[css3-ruby] [css3-text] Position values and before/after definitions in LR vertical writing mode

In top-to-bottom horizontal writing mode (English, most other scripts) and in
right-to-left vertical writing mode (CJK), the "before" side and the effective
top of the line (wrt vertical alignment, glyph rotation, etc) coincide.


But in left-to-right vertical writing mode (Mongolian), the "before" side and
the effective top of the line do not coincide. See the illustration here:

The "before" side of a line is to the left. The "top" (ascender) side of a line
is to the right.

If ruby-position and text-underline-position use "before" to mean "on the right
side of the line" in vertical text, then we have a problem where "before" means
different sides of an item depending on what property is involved.

Either the definitions should be updated to depend on whether the block flow
is right-to-left or left-to-right, or the keywords should be changed to something
else to avoid a conflict in meaning. I suggest the latter, since I suspect that
the current definitions are the ones that are typographically relevant.

However, I haven't encountered any really good pairs of keywords. (Koji and I
are using "above" and "below" for now.)

Richard, do you have any thoughts on this?


Received on Sunday, 26 September 2010 14:15:47 UTC