Re: Anything to discuss during our telcon tomorrow?

They are as unambiguous as the font vendor chooses to make them, yes. But that’s really no different than any other PostScript name, which are generally expected to be unique across a family.

> On Dec 14, 2016, at 3:49 PM, Roderick Sheeter <rsheeter@google.com> wrote:
> 
> Not unambiguously though, as Jonathan noted. Each font in a collection can have the same names or they could share 'name' completely. Clearly we want myfont.ttc#index#postscriptname and ... can we collect collections?
> 
> It's a pity because #postscriptname-of-instance does seem nicer than having to list axis positions. However, #postscriptname that doesn't actually match all the things you can give postscript names seems a tad sketchy. #postscriptname[index within things having that name]!
> 
> 
> On Wed, Dec 14, 2016 at 3:37 PM, Ned Holbrook <ned@apple.com <mailto:ned@apple.com>> wrote:
> Named instances can also specify a PostScript name, which would allow selection even within a collection.
> 
>> On Dec 14, 2016, at 1:51 PM, Jonathan Kew <jfkthame@gmail.com <mailto:jfkthame@gmail.com>> wrote:
>> 
>> On 14/12/2016 21:01, Chris Lilley wrote:
>>> 
>>> 
>>> On 2016-12-14 15:23, Roderick Sheeter wrote:
>>>> Cool. Hey, would #postscriptname work for any postscript name? In
>>>> particular, for accessing a named instance in a variation font?
>>> Huh, interesting. I hadn't thought about that one!
>>> 
>>> I think the plan is to access anywhere along an axis by putting the axis
>>> values on the @font-face descriptors. So named instances are not privileged.
>> 
>> I was going to say it should: named instances should be available by name. But there's a complication with that. In principle, you could have a collection containing multiple variation fonts, and multiple named instances within each of them. Those names might not be unique. So it'd be perfectly reasonable (I think) to have:
>> 
>>  MyFamily.ttc
>>    face: MyFamily-Upright
>>      instances: Light, Regular, Bold, Black
>>    face: MyFamily-Italic
>>      instances: Light, Regular, Bold, Black
>> 
>> as instance names are meaningful only within a single (variation) face.
>> 
>> Therefore, while I think it is useful to provide a means to access named instances (without having to discover and specify their actual variation coordinates), this needs to be distinct from the use of the PostScript name to select a face within a collection.
>> 
>>> 
>>> Would non-variation-aware processors be able to get at named instances?
>>> (for TrueType glyhs - clearly they would not be able to for CFF2)?
>>> 
>> 
>> I wouldn't expect so. A named instance is just a name for a specific set of variation-axis values; but to apply those values, the rasterizer needs to know how to process variations.
>> 
>>>> 
>>>> On Wed, Dec 14, 2016 at 11:40 AM, Chris Lilley <chris@w3.org <mailto:chris@w3.org>
>>>> <mailto:chris@w3.org <mailto:chris@w3.org>>> wrote:
>>>> 
>>>> 
>>>> 
>>>>    On 2016-12-13 23:14, Levantovsky, Vladimir wrote:
>>>>> 
>>>>>    On a related subject – there have been updates on the top-level
>>>>>    font media type registration. Chris Lilley has been busy at work
>>>>>    (thank you Chris!) addressing some of the issues reported by the
>>>>>    IETF-assigned reviewer,
>>>>> 
>>>>    all of them, I hope :)
>>>>> 
>>>>>    and the new version of the document has been created as a result.
>>>>>    Please review and send you comments, if any. The details on the
>>>>>    document progression can be seen at
>>>>>     https://datatracker.ietf.org/doc/draft-ietf-justfont-toplevel/ <https://datatracker.ietf.org/doc/draft-ietf-justfont-toplevel/>
>>>>>    <https://datatracker.ietf.org/doc/draft-ietf-justfont-toplevel/ <https://datatracker.ietf.org/doc/draft-ietf-justfont-toplevel/>>
>>>>> 
>>>>> 
>>>>> 
>>>> 
>>>>    Of note, the most recent couple of drafts have a new fragment
>>>>    syntax for collections (both font/collection and also font/woff2).
>>>>    Ken Lunde pointed out that the numeric fragment syntax was
>>>>    brittle, as new fonts are typically inserted rather than appended
>>>>    into a collection. Instead, a fragment syntax using the PostScript
>>>>    name is specified.
>> 
>> There is a downside to using PS names to identify fonts within a collection, though: it requires the UA to decode/parse all the faces in order to look at their names. The numeric index allows a UA to process only the single face that is actually being requested.
>> 
>> JK
>> 
>>>> 
>>>>    This syntax was already in use in CSS3 Fonts, for referring to
>>>>    locally installed fonts rather than downloaded ones. For use as a
>>>>    fragment, the only complication is that six characters are allowed
>>>>    in PostScript names and disallowed in fragment identifiers. They
>>>>    have to be percent-escaped in the fragments.
>>>> 
>>>>    An additional benefit is that the syntax is more human readable.
>>>>    To get at Foo Bold in a collection (or woff2 of a collection)
>>>>    called bar, the syntax is bar.woff2#Foo-Bold for example, not
>>>>    bar.woff2#3 or whatever.
>>>> 
>>>>    As far as I know, no browser or html-to-pdf formatter has support
>>>>    for collections. So there is no web compat issue. The new syntax
>>>>    will be more usable, and completes what is needed for us to use
>>>>    collections in woff2.
>>>> 
>>>>    --
>>>>    Chris
> 
>