Re: Baselines (was RE: Units, font sizing, and zoom suggestion for CSS 3)

Bert Bos wrote:
> 
> Erik van der Poel writes:
> > 
> > It's nice that you give an example using the Q element and the LANG
> > attribute, but I think we need to keep in mind that real world documents
> > often mix ASCII and Japanese characters, without the use of Q and LANG.
> > We need a baseline story for this too.
> 
> That's probably true, although not recommended... Does Mozilla include
> a spell checker? If so, that could be an incentive for people to
> properly mark-up the different languages in a document.

We do have a spell checker, but I wonder if humans will really bother to
indicate the language of short pieces of text embedded inside documents
in a different language. The spell checker may complain about the
spelling of those short pieces of text, but will the user then indicate
the language? Besides, the text might not be in *any* language. It might
be a technical string, such as an identifier in C++, or something.

> 1) One idea I've heard to deal with this is selectors for scripts (or
> alternatively for Unicode ranges). Most recently from Matthew
> Brealey[1].
> 
>     :chars(U+4E00-4E1F) { baseline-identifier: ideographic }
> 
> 2) Somewhat simpler is to introduce script-specific properties:
> 
>    P { baseline-identifier-ideographic: ideographic;
>        baseline-identifier-latin: lower }
> 
> 3) But this all has the smell of defining the obvious. Maybe the
> simplest solution is to add 'auto' to 'baseline-identifier'.

I like your (3) most, if we introduce baseline-identifier at all.

> I've heard different explanations of the ideographic baseline. CSS2
> indeed calls it the "central baseline"[2] so I guess we should stick
> to that.

But CSS2 and the QuickDraw GX book are the *only* places I've seen, that
talk about a central baseline for East Asian text. Lunde's book,
Windows's MS Gothic and X Windows's JIS fonts all have a baseline that
cuts through a very low part of the glyphs. And QuickDraw GX basically
failed. So, the CSS2 spec ends up confusing people like me.

> > That sounds similar to the min-line-height and line-height-override
> > stuff that we've been discussing at mozilla-layout@mozilla.org.
> 
> Any pointer?

news://news.mozilla.org/38833F8D.94004F13%40escape.com
news://news.mozilla.org/388508DD.D2ED8883%40netscape.com

Erik

Received on Thursday, 3 February 2000 18:01:02 UTC