I am trying to understand the OpenType features of Fira Code, but I’m slightly stuck on one point: there are quite a lot of instances of the word “LIG” in the calt
feature, and I’m unsure what that means or how it connects to the overall OpenType feature spec.
Here’s an example of the code:
lookup less_equal_equal_greater {
ignore sub less less' equal equal greater;
ignore sub less' equal equal greater greater;
sub LIG LIG LIG greater' by less_equal_equal_greater.liga;
sub LIG LIG equal' greater by LIG;
sub LIG equal' equal greater by LIG;
sub less' equal equal greater by LIG;
} less_equal_equal_greater;
Are these LIG
strings generated by GlyphsApp, or do you think they were written by the creator of the project? Are they something like a chained lookup for contextual substitution, or are they some kind of self-referential lookup, or something else? I’ve tried digging into the text of the .glyphs file, and I’ve tried converting to UFO, but I’m still having trouble understanding where those are established or what they’re connected to.
This is also something I’ve asked in the Fira Code repo, but I figured there might be some insights here.
Thank you so much for any perspectives!