[csswg-drafts] [css-transitions] Define interpolation of the currentcolor keyword

SimonSapin has just created a new issue for 
https://github.com/w3c/csswg-drafts:

== [css-transitions] Define interpolation of the currentcolor keyword 
==
Interpolation happens on computed values:

https://drafts.csswg.org/css-transitions/#transitions
> The computed value of a property transitions over time from the old 
value to the new value. 

The computed value for `<color>` is either a RGBA color or 
`currentcolor`:

https://drafts.csswg.org/css-color/#currentcolor-color
> The keyword `currentcolor` takes its value from the value of the 
color property on the same element. This happens at used-value time,

When defining how to interpolate `<color>`, css-transitions seems to 
assume it can only be an RGBA color:

https://drafts.csswg.org/css-transitions/#interpolated-types
> color: interpolated via red, green, blue and alpha components 
(treating each as a number, see below). The interpolation is done 
between premultiplied colors (that is, colors for which the red, 
green, and blue components specified have been multiplied by the 
alpha). 

The section in this last quote should define how `currentcolor` 
interpolates. Is it not interpolate, or should it be substituted by 
the value of `color` (which itself might be animated or transitioning)
 for the purpose of interpolation?

CC @Manishearth, @upsuper 

Please view or discuss this issue at 
https://github.com/w3c/csswg-drafts/issues/445 using your GitHub 
account

Received on Tuesday, 6 September 2016 07:36:14 UTC