def add_gsub_to_font(fontfile):
"""Adds an empty GSUB table to a font."""
font = ttLib.TTFont(fontfile)
gsub_table = ttLib.getTableClass('GSUB')('GSUB')
gsub_table.table = otTables.GSUB()
gsub_table.table.Version = 1.0
gsub_table.table.ScriptList = otTables.ScriptList()
gsub_table.table.ScriptCount = 1
gsub_table.table.LookupList = otTables.LookupList()
gsub_table.table.LookupList.LookupCount = 0
gsub_table.table.LookupList.Lookup = []
gsub_table.table.FeatureList = otTables.FeatureList()
gsub_table.table.FeatureList.FeatureCount = 0
gsub_table.table.LookupList.FeatureRecord = []
script_record = otTables.ScriptRecord()
script_record.ScriptTag = get_opentype_script_tag(fontfile)
script_record.Script = otTables.Script()
script_record.Script.LangSysCount = 0
script_record.Script.LangSysRecord = []
default_lang_sys = otTables.DefaultLangSys()
default_lang_sys.FeatureIndex = []
default_lang_sys.FeatureCount = 0
default_lang_sys.LookupOrder = None
default_lang_sys.ReqFeatureIndex = 65535
script_record.Script.DefaultLangSys = default_lang_sys
gsub_table.table.ScriptList.ScriptRecord = [script_record]
font['GSUB'] = gsub_table
target_file = tempfile.gettempdir() + '/' + os.path.basename(fontfile)
font.save(target_file)
return target_file
def create_script_list(script_tag='DFLT'):
"""Create a ScriptList for the GSUB table."""
def_lang_sys = otTables.DefaultLangSys()
def_lang_sys.ReqFeatureIndex = 0xFFFF
def_lang_sys.FeatureCount = 1
def_lang_sys.FeatureIndex = [0]
def_lang_sys.LookupOrder = None
script_record = otTables.ScriptRecord()
script_record.ScriptTag = script_tag
script_record.Script = otTables.Script()
script_record.Script.DefaultLangSys = def_lang_sys
script_record.Script.LangSysCount = 0
script_record.Script.LangSysRecord = []
script_list = otTables.ScriptList()
script_list.ScriptCount = 1
script_list.ScriptRecord = [script_record]
return script_list