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Re: [css3-values] Physical length units (was: [css3-mediaqueries] DPI in resolution media queries)

From: Matthew Wilcox <elvendil@gmail.com>
Date: Sun, 19 Feb 2012 14:30:42 +0000
Message-ID: <CAMCRKiK0L0EfPx3nBwRP23Yen+ThrbEdOPR3-EVVpCF=y+gRbA@mail.gmail.com>
To: robert@ocallahan.org
Cc: Lea Verou <leaverou@gmail.com>, Boris Zbarsky <bzbarsky@mit.edu>, www-style@w3.org
I think we often forget who our audience is.

The fact that cm etc don't result in those units is what is super
confusing. Why in the world would any author expect 1cm to *not* be
1cm, and know to use 1trucm instead? If the vendor-prefix 'thing' has
taught us anything it is that the vast majority of authors do not read
specs - those people go on gut reaction and logical extrapolation.

CSS units are broken, a deep understanding of technical considerations
should not be required in order to achieve a 1cm line when you've
specified a line to be 1cm.

Please can we re-focus on sane semantics and remember that the
internal implementation difficulties are our problem to fix? "Don't
use that meter ruler, use the bigger one instead" is not sane. Sane
behaviour is vitally important, not just getting features through


On 19 February 2012 09:46, Robert O'Callahan <robert@ocallahan.org> wrote:
> On Thu, Feb 16, 2012 at 7:31 AM, Lea Verou <leaverou@gmail.com> wrote:
>> Yes! That would totally solve it. Although `truemm` is a but unwieldy.
>> Some kind of switch that modifies how `mm`,`cm` and `in` behave would be
>> better IMO.
> That would be super confusing IMHO. A new unit is easier.
>> Potential issue: non-square pixels (quite common in LCD screens that are
>> not at their native resolution).
> Handling that "properly" would be a real nightmare. Just define it to be the
> geometric mean of the two axes, and people who are running LCD screens in
> strange resolutions don't get great results.
> Rob
> --
> “You have heard that it was said, ‘Love your neighbor and hate your enemy.’
> But I tell you, love your enemies and pray for those who persecute you, that
> you may be children of your Father in heaven. ... If you love those who love
> you, what reward will you get? Are not even the tax collectors doing that?
> And if you greet only your own people, what are you doing more than others?"
> [Matthew 5:43-47]
Received on Sunday, 19 February 2012 14:31:10 UTC

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