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

From: Christoph Päper <christoph.paeper@crissov.de>
Date: Mon, 7 Apr 2008 22:45:37 +0200
Message-Id: <31D3A05C-D64C-434E-AC07-EB32835CC13A@crissov.de>
To: CSS Style <www-style@w3.org>

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


I think it's obvious that the intention was to have the query refer  
to device pixels.

I might make sense to call device pixels 'dots' in CSS context, which  
is what the 'd' is representing here. Anyhow, I believe the unit  
abbreviated by 'dpcm' here is virtually unused elsewhere. When asked  
for the device resolution in metric measures, one usually gives the  
diameter or width (equals height in many cases) of one dot measured  
in micrometres (µm) or millimetres (mm). I would much prefer this  
reciprocal method in the spec, although I admit that 'dpi' is seen  
more frequently. It doesn't need a new type of units, because any  
absolute length unit could be used, but 'um', the ASCII-compatible  
representation of 'µm', would be a nice addition.
Received on Monday, 7 April 2008 20:46:12 GMT

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