Subject: Re: bug#34001: 26.1.90; :distant-foreground face property fails to work in most cases

From: "Basil L. Contovounesios" <[email-masked]>
Date: Mon, 21 Jan 2019 22:58:06 +0000

Tina Russell <[email-masked]> writes:

> I’m not the only one who’s noticed this; there’s a good StackExchange
> thread from 2015 here:
> https://emacs.stackexchange.com/questions/7982/ The author notes that
> there should be a user option to set the amount of “distance” (between
> foreground and background colors) that is required for
> distant-foreground to kick in

It would be nice if any work in this area took into consideration
existing efforts by Julien Danjou (CCed) in lisp/net/shr-color.el
(see e.g. user options shr-color-visible-luminance-min and
shr-color-visible-distance-min and function shr-color-visible).

For example, the library may end up either duplicating existing core
logic, or prove sufficiently useful that it is moved to a less
SHR-specific location (I'm just speculating).

> , and adds that a good way to measure
> color distance in real-world circumstances is described here:
> http://web.mst.edu/~rhall/web_design/color_readability.html A commenter
> suggested that he file a bug, but I can’t find an Emacs bug report
> related to this issue, so I’m filing this now.

FWIW, there has been some discussion of colour distances in bug#25525
and bug#30295:

  https://debbugs.gnu.org/25525
  https://debbugs.gnu.org/30295

-- 
Basil