gist demo to rename glyphs in .fea data, using feaLib

[justvanrossum]

https://gist.github.com/justvanrossum/1f816294c55abd1e762976702b01e6b7

I could submit this as a Snippet, but it doesn't really have a useful main program. Would it perhaps still be useful as a snippet?

[anthrotype]

nice! I think we could even add this as a method on the feaLib.ast classes.
If you prefer to dump this in the Snippet directory, i'm ok with that too.

One of the reasons ufo2ft does the glyph production names renaming at the end, in its postProcessor, directly manipulating the binary TTFont's post or CFF tables, is because we didn't have a handy way to rename the glyph names in the features.fea.

[anthrotype]

makes sense, yes

[typoman]

FWIW, I wrote a subsetter that you can see in fontgadgets features module. I really want to add it to fonttools, but requires writing a lot of tests. It is based on @anthrotype suggestion to add subset method to ast objects. I also needed extra data during subset, so I add them to feature objects using another parser subclass. Not sure if it's too complicated and can be done simpler, like what @justvanrossum did with rename the snippet.

Edit:
The last version of fontgadgets is inside the RoboFontGadgets extension.

[typoman]

Here is the direct link to the subsetter module:
https://github.com/typoman/RoboFontGadgets/blob/main/fontgadgets.roboFontExt/lib/fontGadgets/extensions/features/subset.py

[justvanrossum]

Have you compared your subsetter with the one in ufomerge?

[typoman]

I haven't, but from the code, ufomerge seems very elaborate. I will try it to see how it works on the fonts I do the production on.