Re: TextAlign002 and use of textAlign on span elements

Thanks Glen,
I wasn't seeking to introduce new reqs. :-) 
If a p element does not necessarily incur crlf behaviour then what I need could presumably be achieved using two p elements in par with different alignment style attributes 'drawing' into the same region?

Regards
John
Sent by Blackberry

John Birch | Screen Subtitling Systems Ltd | Strategic Partnerships Manager
Main Line : +44 (0)1473 831700 | Ext : 270 | Office :  
Mobile: +44 (0)7919 558380 | Fax: +44 (0)1473 830078
john.birch@screen.subtitling.com | www.screen.subtitling.com
The Old Rectory, Claydon Curch Lane, Claydon,Ipswich,IP6 0EQ,United Kingdom


See us at Broadcast Video Expo – February 17th – 19th 2009, Earls Court 2, London, Stand number K56


Before Printing, think about the environment

----- Original Message -----
From: Glenn A. Adams <gadams@xfsi.com>
To: John Birch; Philippe Le Hegaret <plh@w3.org>; Public TTWG List <public-tt@w3.org>
Sent: Thu Dec 11 04:08:51 2008
Subject: Re: TextAlign002 and use of textAlign on span elements


Inline below.

On 12/11/08 7:05 AM, "John Birch" <john.birch@screen.subtitling.com> wrote:



 One aspect of broadcast subtitling requirements is multiple text alignments within a single displayed line... I.e left and right aligned text on the same 'displayed' line... While I realise this can be achieved using multiple overlapping regions with different alignment styles that's not an ideal solution...
 
 

This behavior doesn’t really work with the inline packing formatting model which is used by DFXP (as based on XSL). The box model of CSS also does not support this. So it is very unlikely we will do so in DFXP. This would also be a new requirement, which we are really not entertaining at this time, particularly since  there is already a solution in DFXP to support this indirectly (as you note). I think you should avoid modeling such behavior on the basis of the notion of having a single line.

What you are calling a single line is actually much more complex. In XSL it could be expressd as a table row with multiple cells (without borders) with each cell having different text alignments on their internal block content, something like:

<fo:block>
  <fo:table border=”none”>
    <fo:table-body border=”none”>
      <fo:table-row border=”none”>
        <fo:table-cell inline-progression-dimension=”50%” border=”none”>
          <fo:block text-align=”left”>
            <fo:inline>LEFT ALIGNED</fo:inline>
          </fo:block>
        </fo:table-cell>
       <fo:table-cell inline-progression-dimension=”50%” border=”none”>
          <fo:block text-align=”right”>
            <fo:inline>RIGHT ALIGNED</fo:inline>
          </fo:block>
        </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
  </fo:table>
</fo:block>

Of course, DFXP does not support tables, and it would add considerable complexity to do so now.


 
 Does a p element imply a crlf?
 


If you are asking whether an empty <p/> element would cause the insertion of an empty block (line) area, then the answer is no. This is not implied by DFXP’s presentation processing semantics. However, you could achieve this by using any of the following examples (and others):

(1) <p><br/></p>
(2) <p xml:space=”preserve”>&#x000A;</p>
(3) <p xml:space=”preserve”>&#x0020;</p>

All of these result in the generation of a single block (line) area which height is determined by applicable font* and lineHeight properties. The first of these three examples would be preferable.

Glenn





This message may contain confidential and/or privileged information. If you are not the intended recipient you must not use, copy, disclose or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation. Screen Subtitling Systems Ltd. Registered in England No. 2596832. Registered Office: The Old Rectory, Claydon Church Lane, Claydon, Ipswich, Suffolk, IP6 0EQ