On Tue, Sep 10, 2013 at 12:45 PM, Dean Jackson <d...@apple.com> wrote:
> > On 11 Sep 2013, at 5:32 am, Ian Hickson <i...@hixie.ch> wrote: > > > On Wed, 11 Sep 2013, Dean Jackson wrote: > >> On 11 Sep 2013, at 12:14 am, Stephen White <senorbla...@chromium.org> > >> wrote: > >>> > >>> now that some browsers are including browser zoom (page zoom) in > >>> window.devicePixelRatio > >> > >> Ouch. Who is doing this and why? > > > > Why ouch? > > Because we’ve always operated under the assumption that devicePixelRatio > is the mapping from CSS px to device pixels at 1:1 scale/zoom, and that it > is constant for a particular display. The only change content would see is > if the window is dragged to/from a high resolution screen. > > There are other ways to query the page zoom. > > I fear this will break existing content. I don’t think we’d ever want to > change the behaviour. There's a thread on www-style: http://lists.w3.org/Archives/Public/www-style/2012Nov/0144.html It's been in firefox for a while and blink is going to ship it soon: https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/RyUSi3zdumQ > > > > > > Actually what I really think we should do is also change the > > window.devicePixelRatio for pinch zoom. Combined with the suggestions for > > canvas, that would allow (as Rik pointed out on IRC) for high-quality > > canvas all the way zoomed in, and for cheap canvases when zoomed out > I believe pinch zoom should not change devicePixelRatio. It would be nice if there was a standard way to determine pinch zoom though and if the canvas could automatically resize.