RE: [CSS21] zindex.html E.2 issue: ordering contradictions

On Sunday, March 06, 2011 8:30 AM Peter Moulder wrote:
> Note that this issue is mostly editorial (even if requiring more thought to fix
> than most editorial issues), i.e. I think there's agreement on the essentials of
> the correct behaviour (which I suspect corresponds to the behaviour that
> Anton Prowse describes), and it's mostly just a matter of making sure that
> appendix E actually corresponds to that behaviour.
> 
> On Sun, Nov 07, 2010 at 10:22:58AM +0100, Anton Prowse wrote:
> > On 05/11/2010 04:28, Peter Moulder wrote:
> >
> > >If I understand correctly, zindex.html as currently written includes
> > >some items (say the background image of element X) more than once:
> > >various places in the list include "all [qualifier] descendents [of
> > >E]", which typically includes descendents of some different E that's
> > >also included in the painting order.
> >
> > I believe that the issues you're raising in your post are a subset of
> > those I raised at the start of my campaign to get 9.9.1 changed.[1]
> 
> It may well be that Anton's suggested changes (if applied to appendix E and
> not just §9.9) would fix the problem.  E.g. introducing a term like Anton's
> pseudo–stacking context may well be useful as part of the fix.
> 
> If there's concern that this report may merely duplicate issues Anton has
> raised, then I'm happy to wait until those issues are addressed and modify
> (or retract) this issue report once a revised version of appendix E is available.
> 
> (Note of course that this only applies if appendix E is in fact changed as part
> of that: obviously no change to §9.9 alone could be enough to remove any
> contradictions within appendix E.)
> 
> > In particular, 9.9.1 states: [...]
> 
> Similarly, the content of chapter 9 is irrelevant to whether there are
> contradictions within appendix E.  It may be that chapter 9 gives a clue as to
> what the correct wording in appendix E should be, but appendix E would still
> need to be changed.
> 
> > What we're really doing when compositing the document is determining
> > the dependants of each stacking context and pseudo–stacking context
> > (terms which I defined in my original proposals (see [1])), and then,
> > working upwards from the innermost (pseudo–)stacking context,
> > compositing said context according to the rules of E2 and treating any
> > already-composited context as atomic.
> > [...]
> > Not so, because ...
> 
> That may well be what we want the text to say, and may be what the text
> would say under Anton's proposed edits; however, it's not what the Dec7
> working draft says, which does have the problem.
> 
> > There is no "double treatment" of any box.
> 
> I believe I showed in my previous post that appendix E in the Dec7 working
> draft does indeed give double treatment to some boxes, that section E2
> does in fact include some boxes in more than one float (etc.).
> 

Thank you for your feedback. The CSSWG resolved not to make these changes to the CSS 2.1 specification[1]. We will be reevaluating this issue for future versions of CSS. 

Please respond before 18 March, 2011 if you do not accept the current resolution.

[1] http://w3.org/TR/CSS

Received on Wednesday, 16 March 2011 18:25:01 UTC