&PolygonGravity( $image, [ 10,20, 40,70, 80,40, 30,10], $black);

sub PolygonGravity {
  my ($image, $points, @options) = @_;
  my @points = @$points;

  while (my ($x, $y, @points) = @points)) { # oder splice
    last unless defined $points[0]; last unless defined $points[1];
    $image->line($x, $y, @points[0,1], @options);
  } # while

  return $image;
} # PolygonGravity