At 09:22 11/2/2002, Thomas Lotze 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.In the meantime, I found out about ZWJ (this one could be mentioned in the FAQ, BTW). Now I agree that it is preferable not to use ligature code points in documents. However, this isn't a matter of principle, it just avoids having to resolve ligatures into their constituents when, eg, searching documents, and requires instead ignoring the ZWJ, which is easier to do.
I think some font developers will begin including additional ligature lookups using ZWJ, but I suspect that the majority will not. Most font developers are focused on markets in which users do not encode ligature preferences in plain text, and in which the use or non-use of ligatures is a typographical decision independent of the authorship of a document. Most font developers have never heard of ZWJ. Nor, come to think of it, have most users.
John Hudson
Tiro Typeworks www.tiro.com
Vancouver, BC [EMAIL PROTECTED]
It is necessary that by all means and cunning,
the cursed owners of books should be persuaded
to make them available to us, either by argument
or by force. - Michael Apostolis, 1467
