RE: from-page-master-region() and Re: reference-orientation

Peter,

At this time I have to apologize that a careful
response to the issues you raised is still not
available.  It's not that you don't deserve one,
but this is an area that is complex enough that
it takes time and expertise to provide one, and
those on the SG with the expertise have not had
the time.  However, we do not wish to hold up the
progress of XSL 1.1 further, hence this message
from me now.

The best I can say given my level of (lack of)
expertise in this area of XSL-FO is that the SG
did spend a lot of time discussing both inheritance
within the FO tree in general and your issues in
particular, and we came to the consensus that, while
each alternative has its pros and cons, the model that
we are choosing is reasonable and is the one we wish
to use at this time.  We have tentative plans to provide
additional capabilities at a later date for supporting
the requirements that our chosen model does not yet 
support, but those will not make it into XSL 1.1.

At this time, the XSL FO SG has made plans to request
the transition to CR for XSL 1.1.  That phase will 
entail almost three months of implementation testing
and feedback, and we will be taking comments from all
during that phase too.

However, at this time, given what (little) I am able
to say above, I have to ask that you reply to this email 
(cc-ing the xsl-editors list) saying whether you wish
for us to flag this issue as an official objection 
during our upcoming CR transition request.

If we do not hear either way by February 15th, we will
assume you do not require us to flag this issue as an 
official objection.

In either case, we continue to plan to produce a more
detailed response to your issues during the CR period.

Paul Grosso
for the XSL FO SG
(though my attempted explanation above is just my own)


