Enum SelectedGvar 

pub enum SelectedGvar<'a> {
    Original(Gvar<'a>),
    Extended(GvarExtended<'a>),
}

Glyph variations from GVAR or the original gvar table.

Variants

Original(Gvar<'a>)

The original gvar table.

Extended(GvarExtended<'a>)

The GVAR table (ISO/IEC 14496-22:2026).

Implementations

impl SelectedGvar<'_>

pub fn simple_deltas<C, D>( &self, glyph_id: GlyphId, coords: &[F2Dot14], points: &[Point<C>], flags: &mut [PointFlags], contours: &[u16], buffers: &mut DeltaBuffers<'_, D>, ) -> Option<bool>

where C: PointCoord, D: PointCoord + From<C>,

Computes the deltas for the points of a simple glyph at the given location in variation space.

Looks the glyph’s variation data up and hands off to GlyphVariationData::simple_deltas, which documents the arguments.

Returns true if the glyph has variation data, and false if it does not — in which case the deltas are zeroed. Note that they are zeroed whichever it returns, so they never retain values from a previous call.

pub fn simple_deltas_with_scalars<C, D>( &self, glyph_id: GlyphId, coords: &[F2Dot14], scalars: &[Fixed], points: &[Point<C>], flags: &mut [PointFlags], contours: &[u16], buffers: &mut DeltaBuffers<'_, D>, ) -> Option<bool>

where C: PointCoord, D: PointCoord + From<C>,

Computes the deltas for the points of a simple glyph, reusing scalars.

scalars holds one entry per shared tuple, from Gvar::compute_scalars. It may be empty or cover only some of them; the rest are computed here.

pub fn composite_deltas<D: PointCoord>( &self, glyph_id: GlyphId, coords: &[F2Dot14], deltas: &mut [Point<D>], ) -> Option<bool>

Computes the deltas for the component offsets of a composite glyph at the given location in variation space.

Looks the glyph’s variation data up and hands off to GlyphVariationData::composite_deltas.

deltas must have one entry per component plus four for the phantom points.

Returns true if the glyph has variation data, and false if it does not — in which case deltas is zeroed.

pub fn composite_deltas_with_scalars<D: PointCoord>( &self, glyph_id: GlyphId, coords: &[F2Dot14], scalars: &[Fixed], deltas: &mut [Point<D>], ) -> Option<bool>

Computes the deltas for a composite glyph’s component offsets, reusing scalars.

scalars holds one entry per shared tuple, from Gvar::compute_scalars. It may be empty or cover only some of them; the rest are computed here.

impl<'a> SelectedGvar<'a>

pub fn glyph_count(&self) -> u32

Returns the number of glyphs with variation data.

fn is_extended(&self) -> bool

pub fn version(&self) -> MajorMinor

Returns version from the selected table.

pub fn axis_count(&self) -> u16

Returns axis_count from the selected table.

pub fn shared_tuple_count(&self) -> u16

Returns shared_tuple_count from the selected table.

pub fn shared_tuples_offset(&self) -> Offset32

Returns shared_tuples_offset from the selected table.

pub fn flags(&self) -> GvarFlags

Returns flags from the selected table.

pub fn glyph_variation_data_array_offset(&self) -> u32

Returns glyph_variation_data_array_offset from the selected table.

pub fn glyph_variation_data_offsets(&self) -> ComputedArray<'a, U16Or32>

Returns glyph_variation_data_offsets from the selected table.

pub fn offset_data(&self) -> FontData<'a>

Returns offset_data from the selected table.

impl<'a> SelectedGvar<'a>

pub fn shared_tuples(&self) -> Result<SharedTuples<'a>, ReadError>

Returns the shared tuples, including an empty array when both the count and offset are zero.

pub fn data_for_gid( &self, gid: GlyphId, ) -> Result<Option<FontData<'a>>, ReadError>

Return the raw data for this gid.

If there is no variation data for the glyph, returns Ok(None).

pub fn glyph_variation_data_for_range( &self, offset_range: Range<usize>, ) -> Result<FontData<'a>, ReadError>

pub fn as_bytes(&self) -> &[u8]

fn data_range_for_gid(&self, gid: GlyphId) -> Result<Range<usize>, ReadError>

pub fn glyph_variation_data( &self, gid: GlyphId, ) -> Result<Option<GlyphVariationData<'a>>, ReadError>

Get the variation data for a specific glyph.

Returns Ok(None) if there is no variation data for this glyph, and returns an error if there is data but it is malformed.

pub fn compute_scalars(&self, coords: &[F2Dot14], out: &mut [Fixed]) -> usize

Returns the phantom point deltas for the given variation coordinates and glyph identifier, if variation data exists for the glyph.

The resulting array will contain four deltas: [left, right, top, bottom]. Computes the scalar for each shared tuple at coords, in table order, and returns how many were written.

A tuple that does not apply at coords is written as zero, which is the value it contributes. Only the peak is used: a glyph naming a shared tuple may state its own range alongside it, and that range is not shared.

out may be shorter than the table has shared tuples, and an unreadable table writes nothing. A reader computes whatever is missing.

pub fn phantom_point_deltas( &self, glyf: &Glyf<'_>, loca: &Loca<'_>, coords: &[F2Dot14], glyph_id: GlyphId, ) -> Option<[Point<Fixed>; 4]>

pub fn phantom_point_deltas_with_scalars( &self, glyf: &Glyf<'_>, loca: &Loca<'_>, coords: &[F2Dot14], scalars: &[Fixed], glyph_id: GlyphId, ) -> Option<[Point<Fixed>; 4]>

Returns the phantom point deltas for glyph_id at coords, reusing scalars.

scalars holds one entry per shared tuple, from compute_scalars. It may be empty or cover only some of them; the rest are computed here.

Trait Implementations

impl<'a> Clone for SelectedGvar<'a>

fn clone(&self) -> SelectedGvar<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> From<Gvar<'a>> for SelectedGvar<'a>

fn from(table: Gvar<'a>) -> Self

Converts to this type from the input type.

impl<'a> From<GvarExtended<'a>> for SelectedGvar<'a>

fn from(table: GvarExtended<'a>) -> Self

Converts to this type from the input type.