Editing a variable TTF

Glyphs
1

Hi there,

I’m trying to edit a variable TTF font and add additional instances.

However, when I open the file in Glyphs, I run into a couple of issues:
• Kerning pairs seem to be missing
• Diacritics are misplaced
• It looks like anchors might be gone as well

From what I understand, this might be due to the limitations of working with a compiled TTF rather than the original source file.

What would be the best approach to:

  1. Properly recover or reconstruct the font data (kerning, anchors, etc.)
  2. Add new instances to a variable font in this situation

Would it be better to convert the font to a different format first or?

Any advice or recommended workflows would be much appreciated.

Thanks!

2

Are you only looking to add extra instances, nothing else? I would say that the cleanest way would be to add extra entries in the fvar, STAT and name table. You can do this with TTX, or OTMaster.

What VF are you editing? If this is an open-source project, you should definitely use the source files (Glyphs/UFO/VFB…). If it isn’t, are you sure you’re allowed to edit the font?

3

Thank you for the quick answer @SCarewe
Yes I only want to add extra instances at this point so I’ll try TTX.
It’s Google Sans Flex which is under the Open Font License but the source files is not yet public unfortunately.