[XeTeX] Use of Unicode fonts in LaTeX

[Bruno Voisin]

Hi Ross,

Many thanks for your very quick response.

> utf8accents.sty  already does this;

Of course you're right! I can't imagine how I forgot to include it in 
the document I was writing, generally I include it in all my XeLaTeX 
documents. (Actually I know: I wrote that document with a partially 
non-functional brain, after a sleepless night fighting to meet a 
deadline...)

> However...
>
>  ... the Ux02DC code-point for  \textasciitilde  may be wrong.
> It's correct for the tilde-accent character, but you seem to
> want a non-accent tilde.
>
> You can get this with:
>
> \DeclareUTFcharacter[\UTFencname]{x007E}{\textasciitilde}% see x02DC
>
> Similarly for the other characters:
>   ...circum  ...grave  ...acute  ...macron  ...cedilla
>
> Should the  \textascii...  macros for these be in the  Ux00..  range ?
> Or should they be the accent characters in the  Ux02..  range ?

I think in this case there's a conflict between two incompatible 
approaches:

- The Unicode approach, in which the two tildes, namely the accent one 
and the non-accent one, are distinct characters, with distinct code 
points.

- The LaTeX approach (actually inherited from plain TeX), in which a 
tilde is an accent in a text font and a non-accent in a typewriter 
font. In this case, you're supposed to write \verb+~+ to get a 
non-accent tilde. Problem is, you get this character from another font 
(CMTT) instead of the current Unicode font.

I'm not sure what should be done here. I tend to think \textasciitilde, 
\textasciicircum and the likes (all the control sequences referenced in 
section 3.14 of usrguide.dvi) are commands with no argument, and hence 
are meant to be used as individual characters, not accents. Thus I 
would favour the UxOO range over the Ux02 one. But I'm no specialist.

I think this once again shows how useful would be the release of a 
LaTeX 3 turned towards the future, that is built upon Unicode and 
building bridges with XML, HTML, MathML and the like. But I'm getting 
pessimistic concerning whether LaTeX 3 will ever be.

My 0.02 €.

Bruno