 Sample image
The task is to demonstrate the creation of a series of vertical pinstripes across the entire width of the display.

 in the first quarter the pinstripes should alternate one pixel white, one pixel black = 1 pixel wide vertical pinestripes
 Quarter of the way down the display, we can switch to a wider 2 pixel wide vertical pinstripe pattern, alternating two pixels white, two pixels black. 
 Half way down the display, we switch to 3 pixels wide, 
 for the lower quarter of the display we use 4 pixels.


c.f. Colour_pinstripe/Display

my ($x,$y) = 1280,720;
my @colors = 0, 1;
 
spurt "pinstripes.pgm", qq:to/EOH/ orelse .die;
    P5
    # pinstripes.pgm
    $x $y
    1
    EOH
 
my $img = open "pinstripes.pgm", :a, :bin orelse .die;
 
my $vzones = $y div 4;
for 1..4 -> $w {
    my $stripes = ceiling $x / $w / +@colors;
    my $line = Buf.new: (flat((@colors Xxx $w) xx $stripes).Array).splice(0,$x); # DH change 2015-12-20
    $img.write: $line for ^$vzones;
}
 
$img.close;