[ft-devel] af_latin_blue_chars?

[Ian Britten]

Hi all,
[ FT 2.3.9 ]
Can someone give me a simplistic description of what
af_latin_blue_chars, af_latin_metrics_init_blues(), etc, are for?

Background:
I have a custom font driver (for our custom font format), and
found a strange sequence of (extra) characters being requested,
(Via my FT_Slot_LoadFunc) when drawing text through Cairo.
Debugging the requests took me to the 'blue' stuff, and I was
just kindof wondering what it was for.  If it was trying to
obtain metrics for the entire Face, I'd guess it would just use
the characters [A-z][a-z],etc, but those strings seem pretty
unique/distinct.
[ Note the string "xzroesc" seems to be a duplicate, but maybe
that's intentional... ]

Anyways, I have no particular problem - Just trying to learn a
bit more about FT...
Thanks for any info, and keep up the great work!
Ian