This gives a nice order and doesn't repeat like your example does:

#!/usr/bin/perl -w
use strict;

my @dx = ( -1, 0, 1, 0 );
my @dy = ( 0, -1, 0, 1 );

my ($centerX, $centerY) = (0, 0);
my @range = (1 .. 3);

foreach my $r (@range)
{
 my ($px, $py) = ($r, $r); # starting point
 foreach my $d (0..3)
 {
  foreach (1..$r*2)
  {
   $px += $dx[$d];
   $py += $dy[$d];
   printf "%d,%d\n", $px+$centerX, $py+$centerY;
  }
 }
}
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