From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Richard Stallman Newsgroups: gmane.emacs.devel Subject: Re: Automatic face setting based on contrast? Date: Wed, 06 Oct 2021 16:53:05 -0400 Message-ID: References: <87k0iub53g.fsf.ref@yahoo.com> <5052177.DnhJ6CHfxM@galex-713.eu> Reply-To: rms@gnu.org Content-Type: text/plain; charset=Utf-8 Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="29596"; mail-complaints-to="usenet@ciao.gmane.io" Cc: luangruo@yahoo.com, stefan@marxist.se, emacs-devel@gnu.org To: Alexandre Garreau Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Wed Oct 06 22:56:36 2021 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mYDxr-0007ST-5E for ged-emacs-devel@m.gmane-mx.org; Wed, 06 Oct 2021 22:56:35 +0200 Original-Received: from localhost ([::1]:37480 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mYDxq-0005tz-3s for ged-emacs-devel@m.gmane-mx.org; Wed, 06 Oct 2021 16:56:34 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:38520) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mYDuV-0002Ov-0F for emacs-devel@gnu.org; Wed, 06 Oct 2021 16:53:07 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:42058) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mYDuU-0001Qh-3E; Wed, 06 Oct 2021 16:53:06 -0400 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.90_1) (envelope-from ) id 1mYDuT-00057c-I4; Wed, 06 Oct 2021 16:53:05 -0400 In-Reply-To: <5052177.DnhJ6CHfxM@galex-713.eu> (message from Alexandre Garreau on Tue, 05 Oct 2021 23:20:30 +0200) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:276454 Archived-At: [[[ To any NSA and FBI agents reading my email: please consider ]]] [[[ whether defending the US Constitution against all enemies, ]]] [[[ foreign or domestic, requires you to follow Snowden's example. ]]] > > Could there be a kind of contrast-inheritance where face A > > is set automatically to contrast strongly with B, and contrast > > somewhat with C and D? Based on calculations on the RGB codes, > > I imagine. > I think it would be waaaaay more straightforward to use HSL code instead > of RGB. RGB is the lowest level possible, but difficult to master as a > human. The most meaningful way to specify colors is with HSL, which is to > me the most high level. I'm not trying to talk about details such as which coordinate system to use. If you get this to work, it will be an advance. Work out the details as yo like. -- Dr Richard Stallman (https://stallman.org) Chief GNUisance of the GNU Project (https://gnu.org) Founder, Free Software Foundation (https://fsf.org) Internet Hall-of-Famer (https://internethalloffame.org)