Re: WebVTT spec

On Tue, Mar 26, 2013 at 9:27 AM, Ian Hickson <ian@hixie.ch> wrote:

> On Tue, 26 Mar 2013, Silvia Pfeiffer wrote:> I am assuming a
> JavaScript-only use of TextTrack() constructor and
> > TextTrackCue(). And yes, you are right: the format is much better suited
> > to being defined in the TextTrack() constructor rather than in a
> > TextTrackCue().
>
> I don't understand the relevance of constructors at all here.
>

Actually, the constructors were the key point of my problem. I think I've
got it now: you wouldn't create a TextTrackCue() because it's only a
virtual class, you would only create a WebVTTCue(). Thus, the format is
clear and there is no need to specify it further.

I've understood now.


> > The definition of the WebVTT data model says of WebVTT cues:
> > >
> > > # The associated rules for updating the text track rendering of WebVTT
> > > # text track cues are the rules for updating the display of WebVTT text
> > > # tracks.
> >
> > When you are doing it all in script, there is no WebVTT file and no
> > means to specify that the cue that you are providing is in the format of
> > a WebVTT cue.
>
> What's that got to do with anything?
>
> The WebVTTCue constructor ("new WebVTTCue()") creates a WebVTT cue (if you
> want, you could make this more explicit by changing "Create a new _text
> track cue_" to "Create a new _text track cue_ that is a _WebVTT cue_",
> and then make "WebVTT cues" in the data model section a <dfn> for xrefs).
>
> When you provide a WebVTT cue's object (WebVTTCue) to addCue(), addCue()
> checks what kind of cue it is, and based on that either rejects the cue or
> sets the text track to be a text track for that kind of cue.
>

Yup, that resolves it. Sorry about the confusion - I really didn't think
this through.


> > A WebVTT cue isn't a TTML cue. Why would distinguishing them be
> > > difficult?
> >
> > Again: assuming you do it all in script: you create a text track using
> > TextTrack() then you add a cue using TextTrackCue() and addCue().
>
> I'm not sure what you mean by TextTrack() and TextTrackCue().
>
> Right now in the specs the only pure-script way to create a cue of any
> format by invoking the WebVTTCue constructor ("new WebVTTCue()"), which
> returns a WebVTT cue. The only way to create a TextTrack object is using
> the addTextTrack() method on HTMLMediaElement.
>

Right. Problem solved, thanks!


> On Sun, 24 Mar 2013, Silvia Pfeiffer wrote:
> > > >
> > > > I've copied the spec text to a new HTML file and uploaded it to the
> > > > W3C Mercurial repository - it's now staged at:
> > > >
> > > >
> https://dvcs.w3.org/hg/text-tracks/raw-file/default/webvtt/webvtt.html
> > >
> > > Do you have a diff of this spec to the existing one? I'd like to make
> > > sure that the diff is zero before we actually hand things over.
> >
> > Are you after a diff on the html level or something else? I just copied
> > all the text from the whatwg source file that was between <!--START
> > webvtt --> and <!--END webvtt --> markers, then applied the ReSpec
> > boilerplate.
>
> I mean a diff of this:
>
>    https://dvcs.w3.org/hg/text-tracks/raw-file/default/webvtt/webvtt.html
>
> ...and this:
>
>    http://dev.w3.org/html5/webvtt/
>
> It looks like there's all kinds of errors right now, for example compare
> these two sections:
>
>
> https://dvcs.w3.org/hg/text-tracks/raw-file/default/webvtt/webvtt.html#webvtt-cue-text-dom-construction-rules
>    http://dev.w3.org/html5/webvtt/#webvtt-cue-text-dom-construction-rules
>
>
Yes, I think that's a style issue.


> Also the new style sheet you have applied is missing all kinds of things.
> For example, the table in the section above is all misstyled, domintro
> blocks are unstyled, the spacing in the IANA section is all off, broken
> cross-references and incomplete sections aren't highlighted, etc.
>

Right - I haven't fully applied all the ReSpec functionality yet. Thanks
for pointing these out.


Also you're referencing a version of HTML with all kinds of errors, and
> you seem to have changed the spec's status from "Standard" to "Working
> Draft" which seems like a regression.
>

Yes, that part I have no idea how to deal with. David will have to provide
help there.

Thanks - I'll give the formatting another go. Clearly, it's not ready yet.

Silvia.