Variable Font in Flab VI Problems

Fernando Díaz

Hi,

I've finished creating my first variable font, very simple just 1 weight axis with several instances.

But I'm having some issues:
– When I export the font I get "WARNING:fontTools.varLib:Masters have incompatible prep tables, hinting is discarded"
– Don't understand how naming works.

Any other reading material or help would be appreciated!
Thank you.
F.

Adam Twardoch

1. In Font Info > Masters, the first column has empty circles, and one of them is a filled blue circle. That's your main master. Click there to declare another master the main master. 

2. Choose the same master in the lower-left of Font Info to switch to it. Go to the Names page. 

3. There, you define the Family name, the Weight, Width and Slope class (which will be used by apps that don’t understand that your font is variable, i.e. they’ll treat it as if it’s a one-master font with the main master only — that’s how TTF variable fonts work, they’re backwards-compatible). Normally, pick Regular as Weight there. Click the Auto button next to Style (should result in "Regular"), and click Build Names. 

4. Now go to the Instances page. There, for a variable font, you only need to define the Style name for each predefined instance. 

That’s it — in old apps, the variable font will use the main master’s Family name, and the Style name of the main master. Variable-aware apps will in addition present the predefined instances as styles. It’s best to include one instance at the same variation location as the main master, with the same style name as the main master. 

There are no fool-proof autohinting tools for variable fonts, so right now, when you get this warning, it means that your varfont will be unhinted. It’ll still work fine. 

There is a variable-aware version of ttfautohint in development. If you use macOS: 

1. Download https://github.com/twardoch/fontsurgery-tools/raw/master/macOS-devel/packaged/vfautohint.zip

2. Unzip, then inside the folder, double-click vfautohint.command

3. When Terminal opens, you can drag-drop your unhinted variable TTF into the Finder window and press Enter. You’ll get an autohinted variable TTF in the same folder. 

Fernando Díaz

This is Awesome, thank you Adam.

We are migrating from old FL5 to FLVI, it still has some issues, but overall I really like working with the progam (and I can't believe how easy is to make VF with it).

Congrats!

Jeremy Dooley

Adam, here's a request along these lines: https://forum.fontlab.com/fontlab-vi/request-import-instance-configuration/

Thomas Phinney

Regarding VF-autohint, Adam... how long should I let it run for before I assume it is just failing?

This would be on a VF with 18 masters, 3 axes, and (currently) 550 glyphs.

Thomas Phinney

(Killed after ~ 10 hours. Font was current build of Science Gothic from https://github.com/tphinney/science-gothic/blob/master/fonts/variable/UFO FontMake/ScienceGothicVF-no-italic.ttf

John Hudson

We've been using VTT for variable font hinting. It's a bit more work than a straight autohint: after running the VTT autohinter on the default instance glyphs you need to manually enter corresponding CVT values for the axis extreme instances, and may need to delete some unwanted instructions. But it gives good results that are editable.

Michael Rafailyk

@Adam Twardoch
I got the same result on vfautohint as a Thomas. The process is going about 5 hours and I terminate it. Perhaps the application need to tell the customer about some intermediate steps, or show an errors if appropriate.

Michael Rafailyk

@Adam Twardoch
Just checked vfautohint on single-axis variable font and it works fine. One second process.
But variable fonts with 3 axes hang the script and nothing happens.