[css-text-decor] Emphasis marks and combining characters



"The marks are drawn once for each character. However, emphasis marks 
are not drawn for characters that are:
     Word separators or that belong to the Unicode separator classes 
(Z*). (But note that emphasis marks are drawn for a space that combines 
with any combining characters.)
     Characters belonging to the Unicode classes for control codes and 
unassigned characters (Cc, Cf, Cn)."

presumably these marks should not be displayed for combining characters 

thinking a bit further, i wonder what happens for syllables in complex 
indic and SE Asian scripts. Grapheme clusters may account for some 
associations, but not those where multiple grapheme clusters comprise a 
single syllable.  Perhaps these emphasis marks are not really intended 
to be used with complex scripts - if that's the case, perhaps we should 
add a note to that effect.

Note, btw, that there is a possible requirement for this kind of 
emphasis in Tibetan (see 
http://w3c.github.io/tlreq/#emphasis_and_highlighting), but the mark is 
centered across the syllable rather than tied to a single character.  Do 
we have any thought of catering for that in future versions of the spec?


Received on Monday, 23 November 2015 09:45:59 UTC