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Re: Sizing

From: Axel Dahmen <brille1@hotmail.com>
Date: Sun, 17 Sep 2006 16:34:28 +0200
To: www-style@w3.org
Message-ID: <eejmfb$aq3$1@sea.gmane.org>

"David Woolley" <david@djwhome.demon.co.uk> schrieb im Newsbeitrag
> > What is rendered on screen always varies depending on the screen
> > Units like "pt" are never displayed in their correct sizes. Similar for
> That's a platform problem, and may not even be a browser problem.  Only
> if the platform knows the display size can it correctly calculate this
> providing correct display size information is generally beyond the
> of the average Windows user.
> In the case of projection devices, the problem may be particularly
> difficult.

You're right. I must admit that I don't have a too clear picture of what is
required yet...

Here's an example of what I'm up to:

a)  A HTML page looks completely different on my 1600*1200 screen than on an
A4 page or a 1024*768 screen. This makes it impossible to show a document to
be printed the way it will be printed. There should be an option to scale
down a document dynamically, e.g. to viewport width.

b)  It's impossible to scale images down. In CSS you can't define that
(dynamically loaded) images should display in 50 % of their intrinsic size
(which is pixels).

b)  Currently browsers use their intrinsic scaling to keep image/text size
relation consistent between screen/printer. Instead of using their own magic
they could inject a calculated value, taken from screen dimensions/graphics
resolution or printer resolution, using CSS.

The typical menu items used to shrink or grow display could use CSS to add
scaling to the <body> element.

DHTML could be able to read and interpret this value. CSS is for display
formatting, so why not also provide a global scaling?

> Designing in pixel sizes is generally a bad idea for a language like
> HTML which is intended to be usable on an extremely wide range of devices,
> details of which are not known to the author.

Design isn't always static. Particularly if you load images dynamically from
a database you need to take them as they are. Instead of adding a style for
each and every image providing a style attribute to the image, calculating
pixel in point (which I did and that's why I'm suggesting this), I believe
there should be a general scaling property.

> The author doesn't have access to this information.  But in any case
> 72pt = 2.54cm by definition, so pt:px and cm:px cannot be defined
> independently.

The author doesn't, but the browser has. This rule length option should be
used only by browsers to inject proper default scaling to images. I don't
get you last sentence. Why should they be defined independently? A rule like
"300px" replaces "500cm", AFAIK.

Best regards,
Axel Dahmen
Received on Sunday, 17 September 2006 14:36:16 UTC

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