I suppose my question is how to make script-neutral ligatures in FontLab?
Defining a liga table for OpenType GSUB using FontLab 5 OpenType features panel.
Suppose I write
feature liga {
script latn;
sub I J by uniEB00;
sub Alpha Delta by uniEB01;
}
FL preview panel doesn't show either ligature (bug?) but choose Windows Notepad (Vista/7) and the result is as might be expected, the first ligature is applied, the second not applied (I and J are regarded as 'Latin', Alpha and Delta are not so the instruction is ignored).
If I rewrite as
script latn;
sub I J by uniEB00;
script grek;
sub Alpha Delta by uniEB00;
then both ligatures are shown in Notepad.
My specific issue is I have a script (Egyptian Hieroglyphs) which is not yet in the OpenType tag registry (
http://www.microsoft.com/typography/otspec/scripttags.htm). So as with greek in Latin, the ligature is not used but this time I have no script tag to make it work.
There are plenty of other scenarios where a script-neutral ligature would make sense.
I tried 'script dflt;' simply because I'm not clear what default means here! - but doesn't seem to help in my scenario. So the question is can I define script-neutral ligatures with FontLab/OpenType using liga or some other feature. If not what do I do when my script is not directly supported by OpenType?
Thanks
Bob Richmond
