Stylesheets - HTML, CSS

Author

HTML, CSS

MaxNeo

2004-08-30, 12:16 pm

Hi everybody,

I have a question, hope somebody will help me out!

You can try here with this site, View, Lettersize bigger and it'll be changed.
But some of the sites that I've visited, whatever you do, it won't change!

How can they manage to do that?

Thank you,
MaxNeo

David Dorward

2004-08-30, 12:16 pm

MaxNeo wrote:

> You can try here with this site,

What site? Google groups? Most people do not use a web interface to access
usenet.

> View, Lettersize bigger and it'll be changed. But some of the sites that
> I've visited, whatever you do, it won't change!

There is a bug in Internet Explorer which makes font resizing very difficult
when the font size is specified in absolute units (like pixels). You should
avoid using absolute units for font sizes and stick to those relative to
the user's preferences (using % for instance).

--
David Dorward <http://blog.dorward.me.uk/> <http://dorward.me.uk/>
Home is where the ~/.bashrc is

Alan J. Flavell

2004-08-30, 7:17 pm

On Mon, 30 Aug 2004, David Dorward wrote:

> There is a bug in Internet Explorer which makes font resizing very
> difficult when the font size is specified in absolute units

That's part of the design! The whole point (no pun intended) of
absolute units is that they are specified to be absolute units,
verifiable by reference to some scratches on a metal bar in Paris -
or whatever the modern equivalent is.

(The fact is that they aren't "absolute" in practice, because screens
usually aren't calibrated to a standard measure; but that's a bug in
the implementation, not in the specification).

It's not as if the CSS specification doesn't address this problem
already:

http://www.w3.org/TR/REC-CSS2/syndata.html#length-units

Absolute length units are only useful when the physical properties of
the output medium are known.

In short: "unfit for screen display situations". The only way to deal
with such inappropriate specifications is to override them. One
really should -not- expect to be able to re-scale them - that would be
defeating their purpose, i.e introducing a bug in order to compensate
for bad design. But CSS is meant to be optional, so there's nothing
wrong with overriding the inappropriate specification entirely,
IMNSHO.

> (like pixels).

Ah: CSS pixel units are a category of their own; they don't officially
fall under "absolute length units", they're supposed to be adjusted to
the display situation (device resolution and expected viewing
distance). In practice, of course, it's a different story...

But in theory, CSS px units (properly scaled according to the
principles in the CSS spec) would be an appropriate choice for a mass
viewing situation, e.g for a projection screen, where individual
choice of font size according to each reader's wishes or needs is not
feasible.

> You should avoid using absolute units for font sizes and stick to
> those relative to the user's preferences (using % for instance).

Of course - no disagreement about the conclusion!

Chris Morris

2004-08-31, 7:16 am

"Alan J. Flavell" <flavell@ph.gla.ac.uk> writes:
> But in theory, CSS px units (properly scaled according to the
> principles in the CSS spec) would be an appropriate choice for a mass
> viewing situation, e.g for a projection screen, where individual
> choice of font size according to each reader's wishes or needs is not
> feasible.

Projection screens vary in quality a lot, though. Most of the time
when I'm demonstrating things on projectors I can keep the font-sizes
at browser-default and the people at the back have no trouble
reading. Once I had to move it to ~150% of normal just to get the text
(which on the slides I was using was already quite large) to be
readable at the front. That's not really something that the scaling
principles in the text would cover - the text was the same physical
size, the audience about the same distance away (which of course might
not be the case, but that does allow some sizing by seat position...),
but the screen/projector quality varied so much.

--
Chris

Alan J. Flavell

2004-08-31, 7:17 pm

On Tue, 31 Aug 2004, Chris Morris wrote:

> "Alan J. Flavell" <flavell@ph.gla.ac.uk> writes:
>
[color=darkred]
> Projection screens vary in quality a lot, though.

Sure! How does that saying go again? - "In theory, theory and
practice are the same; but in practice ...".

I'm not sure that I can think of a situation where the ability to
adjust the presentation according to the needs of the user(s) isn't a
benefit. A benefit directly to the users - but also indirectly to the
deezyners, if only they could recognize it.

all the best