- From: Bert Bos <bert@w3.org>
- Date: Wed, 31 Jul 2013 12:18:38 +0200
- To: www-style@w3.org
On Tuesday 30 July 2013 22:34:45 fantasai wrote:
> On 05/10/2013 07:17 PM, fantasai wrote:
> > Our proposal...
>
> Steve Zilles asked for proposed text for these...
>
> > Part I: letter-spacing: <length> allows justification
> >
> > This solves backwards-compatibility with such style sheets as
> > you mention, and is also consistent with implementations.
> >
> > It is also consistent with how 'word-spacing' behaves: <length>
> > values there allow justification.
> >
> > (Note: This would be a change from CSS2.1, so will need to be
> > backported.)
>
> Proposed text, added to 'letter-spacing' section;
>
> | Depending on the justification rules in effect, user agents may
> | further increase or decrease the space between characters
> | in order to justify text. See 'text-justify' for details.
> >
> > Part II: Add 'fixed' keyword to disallow justification
> >
> > We have a problem if we allow justification for letter-spacing
> > always; German typesetting rules requires that it not be
> > allowed! So here is a proposal --
> >
> > letter-spacing: normal | <length> || fixed
> >
> > If 'fixed' keyword is specified, then justification cannot alter
> > letter-spacing, only word-spacing.
> >
> > I think Part I is important to take. I am open to other suggestions
> > to solve the use case in Part II...
>
> Proposed text:
> | fixed
> |
> | When this keyword is specified, user agents must not adjust
> | spacing between characters in order to justify text.
> | Justification is only allowed at expansion opportunities
> | provided by a single character (such as a word separator or
> | other punctuation).
> |
> | Unless the ''fixed'' keyword is specified, depending on ...
> | [above] ...
That changes the meaning of 'letter-spacing' as it has been used until
now (and which I've been relying on).
Besides, using inter-letter spacing for justification is something you
don't want to happen by default. If you have a really difficult text,
you may want to explicitly enable it, if there is no other option.
I propose explaining under the <length> value of 'letter-spacing' that
the space between letters may still be varied for the purposes of
justification if 'text-justify' is set to 'distribute':
User agents may not further increase or decrease the inter-character
space in order to justify text <ins>except if 'text-justify' is
'distribute'</ins>.
>
> Relatedly, I think we need to add this to the 'text-justify' section:
> | It is not defined in this level whether or how other factors
> | (such as font size, letter-spacing, glyph shape, position
> | within the line, etc.) may influence the distribution of
> | space to expansion opportunities within the line.
>
> because while justification space is additive with tracking, I don't
> think we want to define that it can't account for differences in
> tracking: I'm pretty sure that adding 2px space between characters
> is more noticeable with zero spacing than with 10px spacing, and
> while we do want differences in letter-spacing to not be equalized
> away, imo the UA should be allowed to bias justification space to
> make it less noticeable.
>
> ~fantasai
Bert
--
Bert Bos ( W 3 C ) http://www.w3.org/
http://www.w3.org/people/bos W3C/ERCIM
bert@w3.org 2004 Rt des Lucioles / BP 93
+33 (0)4 92 38 76 92 06902 Sophia Antipolis Cedex, France
Received on Wednesday, 31 July 2013 10:19:07 UTC