Re: [css-ruby] What does it mean for "ruby-position: inter-character" to force writing-mode to be vertical?

On 12/15/2014 11:59 AM, Glenn Adams wrote:
> On Mon, Dec 15, 2014 at 11:00 AM, Daniel Holbert <dholbert@mozilla.com
> <mailto:dholbert@mozilla.com>> wrote:
[...]
>     In this case, the desired inter-property influence seems to be:
>        For any element with a computed "display" of
>        "ruby-text-container" *and* a computed "ruby-position"
>        of "inter-character", the UA must force the computed
>        "writing-mode" to be $SOME_VERTICAL_WRITING_MODE.
> 
> 
> This complexity could easily be avoided if the spec says "if
> ruby-position is inter-character, and writing-mode is not a vertical
> mode, then treat ruby-position as if the value 'initial' were specified".
> 
> There is no reason ruby position should be forcing writing mode.

This suggestion (making "inter-character" only work if the writing-mode
happens to be vertical) seems problematic for several reasons:

 (1) It will cause author confusion and provide broken behavior by
default. As I understand it, "inter-character" is to be used with
horizontal base text -- at least, that's the example in the spec -- so,
unless the author knows to specify a vertical writing-mode specifically
on the annotations, "inter-character" just won't work.

(2) It seems like inter-character's validity could vary between sibling
"ruby-text" boxes, which (depending on how your suggestion is
interpreted) could mean the ruby-position would change back & forth
within a given ruby-text-container.  I'll clarify, because there are
several boxes in play here:
 - "ruby-position: inter-character" applies to the ruby-text-container.
 - But the annotation text itself is inside of a "ruby-text" box,
*inside* of that container.
 - SO: if there's no writing-mode-forcing, then each "ruby-text" box can
specify its own "writing-mode" and make its text vertical/horizontal,
which can make "inter-character" on its parent seem valid or invalid for
that particular ruby-text box. (and this could vary between sibling
text-boxes.)

Received on Monday, 15 December 2014 22:34:47 UTC