Font Forum

Thanks. So at least if it something wrong with my fonts, I can fix it; not a bug in PagePlus X9 over which I have no control. The syntax check will help a lot to debug my fonts.

I need a rest before I can tackle this.

I was unable to get anywhere with this. I even tried deleting the kern feature and running the autokern wizard. That produced 395K kerning pairs, with a lot of junk pairs, but no kerning pairs for Small or Petite Capitals, nor for Caps paired with super/subscripts.

For each class based pair adjustment positioning subtable, you must ensure each glyph is added to (at most) one pair positioning first class and to (at most) one pair positioning second class.

You can visualize it as starting with a huge matrix with only single glyphs as both columns and rows. Then you start merging several columns, so they become a class. Then you do the same for the rows.

And of course for this to work, the right side-bearings of glyphs in a first class, must be very similar. Likewise for the left side-bearing for glyphs in second class.

I believe other font editors facilitate this process by glyph related options that allow you to specify the main or leading glyph to form such glyph classes for pair positioning.

Erwin Denissen wrote: ↑Thu Jun 11, 2020 10:37 pm For each class based pair adjustment positioning subtable, you must ensure each glyph is added to (at most) one pair positioning first class and to (at most) one pair positioning second class.

All this seems to be saying is repeating what I thought I already understood, that glyphs should not overlap, but I already did that.

Another bug is that pressing Cancel while syntax checking does not stop it. The dialog greys out only, but the syntax check continues until it is complete.

Bhikkhu Pesala wrote: ↑Sat Jun 13, 2020 8:55 am All this seems to be saying is repeating what I thought I already understood, that glyphs should not overlap, but I already did that.

Yes, the glyphs in the glyph classes must not overlap. If they do, you will see the accompanying compiler warning(s).

Bhikkhu Pesala wrote: ↑Sat Jun 13, 2020 8:55 am Another bug is that pressing Cancel while syntax checking does not stop it. The dialog greys out only, but the syntax check continues until it is complete.

This will be fixed with the next upcoming update.

After totally recoding the lookups, the compiler does not report any more errors, but the Petite Capitals and Caps/subscript pairs do not kern. The latter is unimportant, but I do need to Petite and Small Capitals to kern properly. My other fonts still seem to work OK.

Below, the lines in blue all kern as expected, those in crimson do not kern in PagePlus, though they do in FontCreator.

The font seems to be fine, and it works in Firefox. I suspect it is a PagePlus issue.

Balava works just fine. There is no pair for Vo subscript, but Av superscript is kerned, and Petite Capitals are kerned.

We can not test the fonts in Word, as it emulates small caps.

Maybe someone can test both fonts in Illustrator or in Affinity Designer?

Do attach both font files here, so it is easy for another person to test 'm.

It looks like an issue with mapping. The Petite Capitals in the older Balava font are mapped to the PUA while the Small Capitals are unmapped, and kerning fails for those glyph pairs.

Confirmed

If I add mappings to the Petite Capitals, all of the kerning pairs that use them now work in PagePlus. That is good news as I can now fix the problem in my fonts so that PagePlus can use them as they were designed.

Good to know you have found the cause. It still looks like a PagePlus bug to me.