RE: [css3-fonts] humane 'unicode-range'

This is in reply to a little old thread as this was marked as an issue in the spec[1].

One use case that came up in my mind is to switch fonts for UAX #11 [2] EAW=A code points.

EAW=A contains mostly punctuation and symbols that were unified. I think there are cases where authors want:
* CJK fonts for EAW=A|F|H|W
* Latin fonts for EAW=N|Na

One famous example for EAW=A is U+2026 HORIZONTAL ELLIPSIS; ellipsis are at baseline in Latin fonts while ellipsis at the vertical center in CJK fonts. If I were writing Japanese documents, I expect it be drawn at the vertical center.

It would be great if I can use a font like this:

@font-resource {
  font-family: myfont;
  src: local(CJK-font-name);
}

@font-resource {
  font-family: myfont;
  src: local(Latin-font-name);
  unicode-range: EAW=N|Na;
}

Or to do this in opposite way:

@font-resource {
  font-family: myfont;
  src: local(Latin-font-name);
}

@font-resource {
  font-family: myfont;
  src: local(CJK-font-name);
  unicode-range: EAW=A|F|H|W, U+5C;
}

Thoughts?

[1] http://dev.w3.org/csswg/css3-fonts/#unicode-range-desc

[2] http://unicode.org/reports/tr11/



Regards,
Koji

-----Original Message-----
From: www-style-request@w3.org [mailto:www-style-request@w3.org] On Behalf Of John Daggett
Sent: Thursday, June 17, 2010 6:06 PM
To: Christoph Päper
Cc: CSS WWW Style
Subject: Re: [css3-fonts] humane 'unicode-range'


  
Christoph Päper wrote:

> Would it make sense to add keywords to ‘unicode-range’ or to add
> another font-decriptor with similar purpose to identify scripts or
> writing systems (i.e. script + language) supported by (and requested
> to be used from) the font resource? 

There was a discussion of this last year:
http://lists.w3.org/Archives/Public/www-style/2009May/0212.html


I think it boiled down to whether to use names from the Unicode
database or not and if so, how specific the names should be.  I think
the idea of named ranges for the 'unicode-range' descriptor is interesting.
I don't like the idea of additional descriptors for this (e.g. script-coverage, etc.).

It would help to have a clearer idea of the use case you imagine for this
to be able to judge whether named ranges are better than simple ranges.

One other use I can imagine is for easily dividing up large CJK fonts into defined
character ranges.

Ex: 

  unicode-range: jis-level-1, jis-level-2; /* alias for the set of codepoints in the JIS Level 1 and 2 ranges */

JIS Level 1 characters occur more commonly than JIS Level 2, etc., so
this would be a convenient way for font vendors to package fonts so that
fonts containing infrequently used characters were only downloaded in
fallback situations.
 
No matter what the set of aliases, I think we can only practically
reference ranges that are defined clearly and have a standard reference
point such as the Unicode database.

Cheers,

John Daggett

Received on Sunday, 1 May 2011 11:37:21 UTC