[XeTeX] Version 0.83 posted

[Bruno Voisin]

Le 17 juin 04, à 18:10, Jonathan Kew a écrit :

> XeTeX release 0.83 has been posted in Apple Installer and i-Package 
> formats; see
>
> [...]
>
> This release corrects the handling of \predisplaysize when using 
> AAT/OT fonts. It also adds an error message if you try to \dump a 
> format with preloaded AAT/OT fonts, as this is not supported.

Thanks, everything works now as expected.

I finished writing the document with which I had experienced the 
\predisplaysize problem. It was written in an AAT font (Trebuchet MS) 
for rm/bf/it, with Lucida Bright/NewMath for all other faces and 
styles. Getting such combination to work for math formulae as well as 
text was sort of a challenge. Not for the faint of heart!

An example of the oddities one has to cope with: due to the 
idiosyncratic encodings of the original TeX fonts, mathematical accents 
are taken from the roman text font, aka \rm or \textfont0; in my case, 
Trebuchet MS. However, because AAT fonts of course were not designed 
with such devious scheme in mind, they do not include math accents. 
Thus, what one has to do just to be able to use \tilde and \hat in 
maths while still keeping Trebuchet MS for roman text is:

- Define a new \macfam (math accents) font family just for holding 
these accents.

- Run testfont.tex on the corresponding font (in my case, lbr) to find 
out where the accents are.

- Redefine \tilde \hat etc. accordingly.

In practice, here are the instructions that were needed:

	\font\tenmac=lbr at 9.5pt   \skewchar\tenmac=127
	\font\sevenmac=lbr at 6.9pt \skewchar\sevenmac=127
	\font\fivemac=lbr at 5.2pt  \skewchar\fivemac=127

	\newfam\macfam
	\textfont\macfam=\tenmac \scriptfont\macfam=\sevenmac
	  \scriptscriptfont\macfam=\fivemac

	\def\hexnumber#1{\ifcase #10\or 1\or 2\or 3\or 4\or 5\or 6\or 7\or
	  8\or 9\or A\or B\or C\or D\or E\or F\fi}
	\edef\themacfam{\hexnumber\macfam}

	\def\hat{\mathaccent"7\themacfam AA }
	\def\tilde{\mathaccent"7\themacfam AB }

There were a number of similar adaptations to make. And this is only in 
plain TeX. I attempted for some time to achieve the same in LaTeX (as I 
would have liked to use the sophisticated math alignments allowed by 
the amsmath package), but finally gave up. It's probably manageable, 
but to the expense of such complexity that I wonder whether it's worth 
the effort (unless, of course, you are a LaTeX specialist and can 
achieve this in no time). And in any case, it would only be a least 
worse solution: the only satisfactory solution would probably be a 
fully Unicode TeX format.

Bruno Voisin