Re: Diff mode faces

[Eli Zaretskii <eliz@gnu.org>]

> From: "Richard M. Stallman" <rms@gnu.org>
> CC: teirllm@dms.auburn.edu, eliz@gnu.org, emacs-devel@gnu.org,
> 	merlyn@stonehenge.com
> Date: Thu, 30 Jun 2005 17:30:23 -0400
> 
>     On TTY it classifies colors as follows:
> 
>     Dark:  black red green blue
>     Light: magenta yellow cyan white
> 
>     But on xterm it is quite different:
> 
>     Dark:  black red green blue magenta yellow cyan
>     Light: white
> 
> That anomaly could be worth fixing.

I think that's not an anomaly, but a bug.

Juri, can you explain how did this happen?  If that's an 8-color
xterm, then the code in tty-color-values should not distinguish
between xterm and any other 8-color TTY.  If the xterm in question
supports more than 8 colors, please tell the details, including how
many colors it supports, how were the colors set up, and how did you
test the above classification.

>     OTOH, the formula I proposed in January produces the same
>     classification on TTY, xterm and X as:
> 
>     Dark:  black red green blue magenta
>     Light: yellow cyan white
> 
> Could you propose it again now?

A formula that classifies red and magenta the same on X and on a TTY
is probably not very good, since the TTY's "red" is much darker that
the X's "red".  See the WARNING in the comments near the beginning of
tty-colors.el, for more about this.