search

liberationfonts / liberation-fonts

The Liberation(tm) Fonts is a font family which aims at metric compatibility with Arial, Times New Roman, and Courier New.
Other
439 stars 21 forks source link

Inaccessible Greek glyphs #53

Open aswigon opened 2 years ago

aswigon commented 2 years ago

Describe the bug

The Liberation fonts contain correctly designed glyphs for Ancient Greek with vowel length marks (macrons and breves). There are no precomposed Unicode codepoints for most of these characters, but they are often used in dictionaries and textbooks. However, these glyphs (highlighted) seem to be inaccessible to users:

3

To Reproduce

Let's consider the glyph named uni03B1030403130301 (second in the highlighted sequence above). Neither the sequence encoded in its name:

$ hb-shape liberation-fonts-ttf-2.1.5/LiberationSerif-Regular.ttf --unicodes=03B1,0304,0313,0301
[uni1FB1=0+1073|uni0313=0+0|acutecomb=0+0]

nor the partly composed sequence used by Wiktionary e.g. here (not in the top-level headword; see the first inflection table):

$ hb-shape liberation-fonts-ttf-2.1.5/LiberationSerif-Regular.ttf --unicodes=1FB1,0313,0301     
[uni1FB1=0+1073|uni0313=0+0|acutecomb=0+0]

cause the glyph uni03B1030403130301 to be used. Visually, the placement of the acute accent is only slightly wrong, however the breathing mark (comma accent) is totally misplaced in all cases:

$ hb-view liberation-fonts-ttf-2.1.5/LiberationSerif-Regular.ttf --unicodes=1FB1,0301,1FB1,0313,1FB1,0313,0301 --output-file=1.png

1

Expected behavior

The Theano fonts display these stacked diacritics correctly:

$ hb-view TheanoModernRegular.ttf --unicodes=1FB1,0301,1FB1,0313,1FB1,0313,0301 --output-file=2.png

2

Desktop (please complete the following information):

Additional context

These base letters can have a macron or a breve: Αα Ιι Ϊϊ Υυ Ϋϋ. Possible diacritics to be stacked on top of the macron/breve are:

  1. U+0313 COMBINING COMMA ABOVE
  2. U+0314 COMBINING REVERSED COMMA ABOVE
  3. U+0300 COMBINING GRAVE ACCENT
  4. U+0301 COMBINING ACUTE ACCENT
  5. 1 & 3
  6. 1 & 4
  7. 2 & 3
  8. 2 & 4