[whatwg] Features for responsive Web design

[Tab Atkins Jr.]

On Tue, May 15, 2012 at 9:28 AM, Ian Hickson <ian at hixie.ch> wrote:
> On Thu, 10 May 2012, Tab Atkins Jr. wrote:
>>
>> That all said, I don't like the "2x" notation.  It's declaring "this
>> image's resolution is twice that of a normal image".  This has two
>> problems.  For one, we already have a unit that means that - the dppx
>> unit.  Using "2dppx" is identical to the meaning of "2x".  Since
>> image-set() is newer than the dppx unit, we should change it to use
>> <resolution> instead.
>
> dppx is pretty ugly. I agree with hober's "2x" design.
>
>> For two, I'm not sure that it's particularly obvious that when you say
>> "2x", you should make sure your image was saved as 196dpi.  You have
>> to already know what the default resolution is.
>
> You don't have to. The resolution of the image is ignored.

If you don't set your image's resolution appropriately, you'll get
unexpected sizing effects.

>> As well, I think that values like 300dpi are pretty common, and they
>> don't map to integral 'x' values.  If people say "screw it" and use
>> "3x", this'll be slightly wrong and I think will cause ugly blurring.
>> If we make this take <resolution>, people can just use the dpi unit.
>
> 3.125x isn't particularly difficult to specify.

I actually didn't even realize that 300dpi is 3.125 times 96dpi.

Regardless, I think being able to specify "300dpi" is easier than
using a calculator.

~TJ