ISSUE-40: style association for region has a special case not covered in 8.4

style and region

style association for region has a special case not covered in 8.4

TTML 1.0
Raised by:
Sean Hayes
Opened on:
In my continuing quest to understand the specification; I notice that style association for region has a special case not covered in 8.4. which is neither inline nor referential. Which to my mind complicates the specification, but which offers no additional functionality or notational convenience.

In general I think special cases should be avoided. And I’d like to propose removing <style> as an allowed child element of <region> unless someone knows of a good reason why they should be kept.

If we are to keep them, then I think this special case handling needs to be described, or at least referenced in section 8.4. Also apropos my earlier concern about chained referential styling; I think the problem may stem from the fact that we define a computed style specification set in <style> (and <region> although I think the latter should go) which contains the recursive algorithm; making 8.4.3 in fact redundant. But we don’t explicitly reference the computed style specification anywhere in 8.4.

I think editorially it would make much more sense if the exposition of computed style specification set and style association were all combined into 8.4 to extend the concept of the computed style specification set to a content element and remove the concept of style association. This would then tie in with 9.3.2 and style inheritance both of which reference the computed style specification set of a content element; a concept which is rather ill defined at the moment.
Related Actions Items:
Related emails:
  1. Agenda for TT telecon 9th April (from on 2009-04-09)
  2. [minutes] Timed Text Working Group Teleconference 20090220 (from on 2009-02-20)

Related notes:

Philippe Le Hégaret, 11 Dec 2008, 13:28:30

resolved in TTAF1-DFXP 20090415 update

Glenn Adams, 16 Apr 2009, 02:54:13

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