noto-emoji/map_pua_emoji.py

79 lines
2.3 KiB
Python

#!/usr/bin/env python3
#
# Copyright 2014 Google Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Modify an emoji font to map legacy PUA characters to standard ligatures."""
__author__ = 'roozbeh@google.com (Roozbeh Pournader)'
import sys
import itertools
from fontTools import ttLib
from nototools import font_data
import add_emoji_gsub
def get_glyph_name_from_gsub(char_seq, font):
"""Find the glyph name for ligature of a given character sequence from GSUB.
"""
cmap = font_data.get_cmap(font)
# FIXME: So many assumptions are made here.
try:
first_glyph = cmap[char_seq[0]]
rest_of_glyphs = [cmap[ch] for ch in char_seq[1:]]
except KeyError:
return None
for lookup in font['GSUB'].table.LookupList.Lookup:
ligatures = lookup.SubTable[0].ligatures
try:
for ligature in ligatures[first_glyph]:
if ligature.Component == rest_of_glyphs:
return ligature.LigGlyph
except KeyError:
continue
return None
def add_pua_cmap_to_font(font):
cmap = font_data.get_cmap(font)
for pua, (ch1, ch2) in itertools.chain(
add_emoji_gsub.EMOJI_KEYCAPS.items(), add_emoji_gsub.EMOJI_FLAGS.items()
):
if pua not in cmap:
glyph_name = get_glyph_name_from_gsub([ch1, ch2], font)
if glyph_name is not None:
cmap[pua] = glyph_name
def add_pua_cmap(source_file, target_file):
"""Add PUA characters to the cmap of the first font and save as second."""
font = ttLib.TTFont(source_file)
add_pua_cmap_to_font(font)
font.save(target_file)
def main(argv):
"""Save the first font given to the second font."""
add_pua_cmap(argv[1], argv[2])
if __name__ == '__main__':
main(sys.argv)