Typophile

Class Kerning Discrepancy

Robby Woodard

I'm putting together an OpenType font with a lot of glyphs. Extended Latin, Small Caps, OS and Proportional Figures. I have the class kerning worked out to my satisfaction and my VFB file has 1,061 pairs.

After I generate the OTF and open that back up in FL, the kerning pairs have ballooned to 22,445. And I see that several of my kerning classes have disappeared.

Is this typical? I don't see anywhere in the options where I asked FL to expand or flatten the kerning.

What is happening to my carefully organized classes?

James Montalbano

...

twardoch

FontLab Studio 5.1 up to 5.1.2 build 4447 has a bug: it expands class kerning when opening an OpenType font. This problem has been fixed in build 4549:
http://forum.fontlab.com/fontlab-studio/fontlab-studio-5-1-2-pre-release...

However, build 4549 has other problems of its own, so I'd recommend KEEPING your current FontLab Studio version installed (as described in step 2 of the installation instructions in the article linked above). Then, install build 4549, run it, open the OTF, save as VFB, and then continue working in your previously installed build.

Captured from web.archive.org on 23 Aug 2013. view this capture