spaced.

italic_angle: f32

Italic angle in counter-clockwise degrees from the vertical. Zero for upright text, negative for text that leans to the right.

ascent: f32

Distance from the baseline to the top of the alignment box.

descent: f32

Distance from the baseline to the bottom of the alignment box.

leading: f32

Recommended additional spacing between lines.

cap_height: Option<f32>

Distance from the baseline to the top of a typical English capital.

x_height: Option<f32>

Distance from the baseline to the top of the lowercase “x” or similar character.

average_width: Option<f32>

Average width of all non-zero width characters in the font.

max_width: Option<f32>

Maximum advance width of all characters in the font.

underline: Option<Decoration>

Metrics for an underline decoration.

strikeout: Option<Decoration>

Metrics for a strikeout decoration.

bounds: Option<BoundingBox>

Union of minimum and maximum extents for all glyphs in the font.

Implementations

impl Metrics

pub fn new<'a>( font: &impl TableProvider<'a>, size: Size, location: impl Into<LocationRef<'a>>, ) -> Self

Creates new metrics for the given font, size, and location in normalized variation space.

Trait Implementations

impl Clone for Metrics

fn clone(&self) -> Metrics

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Metrics

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

Formats the value using the given formatter.

impl Default for Metrics

fn default() -> Metrics

Returns the “default value” for a type.

impl PartialEq for Metrics

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Metrics

impl StructuralPartialEq for Metrics