Re: [css3 fonts] font-specific features

On Sep 27, 2010, at 11:30 AM, Thomas Phinney wrote:

> On Mon, Sep 20, 2010 at 8:15 PM, John Daggett <[email protected]> wrote:
>> Tal Leming wrote:
>>> If so, how does the author specify a particular index from a GSUB
>>> Lookup Type 3 for a styleset?
>> 
>> If by this you mean some form of stylistic set that allows multiple
>> values per feature tag (e.g. ss04=7) then that's not supported by the
>> current proposal, an author would need to use the low-level
>> font-feature-settings property.  I think this is probably more
>> relevant to fonts with character variants that map all variants for a
>> given character to a common cvNN feature tag (e.g. all variants of
>> alpha map to cv01).
> 
> There are a number of OpenType layout features that do take an
> explicit index argument to pick a specific glyph out[put from several
> options. Stylistic sets ('ssXX') are not one of them, but stylistic
> alternates ('salt') and even swashes ('swsh') are among the ones that
> do.

Yes. I was thinking through edge cases. The spec may say that ssXX doesn't support Lookup Type 3, but the spec says a lot of other things that aren't followed. :-)

I think that the proposed syntax is fine.

Tal