RE: [css3-fonts] opentype font feature support

Wednesday, March 10, 2010 6:30 AM <jdaggett@mozilla.com>:

>I think 'none | normal' makes a lot of sense, assuming 'normal'
>implies "apply metric kerning if data available in the font".

This seems all that's necessary - on or off. If there's kerning data in the font and the UA supports the property, it should be applied as "normal".

Regards,

rich

-----Original Message-----
From: www-style-request@w3.org [mailto:www-style-request@w3.org] On Behalf Of John Daggett
Sent: Wednesday, March 10, 2010 6:30 AM
To: Jonathan Kew
Cc: www-style list
Subject: Re: [css3-fonts] opentype font feature support


Jonathan Kew wrote:

> However, I agree that "normal" really ought to mean using the
> kerning data in the font. (And could be renamed "kern" if people
> want it to be more explicit.) Then "none" or "no-kerning" is
> obviously used to turn it off.
>
> I'm not at all sure I'm in favor of a setting that means "user agent
> to decide".... it seems to me that if a UA is capable of kerning at
> all, then it should be doing it by default as a standard part of
> text rendering (just like it should be doing other standard features
> such as ccmp, locl, etc.) 
> 
> So, I think the essentials would be
> 
>     font-kerning: none | normal
> or
>     font-kerning: no-kern | kern

Thinking about this a little more now, I think 'none | normal' makes a
lot of sense, assuming 'normal' implies "apply metric kerning if data
available in the font".  If a user agent is supporting things like
variant glyphs then it's already doing enough processing that
performing metric kerning is unlikely to have a significant impact on
performance.

I think optical kerning should be left out for now, if it's really
desirable a separate value can be added later.

John

Received on Wednesday, 10 March 2010 23:42:40 UTC