Re: per-buffer language environments

[Stephen J. Turnbull]

Werner LEMBERG writes:

 > IMHO, the Romanian functionality is nothing Emacs should take care at
 > all.  It should simply forward a `language environment' to the font
 > library which has to take care of using the proper glyph.  Today, most
 > of the good multilingual OpenType fonts have support for that
 > mechanism.

It's not obvious to me that that is a generally correct solution (see
below for why I don't think it appropriate for CJK), but if it does
work for European (and probably many other) languages, that's great.

BTW, did you mean to say good *free* multilingual OpenType fonts, and
just assume freedom, or was the omission prompted by reality?  Freedom
matters to Emacsen, of course.

 > However, for CJK stuff, the situation is very different.  Virtually
 > *no* font supports different glyphs for Chinese, Japanese, and
 > Korean.

It's not obvious to me that they should.  If you look at the multiple
Chinese languages, Japanese, Korean, and Vietnamese, you see that
there are clearly Chinese styles (and I suspect differences among
Taiwanese, Cantonese, and Mandarin styles), clearly Japanese styles,
etc. with respect to stroke endings, attitude of slanted strokes,
contact points, and extensions at join points.  I don't think that
people from different East Asian culture/languages would find
compromise fonts acceptable, except perhaps in the very simplest of
Gothic and Maru Gothic faces (Japanese names for font styles basically
equivalent to sans-serif upright faces for Latin characters).  Eg, in
Emacs, even as one who learned Japanese late in life, I've gotten used
to distinguishing Chinese spam from Japanese spam via such stylistic
differences (strictly speaking, it's unnecessary as the presence of
kana is normally decisive).  I have to wonder if such stylistic fine
points might not be very important to the comfort level of someone who
is bilingual in Chinese and Japanese.

But as a practical matter, today if Emacs wants to display Chinese
attractively (maybe even "correctly"), it cannot use a Japanese font
and compromise fonts with multilingual support basically don't exist.
So even if support in Emacs for choosing appropriate fonts based on
language is not needed for Romanian, it is needed for Han-based
languages.