W3C home > Mailing lists > Public > www-style@w3.org > April 2012

Re: [css3-border][css3-background] border-radius with <angle>

From: Bert Bos <bert@w3.org>
Date: Thu, 5 Apr 2012 10:28:11 +0200
To: Christoph Päper <christoph.paeper@crissov.de>
Cc: www-style@w3.org
Message-Id: <201204051028.11573.bert@w3.org>
Hello Christoph,

Regarding your two suggestions for the Backgrounds and Borders module:

On Tuesday 13 March 2012 12:58:03 Christoph Päper wrote:
> The ‘border-radius’ properties accept two values for each corner,
[...]
> it’s really just one angle and its complement.
> 
> Since the two-value notation already looks like it specifies the
> tangent of the interior angle at the vertical edge or the exterior
> angle at the horizontal edge, I wondered whether border radius could
> also be specified with <angle> values. You would of course also need
> some kind of scaling factor, perhaps the lengths of the hypotenuse.
> 
>   border-radius: 37deg 5em;
> 
> would then specify (approximately) the same curved border as the
> example at the beginning.

We (the CSS WG) decided to _not_ make such a change to the module. We 
don't see a strong enough reason to add such a feature, certainly not at 
this time.

Please, let us know if you object to that decision.

> 
> This might not look as useful on its own, but imagine we wanted to
> introduce not rounded but “cut” corner shapes where the hypotenuse
> (or diameter) would become visible instead of some arc. (Shorthand)
> properties could then work like this:
> 
>   border-corner: _normal_ | curved | sharp
>   border-radius – if specified sets ‘border-corner’ to ‘curved’
> 
> or
> 
>   border-radius: <border-corner-shape>
>   border-cutoff: <border-corner-shape>
>   <border-corner-shape>: [ horizontal-radius [ / vertical-radius ]?
> 
>                          | <angle> diameter ]

We also decided _not_ to add these corner shapes to the module. 
(However, we did record them in the draft of a possible level 4 
module[1], so we can revisit the question later.)

Please, let us know if you object to that decision.

[1] http://dev.w3.org/csswg/css4-background/#border-corner-shape



For the CSS WG,
Bert
-- 
  Bert Bos                                ( W 3 C ) http://www.w3.org/
  http://www.w3.org/people/bos                               W3C/ERCIM
  bert@w3.org                             2004 Rt des Lucioles / BP 93
  +33 (0)4 92 38 76 92            06902 Sophia Antipolis Cedex, France
Received on Thursday, 5 April 2012 08:28:43 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 17:20:52 GMT