GPOS kern table not used in Scribus (kerning pairs for Latin+diacritics)

[Michal Hlavaty]

All Ubuntu fonts have missing some kerning pairs of letters with diacritics. Capital "T", "V" and "P" together with "o", "e" and "a" have different distances between letters with and without diacritics. It seems that some of the letters have no preconfigured kerning.

Please see attached PDF file.

[Shiraaz Gabru (shiraaz)]

Can you tell us what application this PDF was originally created on please.

It may be that this application does not use 'GPOS' kern table information for kerning glyphs, but uses the more simplified 'kern' font table. Only the GPOS kern tables will hold the full kerning information for the font, including the accented glyphs. A non-GPOS table (called 'kern') holds a limited amount of kerning information for applications that do not access the GPOS kern information. This table however is limited in its format and maximum size so cannot hold kerning information for all the glyphs in the font.

[Michal Hlavaty (hlavaty-michal)]

Document was created in Scribus 1.3.8.

[Paul Sladen (sladen)]

The metadata shows "Scribus 1.3.8/Scribus PDF Library 1.3.8".

[Paul Sladen (sladen)]

Michal: can you attach the Scribus source file to enable easier testing?

[Michal Hlavaty (hlavaty-michal)]

I send .sla file.

For this test was used UbuntuBeta font.

[Mark Shuttleworth (sabdfl)]

Hmm.. unfortunately that crashes scribus-trunk. I wanted to see if a PDF
created with the newer toolchain has the same problem.

Mark

[Shiraaz Gabru (shiraaz)]

Scribus doesn't support OT kerning: http://bugs.scribus.net/view.php?id=7910