Enum SubstitutionLookup

pub enum SubstitutionLookup<'a> {
    Single(Lookup<'a, SingleSubst<'a>>),
    Multiple(Lookup<'a, MultipleSubstFormat1<'a>>),
    Alternate(Lookup<'a, AlternateSubstFormat1<'a>>),
    Ligature(Lookup<'a, LigatureSubstFormat1<'a>>),
    Contextual(Lookup<'a, SubstitutionSequenceContext<'a>>),
    ChainContextual(Lookup<'a, SubstitutionChainContext<'a>>),
    Extension(Lookup<'a, ExtensionSubtable<'a>>),
    Reverse(Lookup<'a, ReverseChainSingleSubstFormat1<'a>>),
}

A GSUB Lookup subtable.

Variants

Single(Lookup<'a, SingleSubst<'a>>)

Multiple(Lookup<'a, MultipleSubstFormat1<'a>>)

Alternate(Lookup<'a, AlternateSubstFormat1<'a>>)

Ligature(Lookup<'a, LigatureSubstFormat1<'a>>)

Contextual(Lookup<'a, SubstitutionSequenceContext<'a>>)

ChainContextual(Lookup<'a, SubstitutionChainContext<'a>>)

Extension(Lookup<'a, ExtensionSubtable<'a>>)

Reverse(Lookup<'a, ReverseChainSingleSubstFormat1<'a>>)

Implementations

impl<'a> SubstitutionLookup<'a>

pub fn lookup_flag(&self) -> LookupFlag

pub fn lookup_type(&self) -> u16

Different enumerations for GSUB and GPOS

pub fn mark_filtering_set(&self) -> Option<u16>

pub fn subtables(&self) -> Result<SubstitutionSubtables<'a>, ReadError>

Return the subtables for this lookup.

This method handles both extension and non-extension lookups, and saves the caller needing to dig into the SubstitutionLookup enum itself.

Trait Implementations

impl<'a> FontRead<'a> for SubstitutionLookup<'a>

fn read(bytes: FontData<'a>) -> Result<Self, ReadError>

Read an instance of Self from the provided data, performing validation.