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Re: [css3-background] possibly too late for last call, but: background-opacity?

From: Giovanni Campagna <scampa.giovanni@gmail.com>
Date: Fri, 16 Oct 2009 13:59:53 +0200
Message-ID: <65307430910160459g612043c8h2c69b295504acbb4@mail.gmail.com>
To: Brad Kemper <brad.kemper@gmail.com>
Cc: Lee Owen <fleeboy@gmail.com>, www-style@w3.org
2009/10/16 Brad Kemper <brad.kemper@gmail.com>:
>
>
> On Thu, Oct 15, 2009 at 1:15 PM, Lee Owen <fleeboy@gmail.com> wrote:
>>
>> Thanks for your reply and your drop-shadow proposal page! Thats a very
>> flexible approach.
>> Could you target specific background images in a multi-background element?
>> For example:
>>  opacity:0.5; apply-to(opacity, background-image(1,2,4) +
>> background-color);
>
>
> Sorry, I kind of screwed that up the first time. I meant to write this:
>
> opacity:0.5;
> apply-effect:opacity, background-image + background-color;
>
> And you're right; I didn't originally account for multiple backgrounds. I
> like the way you have it, and would say
> that background-image and background-image(0) would be equivelent. So,
> without my messed up notation on using this as a property, it would actually
> look like this:
>
> opacity:0.5;
> apply-effect:opacity, background-image(1,2,4) + background-color;
>
>
>>
>> and would these properties be able to be animated?
>
>
> 'opacity' would be, but 'apply-effect' or 'visibility' would not be. It
> would just continue to be the same throughout. So, if the effect
> (opacity) only applied to the background, then you would be animating the
> opacity of the background, and leaving the borders opacity, etc. alone.

Does that mean that an element gets multiple "opacity" properties? Or
that you cannot set opacity different than auto for everything outside
the apply-effect selected portions?

And what about multiple effects? Do you use a syntax separator?
And how that composes with cascade, like if I want to set an opacity
effect for background somewhere and a drop shadow for the border image
in another selector?
Are "creative selectors" always needed?
(It seems an use case for the "cascade" keyword, but I know that this
is not much enjoyed by implementers)

Moreover, what about making it a part of affected properties, like:
opacity: 1.0 apply-to(background), 0.7 apply-to(content);

Or what if we go the IE / Mozilla way, by extending filter, adding
commas, functional notations for common filters and apply-to()
filter: opacity(0.5) apply-to(background), drop-shadow(10px,10px)
apply-to(border-image), "../filters/multicolorblur.xml"
apply-to(box-shadow),
url("progid:DXImageTransform.Microsoft.AlphaImageLoader(src=../images/shared/lvlogo.png,
sizingMethod='scale')") apply-to(all);

(this would make opacity obsolete, deprecated or syntactic sugar for
filter: opacity() apply-to(all));

Giovanni
Received on Friday, 16 October 2009 12:00:26 GMT

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