minacle/subfont

generate subsetted woff/woff2 font.

subfont's Issues

Crashed with fontTools.ttLib.TTLibError: specify a font number between 0 and 27 (inclusive)

Trying to use the script against a SVG(intentionally), it crashes with this error:

python3.6 subfont.py -f ~/.local/share/fonts/Adobe\ -\ Source\ Han\ Serif\ 思源宋體\ -\ 開放來源碼的泛\ CJK\ 字體/SourceHanSerif.ttc --output-directory . -- ~/工作空間/社群/台灣在地化社群/臺灣在地化社群的標誌/來源碼/l10n-tw-logo.svg                                                                                  
found 0 characters.                                                                                                                                          
Traceback (most recent call last):                                                                                                                           
  File "/usr/local/bin/pyftsubset", line 11, in <module>                                                                                                     
    sys.exit(main())                                                                                                                                         
  File "/usr/local/lib/python3.6/dist-packages/fontTools/misc/loggingTools.py", line 372, in wrapper                                                         
    return func(*args, **kwds)                                                                                                                               
  File "/usr/local/lib/python3.6/dist-packages/fontTools/subset/__init__.py", line 2954, in main                                                             
    font = load_font(fontfile, options, dontLoadGlyphNames=dontLoadGlyphNames)                                                                               
  File "/usr/local/lib/python3.6/dist-packages/fontTools/misc/loggingTools.py", line 372, in wrapper                                                         
    return func(*args, **kwds)                                                                                                                               
  File "/usr/local/lib/python3.6/dist-packages/fontTools/subset/__init__.py", line 2801, in load_font                                                        
    lazy=lazy)                                                                                                                                               
  File "/usr/local/lib/python3.6/dist-packages/fontTools/ttLib/__init__.py", line 180, in __init__
    self.reader = sfnt.SFNTReader(file, checkChecksums, fontNumber=fontNumber)
  File "/usr/local/lib/python3.6/dist-packages/fontTools/ttLib/sfnt.py", line 62, in __init__
    raise ttLib.TTLibError("specify a font number between 0 and %d (inclusive)" % (self.numFonts - 1))
fontTools.ttLib.TTLibError: specify a font number between 0 and 27 (inclusive)
generation failed ~/.local/share/fonts/Adobe - Source Han Serif 思源宋體 - 開放來源碼的泛 CJK 字體/SourceHanSerif.ttc

subfont.py: error: the following arguments are required: FILE

Is it possible to make this argument optional?
It would be nice to use all characters if FILE is not provided.

Another improvement could be to support also chars instead of argument:
python subfont.py -f MyFont.ttf -- "abcdefghijklmnopqrstuvwxyz0123456789"