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Re: [CSS4 color][CSS4 transition] color pre-multiplied vs non pre-multiplied

From: Rik Cabanier <cabanier@gmail.com>
Date: Thu, 31 Jan 2013 20:48:38 -0800
Message-ID: <CAGN7qDDTyDHfenN_fJ_jOvZ-eexYBqRDCFv8gUdcquMHbj=72A@mail.gmail.com>
To: Alan Gresley <alan@css-class.com>
Cc: fantasai <fantasai.lists@inkedblade.net>, "www-style@w3.org" <www-style@w3.org>
On Thu, Jan 31, 2013 at 8:31 PM, Alan Gresley <alan@css-class.com> wrote:

> On 1/02/2013 2:25 PM, Rik Cabanier wrote:
>
>> So, can we fix the spec?
>>
>
> Yes. Changing the part here [1] regarding example 23 and the second note
> that discusses premultiplied color space.
>
> Giving an example of how to create a gradient from color to
> transparent-color like so:
>
>   linear-gradient(red, rgba(255,0,0,0))
>
>   linear-gradient(red, rgba(255,0,0,0) 50%, rgba(0,0,255,0) 50%, blue)
>
>
> Possibly consider a new way to trigger transparent-color:
>
>   linear-gradient(red, pre-transparent)
>
>   linear-gradient(red, pre-transparent, blue)
>
>
>  I volunteer to fix the implementation in FF and WK.
>>
>
>
> What would you fix in FF and what is WK?
>

FF = mozilla :-)
WK = WebKit

I would fix that transparent has a special meaning (meaning a transparent
version of the previous and next stop color)


>
> I would volunteer to create examples for gradients.
>
>
> Regarding transitioning of color. Maybe dealing with issue 7 [2]. If
> pre-transparent ever becomes a reality, then this is not an issue anymore
> and can be changed before transition is _un-prefixed_.
>

It seems that that ship has sailed. All browsers do it premultiplied so it
can't be changed.


>
>
> 1. http://dev.w3.org/csswg/css3-**images/#color-stop-syntax<http://dev.w3.org/csswg/css3-images/#color-stop-syntax>
> 2. http://dev.w3.org/csswg/css3-**transitions/#animatable-types<http://dev.w3.org/csswg/css3-transitions/#animatable-types>
>
> --
> Alan Gresley
> http://css-3d.org/
> http://css-class.com/
>
Received on Friday, 1 February 2013 04:49:05 GMT

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