Native browser/CSS support for TTC (raw and/or within WOFF)?

Dear Webfonts WG members,

I'd like to ask:

Is there any work or current state regarding support for TTC as a 
webfont file format?

TTC is a potentially useful compression mechanism for font families. 
It's supported natively as desktop format on Mac OS X and Windows. 
Microsoft uses it primarily for CJK fonts but many of Apple's "simple" 
fonts which are bundled with Mac OS X and iOS come as TTCs. (In Apple's 
case, the switch was made in Mac OS X 10.6, I believe -- before that, 
Apple used their custom DFONT container, and before that, TrueType 
suitcases).

The TTC obviously has the advantage that an SFNT table whose content is 
identical across all members of a family (such as, for example, cmap or 
GSUB) can be stored once, while tables whose content is unique to each 
font are stored individually. I believe (though am not sure) that the 
structure sharing can even be done on a subtable level).

A potentially great compression mechanism, specific to SFNT, and 
potentially really useful for serving entire families as one file -- I 
think it would deserve being considered for webfont deployment.

Of course there's some caveats: since TTC is "one file" which stores 
several "subfonts", I believe @font-face might need to be modified 
somehow so that it allows selection of the subfonts.

So -- I wonder:
* Has any browser manufacturer tried to implement TTC support?
* Would it make sense?
* Am I right that the CSS @font-face clause would have to be extended 
somehow?
* Where is the current spec for TTC (or "OTC" as it's been proposed to 
rename for inclusion of CFF tables)?
* Are we aware of any publicly available tools to pack/unpack TTC files?

Oh, I just see that this topic has already been discussed in May 2012 on 
the CSS fonts list:
http://lists.w3.org/Archives/Public/www-style/2012May/0217.html
(Better view at:)
http://w3-org.9356.n7.nabble.com/css3-fonts-truetype-collection-td23567.html

...with no apparent conclusion.

As there does not seem to be much movement on the CSS3 Fonts list this 
year, and I believe the WebFonts WG is to some extent relevant to 
discussing this item briefly (primarily because we're focusing on 
compression now, and TTC *is* compression above all things), I'm raising 
it here.

Best,
Adam

-- 

May success attend your efforts,
-- Adam Twardoch
(Remove "list." from e-mail address to contact me directly.)

Received on Friday, 18 October 2013 14:36:11 UTC