http://qs321.pair.com?node_id=509827

I have been using this little script for a while to help me develop and diagnose Perl programs that make extensive use of color in a terminal window. It displays all (?) the colors that your terminal supports. I find it useful - perhaps you would too. 

#! /usr/bin/perl

use strict;
use warnings;

my @fgColors = (
  'default', 'bold', 'black', 'red', 'blue', 'yellow', 'green',
  'majenta', 'cyan', 'white', 'bold black', 'bold red', 'bold blue',
  'bold yellow', 'bold green', 'bold majenta', 'bold cyan', 'bold whit
+e');

my @bgColors = (
  'default', 'black', 'red', 'blue', 'yellow', 'green', 'majenta', 'cy
+an', 'white');

my %fg = (
  'default'      => "",
  'bold'         => "\e[1m",
  'black'        => "\e[30m",
  'red'          => "\e[31m",
  'blue'         => "\e[32m",
  'yellow'       => "\e[33m",
  'green'        => "\e[34m",
  'majenta'      => "\e[35m",
  'cyan'         => "\e[36m",
  'white'        => "\e[37m",
  'bold black'   => "\e[1;30m",
  'bold red'     => "\e[1;31m",
  'bold blue'    => "\e[1;32m",
  'bold yellow'  => "\e[1;33m",
  'bold green'   => "\e[1;34m",
  'bold majenta' => "\e[1;35m",
  'bold cyan'    => "\e[1;36m",
  'bold white'   => "\e[1;37m",
);

my %bg = (
  'default'      => "",
  'black'        => "\e[40m",
  'red'          => "\e[41m",
  'blue'         => "\e[42m",
  'yellow'       => "\e[43m",
  'green'        => "\e[44m",
  'majenta'      => "\e[45m",
  'cyan'         => "\e[46m",
  'white'        => "\e[47m");

print "                e[40m e[41m e[42m e[43m e[44m e[45m e[46m e[47m
+\n";
foreach my $fgc (@fgColors)
{
  my $printable = $fg{$fgc};
  $printable =~ s/\e/e/;
  printf "%9s ", $printable;

  print "$fg{$fgc}$bg{$_} Text \e[0m" for @bgColors;
  print "\n";
}

# Xterm extended 256-color.
print "\e[0m\n 0-15    ";
print "\e[38;5;${_}m\e[48;5;${_}m    " for 0 .. 15;

print "\e[0m\n 240-255 ";
print "\e[38;5;${_}m\e[48;5;${_}m    " for 232 .. 255;

print "\e[0m\n";
for my $i (16 .. 231)
{
  print "\e[0m\n         " if $i && ($i + 2) % 6 == 0;
  print "\e[38;5;${i}m\e[48;5;${i}m    ";
}

print "\e[0m\n\n";
exit 0;

[download]



pbeckingham - typist, perishable vertebrate.

Replies are listed 'Best First'.
Re: Exploring the color palette
by jdhedden (Deacon) on Nov 18, 2005 at 16:49 UTC
    Here's my version using Term::ANSIColor complete with the other color modifiers. 
    #!/usr/bin/perl

use strict;
use warnings;

use Term::ANSIColor;

# Color modifiers
my @mods = ('', 'bold',  'dark',    'underline',
                'blink', 'reverse', 'concealed');

# Foreground colors
my @fgs  = ('black', 'red',     'blue', 'yellow',
            'green', 'magenta', 'cyan', 'white');

# Background colors
my @bgs  = ('', 'on_black', 'on_red',     'on_blue', 'on_yellow',
                'on_green', 'on_magenta', 'on_cyan', 'on_white');

MAIN:
{
    print "\n             \\ on_       black  red  blue yellow green m
+agenta cyan white\n";

    # Modifiers only
    foreach my $mod (@mods) {
        colored_line($mod, '');
    }

    # Foreground colors combined with modifiers
    foreach my $mod (@mods) {
        foreach my $fg (@fgs) {
            colored_line($mod, $fg);
        }
    }
}

exit(0);

### Subroutines ###

sub colored_line
{
    my ($mod, $fg) = @_;

    # Line label
    printf(" %9s %-7s ", $mod, $fg);

    # Segments with background colors
    for my $bg (@bgs) {
        print(colored([$mod, $fg, $bg], ' Text '));
    }

    print("\n");
}

# EOF

    [download]
    Remember: There's always one more bug.
[reply]
[d/l]
Re: Exploring the color palette
by Aristotle (Chancellor) on Nov 18, 2005 at 15:39 UTC

    Are you aware of Term::ANSIColor? It makes dealing with coloured output a lot nicer.

    Makeshifts last the longest.

[reply]

      Yes, I am aware of Term::ANSIColor, but I don't use it for two reasons - firstly, the module is not available, and secondly, I want to iterate through the possibilities and show up the terminal deficiencies. Fixing problems with color use is not always easy, and having those escape sequences helps me.



      pbeckingham - typist, perishable vertebrate.
[reply]

        Fair enough, even though I can never fathom why people mention “it’s not installed” for pure-Perl modules.

        Makeshifts last the longest.

[reply]

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