GSUB lookup don't work when I generate my font!

[AlirezaAlipour]

I need single substitution in order to designing an cursive English script, every thing work when I test my font in the Metric windows, but when I generate my font, single substitution feature don't work in word processing or in web browser using CSS font-face.

In order to make this problem clear I designed a font that I attached to this issue. It has only four glyph and base on the init and the fina feature that I specified in GSUB it must substitute initial zero(0) and final one(1) glyph with a glyph that is consist of reference of same glyph addition to a line under that glyph. Unfortunately mentioned feature don't work in the generated font.
Problem_Example.zip

My environment is as follow:

• Fontforge Version: 11:21 UTC 24-Se-2017

• OS: Ubuntu 18.10, I also I had same problem in Ubuntu 16.04

• Word Processing Application: LibreOffice Writer

[frank-trampe]

@AlirezaAlipour, this isn't quite specific enough to be handled as an issue. We would need to know specific deficiencies in the generated TrueType file. Please post to the FontForge user list with your input (SFD) file and output (TTF) file and ask for help finding the specific reason that Word isn't rendering the way you expect.

[AlirezaAlipour]

Thank @frank-trampe very much for your assist :)

I wish you a happy new year :)

[AlirezaAlipour]

I'm waiting for a solution :)

[dscorbett]

This isn’t a problem with FontForge. 'init' and 'fina' are for scripts like Arabic: they don’t work for Latin. You’ll need to use a contextual substitution to determine whether a glyph is in initial or final position.

[AlirezaAlipour]

Thank David very much :)

Unfortunately I forgot to update and close this issue, I researched on the web and asking from a kind man by email then I figured out that I can use contextual substitution or contextual chaining substitution_ now I'm using contextual chaining substitution for my propose_ and as you described, 'init' and 'fina' features are don't applicable for Latin and these features are used for Arabic.

I'm thankful to every one that help me :)