[MPEG-OTSPEC] Hints, TT and CFF (was: Re: Proposal to make OFF complete)

[Ken Lunde]

Dave,

You wrote:

>>> Haha, awesome!
>>> 
>>> I must admit my ignorance with regards to CFF2, but, isn't one of the major features of CFF2 that hints can vary? 
>> 
>> Major in what way? Yes, CFF2 hints can vary. Also yes, TT-based varfonts' hints can also vary.
> 
> Major in that Ken's fonts don't take advantage of it, and yet a "business case" for CFF and CFF2 that I've heard is that rendering is superior because of the hinting model.

The fonts for the three Source Han typeface families that I architected and built while at Adobe, along with the fonts for the two clone Noto CJK typefaces that I built and delivered to Google, definitely include 'CFF' tables that were carefully hinted, in terms of specifying ideal stem values and alignment zones for the multiple FDArray elements (aka hint dictionaries). I know, because I did all of the work to determine the ideal values.

In addition, the FDArray elements that include glyphs for ideographs (named "<font>-Ideographs") and bopomofo (named "<font>-Bopomofo") had global coloring (aka counter-control hints) applied, which was performed by a command-line tool named addGlobalColor. This command-line tool is not included in AFDKO.

I never had an opportunity to carefully hint any 'CFF2' tables.

Unless Google stripped the hints from the 'CFF' tables as a post-process, the Noto CJK fonts are fully-hinted, to include global coloring for the glyphs for ideographs and bopomofo.

Regards...

-- Ken