#!/usr/bin/perl

use Tk;

$radius = 3;

sub nextone {
  $canvas->delete('all');
  if ($n == $lines) {
    $_ = <>;
    exit unless $_;
    ($lines, $glyph) = split;
    $n = 0;
  }
  $n++;
  $label->configure(text => "'$glyph', $n of $lines");  
  $_ = <>;
  @a = split;
  $_ = shift(@a);
  $ox = shift @a;
  $oy = shift @a;
  $canvas->create('oval', $ox - $radius, $oy - $radius, $ox + $radius, $oy + $radius, fill => 'black');
  while(@a) {
    $x = shift @a;
    $y = shift @a;
    $canvas ->create(line, $ox, $oy, $x, $y);
    $ox = $x;
    $oy = $y;
  }
}

$top = MainWindow->new();
$canvas = $top->Canvas(width => 256, height => 256)->pack();
$button = $top->Button(text => 'Next', command => \&nextone)->pack();
$label = $top->Label(text => '')->pack();;

while(<>) {
  last if /^ /;
}
while(<>) {
  last if /^\d/;
}
($lines, $glyph) = split;
$n = 0;
nextone();

MainLoop();