$main->Button(
    -text    => "Save",
    -command => [sub {
         $canvas->update;
         my @capture=();
         my ($x0,$y0,$x1,$y1)=$canvas->bbox('all');
         @capture=('-x'=>$x0,'-y'=>$y0,-height=>$y1-$y0,-width=>$x1-$x0);
         $canvas -> postscript(-colormode=>'color',
                               -file=>$0.'.ps',
			       -rotate=>0,
			       -width=>800,
			       -height=>500,    
			       @capture);
                               
			      } 
  ]  )->pack;