Struct zng::font::FontMetrics

pub struct FontMetrics {
    pub size_scale: f32,
    pub ascent: Px,
    pub descent: Px,
    pub line_gap: Px,
    pub underline_position: Px,
    pub underline_thickness: Px,
    pub cap_height: Px,
    pub x_height: Px,
    pub bounds: Rect<Px, Px>,
}

Various metrics about a Font.

You can compute these metrics from a FontFaceMetrics

Fields

size_scale: f32

Multiply this to a font EM value to get the size in pixels.

ascent: Px

The maximum amount the font rises above the baseline, in pixels.

descent: Px

The maximum amount the font descends below the baseline, in pixels.

This is typically a negative value to match the definition of sTypoDescender in the OS/2 table in the OpenType specification. If you are used to using Windows or Mac APIs, beware, as the sign is reversed from what those APIs return.

line_gap: Px

Distance between baselines, in pixels.

underline_position: Px

The suggested distance of the top of the underline from the baseline (negative values indicate below baseline), in pixels.

underline_thickness: Px

A suggested value for the underline thickness, in pixels.

cap_height: Px

The approximate amount that uppercase letters rise above the baseline, in pixels.

x_height: Px

The approximate amount that non-ascending lowercase letters rise above the baseline, in pixels.

bounds: Rect<Px, Px>

A rectangle that surrounds all bounding boxes of all glyphs, in pixels.

This corresponds to the xMin/xMax/yMin/yMax values in the OpenType head table.

Implementations

impl FontMetrics

pub fn line_height(&self) -> Px

The font line height.

Trait Implementations

impl Clone for FontMetrics

fn clone(&self) -> FontMetrics

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FontMetrics

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for FontMetrics

fn deserialize<__D>( __deserializer: __D, ) -> Result<FontMetrics, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for FontMetrics

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.