RE: [css3-backgrounds] Should a non-zero border-radius create a new stacking context ?

It's more composition work.

I'm not sure what you're saying though: is being consistent with inexplicability a goal ? Or are you saying that a new stacking context should be created even when border-radius is 0 ? The latter would be a much larger and likely breaking change for the web. One could certainly argue that it's disruptive to change z-ordering as a result of rounding a corner but we do that for opacity for reasons that are not so explicable to authors.


________________________________
From: Brad Kemper [brad.kemper@gmail.com]
Sent: Friday, November 19, 2010 2:42 PM
To: Sylvain Galineau
Cc: www-style@w3.org
Subject: Re: [css3-backgrounds] Should a non-zero border-radius create a new stacking context ?



On Nov 19, 2010, at 12:43 PM, Sylvain Galineau <sylvaing@microsoft.com<mailto:sylvaing@microsoft.com>> wrote:

Without the creation of a new stacking context, one can construct odd scenarios where a relatively positioned child is clipped to the curve while elements
outside its parent are layered in z-order underneath it. (see attached testcase in latest Firefox 4 Beta).

How is that any odder than the same situation where a relatively positioned child is clipped to a straight side or sharp corner.


It's not  clear to me why this is useful or desirable.

See this attached case, where the sharp-cornered clipping seems inexplicable to someone who doesn't know the mechanics of why it's happening.