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Re: cross posted form IG

From: Matt May <mcmay@bestkungfu.com>
Date: Sun, 6 May 2001 09:37:06 -0700
Message-ID: <002c01c0d64a$d957ae60$6601a8c0@sttln1.wa.home.com>
To: "W3c-Wai-Gl" <w3c-wai-gl@w3.org>
I can try to answer this one...

First, px _is_ absolute. It's font height in number of pixels.

The major issue is that pixel-sized fonts can't be resized using the font
tools in the browser. So if I have my browser's font set to "Largest", and
you have your fonts set to "8px", what I'll see is 8px no matter how I try
to resize. A user's only theoretical way around this would be to use a
client-side style sheet, which is still unsupported in most browsers; to
disable style sheets, which could cause an entire page to unravel; or to use
a screen magnifier.

There are some other minor issues with px, like it's not aware of the size
or resolution of the display. Monitors are considered to be 72 pixels per
inch universally, but at higher resolutions, the effective ppi increases
(displays on graphics workstations, or smaller devices at high-res, like a
subnotebook or an iPaq handheld, can be over 100-110ppi). This will be a
more obvious accessi-usability issue in a couple years when 200ppi displays
make it to market, and _none_ of us will be able to see 8px text without
accessible technologies. :)


----- Original Message -----
From: "Robert Neff" <rneff@bbnow.net>
To: "W3c-Wai-Gl" <w3c-wai-gl@w3.org>
Sent: Sunday, May 06, 2001 6:02 AM
Subject: cross posted form IG

> am generating a web site and prefer the device-dependent sizes and for the
> fonts and margins using 'px'.  as this changes with the screen, i like
> however, the WCAG and Bobby recommend 'em' and percentages.  For example,
> form WCAG, "Only use absolute length units when the physical
> of the output medium are known, such as bitmap images."
> As 'px' is device-dependent, it is not absolute nor realtive.  Therefore,
> there an issue to use 'PX' fonts sizes and margins in Stylesheets?
> thanks
Received on Sunday, 6 May 2001 12:39:27 UTC

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