On Thu, Apr 04, 2013 at 11:13:46AM +0900, Dohyun Kim wrote: > 2013/4/4 Khaled Hosny <[email protected]>: > > On Thu, Apr 04, 2013 at 07:34:23AM +0900, Akira Kakuto wrote: > >> Hi Khaled, > >> > >> >One more question about vertical layout, the old XeTeX code was > >> >positioning vertical text somehow displaced on the baseline (compared to > >> >horizontal text), is this a desirable feature or a mere side effect? > >> > >> Attached is an example created by pTeX, which is > >> known to typset vertical text beautifully. > >> Please compare XeTeX's results, by mixing usual > >> horizontal text. > > > > Both old a new output don't seem quite right (one is displaced upwards > > and the other is displaced downwards) unless using the built in Latin of > > the CJK fonts (in fonts that rotate Latin glyphs in vertical layout), so > > I restored the old behaviour for sake of backward compatibility. Next > > year I hope to look into the text directionality as a whole and may be > > XeTeX will get real vertical layout. > > > > Wow! It works quite well now. Thanks a lot. > > I know from my experience that to compensate the baseline difference > between horizontal and vertical texts, moving vertical texts by 0.5ex > upwards is optimal. But I also honor your decision to keep backward > compatibility.
Ideally we should use BASE table to adjust base lines, but that needs a bit more work, so lets keep things like this for now. > Anyway, the only issue remaining is regarding the sign of x_offset. > To move right in real vertical mode is actually to move upwards in > xetex, so it seems that we have to reverse the plus sign of x_offset. > In fact I know a font that has vertical gpos feature using x_offset, > and this font works correctly when the following patch has been > applied. In the same logic, it seems that the sign of x_advance > should be reversed as well. But I am not sure as I do not have any > font to test this. Thanks, applied. I’ll keep x_advance until we have fonts to test. Regards, Khaled -------------------------------------------------- Subscriptions, Archive, and List information, etc.: http://tug.org/mailman/listinfo/xetex
