[XeTeX] Problem changing default fonts

[Drébon]

On 26/09/2010 20:40, Will Robertson wrote:
> On 2010-09-27 02:14:03 +0930, Drébon <bedouin_drebon at hotmail.com> said:
>
>> \usepackage{pxfonts}
>> \usepackage{txfonts}
>> \usepackage[osf,sc]{mathpazo}
>
> You just changed the math/text font three times...
>
Oh... indeed...

So I guess in I should only have that kind of preamble :

\usepackage[osf,sc]{mathpazo}
\usepackage[euler-digits]{eulervm}    %for math text
\usepackage{helvet} %for sans serif text
>
> If you're only using UTF8 for Latin input text, you can use pdfLaTeX with
>
>    \usepackage[utf8]{inputenc}
>

Well, this was not the aim... Actually in my preamble I have macro 
definition that take place before anything... And that user may change 
so that it contains anykind of unicode character... By just using 
[utf8]{inputenc} latex processes those definition in iso-8859-1. So it 
forces me to have two encoding in the same document (of course not the 
same file).
> But if you insist on using XeLaTeX, you should probably go the whole 
> hog and load a Unicode font. Try TeX Gyre Pagella as a replacement for 
> mathpazo as your text font. Something like
>
> \setmainfont[
>  Extension=.otf,
>  UprightFont=*-regular,
>  ItalicFont=*-italic,
>  BoldFont=*-bold,
>  BoldItalicFont=*-bolditalic,
> ]{texgyrepagella}
>
If I am not wrong, this does only redefine the text font and not the 
math font isn't it ?


Thank you very much for your answer.

-- 
Best wishes, D.