Wrong glyph for U+0315 COMBINING COMMA ABOVE RIGHT

[dscorbett]

U+0315 COMBINING COMMA ABOVE RIGHT should be positioned above and to the right of its base, but in these fonts, it is rendered directly above its base. Its shape should be like U+0313 COMBINING COMMA ABOVE’s, but in these fonts, they look different. Here is ⟨k̕k̓⟩:

[tiroj]

Hmm. Many fonts use this character as the component glyph for the Czech and Slovak ‘caron’, hence the shape and position, and I've not heard complaint over this practice before. What is the source for the specification you cite?

[Regarding positioning, this character is not treated as a mark in the font, so positioning other than in the Czech/Slovak diacritics is a default offset.]

[dscorbett]

Czech and Slovak may contextually use this glyph for U+030C, but they don’t use the character U+0315, so they aren’t relevant to this issue.

I know of only two uses of U+0315: in Kwak̕wala after the first letter of a digraph, analogous to the use of U+0313 COMBINING COMMA ABOVE on a single letter; and in DIN SPEC 91379 and a related standard. For Kwak̕wala, at least, I would expect U+0315 to have the same shape as U+0313, since they both represent the same thing, just in different contexts. Is there any particular evidence that the comma above right should not be consistent with other comma-shaped diacritics? Because that seems like the most reasonable default assumption.

[tiroj]

I was under the impression that U+0315 had originally been encoded because it existed as a character in pre-Unicode Czech and Slovak character sets derived from typewriter keyboard layouts.

Kwakʼwala encoding is diverse. I have seen U+02BC, U+0313, U+0315, and U+0027, sometimes in the same document. For instance, the Facebook page of the U'mista Cultural Society includes Kwak̓wala and Kwak̕wala in the same paragraph.

I can make this change, but given the target language use of the STIX fonts, I suspect it won't be a priority fix for 2.10 but might be added to the list for 2.20 changes.

[moyogo]

U+0315 is used in a few romanisations like DIN 32706 for Armenian and DIN 32707 for Georgian. DIN 32707 also uses U+02BC separately so it’s not clear how they are meant to be easily distinguishable. Armenian	Georgian	Romanisation
ց	ც	c̕ 0063+0315
չ	ჩ	č̕ 010D (0063+30C)+0315
ք	ქ	k̕ 006B+0315
փ	ფ	p̕ 0070+0315
N/A	ჴ	q̕ 0071+0315
թ	თ	t̕ 0074+0315
N/A	ჸ	ʼ 02BC

These are used in German library catalogues. See for example Հայոց ցեղասպանություն - 100 / Hayoc̕ c̕eġaspanowt̕yown - 100 or "საქმენი იოვანე ზედაზადნელისანი" და "მარტჳლობაჲ" / "Sak̕meni Iovane Zedazadnelisani" da "Martwlobay".

[tiroj]

Hmm. I'm still left wondering how this should be positioned/spaced with regard to letters with right-side ascenders, when followed by left-side ascenders, when followed by superscripts, and all the other complications of things that break the typical combining mark positioning model.