IMO, the correct answer is 2, except that “all common fonts” is more sweeping
that necessary: it’s sufficient to have fonts used for fallback in platforms
and browsers, and the related fallback logic, to get updated. Of course, that
takes some time, and it’s not even two months since Unicode 11 was released.
The Georgian community understood that it would take time to get
implementations in place, and that they would need to take measures to smooth
over that transition — which can include having Web sites for Georgian
businesses and institutions using fonts to match the requirements of the
content.
Peter
From: Unicore <unicore-boun...@unicode.org> On Behalf Of Markus Scherer via
Unicore
Sent: Wednesday, July 18, 2018 3:05 PM
To: unicore UnicoRe Discussion <unic...@unicode.org>
Cc: mark <m...@macchiato.com>
Subject: Unicode 11 Georgian uppercase vs. fonts
Dear fellow Unicoders,
We’ve run into some significant problems with the Georgian capital letters
added in Unicode 11. If you have run into them yourselves, or have feedback on
our brainstormed solutions below, we’d love to hear your thoughts.
Here's the problem. The vast majority of Georgian fonts do not yet have the new
uppercase characters. So when any system uses case mapping to uppercase text
(e.g. browsers interpreting CSS’s text-transform: capitalize), then the users
of Georgian will see boxes (“tofu”) if the font they are using does not have
the glyphs.
For example, a program constructs a web page with buttons. It uses a CSS style
to uppercase text in buttons, as a house style. Unless the user has a very
up-to-date font, they see tofu (boxes). If a server does backend rendering, its
font has to be very up-to-date. We also saw this problem in a program that was
doing titlecasing, but on the first character it used the uppercase mappings
rather than titlecase mappings. Not the right thing to do, of course, but code
that accidentally works (most of the time) doesn't get fixed if nobody reports
a bug about it.
All of these will result in bad bugs in the UI, in software that formerly
worked fine.
We brainstormed some options to fix this:
1. Get all call sites to change their code to not uppercase Georgian (and
fix titlecasing to use the titlecase mappings, not the uppercase mappings).
Since we have no control over call sites and release cycles of affected
software, this would not help Georgian users for a long time, if ever. We’d
eventually want to retract these changes, creating even more work.
2. Change all common fonts with Georgian characters to add the U11.0 ones.
This should eventually happen but would probably take a couple of years at
least, which does not help users in the short term.
3. Hack font CMAPs to just map the new characters to the glyphs of the old
ones. Works but only when a programmer can control the fonts used, such as with
server-side rendering or downloadable fonts.
4. Remove the uppercase mappings for Georgian, until the fonts catch up.
* Would at least have to be done in all browsers, otherwise web apps
will still break for Georgian.
* A broader alternative is to do it in ICU. Because that is used by the
majority of the browser implementations, it would solve the short-term problem
for the browsers — and many other programs. Drawback: Non-conformant, and
uppercasing will be inconsistent depending on who has which variant of ICU
(with vs. without hack, on top of: with Unicode 11 vs. before Unicode 11).
* One precedent is that in CLDR we deliberately hold back from using
new currency characters until the font support is sufficiently widespread.
(Wishing we'd held back the uppercase mappings in Unicode 11.0 too!)
Mark & Markus
