- From: Tab Atkins Jr. <jackalmage@gmail.com>
- Date: Tue, 27 Apr 2010 08:55:17 -0700
- To: Simon Fraser <smfr@me.com>
- Cc: Gregers Gram Rygg <gregersrygg@gmail.com>, Mikko Rantalainen <mikko.rantalainen@peda.net>, www-style@w3.org
On Mon, Apr 26, 2010 at 10:33 AM, Simon Fraser <smfr@me.com> wrote: > On Apr 26, 2010, at 10:16 AM, Gregers Gram Rygg wrote: > >> On Fri, Apr 23, 2010 at 12:38 PM, Mikko Rantalainen >> <mikko.rantalainen@peda.net> wrote: >>> pointer-precision: <len> | step; >>> >>> The user is expected to be able to hit targets of size <len> without >>> huge effort. The <len> should be expressed in "px", "em" or "ch" unit. >> >> That depends on how flexible this needs to be. Using a value instead >> of an input method will make this feature more complicated for browser >> developers and web developers. But I wouldn't mind, as long as there >> are some predefined keywords for different input devices. Example: >> "pointer-precision: touch", where touch could be specified to 8mm. >> >> Shouldn't <len> rather be specified in a physical unit (in, cm, mm, pt >> or pc)? A value in px might vary depending on the resolution for the >> device, and em/ch depend on the font in use. >> >> Example: >> @media screen and (pointer-precision: 10mm) { >> a { padding: 3mm; } >> ul.autocomplete li { padding: 3mm; } >> div.touchController { display: block; } >> div.nonTouchController { display: none; } >> } > > > This seems like way too much resolution. Imagine a hardware vendor tweaking the display > resolution of a device in a revision, and this causing web content to fall over a threshold > here. > > I think it's quite sufficient to simply identify the primary input method. I can imagine > the following input methods: > > pointer: mouse input (maybe include stylus?) > touch: finger-based interaction > keypad: up/down/left/right/enter navigation only Agreed. I don't think I'd ever vary my display enough to need an actual length value there. As far as we know, there are only two precisions, that of a mouse/stylus and that of a finger. As well, a length-based variable ignores alternate input methods that could be usefully handled, like keyboard navigation, as Simon points out. I could see offering a slightly different presentation to keyboard users, such as show/hiding useful anchors. ~TJ
Received on Tuesday, 27 April 2010 15:56:10 UTC