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Re: [css3-background]Positioning of box-shadow blurs?

From: Tab Atkins Jr. <jackalmage@gmail.com>
Date: Fri, 30 Apr 2010 16:56:16 -0700
Message-ID: <u2gdd0fbad1004301656tac2f6546x9631e2b6e160d420@mail.gmail.com>
To: Brad Kemper <brad.kemper@gmail.com>
Cc: Sylvain Galineau <sylvaing@microsoft.com>, Brian Manthos <brianman@microsoft.com>, Alex Meiburg <timeroot.alex@gmail.com>, "www-style@w3.org" <www-style@w3.org>
On Fri, Apr 30, 2010 at 4:47 PM, Brad Kemper <brad.kemper@gmail.com> wrote:
> Boy, it's getting a bit long for what I thought was a prety simple concept
> how about this:
>
> # The third length is a blur radius. Negative values are not allowed. The
> blurring region should be an area the width of this value, running along and
> centered on the edge of the shadow shape (a shape that otherwise mimics
> the shape of the border box, including any border-radius, absent the
> application of spread radius).  The shadow should transition from
> the shadow color on the inner edge of this region, to transparent at the
> outer edge of this region. If the blur radius is 0, the shadow has a sharp
> edge, otherwise the larger the value, the more the edge of the shadow is
> blurred.  The exact algorithm is not specified.
>
> #The fourth length is a spread radius. Positive values cause the shadow
> to expand in all directions by the specified radius. Negative values cause
> the shadow to contract. If 'border-radius' is zero, then corners should
> remain sharp (not rounded) after spread radius is applied and prior to the
> application of blur radius. Otherwise, the corners of the new shape will
> have radii equal to the corresponding 'border-radius' value plus the
> spread-radius value (or minus the spread-radius value if it is an inset
> shadow, but no less than zero for the final spread shadow corner radius).

I'm still slightly meh about the discontinuity in border-radius, but
otherwise I like the precision in the new text.

~TJ
Received on Friday, 30 April 2010 23:57:08 GMT

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