Re: Hanging Punctuation Questions

On Sat, Mar 5, 2016 at 6:39 AM, David Hyatt <hyatt@apple.com> wrote:

> (6) The WG resolved overflow is ink overflow. I think it should be
> scrollable overflow. I can elaborate on this if needed, but it’s a
> selectable character that has to be reachable when edited and cut/copied
> etc. Any designer is going to leave space for hanging punctuation if they
> turn it on, so fears of scrollbars are unfounded IMO. It’s also an annoying
> amount of additional work to treat that as ink overflow when the common
> sense implementation just moves the line box (and line boxes are scrollable
> overflow obviously). This is similar to text-indent, which creates layout
> overflow when negative, so it’s not clear to me why hanging punctuation
> can’t behave the same way.
>
> Regardless of ink vs. layout, the designer has to leave space for hanging
> punctuation if they decide to use this feature, so I would prefer we go
> with the more common sense implementation choice.
>

The reason that we decided to make it an ink overflow is that, many
punctuations in CJK are full-width while their ink just takes less than
half of the space. It is especially true for Simplified Chinese and
Japanese, for stop and comma. It means that, it is completely fine to have
a space which is enough to show the ink but not enough from the metrics.
Making hanging punctuation scrollable overflow could confuse people in this
reasonable usecase.

- Xidorn