GSUB: Glyph Substitution table

The GSUB table is an OpenType table.

class fontTools.ttLib.tables.G_S_U_B_.table_G_S_U_B_(tag=None)[source]

Bases: BaseTTXConverter

Glyph Substitution table

The GSUB table contains glyph-substitution rules used in OpenType Layout.

See also https://learn.microsoft.com/en-us/typography/opentype/spec/gsub

closure_glyphs(s)
merge(m, tables)
mergeMap = {'table': <function mergeObjects>, 'tableTag': <function onlyExisting.<locals>.wrapper>}
neuter_lookups(lookup_indices)

Sets lookups not in lookup_indices to None.

prune_features()

Remove unreferenced features

prune_lookups(remap=True)

Remove (default) or neuter unreferenced lookups

prune_post_subset(font, options)
prune_pre_subset(font, options)
remove_redundant_langsys()
retain_empty_scripts()
subset_feature_tags(feature_tags)
subset_glyphs(s)
subset_lookups(lookup_indices)

Retains specified lookups, then removes empty features, language systems, and scripts.

subset_script_tags(tags)