Hmm.. why use a hash for keys that are just consecutive integers starting at 0? And why write to a temporary file if you can feed the external process directly? Also, Perl knows lists; use the easier to maintain for(@LIST) form of for loops when you don't have special requirements. As well, post-increments return the value a variable had before incrementing it, so you don't need to do that in two steps. Finally, your wrap-around code can be expressed much more naturally using a modulo operation.

use strict;
use warnings;

my @COLOR = (
    "0 0 0",
    "0 0 1",
    "0 1 0",
    "0 1 1",
    "1 0 0",
    "1 0 1",
    "1 1 0",
    "1 1 1",
);

my $postscript = << 'END_POSTSCRIPT';
%!
72 72 scale
.25 .25 translate
/Courier findfont .095 scalefont setfont
END_POSTSCRIPT

my $sy1   = 1;
my $color = 0;

for my $y (1 .. 148) {
    my $sy = $sy1;

    $sy1 %= 10;

    for my $x (1 .. 130) {
        my $_x = $x * .060;
        my $_y = $y * .070;

        $postscript .= "$COLOR{$color} setrgbcolor\n";
        $postscript .= "$_x $_y  moveto ($sy) show\n";

        $sy = ($sy + 1) % 10;
        $color = ($color + 1) % 8;
    }
}

open '|-', my $lp, 'lp'
    or die "Couldn't spawn lp: $!\n";

print $lp $postscript;

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Please use strict and warnings, until you know when you don't need to. This is not just advice to appease the theorists in the ivory tower - making your code work with them will save you many a headache. See

  • Use strict warnings and diagnostics or die
  • Use strict warnings and diagnostics
  • Use strict and warnings

    • Makeshifts last the longest.

    In reply to Re^5: send color text to printer by Aristotle
    in thread send color text to printer by jhasting

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