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Re: [css3-images] Premultiplication switch

From: Tab Atkins Jr. <jackalmage@gmail.com>
Date: Mon, 1 Aug 2011 14:01:37 -0700
Message-ID: <CAAWBYDCtVb_yuWKph73QczzbyH=mF+hjvK7HtGNCcrAFCgWtsA@mail.gmail.com>
To: Alan Gresley <alan@css-class.com>
Cc: www-style@w3.org
On Sun, Jul 31, 2011 at 7:04 PM, Alan Gresley <alan@css-class.com> wrote:
> This may be one option but it would mean the introduction of potentially two
> formats for CSS4 color. They being prgba() and phsla().
>
> I would believe that gradients done with prgba() could not be transitioned
> to rgba() or gradients done with phsla() could not be transitioned to
> hsla().
>
> The benefit would be that both types, pre-multiplied and non-premultiplied
> gradients could share the same syntax without having to add some form of
> switch.

You don't even have to invoke transitions to make this problematic - a
single gradient couldn't use both pre- and post-multiplied colors
together in its stops.  Color transitions always have to be done in a
particular color-space, so different colors have to agree on what
color-space they're in, or else coerce each other into a common
colorspace.

~TJ
Received on Monday, 1 August 2011 21:02:23 GMT

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