RE: [css3-backgrounds] Example XV inconsistent with prose of section 3.6

Actually...
Background-position: center right 15px;
...is a better example because with the left example below you can get away with "17px 50%".

- Brian


> -----Original Message-----
> From: www-style-request@w3.org [mailto:www-style-request@w3.org] On
> Behalf Of Brian Manthos
> Sent: Tuesday, September 14, 2010 2:18 AM
> To: fantasai; Tab Atkins Jr.
> Cc: Sylvain Galineau; www-style@w3.org
> Subject: RE: [css3-backgrounds] Example XV inconsistent with prose of
> section 3.6
> 
> What does
>  Background-position: left 17px center;
> serialize out as?
> 
> "left 17px 50%"?
> 
> That seems to collide with
> "If three or four values are given, then each <percentage> or<length>
> represents an offset and must be preceded by a keyword, which specifies
> from which edge the offset is given."
> 
> Or are you saying center sometimes becomes 50% when serialized out, and
> sometimes doesn't?
> 
> Confused again,
> - Brian
> 
> 
> > -----Original Message-----
> > From: fantasai [mailto:fantasai.lists@inkedblade.net]
> > Sent: Tuesday, September 14, 2010 12:09 AM
> > To: Tab Atkins Jr.
> > Cc: Sylvain Galineau; Brian Manthos; www-style@w3.org
> > Subject: Re: [css3-backgrounds] Example XV inconsistent with prose of
> > section 3.6
> >
> > On 09/13/2010 06:22 PM, Tab Atkins Jr. wrote:
> > > On Mon, Sep 13, 2010 at 6:15 PM, Sylvain Galineau wrote:
> > >>>>> 'center' and '50%' are equivalent in the context of a
> > >>>>> background-
> > position.
> > >>>>
> > >>>> For rendering yes, for OM no...
> > >>>
> > >>> Ah, right.  Yeah, then that example is incorrect.
> > >>>
> > >> Why ? This module and its examples are not about the OM so I'm not
> > >> clear on why we can deem this example incorrect on OM grounds. But
> > >> beyond that why is 50% not equivalent to center in the OM ?
> > >
> > > Well, it's not specified in any significant way, but it would be
> > > expected that saying "center" would make the current OM return
> > > "center", and saying "50%" would make the current OM return "50%".
> >
> > IIRC, Anne was going to define OM and serialization bits consistent
> > with the Computed Values line wherever that gave enough detail. In
> > this particular instance, there is enough detail: keywords compute to
> percentage values.
> >    http://www.w3.org/TR/CSS21/colors.html#propdef-background-position

> >    http://www.w3.org/TR/css3-background/#the-background-position

> >
> > > The Values API that Anne's been floating would differentiate between
> > > the two as well, claiming the type of the value to be "keyword" and
> > > "percentage" respectively.  (Like it allows you to differentiate
> > > between "red" and "#f00".)
> >
> > Agreed with Sylvain on this one.
> >
> > ~fantasai

Received on Tuesday, 14 September 2010 09:43:22 UTC