Post #1511914

Here comes the neat trick; #Fontra registers a message callback function, which gets called before and after each lookup is applied, and whenever #HarfBuzz is about to apply a lookup that the generated code would have been inserted before, Fontra steps in and modifies the glyph buffer and apply its own positioning logic. Then later lookups will be applied by HarfBuzz and modify the glyph positions as it would have happened with a fully compiled font. OK, it is a super nerdy and maybe a very few people can get why I’m so excited about it, but I’m really proud about it.