[XeTeX] Default values of \pdfpage{width, height}

[Andreas Matthias]

Bruno Voisin wrote:

> Le 3 août 07 à 14:23, Andreas Matthias a écrit :
> 
>> Ross Moore wrote:
>> 
>>> But the \pdfpagewidth  and  \pdfpageheight
>>> are not parameters that are meant to be changed willy-nilly
>>> throughout a document.
>> 
>> There's nothing wrong with changing them the way you like:
>> willy-nilly or however.
>> 
>> I agree that in general it is not easy to do something sensible
>> with it because of TeXs asynchronous output mechanism. But
>> that doesn't mean that they are "not meant to be changed".
> 
> Just in order to get a "standard" to refer to, I've been checking the  
> way the papersize \special works in dvips. According to the intro of  
> section 4 of dvips.pdf:
> 
> "Since the intended paper size is a document design decision, not a  
> printing decision,
> such information should be given in the TEX file and not on the Dvips  
> command line. For
> this reason, Dvips supports a ‘papersize’ special. It is hoped that  
> this special will become
> standard over time for TEX previewers and other printer drivers."
> 
> Alas, dvips seems to really have been designed with printing in mind,  
> not PS/PDF file creation, so that the papersize \special is really  
> meant to specify paper size

Okay.

> and is not supposed to be changed throughout a document.

That's not from the manual.

> Says in particular section 4.1 a bit later:
> 
> "The papersize special must occur somewhere on the first page of the  
> document."

I didn't search the PS/PDF specifications but I am certain that
a PS/PDF document without paper size information (Mediabox, etc.)
is not a valid PS/PDF. That's why dvips and other drivers must
know the paper size. And that's especially true for the very fist
page, so that there must be some paper size information on this
very first page. But it doesn't say, that the paper size should not
be changed on the following pages.

Nowadays PDFs with varying paper sizes are quite common. And it is
possible to do that within a PS as well. It is definitely legal
to do that.


Ciao
Andreas