[Webkit-unassigned] [Bug 275197] Certain characters are not correctly rotated when using vertical writing mode

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=275197

--- Comment #2 from Xidorn Quan <xidorn-webkit at upsuper.org> ---
>From a read of CSS Writing Modes spec, it seems that
> the UA must determine the orientation of each typographic character unit by its Vertical_Orientation property: typesetting it upright if its orientation property is U, Tu, or Tr; or typesetting it sideways (90° clockwise from horizontal) if its orientation property is R.

and the character in question "ー" has Tr, so it does feel that WebKit is not doing it wrong. However, UAX #50 says
> Tr: Same as Tu except that, as a fallback, the character can be displayed with the code chart glyph rotated 90 degrees clockwise. 
and Tu is:
> Characters which are not just upright or sideways, but generally require a different glyph than in the code charts when used in vertical texts. In addition, as a fallback, the character can be displayed with the code chart glyph upright. 

so I suppose the CSS spec is talking about when such different glyph exists, one should render that upright. But when such glyph doesn't exist in the font (as likely this case), browser should probably rotate as if it's an R character.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20240606/33f22b7f/attachment.htm>