Struct GlyphStyleMap

pub(crate) struct GlyphStyleMap {
    styles: Vec<GlyphStyle>,
    metrics_map: [u8; 90],
    metrics_count: u8,
}

Maps glyph identifiers to glyph styles.

Also keeps track of the styles that are actually used so we can allocate an appropriately sized metrics array.

Fields

styles: Vec<GlyphStyle>

List of styles, indexed by glyph id.

metrics_map: [u8; 90]

Maps an actual style class index into a compacted index for the metrics table.

Uses 0xFF to signify unused styles.

metrics_count: u8

Number of metrics styles in use.

Implementations

impl GlyphStyleMap

pub fn new(glyph_count: u32, shaper: &Shaper<'_>) -> Self

Computes a new glyph style map for the given glyph count and character map.

Roughly based on https://gitlab.freedesktop.org/freetype/freetype/-/blob/57617782464411201ce7bbc93b086c1b4d7d84a5/src/autofit/afglobal.c#L126

fn new_inner( glyph_count: u32, shaper: &Shaper<'_>, visited_set: VisitedLookupSet<'_>, ) -> Self

pub fn style(&self, glyph_id: GlyphId) -> Option<GlyphStyle>

pub fn metrics_index(&self, style: GlyphStyle) -> Option<usize>

Returns a compacted metrics index for the given glyph style.

pub fn metrics_count(&self) -> usize

Returns the required size of the compacted metrics array.

pub fn metrics_styles(&self) -> impl Iterator<Item = &'static StyleClass> + '_

Returns an ordered iterator yielding each style class referenced by this map.

fn use_style(&mut self, style_ix: usize)

Trait Implementations

impl Debug for GlyphStyleMap

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

Formats the value using the given formatter.

impl Default for GlyphStyleMap

fn default() -> Self

Returns the “default value” for a type.