

Pixels - blakefrost
http://blakefrost.tumblr.com/post/10612682218/pixels

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narkee
If 1 pt = 0.75 pixels, then there is no meaningful distinction between the
measurements. It's a scale factor. It's like advocating for mm over cm. I
don't quite understand the point of the article.

If he's worried about terminology, then redefine the word pixel as being 4/3
of a pt. Problem solved.

Also, either his last sentence is a mistake, or I must have misunderstood the
entire article.

~~~
georgemcbay
I totally agree.

As someone who is a programmer, not a designer my reaction to reading this is:

"What is this I don't even...."

I figured he was going to be advocating moving to a relative system where the
rendering engine was made aware of the dpi of the display and vector graphics
(or differently sized bitmaps as in the Android ldpi/mdpi/hdpi model) were
used where possible, because we very clearly have to start embracing that
model as the dpi and size of devices is beginning to be wildly divergent in
all directions... but what he's actually suggesting is basically meaningless,
IMO.

~~~
blakefrost
If you're referring to that last line, yeah I totally fat fingered that. I
fixed it.

I'm advocating moving to an absolute system. As in an absolute width, measured
here, measured there, measured anywhere. This can then be scaled to mimic the
appropriate absolute width based on viewing distance and other parameters such
as screen real estate.

I know what you're thinking. "But pixels are an absolute measure...". Actually
yes, and actually yes. Pixels are an absolute measure in the sense that they
state that I want something to be the absolute size of a single pixel but the
pixel is arbitrary and now your absolute measure is relative to the actual
size of the pixel. As mighty as this sounds, it actually turns out to be not
all that useful in design; as screen resolutions vary so will your renderings.
This is why CSS pixels are different, they're for all intents an purposes
interpreted as 1/96th of an inch. So, great they're absolutely 1/96th of an
inch, they're absolute! So why should you stop using them? This paragraph is
why you should stop using them. I didn't like writing this paragraph, and I'm
gonna guess you didn't like reading it. Pixels are confusing and pixels are
______* liars. Use points.

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mikeklaas
I'm pretty sure that this is wrong. A css pixel is a screen pixel as long as
the screen dpi is reasonably close to 96dpi. Certainly 1px borders on my MBA
are always 1px, not a blurry px and a half.

The correspondence between pixels and screen pixels break down when the dpi is
nuts, which is why 1 px (css) = 2px (screen) on the retina screen of the
iPhone 4.

You can't avoid pixels in CSS. Yet.

~~~
ender7
You are correct. This article is misleading on many levels.

A CSS pixel is ALWAYS the exact same thing as a screen pixel, unless:

1\. The browser's view has been "zoomed". This can occur on desktop browsers
or mobile browsers, although it's much more common on mobile browsers.

2\. You are on a quad-pixel display like an iPhone 4. In this case, 1 CSS
pixel = 4 real pixels, exactly.

Options 1 and 2 rarely breaks anything due to a use of "px". Those situations
that are problematic usually are due to a design flaw in your CSS (and will
not be fixed by switching to "pt").

Option 2 will never break your CSS. The only time it matters is if you want to
serve double-resolution images [1]. Other than that, you have no access to the
super-grid, so don't worry.

[1] [http://www.sitepoint.com/razor-sharp-images-in-mobile-
safari...](http://www.sitepoint.com/razor-sharp-images-in-mobile-safari-on-
iphone-4/)

~~~
blakefrost
"A CSS pixel is ALWAYS the exact same thing as a screen pixel"

Not true. You should reread the article, if you care to, and perhaps check the
sources. Even if what you were saying was true do you think it makes sense to
define things at the native resolution of a monitor? :Faceplam:

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mwsherman
The idea is that someday browsers will be resolution-independent. They’ll have
to let go of 96ppi and probably pixels altogether. Making this change is
preparing for a future that may or may not come to be. (The Retina Display
hints at this.)

The point is valid if not immediately useful. Practically speaking, if you can
start and stay with pt measurements, you might as well.

(Regarding how we might bring in a resolution-independent future browser, it
would have to be some sort of meta tag or doctype, or maybe CSS fallbacks as
we do with font faces.)

~~~
blakefrost
This has actually already happened. Just start using resolution independent
measures and never look back. I'm telling you, they work.

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akavlie
Pixels are the best way to get consistent cross-browser font sizes:
<http://css-tricks.com/2580-css-font-size/>

Also, graphics are inherently bound to a fixed pixel size... so layouts often
have to follow, if you don't want things getting out of whack at other pixel
densities.

~~~
blakefrost
You would think so, but that's not true. Design in points (1/72) and ship in
points. I'm telling you, you're stuff is rendering at 1/96th, not native res.
Try it out for yourself. Make two divs, specify one as 96px and the other as
72pt. See, same size, same size. Now think, if that were an image... Not
native res, but yet it still looks right... Interesting.

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orta
perhaps if he'd offered to go with em's and to just roll with keeping the
design of a page relative to the font size I could understand.

But the easiest way to understand why everyone still uses px, is because when
you've got a design created beforehand it'd take an awful lot of work to make
it exact using relative sizes.

~~~
blakefrost
Points aren't relative, their absolute. em is great but another subject
entirely.

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maletor
that website is loaded with pixels in the css

~~~
blakefrost
Do what I say, not what I do. j/k. That's a tumblr theme, I didn't write it
and I take no responsibility for it.

