Bug 12743 – box-shadow should not only be drawn on the outside of the box, but also "behind" it, in case the div is transparent

• Component: CSS
• Status: RESOLVED INVALID

[Alexander Kempgen]

box-shadow should not only be drawn on the outside of the box, but also "behind" it, in case the div is transparent. w3 hasn't decided on this yet: http://www.w3.org/TR/css3-background/#the-box-shadow

[Alexander Kempgen]

Created attachment 13132 [details]
testcase

[Alexander Kempgen]

Created attachment 13133 [details]
testcase fix

[Robert Blaut]

Literally reading CSS3 Background and Borders Module specifications: "They are drawn just outside the border edge" the bug report is INVALID.

It's even clearer in this sentence: "If an element has multiple boxes, all of them get drop shadows, but shadows are only drawn where borders would also be drawn". 

[Dave Hyatt]

I think this will end up being INVALID as well.

[Alexander Kempgen]

http://www.w3.org/TR/2005/WD-css3-background-20050216/#the-box-shadow (latest version, wip) still says "This example shows a shadow on the bottom right only, even though the box is transparent. Shouldn't we see a “real” shadow, projecting exactly the opaque parts of the box? What if the opaque parts are actually semi-opaque? Will the shadow be less intense there?" below example 1 in red though...

[Robert Blaut]

(In reply to comment #5)
> http://www.w3.org/TR/2005/WD-css3-background-20050216/#the-box-shadow (latest
> version, wip) still says "This example shows a shadow on the bottom right only,
> even though the box is transparent. Shouldn't we see a “real” shadow,
> projecting exactly the opaque parts of the box? What if the opaque parts are
> actually semi-opaque? Will the shadow be less intense there?" below example 1
> in red though...
> 

But these questions are only editor notes in working draft. They aren't a part of current WD. For now the bug is INVALID. It will be reopened in case of spec change.

[Dave Hyatt]

I don't think it's INVALID.  We should keep it open for now since the issue is still unresolved.

[Robert Blaut]

(In reply to comment #7)
> I don't think it's INVALID.  We should keep it open for now since the issue is
> still unresolved.
> 

So the bug should be changed to NEW if we agree the issue is VALID, isn't it?

[Dave Hyatt]

This bug is invalid now.

"An outer box-shadow casts a shadow as if the border-box of the element were opaque. The shadow is drawn outside the border edge only: it is clipped inside the border-box of the element. "