Vafa,
I almost know nothing about vertical typesetting but can not you do vertical typesetting by some rotation?
Yes and no. For the normal syllabic scripts and chinese characters, you can. However, there are also half-height OR half-width characters, depending on the writing direction. In horizontal writing, しゃく has a half-height や, but in vertical writing, it would be し on top, then a half-width や, and then a く. Punctuation is radically different too. For instance, これは日本語です。 ends with the symbol [。], which is essentially a circle in a quad's lower-left quadrant. For vertical writing, this is instead [︒], with the circle in the upper-right quadrant. Quotation, too, is different, with 「これ」 being horizontal style, but vertically being written as ﹁, then こ, then れ, then ﹂. These are not just "rotated" but having different glyph metrics in vertical form.
In fact, almost all (proper) CJK fonts rely heavily on the vert/vrt2 features to indicate glyph substitution in vertical mode, and has been a bit of a bother up until basically today still =)
(hopefully fontspec 2, once all open issues are resolved, will have solved that =)
- Mike "Pomax" Kamermans nihongoresources.com -------------------------------------------------- Subscriptions, Archive, and List information, etc.: http://tug.org/mailman/listinfo/xetex
