- From: Alan Gresley <alan@css-class.com>
- Date: Thu, 11 Nov 2010 15:44:46 +1100
- To: "Tab Atkins Jr." <jackalmage@gmail.com>
- CC: Brad Kemper <brad.kemper@gmail.com>, Markus Ernst <derernst@gmx.ch>, "www-style@w3.org" <www-style@w3.org>, "lee.kowalkowski@googlemail.com" <lee.kowalkowski@googlemail.com>
Tab Atkins Jr. wrote: > On Wed, Nov 10, 2010 at 3:23 PM, Brad Kemper <brad.kemper@gmail.com> wrote: >> On Nov 10, 2010, at 8:35 AM, "Markus Ernst" <derernst@gmx.ch> wrote: >> >>> Besides the discussion on image spriting being an appropriate use case or >>> not, I think that Lee's actual request is actually not silly. I share his >>> point that it would be consistent to have the possibility to set background >>> position values separately, but I would consider background-position-top, >>> -right, -bottom, and -left properties more appropriate than -x and -y >>> properties, just as for element position, border and whatever. >> I don't know how that would work if there were 4 component lengths in a >> single declaration. Seems a little more complicated. > > Presumably it would be similar to how top/right/bottom/left work right > now - if both -left and -right are specified, the position is > overspecified, and -right is ignored. > > ~TJ That does not sound correct. An over-specified case sounds much like something over-constrained. Also it shows the initial error in mapping background-image to x and y axises. Why do left or top always win? I can write. margin-top: 10px; margin-right: 10px; margin-bottom: 10px; margin-left: 10px; None of these are ignored so if I write. background-position-top: 10px; background-position-right: 10px; background-position-bottom: 10px; background-position-left: 10px; I would expect the same as it I simply wrote. background-position: 10px 10px 10px 10px; This would work logically with padding, border-width and margin. padding: 10px 10px 10px 10px; border-width: 10px 10px 10px 10px; margin: 10px 10px 10px 10px; There is no ambiguity in what edge I am referring too. Giving background-position to all four edges would give the image an implicit width. So it would behave in the same manner as absolute positioning. I covered some of this here [1] and here [2]. The examples which I linked to are now reloaded [3] and [4]. The former is for fixed width boxes and the later is for fluid width boxes. The current background-position options are in black. My proposed background-position options from 2007-2008 are in blue. I do not know the status of calc() but this was use as an argument against my proposal. 1. <http://lists.w3.org/Archives/Public/www-style/2007Nov/0255.html> 2. <http://lists.w3.org/Archives/Public/www-style/2008Jan/0425.html> 3. <http://css-class.com/test/temp/level2/background-position-and-size1.htm> 4. <http://css-class.com/test/temp/level2/background-position-and-size2.htm> -- Alan http://css-class.com/ Armies Cannot Stop An Idea Whose Time Has Come. - Victor Hugo
Received on Thursday, 11 November 2010 04:45:21 UTC