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Re: [css3-background] should radii be capped?

From: fantasai <fantasai.lists@inkedblade.net>
Date: Tue, 21 Jul 2009 12:46:56 -0700
Message-ID: <4A661B30.7070106@inkedblade.net>
To: Håkon Wium Lie <howcome@opera.com>, www-style@w3.org
Håkon Wium Lie wrote:
> I've run into an issue where the specification for border-radius seems
> more limiting than necessary. Consider this test case and screenshot:
> 
>   http://people.opera.com/howcome/2009/tests/border-radius7.html
>   http://people.opera.com/howcome/2009/tests/border-radius7.png
> 
> The top part of the screenshot shows how Opera's internal
> implementation renders the test case, the bottom in Firefox 3.5.
> 
> I believe Firefox caps the radii as per the current specification [1]
> which states:
> 
>   The sum of two adjacent radii may not be more than the width or
>   height (whichever is relevant) of the box. If any sum exceeds that
>   value, all radii are reduced according to the following formula
> 
>    <nasty formula deleted>
> 
> Opera, however, doesn't cap the radii but attempts to honor them. I
> can see many uses for the elliptic expressions that this behavior
> allows. The spec, instead, will leave us with many stadium-like
> borders, as can be seen in the two leftmost Firefox renditions.

If you want an elliptic look, then set the two corner radii to two
different values. The goal of the formula is to preserve the shape
of the curve: if you want a different shape you should specify a
different shape.

~fantasai
Received on Tuesday, 21 July 2009 20:47:25 GMT

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