FontLab>Glyphs duplicate kern bug

[RianHughes]

Something to look out for:

Exporting from FontLab using “Export to Glyphs” can produce a new “kern” feature in the “features” section.

This is read as a double-kern in apps when the .otf is exported.

Deleting this new feature, rebuilding the features, then exporting again fixes the issue.

Screengrabs for clarity:

Overkern (x2 value) for the ‘T.’ kern in Illustrator is -154:

Actual value in Glyphs is -77:

I deleted this feature that had been added in the FontLab>Glyphs export:

Rebuilt features, re-exported, rebooted Illustrator, and it is now fixed:

[SCarewe (Sebastian Carewe)]

Then this doesn’t sound like a Glyphs issue, but a FontLab issue, or am I misunderstanding?

[GeorgSeifert]

You mean our old script for fontlab or the .glyph file export from newer FL versions?

[RianHughes]

Hi Georg – the Glyphs file exported from the most recent FontLab using their “Export to Glyphs” option. (I’m using Glyphs 3.5, though I’m not sure that has a bearing.)

[GeorgSeifert]

Is there a kern feature in the file in FL? If so, that would be redundant but I think FL has a way to deal with this (skipping either the kern data or the feature).

So when you export the data into a glyphs file, it copies both, the kern data and the feature and glyphs will use both when exporting. You should be able to remove the kern feature in Glyphs.

[RianHughes]

Thanks, Georg – yes, that’s what worked for me. I deleted the feature, and the kerning is still there but not doubled. Unfortunately now I have to go back and check a whole bunch of fonts…