Re: Last call comments on WOFF (9)

On Wednesday, January 12, 2011, 4:16:26 PM, Bert wrote:

BB> 9) The specification is called "1.0" but the actual format contains  
BB> neither a version number, nor a way to define extensions. It is  
BB> probably a good thing that there is only one WOFF format. It means  
BB> that a correct implementations cannot be incompatible with another  
BB> correct implementation, just because one was written later than the  
BB> other. But why then is there that "1.0" in the title of the spec?

BB> (The optional metadata has a version. Is that what the "1.0"  
BB> corresponds to? Although that part of the file can be ignored by many
BB> kinds of implementations, it is still a pity that there can, in the  
BB> future, be different formats that are all called WOFF, with the same  
BB> file extension, the same magic string, and, probably, the same MIME  
BB> type.)

Hello Bert.

It is true that many specifications forget to add a version number for the first one. Only when it comes time to make a revised version do they remember and create a 1.1 or 2.0 or whatever.

So this specification follows the recommendation in 'Architecture of the World Wide Web, Volume One' as follows:

"Good practice: Version information
A data format specification SHOULD provide for version information."

http://www.w3.org/TR/webarch/#versioning

thus, the specification has a version number.

You are correct that the WOFF header does not have a version number; we hope to be able to extend it in a backwards-compatible way.

You are also correct that the metadata *does* have a version number. it is possible that we would introduce new, backwards-incompatible metadata in the future. We don't plan to know, as the WG is chartered to avoid breaking backwards compatibility so is documenting  current deployed practice. But we leave tat open, hence a version number in the metadata instance. This is safe, because the metadata need not be read by font-using programs.

Please let us know if this response does not answer your comment.



-- 
 Chris Lilley   Technical Director, Interaction Domain                 
 W3C Graphics Activity Lead, Fonts Activity Lead
 Co-Chair, W3C Hypertext CG
 Member, CSS, WebFonts, SVG Working Groups

Received on Wednesday, 16 March 2011 17:50:28 UTC