#!/usr/bin/perl
use warnings;
use strict;
use Tk;

# stare at the cross-hairs, a pink orb 
# should appear rotating, where there is none 

my $mw = MainWindow->new();

# first create a canvas widget 
my $canvas = $mw->Canvas(width => 600, height => 600,
                -bg => 'gray',
                )->pack();


my %pos;
my $angle = 0;
my $radius = 200;
my $pos;
my $hidden = 0;

foreach my $pos(0..11){

my $x = 300 + sin($angle)*$radius;
my $y = 300 + cos($angle)*$radius;
my $x1 = $x - 40;
my $y1=  $y - 40;

$pos{$pos} = $canvas->createOval($x,$y,$x1,$y1,
                      -fill => 'green',
                      -outline=>'green',
                      -tags => [$pos],
                     # -stipple => 'gray75', 
                      );
$angle += .5236; # (pi / 180) * 30 
}

$canvas->createLine(260,280,300,280,
            -width=>5, -fill=>'black');
$canvas->createLine(280,260,,280,300,
            -width=>5, -fill=>'black');


my $ebutton = $mw->Button(-text => 'Exit',
                  -command => 'Tk::exit')->pack();

$pos = 0;
my $timer = $mw->repeat(100,sub{
      $canvas->itemconfigure($pos{$hidden} , -state => 'normal');
      $canvas->itemconfigure($pos{$pos}, -state => 'hidden');
            $hidden = $pos;
            $pos++;
            if($pos == 12){ $pos=0 };
       });

MainLoop();
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