Unifying regions and non-regions layout algorithms

So, I have been to FOMS, and there was a lot of talk about WebVTT.

One of the things we discussed was how to integrate WebVTT Regions
more deeply into the spec, to not make it look like something bolted
on to the side. The different layout algorithms for the regions and
non-regions cases is a key component here.

I would like to see if we can make regions do nothing other than
constrain the space available to layout algorithm, so that rendering
in a region is equivalent to rendering in a smaller video element,
with the only exception that the vh/vw units would still be relative
to the entire video.

As a consequence, scrolling would become possible for any cue, in a
region or not. I haven't actually read the current spec, but I imagine
the following. First position the cue in its preferred location. If it
overlaps any other cue, it move it down until it does not overlap.
Then it would be moved up, pushing along with it as many cues as are
necessary to not cause (new) overlap. This "push" may be animated or
not, subject to author stylesheet and user preference.

The missing bit is how to switch between the two kinds of overlap
avoidance we end up with. Here I would suggest making this a cue-level
setting, and as a possible optimization have global and region-level
default for cues with no such setting.

Is this something people are interested in exploring?

(Many other issues were also discussed, but I think most are
orthogonal to what I've described here, and can be given separate
threads. If you would like to explore why I suddenly don't hate
regions, let's do that on another thread, assuming in this one that
regions will not just go away.)

Philip

Received on Thursday, 21 November 2013 22:54:30 UTC