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NNTP-Posting-Date: Thu, 28 Jun 2012 13:30:19 -0500
Date: Thu, 28 Jun 2012 11:30:19 -0700
From: fantasai <fantasai.li...@inkedblade.net>
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Subject: Re: Printing in 600 dpi
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On 06/28/2012 07:10 AM, Ben Bucksch wrote:
> Thanks fantasai :-), for the answer.
>
> On 28.06.2012 08:16, fantasai wrote:
>> so for a 600px image you want printed at 600dpi, size your image as 1in, rather than as 600px, and it should print properly.
>
> Well, it's not as simple as one image, it's a Javascript library that generates the output. The JS lib must get "4920px" as
> width from DOM/style APIs, and that must print as 21cm width in 600 dpi. That would solve it, and I *should* be able to set
> this via CSS rules.
>
>> In CSS, the ratio of px to cm is fixed
>
> Well, that's the problem, then. It's inherently wrong.

Yes, we realize that. Unfortunately, the correct behavior (which is described in
older revisions of CSS2.1) turned out to not be Web-compatible: the Web assumes
everyone is running 96dpi and that therefore 'width: 1in' is equal to 'width: 96px'.
And so after a lot of debate (hundreds of messages worth), the CSSWG resolved
on the text here:
   http://www.w3.org/TR/CSS21/syndata.html#x39

You can see the changes here:
   http://fantasai.inkedblade.net/style/specs/css2.1/px-unit

~fantasai