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Re: Relative font sizes

From: Jim Byrne <j.byrne@gcal.ac.uk>
Date: Thu, 17 Apr 2003 10:15:10 +0100
To: James Craig <work@cookiecrook.com>, <w3c-wai-ig@w3.org>
Message-ID: <BAC42F2E.1BA90%j.byrne@gcal.ac.uk>

Thanks James,

Thanks for you reply - I think we are basically in the same ball park. There
are points I could make but we could bat them back and forward for a while
to no great effect.

If you have something written on this subject and would like to publish it
on the Making Connections Unit (http://www.mcu.org.uk) please get back in
touch - your expertise would be a welcome addition to the site.

All the best,
Jim
on 4/16/03 4:44 PM, James Craig at work@cookiecrook.com wrote:

> Jim Byrne wrote:
>> There is more chance - if you are not careful - of ending up with unreadably
>> small text if a size is set in the body selector - because of the issues of
>> inheritance. For example, if you set the body to .9em - and then set the
>> paragraph selector  to .9em, and then set anchor selector to .9em - the
>> resulting link in a paragraph will be 90% of 90% of 90% of the browser
>> default size; it could get difficult trying to figure out why your links are
>> so small. 
> 
> If you don't pay attention to inheritance, then not setting the body
> size won't save you. You could still set a <p>, <strong>, and <a> to 90%
> sizes, have them all inherit from the default body size and still be
> unreadable.
> 
> This inheritance problem (and a brief solution(1)) is mentioned in the
> second half of http://css-discuss.incutio.com/?page=AvoidingHacks
> 
> Without getting into too much CSS here, you can reset nested elements'
> font-sizes back up to 1em. p a {font-size: 1em;}
> 
>> With a good understanding of all the issues this can be avoided. So it
>> depends on who is designing the page - and how aware they are of potential
>> problems; for that reason I think it is safer not to set a size in the body
>> selector.
> 
> But you have to give the users here some credit. Although they
> definately aren't all full-time developers, the mere fact that they are
> on this list means they pay more attention to web technologies than most
> (probably more than a lot of full-time developers).
> 
> Even so, I don't think ignoring the default size makes it any easier.
> The same problems still arise unless you pay attention to inheritance.
> 
>> There are problems with most units of measurement - including using keywords
>> - see http://www.alistapart.com/stories/fear4/4.html for some discussion on
>> problems with keywords. However I do agree that keywords are a good idea -
>> and if the balance of problems/virtues moved towards keywords I would be
>> happy to start using them.
> 
> That article was written several years ago and couldn't take into
> account many developments in the past few years. At that point, no Gecko
> browser was released; now there are at /least/ five (N6, N7, Mozilla,
> Phoenix, Chimera, etc.) and all of them render keyword sizes correctly.
> MacIE5, Opera, Safari/Konqueror render them correctly too, I believe.
> Windows IE5 and IE6 will render them correctly if you employ a few CSS
> comment hacks. (I think all those browsers render em and percentage
> sizes correctly, too, if implemented correctly.)
> 
> Version 4 browsers and below still have trouble with keywords, though
> more and more authors are hiding all styles from those browsers via the
> @import method. If the HTML elements are used semantically, it's still
> very readable, accessible, and usable. As someone else mentioned, see
> Netscape DevEdge in any compliant browser (previous paragraph) and then
> again in and older browser like Netscape 4, Lynx, IE3, Mosaic 1, etc.(2)
> 
> Cheers,
> James Craig
> 
> 1. The 'brief' solution mentioned is definately not a complete end-all
> fix to this problem, but it does correct the most common problem with
> font-size inheritance.
> 
> 2. Jim, I realize you are familiar with this. That last example was more
> for the other list members' benefit. I think we're pretty much in
> agreement besides that one small detail on the body size. We may have to
> agree to disagree. ;) Thanks for you response.
> 

 
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Received on Thursday, 17 April 2003 05:15:24 GMT

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