Some of the fonts we are working on have no OpenType features specified, and yet a “stub” GSUB table with zero features and zero scripts is being generated. I had thought that perhaps it was because there were glyphs present which we might expect to be susbsituted, such as ‘.sc’ or other variant glyph shapes/names. Well I have at least one font with none of that, and still Glyphs is generating an invalid GSUB of 10 bytes.
That is a makeOTF problem. I don’t touch the GSUB table at all. If you remove all kerning and mark feature you get an empty GPOS (10 byte) and no GSUB. You can test by running the
generateFont.command. It only runs
makeOTF with the data in that folder and no further post processing (it will place the product in the specified export folder and not in the Temp folder.
It would be nice if Glyphs removed the empty GSUB since it should know it wasn’t needed in the first place.
I believe that is something that would need to be addressed in makeotf directly. Not sure current makeotf still does that.