Re: CSS and East Asian Width

On Thu, Dec 17, 2015 at 6:44 PM, Bobby Tung <bobbytung@wanderer.tw> wrote:
> > Xidorn Quan <quanxunzhen@gmail.com> 於 2015年12月17日 下午3:54 寫道：
> > I don't really see anything which should be addressed but remains
> > unspecified in CSS in the section you mentioned. Could you point out
> > exactly which sentences do you think of?

Asides from ASCII image, I was originally think of "二○一五" but I later
realized it's a mistake (The correct character to use is U+3007 (and
you get "二〇一五").

The next common pitfall is the infamous middle dot, which is discussed
in length in [1].

[1] https://lists.w3.org/Archives/Public/public-zhreq/2014Dec/0000.html

Other common characters are symbols like U+203B ※.

> May it relate to CSS Font Module level 3 East Asian font variant?
>
> https://drafts.csswg.org/css-fonts/#font-variant-east-asian-prop

It looks like a property that would affect glyph selection (from an
OpenType font with multiple glyphs point to the same codepoint) by
allowing web authors to target the full-width variants (OpenType
feature: fwid)? Are we looking at handling ambiguous width *entirely*
in OpenType feature instead? I don't think there is a problem on top
of my head, other than web authors has no knowledge of the character
width handling of the UA font.

Another OpenType feature to be make use of is probably "locl". Web
author would control the width of the characters indirectly by setting
content language (HTML "lang" attribute).

I don't know if that actually overloads the meaning of OpenType
features, or something font vendor would object.

This might also avoid the problem where to implement a "treat
ambiguous-width characters as double width" feature CSS would
inevitably have change the font selection scheme used in the
"font-family" property.

Thanks for the pointer!


Tim

Received on Thursday, 17 December 2015 18:35:18 UTC