Re: [css-backgrounds] Clarification proposal for border colors

On Monday 2015-09-14 15:24 +0000, Adenilson Cavalcanti wrote:
> Finally, we could suggest an algorithm to make it easier for browser implementors to have a defined behavior, as follows:
> 
> "
> Here is an algorithm example that you *may* use:
> - if color different from zero: scale original border color by 1/3 for
> lighter and 2/3 for darker color.
> - In case the color is black, fix channel colors as 30% and 70% of
> platform definition of black.
> “

For what it's worth, the Gecko algorithm is somewhat more
complicated, and implemented here:
https://hg.mozilla.org/mozilla-central/file/de0e763b5210/layout/base/nsCSSColorUtils.cpp#l12
(though I'm not sure how the background color input to that function
is calculated, or even whether it's nontrivial).

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
             Before I built a wall I'd ask to know
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