Re: [css21][css3][svg] SVG and unit-less length values

On 8/14/10 10:54 PM, Robert O'Callahan wrote:
> On Sun, Aug 15, 2010 at 9:18 AM, Charles Pritchard <chuck@jumis.com 
> <mailto:chuck@jumis.com>> wrote:
>
>     Working with 2x pixel ratio displays will create more demand for
>     improvements to the current state of CSS.
>     Though pixel ratio does turn the CSS pixel into a relative unit,
>     there are some difficulties in specifying quality.
>
>     One can not, for instance, set the pixel ratio of individual elements.
>
>
> It doesn't matter for most elements.
>
>     I've found that my canvas tags need additional styling:
>     <canvas width="960" height="640" style="width: 480px; height: 320px;">
>
>
> As specced, browsers are allowed to use a higher-resolution backing 
> store for the canvas element if they want to. But there are some 
> compatibility problems around the getImageData/putImageData APIs. 
> Anyway, the issues around canvas are specific to canvas.
Consistency throughout HTML APIs will help everyone; I realize it's a 
"canvas" issue;
I suspect attention to the issue will have other benefits outside of 
canvas, in the long run.

>
>     Many authors have noticed that they need high-res and low res
>     stylesheets and supporting images. Some have gone so far as to
>     suggest @2 be suffixed
>     onto image names.
>
>
> To address this, we just need Webkit's device-pixel-ratio media query 
> to be standardized.
min-device-pixel-ratio will certainly see more use, as will 
window.devicePixelRatio
and I'm sure they'll be standardized.

....

As the topic of this thread is both about SVG units and about SVG CSS 
convergence:

Many browsers have a zoom option, (CTRL SHIFT +, and alike),
it'd be nice to see more CSS support for that situation.

I've recently been using a monitor from 6 feet away for watching TV,
I now use CTRL + far more often. Apart from being eccentric, it's a good
way to see how viewport scaling is currently supported by UAs and authors.