[XeTeX] XeTeX vertical text layout support (for Linux & win32 users)

[Jonathan Kew]

On 19 Jun 2006, at 2:49 pm, Jjgod Jiang wrote:

> Now you can understand what I wished for, if some fonts don't
> provide such feature (ex. HanWangMingMedium), or provide
> features we don't want to use (ex. AdobeSongStd-Light).We
> could have some ways to select or adjust such stuff like
> punctation position.
>
> My question is, in which level we should implement these
> adjusting feature? TeX level or TeX macro level? or we should
> fix the font (or make a second copy of the font) instead?

I think the "right" solution is to fix the font, or make a modified  
version of the font, but this is dependent on (a) having the  
expertise and tools to do so, and (b) font licensing, which may not  
permit it.

Failing this, it is not too hard to adjust punctuation positioning by  
making each punctuation character active, and setting it in a box  
with suitable kerns to shift it to the center of the square (or  
whatever positioning you want).

Recognizing pairs of fullwidth punctuation characters and setting  
them both within a single character's width is a little harder --  
well, ok, it's quite a lot harder! -- but still possible to do at the  
TeX macro level. Again, an implementation within the font (using  
contextual selection of alternate glyphs, contextual positioning  
adjustments, or ligatures of two punctuation characters) would be  
preferable, IMO -- and would be available to other OpenType-based  
applications, too. (That's one of the aims of xetex -- to share this  
kind of typographic control with the rest of the world, rather than  
living in a separate world of fonts and font behaviors.)

JK