[mpeg-OTspec] Vertical ligatures

[suzuki toshiya]

Excuse me,

John Daggett wrote:
>> I'd be interested in a realistic case where 'liga' is problematic in
>> vertical setting. John D's example is unrealistic, because
>> proportional Latin is rotated (not stacked) and monospaced Latin
>> wouldn't be ligated.

> Samples of book spines from a Tokyo bookstore:
> http://people.mozilla.org/~jdaggett/images/bookspineexamples.jpg
> 
> AERA article on the iPad:
> http://people.mozilla.org/~jdaggett/images/ex7-aera20100607-p26-ipad.png
> 
> Note the title of the Ryu Murakami novel "69" or the use of "Wi-Fi" in
> the iPad article, if the book was named "59" instead and the term
> "Wifi" used, both these examples with a standard OpenType Japanese
> font (e.g. Hiragino or Kozuka families) would exhibit the problem, the
> 'fi' ligature would appear since the 'liga' feature is on by default.
> So this *isn't* pure theoretics.

David Lemon distinguished the ligature in proportional Latin and monospaced Latin.
In John Daggett's pictures, all of the vertically stacked Latin are recognized
to be proportional? or monospaced?

In my personal recognization, vertically stacked Latin text in vertical Japanese
text is something like a mutation in forcibly import of Latin text, and the detailed
typographic features, the applicability to broader character sets are not considered
(I don't know if there is some common sense how to layout U+01C4 - U+01CC,
U+02A3 - U+02AD in vertically stacked Latin in Japanese text)

Regards,
mpsuzuki