use GD;
my $img = new GD::Image ($width, $height);
my $black = $img->colorAllocate (0,0,0);
my $white = $img->colorAllocate (255,255,255);
map {
  my $polygon = GD::Polygon->new;
  map { $polygon->addPt (round ($_->[0] * $scale - $minx),
		         round ($maxy - $_->[1] * $scale)); } @{$_};
  $img->filledPolygon ($polygon,$white);
} @polygons;
print $img->png ();