Unstable gradient export with fontmake after fontools/ufo2ft update -

Hello everyone, I’ve been experimenting with generating variable Colrv1 font files with fonttools for the last couple of weeks. The ultimate goal is to build a Colrv1 font with variable outlines as well as variable gradients - which I know not possible yet. So a goal for now is to build a Colrv1 font with gradients but variable outlines only.

With fonttools 4.33.3 and ufo2ft 2.27.0 i have been able to create working .ttfs with fontmake myfile.glyphs -o variable. I have been following this thread. I am new to GitHub issues/reporting, please redirect me in case this is the wrong way/place to post.

After the update to fonttools 4.34.0 and ufo2ft 2.28.0 I am not able to export variable and gradient displaying .ttfs. I use FontGoggles (1.4.1) and https://fontgauntlet.com to preview files (works for the correct export with fonttools 4.33.3 and ufo2ft 2.27.0) In some cases they are displayed in a broken way however the export of something visible in the .ttf is inconsistent – to my understanding. Variability is not displayed.

Glyphs file for testing: amb_var_2.glyphs.zip

Export with old version: Output File: AMBIG-VF1.ttf.zip

Export with new version: Output File (nothing visible) from attached .glyphs file: AMBIG-VF.ttf.zip

Output File (some gradients visible): AMBIG_PROP-VF.ttf.zip

Does somebody have an idea where the issue could be?

[lenaweber404]

Thank you for your reply! I’ll try that. With the new fontGoggles version I was able to display the gradients. My font has multiple Axis, one of them also including variable COLR. So far I haven’t been able to export variable outlines + variable gradient (multiple axis), but on their own (1 axis only) I was able to export variable Gradients for the first time just now! Thank you, very exiting!

[lenaweber404]

Btw, that’s a cool font 👍

Thank you 😃