Re: SVG <title> (was: SVG Feedback on HTML5 SVG Proposal)

Jonas Sicking:

>This I agree with though. It's also unclear to me that UAs are going
>to be able to do anything sensible with rich markup inside <title>
>given that the title is usually forwarded to the OS windowing system,
>and I've never heard of a windowing system that supports rich markup.

For a meaningful SVG document and a proper viewer only the
title of the root svg appears on top of the window.
There is no precise information what to do with title elements
if they appear within other elements. As the desc element and
the metadata element this is intended to contain alternative
text content, what should be accessible in a structured alternative
view. To give an indication, how the structure should appear, it is
obviously useful, that it is possible to structure the content of
those elements, what is possible in SVG1.1, but not in SVGT1.2
for title and desc, with the result, that authors have to move 
structured alternative text content in SVGT1.2 completely into 
the metadata element.
In most cases however, due to the functionality of a title or
heading, there will be not often substructure in the title element,
if used as a title element. This can be quite different for desc
and metadata, which can appear at the same places as title
can.

If we have a viewer, able to present both SVG and (X)HTML,
an author can for example put the html:h1-h6 heading into
the title element to indicate, which kind of heading the title
represents. In the related desc element the author can use
html:p, html:ul, html:abbr etc to provide a structured description
for any structure. 
On demand the viewer can provide an alternative
text view of the SVG document/fragment, using the indicated 
structure. 
Because in SVGT1.2 the RDFa attributes and role are
available, an author can alternatively indicate the role or
property of the title element: <title role="html:h1">...</title>
where 'html:h1' is a proper CURIE referencing the definition
of h1 in HTML4 for example. Alternatively another more
semantical expressive language than HTML can be used for 
roles or properties.
Both approaches can be pretty useful to improve the 
accessibility of SVG documents.

Received on Friday, 3 April 2009 10:13:11 UTC