Re: [css3-break] Fragment content displayed outside fragmentainer boundary

On 14/09/2012 00:58, Alan Stearns wrote:
> I think we should have a section in css3-break (perhaps 5.4?) that defines
> what happens when content in a particular fragment is displayed outside
> the fragmentainer boundary. Two instances of this are relatively
> positioned elements and line boxes at the top of the fragmentainer with a
> line-height insufficient to enclose the content. The test file in a recent
> css3-regions thread [1] shows non-interoperable behavior with multicol
> elements across all browsers.

> The question on relative positioning is whether the offsets apply relative
> to the fragmentainer or the fragmented flow. In the former solution, a
> line box shifted down at the bottom of a fragmentainer would appear below
> the fragmentainer box. In the latter solution the line box would appear at
> the top of the next fragmentainer in the fragmentation context. I think
> that the former solution is preferable.

Answering this seems fundamental, somehow.  Do we think of a rendered 
flow as being a subcanvas which gets pasted into fragmentainers and 
sliced at the fragmentainer boundaries?  Of do we think of the 
fragmentainers as being the container boxes of the flow, and hence 
overflow works as it normally does: it's relative to the box.

In the two examples you give, I don't think we want to push the 
bleeding-out content to the next fragmentainer.  It should "belong to" 
the first one, albeit rendered outside its boundary (or perhaps clipped, 
depending on 'overflow').

Note that this issue has some parallels with the ones being discussed in 
[1].

[1] http://lists.w3.org/Archives/Public/www-style/2012Oct/0565.html

Cheers,
Anton Prowse
http://dev.moonhenge.net

Received on Sunday, 28 October 2012 09:23:11 UTC