John Hudson <tiro at tiro dot com> wrote: > It should be noted that using ZWJ is a valid way to encode the > desirability of a ligature in plain text, but it is far from being a > guarantee of displaying such a ligature. There are a lot of fonts out > there with glyph substitution lookups that will correctly display > something like a ct ligature using layout features (discretionary, > controlled by the user) in OT savvy apps like Adobe InDesign, but > will do so only for the sequence c+t. Ironically, the sequence > c+ZWJ+t is more likely *not* to display as a ligature, since the ZWJ > interferes with the sequence recognised by the font lookups.
Using ZWJ to control ligation is admittedly a new concept, and it may not have been taken up yet by many vendors, but that seems like a really poor reason to discourage the Unicode approach. Proprietary layout features in OT-savvy apps like InDesign might get the job done, but wouldn't it be better if app vendors and font vendors would follow the Unicode Standard recommendation? You never know, it might even reduce the number of requests to encode ligatures. -Doug Ewell Fullerton, California
