W3C home > Mailing lists > Public > www-style@w3.org > February 2017

Re: [css-fonts] font-language-override property and descriptor

From: fantasai <fantasai.lists@inkedblade.net>
Date: Mon, 20 Feb 2017 22:21:58 -0500
To: John Hudson <john@tiro.ca>, Jonathan Kew <jfkthame@gmail.com>, www-style@w3.org
Message-ID: <da1463d9-8aac-c1b9-e005-d8b8c9d8ae17@inkedblade.net>
On 02/03/2017 07:52 PM, John Hudson wrote:
> On 03/02/17 16:07, fantasai wrote:
>> I'd like to check with John Daggett on this point... in the meantime,
>> what's the use case for having one font use one language value and a
>> different font use a different one--is that ever a thing that happens?
>
> The first use case is OpenType fonts with different Language System coverage, one of which might be suitable for the document
> language without that language being included in the font Language System coverage. My usual example for this is a document in
> Macedonian being displayed using a font that contains an SRB (Serbian) Language System but not an MKD (Macedonian) Language
> System. This is not unusual, as font developers at the time such a font is made might only have reliable information about
> specific language typographic norms, e.g. Serbian, and not be aware that the same norms are suitable for Macedonian.
>
> The second use case arises from the fact that an OpenType Language System tag is not, in fact, a natural language tag directly
> analogous to a document language tag. An OT Language System tag in combination with an OT Script tag, indicates a particular
> typographic form of a writing system. In some cases, this can be mapped directly to a document language tag, in some cases it
> might be better mapped to a locale, and some registered Language System tags indicate notation systems that are not specific
> to any individual language. So, the two phonetic notation system tags for IPA and Americanist transcription — IPPH and APPH,
> respectively — will be essential for enabling appropriate phonetic forms of some Greek letters that in a font may differ from
> the default Greek alphabet style. This is only possible if authors are able to directly specify the appropriate OT Language
> System tags independently of document language tagging.
>
> There is third use case, but it is very peculiar, and I don't think I've actually seen a font built in this way: it is
> possible that a combination of OT Script and Language System tags can be used to identify a typographic convention for a
> script that is particular to a locale. So, for example, if one examines German and French editions of classical Greek texts of
> the 19th Century, one observes fairly regular and differing conventions regarding use of the long and short forms of the
> letter beta (I forget the exact conventions; I recall that one uses the long form only at the beginning of a word). These
> conventions could be captured in an OT font, using contextual substitutions under particular Language System tags, in such a
> way that text in Greek characters (<grek> Script tag) could be processed according to either FRA (French) or DEU (German)
> Language System. In that case, the Language System tag isn't indicating the document language — Greek — at all, but rather a
> convention for Greek typography associated with French or German publishing conventions.

I think only the first one is actually an answer to my question,
but the other scenarios are interesting to have documented here
in any case. :)

~fantasai
Received on Tuesday, 21 February 2017 19:39:58 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 21 February 2017 19:39:59 UTC