> -----Original Message-----
> From: xsl-editors-request@w3.org 
> [mailto:xsl-editors-request@w3.org] On Behalf Of Peter B. West
> Sent: Tuesday, 2005 August 09 9:23
> To: xsl-editors
> Subject: Re: from-page-master-region() and Re: reference-orientation
> 
> 
> Peter B. West wrote:
> > Sharon,
> > 
> > My apologies for taking so long to respond.
> > 
> > I did appreciate that the use of the function did not 
> violate lexical
> > (is that an appropriate term?) inheritance.  My concern was with the
> > mooted changes to "6.4.5 fo:page-sequence", under "Trait 
> Derivation".
> > 
> >  'The reference-orientation and writing-mode of the
> >  region-viewport-areas are determined by the values of the
> >  "reference-orientation" and "writing-mode" properties of the
> >  fo:page-sequence.'
> > 
> > Is this change still in play?
> 
> Sharon,
> 
> The answer, as the Last Call makes clear, is "yes".  What a 
> astonishing
> performance by the editors.
> 
> This change purports to be a "clarification."  What it 
> clarifies is that
> in 1.0 (and the initial draft of 1.1), reference-orientation and
> writing-mode defined on elements of fo:simple-page-master 
> subtrees were
> completely inaccessible.  In neither 1.0 or the first draft of 1.1 do
> reference-orientation or writing-mode appear as properties applying to
> fo:page-sequence.  They do, however, appear as properties applying to
> fo:simple-page-master, fo:region-body, fo:region-before,
> fo:region-after, fo:region-start and fo:region-end.  They still do.
> 
> A basic prop of the Recommendation has been the inheritance of
> properties down the FO tree: not, as far as I have ever been able to
> tell, down the "FO tree that holds the content."  For instance, see my
> question
> http://lists.w3.org/Archives/Public/xsl-editors/2005JanMar/0060.html
> substantially unanswered in
> http://lists.w3.org/Archives/Public/xsl-editors/2005AprJun/0014.html
> which refers me to http://www.w3.org/2001/08/28-XSL-PR-DOC , 
> comment 20,
> item 3, a response to a message of 10 Jan 2001, which states, "The
> design approach taken for XSL was to have a simple inheritance model.
> Making this change would obviously introduce an exception to 
> this model. ...
> The consensus of the working group was to not introduce this 
> breaking of
> the inheritance as it is sometimes very useful and in the 
> cases where it
> is not what the stylesheet author wishes it is very easy to make an
> explicit specification ..."
> 
> That, of course, is also the case here.  Should an author be 
> unable, for
> reasons which escape me, to construct sufficient 
> fo:simple-page-masters
> to cover their requirements, and insist on overriding the
> reference-orientation and writing-mode on the 
> fo:simple-page-master they
> just specified for the current fo:page-sequence, there is always the
> option to create a top-level reference-area to contain the contents of
> fo:flow and fo:static-content.
> 
> The simple-page-master subtree has all the tools for specifying
> orientation and mode on every region, and that is the job of the page
> masters.
> 
> However, the editors have chosen discard the simple inheritance
> principle, but only in the fo:layout-master-set subtree, and only with
> respect to reference-orientation and writing-mode.
> 
> My suggestion is to remove most of this "clarification" from 
> the draft,
> along with from-page-master-region (still defined, 
> incidentally, with an
> optional argument which it is an error to use, and other 
> infelicities),
> and to replace that function with the following:
> <q>
> object from-page-sequence()
> The from-page-page-sequence function returns the computed value of the
> property for which the expression is being evaluated.
> 
> In XSL 1.1 this function may only be used as the value of the
> "writing-mode" and "reference-orientation" properties.
> 
> The computed value of the designated property is taken from
> fo:page-sequence ancestor of the formatting object on which 
> the function
> is being applied.  It is an error if the formatting object has no
> fo:page-sequence ancestor.
> </q>
> 
> fo:page-sequence will still need its new adornments of "7.21.3
> reference-orientation" and "7.29.7 writing-mode" among the set of
> properties applying.
> 
> Thanks for your attention.
> Peter
> 
> > Sharon Adler wrote:
> > 
> >>Peter,
> >>
> >>Yes you are correct in that we should not violate our rule to have
> >>inheritance down the  FO tree that holds the content.  We 
> do not believe we
> >>have properties that inherit from the fo:layout-master-set. 
>  Pulling a
> >>value using a property-value function is not inheritance.
> >>
> >>Thanks again for your comments and interest in XSL 1.1.
> >>
> >>Sharon
> >>
> >>
> >>
> >>
> >>Sharon Adler wrote:
> >>
> >>
> >>>Peter,
> >>>
> >>>I must apologize for taking so long to answer your comment 
> on XSL 1.1.
> >>
> >>We
> >>
> >>
> >>>value your comments and recognize that we need to introduce an
> >>
> >>inheritance
> >>
> >>
> >>>mechanism that inherits selectively from the layout rather 
> than down
> >>>formatting object tree.  However, we believe that this is 
> part of a more
> >>>extensive set of functionality we wish to introduce in the 
> next version
> >>
> >>of
> >>
> >>
> >>>XSL.  It is at that time that we will design 
> "layout-driven inheritance".
> >>>
> >>>Thank you for your interest in XSL 1.1.
> >>>
> >>>Sharon
> >>
> >>
> >>Sharon,
> >>
> >>Thank you for your response.  I have some feeling for the 
> difficulties
> >>the editors face with these questions.
> >>
> >>Given that the editors wish to retain a simple FO tree inheritance
> >>model, it seems to me important that such a principle not 
> be violated
> >>for the properties on the fo:layout-master-set subtree.  If 
> properties
> >>on, e.g., individual fo:region-body elements are inherited, 
> not down the
> >>fo:layout-master-set subtree, but through the 
> fo:page-sequence-master,
> >>then FO tree inheritance has been partially replaced by 
> layout driven
> >>inheritance.
> >>
> >>I much appreciate the efforts of the editors.
> > 
> > 
> > 
> 
> 
> -- 
> Peter B. West <http://cv.pbw.id.au/>
> Folio <http://defoe.sourceforge.net/folio/>
> <http://folio.bkbits.net/> <- the atTridged version
> ---
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Received on Tuesday, 7 February 2006 21:04:19 UTC