[csswg-drafts] [css-color-4] Missing info about Premultiplication and Undefined values (#7536)

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

== [css-color-4] Missing info about Premultiplication and Undefined values ==
In this issue (https://github.com/w3c/csswg-drafts/issues/7253) a change was made :

> If the alpha value is [none](https://www.w3.org/TR/css-color-4/#valdef-color-none), the premultiplied value is the un-premultiplied value. Otherwise,

I still feel this is a good call, but it is often referred that premultiplication happens before interpolation, which it does. Still, maybe it should be mentioned that at interpolation time, if given two colors (A and B), if one of the colors has an undefined alpha (we'll say A), and the other does not (B), then when A takes on the alpha value of B, it will need to premultiply on the fly before the actual interpolation takes place. This can be inspected and done ahead of time, but I think maybe it should be mentioned.


Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/7536 using your GitHub account


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Received on Tuesday, 26 July 2022 00:18:54 UTC