Struct harfbuzz_rs::Feature

#[repr(transparent)]pub struct Feature(_);

A feature tag with an accompanying range specifying on which subslice of shapes input it should be applied.

You can pass a slice of Features to shape that will be activated for the corresponding slices of input.

Examples

Shape some text using the calt (Contextual Alternatives) feature.

use harfbuzz_rs::{Face, Font, UnicodeBuffer, shape, Feature, Tag};

let path = "testfiles/SourceSansVariable-Roman.ttf";
let face = Face::from_file(path, 0).expect("could not load face");
let font = Font::new(face);

let buffer = UnicodeBuffer::new().add_str("Hello World!");

// contextual alternatives feature
let feature_tag = b"calt";

// use the feature on the entire input
let feature_range = 0..;
let feature = Feature::new(feature_tag, 0, feature_range);

let output = shape(&font, buffer, &[feature]);

Implementations

impl Feature

pub fn new(
    tag: impl Into<Tag>,
    value: u32,
    range: impl RangeBounds<usize>
) -> Feature

Create a new Feature struct.

The feature will be applied with the given value to all glyphs which are in clusters contained in range.

Arguments

• tag: The OpenType feature tag to use.
• value: Some OpenType features accept different values to change their behaviour.
• range: The cluster range that should be affected by this feature.

pub fn tag(&self) -> Tag

pub fn value(&self) -> u32

pub fn start(&self) -> usize

pub fn end(&self) -> usize

Trait Implementations

impl Clone for Feature

fn clone(&self) -> Feature

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Copy for Feature

impl Debug for Feature

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

Formats the value using the given formatter.