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[css3-mediaqueries] Is 'resolution' in terms of device pixels or CSS pixels?

From: L. David Baron <dbaron@dbaron.org>
Date: Sun, 6 Apr 2008 21:00:08 -0700
To: www-style@w3.org
Message-ID: <20080407040008.GA17448@ridley.dbaron.org>

The 'resolution' media feature has two new units, 'dpi' and 'dpcm'.
Are these "dots" supposed to be device pixels or CSS pixels?

(I'm not sure what the use cases for this feature are.  One that I
could come up with is switching which images to serve (to save
bandwidth) for images whose sizes are specified in physical units.
For this use case device pixels would be better.  However, I'm not
sure what other use cases people have.)

http://www.w3.org/TR/2007/CR-css3-mediaqueries-20070606/#units is
clear that 'px' always mean CSS pixels, but I don't see anywhere
that defines 'dpi' and 'dpcm'.  (I'd lean towards saying the current
spec suggests that it's device pixels, but I don't think it's


L. David Baron                                 http://dbaron.org/
Mozilla Corporation                       http://www.mozilla.com/
Received on Monday, 7 April 2008 04:01:13 UTC

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