Consider adding support for tts:rubyAlign="spaceAround"

[palemieux]

This allows ruby text to look more natural when rendered against long bases. See illustration.

[css-meeting-bot]

The Working Group just discussed Consider adding support for tts:rubyAlign="spaceAround" imsc-vnext-reqs#30, and agreed to the following:

• SUMMARY: Research continuing, consider adding all values if CSS supports them.

The full IRC log of that discussion

<nigel> Topic: Consider adding support for tts:rubyAlign="spaceAround" imsc-vnext-reqs#30
<nigel> github: https://github.com//issues/30
<nigel> Pierre: I just opened this after working on it for a couple of days.
<nigel> .. The illustration is the best thing to look at.
<nigel> .. Today the only thing that's allowed is center, which is the bottom illustration.
<nigel> .. The feedback I received is that it doesn't work when the ruby base is very long, because
<nigel> .. bunching up the ruby text makes it less easy to read.
<nigel> .. The space around example (top example) is preferred.
<nigel> Cyril: No objection, but the examples .. are they from a real example?
<nigel> Pierre: I'm told this happens in real subtitles.
<nigel> Cyril: Ok, I have no objection.
<nigel> Pierre: I'd like more information before finalising my own opinion. Cyril, I'll try to get as
<nigel> .. many real examples as possible.
<nigel> Cyril: I'll check with Netflix if we have any opinions and examples too.
<nigel> Pierre: Thank you. Also there's a subtle difference between spaceAround and spaceBetween.
<nigel> .. Right now my research says adding spaceAround would address most of the concerns.
<nigel> .. What I hear this morning is there are no immediate concerns to allowing it.
<nigel> Cyril: To be on the safe side we should maybe implement all values.
<nigel> .. Once you've implemented spaceAround and spaceBetween then adding withBase is not
<nigel> .. that difficult.
<nigel> Pierre: Yes, I don't know what CSS supports other than spaceAround, which is the initial value,
<nigel> .. so seems pretty safe.
<nigel> Cyril: Do you prefer restricting IMSC 1.1 to a limited set of values and then increasing them
<nigel> .. later if there is CSS support.
<nigel> Pierre: I'd rather go down that path, it avoids misuse. It's not an easy question.
<nigel> .. Do please ask the question Cyril about supporting all of them. If CSS supports all of them
<nigel> .. then that makes it a lot easier in my mind.
<nigel> SUMMARY: Research continuing, consider adding all values if CSS supports them.

[palemieux]

CSS supports start, center, space-between, and space-around.

I have not seen requirements for anything beyond space-around and center.

[css-meeting-bot]

The Working Group just discussed Consider adding support for tts:rubyAlign="spaceAround" imsc-vnext-reqs#30, and agreed to the following:

• RESOLUTION: Support `tts:rubyAlign="spaceAround"` in IMSC v1.1

The full IRC log of that discussion

<nigel> Topic: Consider adding support for tts:rubyAlign="spaceAround" imsc-vnext-reqs#30
<nigel> github: https://github.com//issues/30
<nigel> Pierre: I've implemented space-around in imsc.js and it works in the sense that it is no
<nigel> .. worse than any other alignment feature, in that only Firefox supports it properly.
<nigel> .. Supporting space-around is no harder than supporting center.
<nigel> .. I've received feedback from Japanese contacts that space-around is a must so my
<nigel> .. recommendation is to add it.
<nigel> Nigel: Any counter-views?
<nigel> Cyril: When you say "supported" I think at least in CSS it has the capability to do spacing
<nigel> .. on the base text also so if the ruby annotation is bigger than the base text then the
<nigel> .. spacing is added to the base text. Is that something you support?
<nigel> Glenn: That behaviour is implementation dependent in TTML2 at the moment. We don't
<nigel> .. say what an implementation should do at this point.
<nigel> Pierre: I did not try that but I can try it right now.
<nigel> Cyril: I don't know if this is the right behaviour but the CSS spec has diagrams showing that.
<nigel> Pierre: No, it doesn't happen in Firefox I don't think.
<nigel> .. Oh no, it does add spacing, that's correct.
<nigel> .. We could put it as at risk. I'm told under no uncertain terms that when the base text
<nigel> .. is long and the narrow ruby annotations then not having space-around is bizarre.
<nigel> Cyril: I'm fine with that.
<nigel> PROPOSAL: Support `tts:rubyAlign="spaceAround"` in IMSC v1.1
<nigel> Nigel: Any objections?
<nigel> RESOLUTION: Support `tts:rubyAlign="spaceAround"` in IMSC v1.1