CJK vertical text
rpresser
webSupergoo's abcpdf, but I think I have a more basic question first.
The project will need to be able to insert CJK text in several
orientations. The two that I have support for from abcpdf are "English
book" type (left-to-right lines which advance top-to-bottom), aka ltr-
ttb, and "Chinese newspaper" type (top-to-bottom lines which advance
right-to-left), aka ttb-rtl. The product embeds fonts for the former
with the encoding Identity-H and fonts for the latter with the
encoding Identity-V. If the same font is used in both directionalities
it has to be embedded twice. All well and good.
Trouble is, one customer is convinced that on the Chinese mainland, it
is common to have "Mongolian script" type (top-to-bottom lines which
advance left-to-right), aka ttb-ltr. I haven't been able to find any
examples of this on the web, even photographed print. The Unicode
standard 4.0 still says that Monglolian script is the only language
system in the world that uses that text directionality. The only other
reference I have found to such a directionality on the web is an
invented language called "Hanadute". http://archives.conlang.info/vhau/qingia/keirpaerchian.html
Omniglot.com lists some other ttb-ltr writing systems but they are all
related to Mongolian.
Question 1: Is it true that Chinese is sometimes written ttb-ltr?
Question 2: Does the PDF standard even allow fonts to be embedded to
do this? Or am I going to have to play tricks with setting individual
lines?
ken
d7e05f...@n1g2000vba.googlegroups.com>, rpre...@gmail.com says...
> Question 1: Is it true that Chinese is sometimes written ttb-ltr?
I've never heard of it but it doesn't mean its not true.
> Question 2: Does the PDF standard even allow fonts to be embedded to
> do this? Or am I going to have to play tricks with setting individual
> lines?
PDF doesn't care how glyphs are aligned. It has no concept of reading
order at all. Glyphs are placed on the page, and the currentpoint
advanced by a given amount (which may be negative). The direction of
advancement is given by the writing mode (WMode) either horizontally or
vertically.
Even if that were not the case, you could position each glyph
individually.
Ken
Peter Flynn
[...]
> Question 1: Is it true that Chinese is sometimes written ttb-ltr?
> Question 2: Does the PDF standard even allow fonts to be embedded to
> do this? Or am I going to have to play tricks with setting individual
> lines?
You might want to discuss this with an implementer, such as the author
of the montex package:
http://www.ctan.org/tex-archive/help/Catalogue/entries/montex.html
///Peter
Gernot Hassenpflug
> In article <eaa49783-0466-4012-b822-
> d7e05f...@n1g2000vba.googlegroups.com>, rpre...@gmail.com says...
>
>> Question 1: Is it true that Chinese is sometimes written ttb-ltr?
>
> I've never heard of it but it doesn't mean its not true.
Certainly, most academic and business books are. Same in Japan: while
novels and paperbacks are mostly rtl-ttb, the academic and business
books all follow the Western ltr-ttb pattern. Of course, typographic
rules are quite different.
Regards,
Gernot
Ross Presser
> ken <k...@spamcop.net> writes:
> > In article <eaa49783-0466-4012-b822-
>
> >> Question 1: Is it true that Chinese is sometimes written ttb-ltr?
>
> > I've never heard of it but it doesn't mean its not true.
>
> Certainly, most academic and business books are. Same in Japan: while
> novels and paperbacks are mostly rtl-ttb, the academic and business
> books all follow the Western ltr-ttb pattern. Of course, typographic
> rules are quite different.
I am making a distinction between ltr-ttb and ttb-ltr that you seem to
have missed.
ltr-ttb is like English text: characters within each line of text
progress from left to right, and successive lines of text progress
from top to bottom.
ttb-ltr is how Mongolian script is written. Characters within each
line of text progress from top to bottom, and successive lines of text
progress from left to right. There is evidence that Mongolian script
evolved by turning Semitic rtl-ttb methods 90 degrees
counterclockwise, resulting in ttb-ltr.
In any case, as ken said, the PDF format has no concept of reading
order at all.
Gernot Hassenpflug
> I am making a distinction between ltr-ttb and ttb-ltr that you seem to
> have missed.
Indeed.
> ltr-ttb is like English text: characters within each line of text
> progress from left to right, and successive lines of text progress
> from top to bottom.
>
> ttb-ltr is how Mongolian script is written. Characters within each
> line of text progress from top to bottom, and successive lines of text
> progress from left to right. There is evidence that Mongolian script
> evolved by turning Semitic rtl-ttb methods 90 degrees
> counterclockwise, resulting in ttb-ltr.
Thanks for explaining that!