[XeTeX] XeTeX vertical text layout support (for Linux & win32 users)
jonathan_kew at sil.org
Sat Jun 17 19:01:29 CEST 2006
On 17 Jun 2006, at 4:12 pm, Jjgod Jiang wrote:
> Hi all,
> Recently I've been trying to add vertical text layout support to
> XeTeX (and
> xdvipdfmx) Linux & win32 versions. ....
That's exciting.... it's been on my list of things to do, but I
haven't had time to work on it, so if you get it done first, I'll be
very happy. :)
I've looked over your description briefly, and it's a promising
start, but as far as I understand it, there will be more work needed
before it's ready to use, and provides equivalent functionality to
the "vertical" attribute used with ATSUI fonts on OS X (which would
be my goal).
It seems to me that your suggested changes so far will allow the
"vertical" attribute to be specified for OT fonts, and pass this to
xdvipdfmx via the font_def flags; but in addition, the actual layout
process in xetex needs to be aware of the vertical flag, and use the
vertical rather than horizontal glyph metrics.
(You might get acceptable results with typical "square" CJK glyphs,
but for the general case, I think the layout engine needs to be
modified to recognize the vertical option.)
In addition, I'm guessing that xdvipdfmx will have problems if you
use the same font in both vertical and horizontal modes, because
you're storing the layout direction in the fontmap (in the form of
the encoding name), but the fontmap entries are keyed just on the
font name -- so the same entry will be used regardless of the writing
If I have a little time, I'll experiment with some of this, and see
how it fits together in practice. Thanks for getting it started!
More information about the XeTeX