Re: [csswg-drafts] [css-color-3][css-color-4] why opacity is applied on premultiplied color ? (#7640)

> For any element where `opacity` is non-unity, that element and all it's children are rendered to an initially transparent black RGBA buffer (including the effect of any alpha components in the colors). The A channel of that buffer is then multiplied by the opacity. Then the modified buffer is composited against the background of that element.

I don't understand, in the example I give, I take this _element_
and I multiply its A , but also its RGB, by the opacity.

In the example that I give I approach the subject of premuliplication,
indeed, I apply the opacity on the premultiplied color obtained.
so I multiply A by the opacity, **and also (R*A, G*A,B*A)** by the opacity.
The color I get after these calculations matches the color  displayed on the screen

I probably didn't understand your answer. I ask the questions and read the answers via google translate

-- 
GitHub Notification of comment by letochagone
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/7640#issuecomment-1228093509 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config

Received on Friday, 26 August 2022 06:09:58 UTC