#!/usr/bin/perl
use strict;
use warnings;
use Tk;
use Tk::Photo;
use Tk::JPEG;

#this one stores the photo objects in a hash 

my (%img_obj, @keys, $image);
my $count = 0;

my $main   = new MainWindow;

&load_images;

my $imglab = $main->Label(
              -height => 600,
	      -width => 600,
              -image => $image )->pack;
		 
my $label   = $main->Label()->pack;
my $label2  = $main->Label()->pack;

my $button1 = $main->Button(
    -text    => 'faster',
    -command => \&faster )->pack;

my $button2 = $main->Button(
    -text    => 'slower',
    -command => \&slower)->pack;


my $rpt    = 400;
my $min    = 60;     # increase this if it starts to freeze at fastest setting
my $max    = 5000;    # increase if you want more time per image
my $incdec = 20;      # default 50ms increase/decrease

my $time_this = $main->repeat( $rpt, \&show_pic );

$label2->configure( -text => $rpt );

MainLoop;

sub slower {
    return if $rpt > $max;
    $rpt += $incdec;
    $time_this->time($rpt);
    $label2->configure( -text => $rpt );
}

sub faster {
    return if $rpt < $min;
    $rpt -= $incdec;
    $time_this->time($rpt);
    $label2->configure( -text => $rpt );
}

sub show_pic {
    push (@keys,shift(@keys)); #circular list
    $image->blank;
    $imglab->configure(-image => $img_obj{ $keys[0] }  );
    $label->configure( -text => $keys[0] );
}

sub load_images {
    my @files = <pics/*.jpg>;
    foreach my $file (@files) {
         $img_obj{ $file } = $main->Photo(
                      '-format' => 'jpeg',
                      '-file'   => $file);
        }
  @keys = keys %img_obj;
  $image = $img_obj{ $keys[0] };
}
__END__