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

my $mw = tkinit;


$mw->geometry("600x440+100+100");

my $canvas = $mw->Canvas(-width => 600, -height => 400,
                         -bg => 'black')->pack();

my $line;
$line = $canvas->createLine(0,200,100,200,400,200,600,200, 
                          -width => 5,
                          -smooth => 1,
			  -splinesteps => 20,
			  -fill => 'purple');


my $timer = $canvas->repeat(10,sub{
              $canvas->delete($line);

 my @vals = ( 0, 200, 200, 200 + rand 300, 400, 200 - rand 300, 600, 200);     

              $line = $canvas->createLine( @vals, 
                                  -width => 5,
                                  -smooth => 1,
	        		  -splinesteps => 20,
			         -fill => 'purple');
	      


       });

$mw->Button(-text=>'Quit',-command =>sub{exit})->pack;
MainLoop;