Re: DOCBOOK-APPS: How to select <imageobject> alternative in <mediaobject>?

[Nicholas Atkinson <nik@casawana.com>]

I'm using the 1.60.1 distro of the xsl stylesheets and have been
experimenting with alternative imageobjects in a mediaobject for html and
fo.

In short it doesn't work.  I have searched through the stylesheets and have
found that though the parameter "use.role.for.mediaobject" is documented and
is included in files such as param.xsl, it doesn't appear at all in any of
the stylesheets proper such as graphics.xsl!

I am wondering if this feature has been backed out or been delayed for a
future distro or what?

It's a very good feature, but where can I get it?!

nik


----- Original Message -----
From: "Bob Stayton" <bobs@caldera.com>
To: "Jeff Beal" <jeff.beal@ansys.com>; <docbook-apps@lists.oasis-open.org>
Sent: 06 December 2002 23:51
Subject: Re: DOCBOOK-APPS: How to select <imageobject> alternative in <med
iaobject>?


> Based on the feedback I got about this, I went ahead and
> checked in changes to the XSL stylesheets to support the
> use of the role attribute to select one of several
> possible imageobjects.
>
> This will let you put several imageobjects (or other
> *objects) in a mediaobject container.  If one object
> has a role="html" attribute, then that one will be used
> for HTML (and XHTML) output.  If there are more than one object
> with that role, then the selection process proceeds as
> before but just with those objects.  If none of
> the objects has that role, then it falls back to picking
> the first suitable object.
>
> For fo output, an object with role="fo" will be used in
> a similar manner.
>
> Per Jeff Beal's suggestion, I added a
> 'preferred.mediaobject.role' parameter to let you
> set your own name instead of 'html' or 'fo'.
> If that parameter is not blank and there is an object
> with that role value, then it is used.  If that parameter is
> not blank and there is no object with that role, then
> it falls back to trying to select 'html' or 'fo' objects.
> Otherwise it falls back to picking the first suitable
> object.
>
> Per Jirka's suggestion, I added a 'use.role.for.mediaobject'
> parameter switch to turn off the whole process of
> considering role in selecting the object.  Then it takes
> the first suitable object.  This can be used with
> profiling on the role attribute to select the object in the
> profiling stage.
>
> These changes will be in the next XSL distribution.
>
> Bob Stayton                                 400 Encinal Street
> Publications Architect                      Santa Cruz, CA  95060
> Technical Publications                      voice: (831) 427-7796
> The SCO Group                               fax:   (831) 429-1887
>                                             email: bobs@sco.com
>
>
> On Tue, Nov 26, 2002 at 09:17:57AM -0500, Jeff Beal wrote:
> > I agree that role is the best attribute for the author specifying which
> > object to use for which output.  I don't think that simply 'html' and
'fo'
> > will be able to satisfy every condition, though.  For example, we
support a
> > wide variety of platforms and many of our UNIX users use an X Windows
> > emulator to run our application from their Windows desktop.  Using the
> > audioobject would not work, simply because sound doesn't work in that
> > configuration.  However, we may want to use an audioobject for our
Windows
> > users.  There are probably several other examples.  (e.g. different
image
> > support between XEP and FOP)
> >
> > I think that if you add a "preferred.mediaobject.role" parameter, we can
> > modify the selection algorithm as follows:
> >
> > 1) Look for an object with "@role = $preferred.mediaobject.role"
> > 2) Look for an object where the role matches the output (html or fo)
> > 3) Pick the first object with either role="all" or no role attribute
> > 4) Look for a textobject
> >
> > Jeff Beal
> >
> > -----Original Message-----
> > From: Bob Stayton [mailto:bobs@caldera.com]
> > Sent: Monday, November 25, 2002 11:25 PM
> > To: docbook-apps@lists.oasis-open.org
> > Subject: Re: DOCBOOK-APPS: How to select <imageobject> alternative in
> > <mediaobject>?
> >
> >
> > The mediaobject element can contain more than one
> > imageobject element, with the intent being to use
> > one from the set for a given output.  But
> > there currently isn't an easy way of designating this
> > particular imageobject for HTML output and that
> > one for FO output.
> >
> > I suggested in a previous message that role="html" or
> > role="fo" in each imageobject could be used, with a
> > stylesheet customization to act on the role value.  I'm
> > wondering if this method would be appropriate as a standard
> > feature of the stylesheets? That is, should the stylesheets
> > designate the role attribute as the method to select
> > which imageobject to use?
> >
> > Let me be clear that this is not a change to the DTD, but
> > just a convention to be used with Norm's XSL stylesheets.
> >
> > There doesn't seem to be another available attribute that
> > would be appropriate.  And I'm guessing that any profiling
> > would probably be done on the role attribute in
> > mediaobject, rather than the individual imageobjects within
> > it.
> >
> > But I'd like to hear what others think.
> > Would this be useful?  Is there a better way to do it?
> >
> >
> > Bob Stayton                                 400 Encinal Street
> > Publications Architect                      Santa Cruz, CA  95060
> > Technical Publications                      voice: (831) 427-7796
> > The SCO Group                               fax:   (831) 429-1887
> >                                             email: bobs@sco.com
>
> --
>
> Bob Stayton                                 400 Encinal Street
> Publications Architect                      Santa Cruz, CA  95060
> Technical Publications                      voice: (831) 427-7796
> The SCO Group                               fax:   (831) 429-1887
>                                             email: bobs@sco.com