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Re: CSS3 transition strangeness when using background-color:transparent;

From: Boris Zbarsky <bzbarsky@MIT.EDU>
Date: Fri, 29 Jan 2010 09:29:02 -0500
Message-ID: <4B62F0AE.4080507@mit.edu>
To: "Tab Atkins Jr." <jackalmage@gmail.com>
CC: www-style <www-style@w3.org>
On 1/29/10 9:21 AM, Tab Atkins Jr. wrote:
> Of course, if an author changes to rgba(0,0,0,0) specifically, it
> should indeed transition on all components, and darken as it fades.

Why?  Why would you ever want that?

> I'm not sure how annoying special-casing this would be, though.
> Implementors?  Is 'transparent' turned into rgba(0,0,0,0) at too early
> of a stage to make this convenient?

In Gecko, this happens at the point when specified values are converted 
to computed values.  Computed values are what's used as input to 

> Is is possible to special-case this?

Wouldn't it be better to just do the premultiplied thing?  Any time 
opacity is involved it seems to give more desirable results.

Received on Friday, 29 January 2010 14:29:37 UTC

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