Add language support for Vietnamese

[maddie-moe]

Hello,

When using diacritics in Google Docs or MS Office, the diacritics do not appear to be displayed properly, and some letters having diacritics become smaller in x-height. Diacritics render just fine in Adobe softwares. I'm not sure if there is anything that can be done with the font rendering, or if it is an issue with Google/Microsoft that is out of the font designer's control. Thank you kindly for your time and attention.

(Figtree Diacritics on Google Docs) (Figtree Diacritics on Adobe Illustrator)

[lazarljubenovic]

Are you sure that's even the same font? Even the letters without diacritics look completely different. Most obvious in the last two e's, I think.

[maddie-moe]

Oops, you are correct. Looks like Adobe Illustrator defaulted the line of text to Myriad Pro since these characters aren't supported. I'll amend the issue to instead add language support for Vietnamese. Thank you.

[erikdkennedy]

This will be a while (unless someone else is able to do a PR), but I will leave this issue open so others can comment, upvote, and harangue me 😁

[RandomMaerks]

I was really looking forward to adding Vietnamese characters, until I got hit with an error.

I only have FontForge as a font editor because I can't use Glyphs (i have windows), so I had to build UFOs using fontmake. But then, when I opened the .ufo with FontForge, it hit me with a "There were errors when parsing the feature file and the features have not been applied". Upon checking the GSUB lookup, nothing was there. I've tried with different font projects, building .ufos from .glyphs. They all give very different results, some worked and others didn't. And I should probably report this to the FontForge repo.

But I'm wondering if you could include the .ufo files for the fonts in the source folder or just send it to me somewhere? cuz I think building .ufo from .glyphs might be what's causing the issue