$mw->after( 1000, sub{ $hour = 3 } );
$mw->after( 1000, sub{ $minute = 30 } );

##</code><code>##

my $minute = 30;
$mw->update;
$mw->after( 1000, sub{ $minute++; } );

##</code><code>##

#!/usr/bin/perl
package Tk;
use Tk::Trace;

package main;
use Tk;
use Tk::Gauge;
use strict;
use warnings;


my $mw = MainWindow->new;

my( $hour, $minute ) = (12,12);

my $clock = $mw->Gauge(
    -extent               => -359.9, # 360 loses outline
    -from                 => 0,
    -huboutline           => 'black',
    -majortickinterval    => 5,
    -majorticklabelscale  => 12.0 / 60.0,
    -majorticklabelskip   => [ 0 ],
    -minortickinterval    => 1,
    -needles              => [
		              {
		                  -radius     => 100,
		                  -variable   => \$minute,
		              },
		              {
		                  -radius     => 60,
		                  -variable   => \$hour,
		              },
		             ] ,
    -start                => 90,
    -to                   => 60,
)->pack;

$mw->repeat(200 => sub {$hour = 1.2 * 5; $minute = 12; } );

MainLoop;