def _add_feature(self, font: Font, table: otTables.GPOS, feature_tag: str,
lookup_indices: List[int]) -> None:
logger.debug('Adding "%s" to: "%s" %s', feature_tag, font,
self._to_str(glyph_ids=True))
assert not Font._has_ottable_feature(table, feature_tag)
features = table.FeatureList.FeatureRecord
feature_index = len(features)
logger.info('Adding Feature "%s" at index %d for lookup %s',
feature_tag, feature_index, lookup_indices)
feature_record = otTables.FeatureRecord()
feature_record.FeatureTag = feature_tag
feature_record.Feature = otTables.Feature()
feature_record.Feature.LookupListIndex = lookup_indices
feature_record.Feature.LookupCount = len(lookup_indices)
features.append(feature_record)
scripts = table.ScriptList.ScriptRecord
for script_record in scripts:
default_lang_sys = script_record.Script.DefaultLangSys
if default_lang_sys:
logger.debug(
"Adding Feature index %d to script '%s' DefaultLangSys",
feature_index, script_record.ScriptTag)
default_lang_sys.FeatureIndex.append(feature_index)
for lang_sys in script_record.Script.LangSysRecord:
logger.debug(
"Adding Feature index %d to script '%s' LangSys '%s'",
feature_index, script_record.ScriptTag,
lang_sys.LangSysTag)
lang_sys.LangSys.FeatureIndex.append(feature_index)
def add_to_font(self, font: Font) -> bool:
self.assert_font(font)
self.assert_glyphs_are_disjoint()
if not self._can_add_to_table:
if self._add_glyphs_count:
logger.warning('Skipped because no pairs: "%s"', font)
return False
table = font.gpos_ottable(create=True)
lookups = table.LookupList.Lookup
pos = GlyphSets.PosValues(font, self)
logger.info('Adding Lookups for %dL, %dR, %dM, %dS', len(pos.left),
len(pos.right), len(pos.middle), len(pos.space))
feature_tag = 'vhal' if font.is_vertical else 'halt'
if not Font._has_ottable_feature(table, feature_tag):
lookup_index = self._build_halt_lookup(font, lookups, pos)
self._add_feature(font, table, feature_tag, [lookup_index])
feature_tag = 'vchw' if font.is_vertical else 'chws'
lookup_indices = self._build_chws_lookup(font, lookups, pos)
self._add_feature(font, table, feature_tag, lookup_indices)
return True