- From: Ben Ward <benmward@gmail.com>
- Date: Sat, 9 Apr 2005 15:57:30 +0100
- To: Anne van Kesteren <fora@annevankesteren.nl>
- Cc: W3C CSS List <www-style@w3.org>
All seems pretty sound Anne - as ever. One small note regarding your comments on the 'background-size' property. Although as you point out, it may not be desirable for authors to stretch out bitmap images, would the propery not prove useful when using a vector based image format, which would surely scale smoothly by design? Oh and my understanding of repeat-[up|down|left|right] is that you could position the background to originate at (say) 50% on the x axis, and repeat-left back to the origin (but not repeating onto the right hand side of the element). Presumably an enhancement on blanket horizonal or vertical repeating. For the WG: If repeat-left|etc. were used, would they be usable in combination? (So as to specify repeat-up and repeat-left, for example). On Apr 9, 2005 1:08 PM, Anne van Kesteren <fora@annevankesteren.nl> wrote: > > I think the specification should have a section that clarifies the terms > SHOULD, MUST, etc. The rest of the comments I gave per section. I might > have missed a few bits, I'll reread the draft when it becomes last call. > > * 1. Dependencies with other CSS 3 Modules > > Does it really depend on those modules? I think this section need to be > revised. Probably on all CSS3 modules as the graph that was produced a > few weeks ago doesn't seem to be correct. A specification that > implements the CSS3 Background module does not need the 'rgba' color > value for example. It would be nice, but it doesn't depend on it. > > * 2.1. Changes from CSS 2.1 > > There are new 'border' properties as well. 'box-shadow' wasn't in CSS > 2.1 either. > > * 5. The 'background-image' property > > # An image that is empty (zero width or zero height), that fails to > # download, or that otherwise cannot be displayed (e.g., because it is > # not in a supported image format) has the same effect as a non-empty > # transparent image. > > Wouldn't it be easier to specify that if an image can't be displayed the > initial value should be used instead? > > # If 'background-repeat' or 'background-position' has more > # comma-separated values than 'background-image', the series of values > # is repeated as needed. > > As the editor's note already mentioned, it makes more sense for > 'background-image' to determine the number of layer and let all the > extra values specified be ignored. > > Actually, it might make even more sense to fall back to the initial > value when one of the properties specifies a layer too much. For > 'background-image' that would be 'none' if either 'background-repeat' or > 'background-position' has more comma-separated values. > > # Editor's Note: Conformance properties for an image should be > # addressed here: MIME type image/*, require support for PNG, refer to > # profiles… > > I don't think it is up to the CSS WG to require support for images. > > * 6. The 'background-repeat' property > > # Should there also be values of "repeat-up", "repeat-down", > # "repeat-right", and "repeat-left" for this property? > > What exactly would these values do? > > I think it might be wise to specify how 'space' should work. I am aware > of a large discussion how 'letter-spacing' should be implemented exactly > and it would be nice if this module would specify in more detail how it > should work. (Personally I think the space at the edge should be halve > the space that is between the images.) > > * 8. The 'background-position' property > > It would be nice to have a way to position a background from somewhere > else than '0 0' (top left). Using the 'calc()' proposal to express what > I mean: > > background-position:calc(100%-5px) calc(100%-5px); > > ... it would be very nice if that was made possible. Perhaps using '-5px > -5px' or so. > > Or, to determinate the canvas in which the 'background-image' is drawn. > Such a possibility would also remove the need for the editor's note in > section 9 and probably remove the need for section 10. > > * 11. The 'background-size' property > > I'm not sure if this is useful at all. I don't see that a stretched -- > it is a better name, indeed -- image could work out nice and I expect > authors to not take advantages of the possiblities. This also introduces > complexity for UAs and all kinds of rounding issues/errors. I suggest > marking this as a feature at risk if it is desired by the WG to keep it. > > * 16. The 'border-style' properties > > I think this should specify that UAs are allowed to fallback to 'solid' > if they don't have an appropriate implementation for the specified > values. I think this might be useful for UAs implementating 'border-radius'. > > * 18. The 'border-image' property > > Again, this makes me wonder how UAs are going to do this "correctly". > The idea is quite nice, although it seems strange that a 'border' > property sets the background image... > > * 23. The background of the canvas > > I think the specification should not give any recommendations anymore to > authors. Most UAs have implemented support for 'background' on the root > element. (Even Internet Explorer, be it just for 'background-color'.) I > also think it should say XHTML/XML or just XML. > > * 26. Tests > > How can a basic test suite guarentee interoparable implementations? Test > suites have to be detailed. I'd argue tests are more important than the > specification. > > -- > Anne van Kesteren > <http://annevankesteren.nl/> > > -- http://www.ben-ward.co.uk
Received on Saturday, 9 April 2005 14:57:31 UTC