Generate a list of glyph names or a C# constants file from a font

dump-cmap.py

#! /usr/bin/env python3

# Use this to generate a list of glyph names from a font to a 
# text file. This can be passed to pyftsubset to generate a
# small font.
# This can also generate a C# constants class from the font
# Usage:
# dump-cmap.py fontfile.ttf glyphlist.txt
# or
# dump-cmap.py fontfile.ttf constants.cs fontname namespace
#
# To create a small ttf file, use the following syntax
# pyftsubset fontfile.ttf --output-file=newfont.ttf --glyph-names --glyphs-file=glyphlist.txt
#
# This requires fonttools
# intall with pip
# pip imstall fonttools
#
# See https://gist.github.com/anotherlab/6a1198ee247e961882b09c40efb43c5f
# for script to collect glyphs used by a Xamarin.Forms or .NET MAUI project

from fontTools.ttLib import TTFont
import sys

def MakeGlyphNamesFile(glyphs, glyphNamesFile):
    file1 = open(glyphNamesFile, "w+")
    for glyph in glyphs:
        file1.write(glyph+'\n')
    file1.close()
    return    

def GlyphNameToDotNet(glyphname):
    lst = glyphname.split('-')
    newName = ''
    for n in lst:
        newName += n.capitalize()

    return newName

def PythonHexToDotNet(code):
    newCode = f'{code:08x}'
    return newCode

def MakeDotNet(dic, fName, fontName, nameSpace):
    file1 = open(fName, "w+")
    file1.write('namespace ' + nameSpace + '\n')
    file1.write('{\n')
    file1.write('  public static class ' + fontName+ '\n')
    file1.write('  {\n')
    for glyph in dic:
        file1.write('    public const string ' + GlyphNameToDotNet(glyph) + ' = "\\U' +  PythonHexToDotNet(dic[glyph]) + '";\n')
    file1.write('  }\n')
    file1.write('}\n')
    file1.close()
    return    

if len(sys.argv) < 3:
	print("Usage:")
	print("dump-cmap.py fontfile.ttf glyphlist.txt")
	print("or")
	print("dump-cmap.py fontfile.ttf constants.cs fontname namespace")
	sys.exit(1)

glyphNamesFile = '-'
classFile = '-'
fontName = '-'
nameSpace = '-'

print(len(sys.argv))

fontfile = sys.argv[1]

if (len(sys.argv) == 5):
    classFile = sys.argv[2]
    fontName = sys.argv[3]
    nameSpace = sys.argv[4]

if (len(sys.argv) == 2):
    glyphNamesFile = sys.argv[2]

font = TTFont(fontfile)

cmap = font['cmap']

glyphs = {}

for table in cmap.tables:
    if table.format in [12]:
        for code, name in table.cmap.items():
            glyphs[name] = code

if  glyphNamesFile != '-':
    MakeGlyphNamesFile(glyphs, glyphNamesFile)

if classFile != '-':
    if fontName != '-':
        if nameSpace != '-':
            MakeDotNet(glyphs, classFile, fontName, nameSpace)