On Tue, Nov 13, 2012 at 5:21 PM, Tab Atkins Jr. <jackalmage@gmail.com>wrote: > On Tue, Nov 13, 2012 at 2:40 PM, Robert O'Callahan <robert@ocallahan.org> > wrote: > > On Tue, Nov 13, 2012 at 11:47 AM, Tab Atkins Jr. <jackalmage@gmail.com> > > wrote: > >> Like others, I feel strongly that *that* kind of zoom should affect > >> dPR and d-p-r. (Perhaps we should call it "rescale", to separate it > >> from the related-only-thematically "zoom" operation that mobile > >> devices do?) > >> > >> I suspect that Simon's statements are about "zoom", not "rescale", and > >> that he (and Apple in general) are fine with rescaling affecting dPR. > >> > >> In any case, it appears that FF and IE both change dPR when you > >> "rescale", so that's the behavior we should go with. > > > > Great. Can you check that Chrome does the right thing? We don't want > compat > > problems to arise here, and we've already seen some pages that are making > > some questionable assumptions. > > As far as I can tell, we do the wrong thing. When I Ctrl-+ my way to > maximum "zoom" (really "rescale", I think) on my desktop (such that > <body> reports its width as being 272px wide instead of 1424px), > window.dPR still returns 1. > > That's a completely different type of 'zoom' from what happens on mobile. Ctrl+ in Chrome is 'Page Zoom' using the terminology here: http://trac.webkit.org/wiki/ScalesAndZooms. Pinch zooming on a mobile device in WebKit is 'Page Scale' using that terminology. Neither change window.devicePixelRatio - that's an artifact of the display and cannot be changed by user interaction. - James > ~TJ > >
Received on Wednesday, 14 November 2012 02:02:36 UTC