Re: [css3-fonts] font-specific feature handling

Tab Atkins Jr. wrote:

>> The concern about the wrong contextual alternates being applied to the
>> next font down the line in the font stack is about a concern that the
>> *wrong* information would or could be delivered if extra controls
>> aren't enforced.
>
> Indeed, we don't want the wrong information to appear.  Thus our
> concern, and our attempt to create solutions where it is impossible
> for it to happen accidentally, especially in cases that are *very*
> unlikely to receive testing coverage from authors.

The original discussion was centered around font-variant-alternates
values which take a numeric-value like stylistic sets (e.g.
'font-variant: styleset(1,3)'), not contextual alternates which do not
(e.g. 'font-variant: contextual').

In general, fallback to special-case variant forms is *not* going to
communicate the "wrong information" it's simply going to display a
modified form of the glyph that would have been displayed in the default
case.

In the examples I posted [1], there are some cases where the values used
are consistent across a set of fonts, and other cases where they are
not.  There are also cases where fonts with specialized discretionary
ligatures or contextual alternates can be very font specific.

Restricting the use of certain values would not make it impossible for
visual discordance to occur in font fallback situations because that's
already the nature of font fallback, a different font is being used than the
one the author ideally desires.  If you order a gin-and-tonic and
someone brings you a mojito, whether a lemon twist is included is of
less importance.

Cheers,

John

[1] http://people.mozilla.org/~jdaggett/images/fallbackexamples.png

Received on Monday, 22 March 2010 02:22:52 UTC