A unified color scheme?

[Nate Bargmann]

I've long kind of poked at the color scheme in Tlf but really haven't
done much about it.  As it is currently coded there are checks of the
TERM environment variable for the values of 'rxvt', 'xterm' and
'xterm-256color'.  I see no explicit test for a TERM value of 'linux'
but yet such a setting has an effect.

The Linux console generally features the classic VGA color palette
though it can be changed and I have found the Ubuntu releases to be
guilty of doing so.  In fact, I delved into this over this past winter
and came away with some understanding and wrote about it on my blog:

https://www.n0nb.us/blog/2020/02/coping-with-color-on-the-linux-console-and-xterm-and-friends/

The first half of the post concerns the console and the second half
Xterm and RXvt.

As the man page has carried mention that Tlf is a console program for a
long time, it appears the color scheme has been crafted for the console.
However, I suspect most of us run Tlf in a terminal emulator in a GUI
desktop and the colors don't match the console.  The difference is not
serious but it does show many inconsistencies.  For example, on the
console the header line is bright yellow text on a bright green
background.  In my experiments the terminal emulators simply cannot
display this combination.  A heavier weight of brown text on a bright
green background can be shown that is visually quite different from the
console.  This has to do with using the ncurses A_STANDOUT attribute on
the color pair that also inverts the color pair.

I've submitted a pull request that provides a sample Xresources file for
Xterm and URxvt to use a VGA color palette.  I've also attached
screenshots (I hope they make it through) that show Tlf on the console,
in an Xterm, and finally in URxvt.

I've tried invoking Tlf as 'TERM=xterm tlf' (TERM=xterm-256color works
too) on all three terminals and it appears to be the most consistent
color scheme.  Is this something we should aim for to simplify the code
a little bit, although I'll admit it may not be the most readable on the
console.  Instead, I think that simply unifying Xterm and URxvt and
leaving the console alone is a better idea.

73, Nate

-- 

"The optimist proclaims that we live in the best of all
possible worlds.  The pessimist fears this is true."

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