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From Rosetta Code
You are encouraged to solve this task according to the task description, using any language you may know.

The task is to demonstrate the creation of a series of 1 point wide vertical pinstripes with a sufficient number of pinstripes to span the entire width of the printed page (except for the last pinstripe). The pinstripes should alternate one point white, one point black. (Where the printer does not support producing graphics in terms of points, pixels may be substituted in this task.)

After the first inch of printing, we switch to a wider 2 point wide vertical pinstripe pattern. alternating two points white, two points black. We then switch to 3 points wide for the next inch, and then 4 points wide, etc. This trend continues for the entire length of the page (or for 12 inches of run length in the case of a printer using continuous roll stationery). After printing the test pattern the page is ejected (or the test pattern is rolled clear of the printer enclosure, in the case of continuous roll printers).

Note that it is an acceptable solution to use the smallest marks that the language provides, rather than working at native printer resolution, where this is not achievable from within the language.

Optionally, on systems where the printer resolution cannot be determined, it is permissible to prompt the user for printer resolution, and to calculate point size based on user input, enabling fractional point sizes to be used.


      PD_RETURNDC = 256
DIM pd{lStructSize%, hwndOwner%, hDevMode%, hDevNames%, \
\ hdc%, flags%, nFromPage{l&,h&}, nToPage{l&,h&}, \
\ nMinPage{l&,h&}, nMaxPage{l&,h&}, nCopies{l&,h&}, \
\ hInstance%, lCustData%, lpfnPrintHook%, lpfnSetupHook%, \
\ lpPrintTemplateName%, lpSetupTemplateName%, \
\ hPrintTemplate%, hSetupTemplate%}
pd.lStructSize% = DIM(pd{})
pd.hwndOwner% = @hwnd%
pd.flags% = PD_RETURNDC
SYS "PrintDlg", pd{} TO ok%
SYS "DeleteDC", @prthdc%
@prthdc% = pd.hdc%
*MARGINS 0,0,0,0
dx% = @[email protected]%!232
dy% = @[email protected]%!240
SYS "GetDeviceCaps", @prthdc%, _LOGPIXELSY TO dpi%
DIM rc{l%,t%,r%,b%}
SYS "CreateSolidBrush", 0 TO brush%
VDU 2,1,32,3
pitch% = 2
FOR y% = 0 TO dy% STEP dpi%
FOR x% = 0 TO dx%-pitch% STEP pitch%
rc.l% = x% : rc.r% = x% + pitch%/2
rc.t% = y% : rc.b% = y% + dpi%
SYS "FillRect", @prthdc%, rc{}, brush%
pitch% += 2
VDU 2,1,12,3

Liberty BASIC[edit]

Draws the pattern in a window onto a large graphic box, then dumps to the printer.

'paperW = 8.5 ' for US letter paper
'paperH = 11
paperW = 8.2677165 ' for A4 paper
paperH = 11.6929134
dpi= 300
prompt "Enter your printer DPI" +chr$( 13) + "(300 is OK for laser one, 360 likely for inkjet)"; dpi
w = paperW *dpi 'pixel size of paper
h = paperH *dpi
graphicbox, 0, 0, 300, 300 'picture could be bigger
open "Pinstripe/Printer" for window as #main
#main "trapclose [quit]" "autoresize" 'now we can maximize window with picture "down" "horizscrollbar on 0 "; w -300 'so we can scroll it "vertscrollbar on 0 "; h -300 "place 0 0" "color white" "boxfilled "; w; " ";h "color black" "backcolor black"
for i = 0 to int( paperH)
ww = i + 1
yy =( i + 1) * dpi
if yy > h then yy = h
for x = ww to w step ww * 2 'start with white strip
x1 = x + ww
if x1 >= w then x1 = w "place "; x; " "; i * dpi "boxfilled "; x1; " "; yy
next "flush" "print "; w
close #main


(load "@lib/ps.l")
(call 'lpr
(pdf "pinstripes"
(a4) # 595 x 842 dots
(for X 595
(gray (if (bit? 1 X) 0 100)
(vline X 0 842) ) )
(page) ) )


The drawing code is exactly the same code as Pinstripe/Display#Racket, only drawing onto a printer device context now.

#lang racket/gui
(define parts 4)
(define dc (new printer-dc%))
(send* dc (start-doc "Pinstripe") (start-page))
(define-values [W H] (send dc get-size))
(send dc set-pen "black" 0 'solid)
(send dc set-brush "black" 'solid)
(define H* (round (/ H parts)))
(for ([row parts])
(define Y (* row H*))
(for ([X (in-range 0 W (* (add1 row) 2))])
(send dc draw-rectangle X Y (add1 row) H*)))
(send* dc (end-page) (end-doc))


This code assumes that the page's printable area is 8.5"×11".

Library: Tk
package require Tk
# Allocate a temporary drawing surface
canvas .c
# Draw the output we want
for {set y 0;set dx 1} {$y < 11*72} {incr y 72;incr dx} {
for {set x 0;set c 0} {$x < 8.5*72} {incr x $dx;set c [expr {!$c}]} {
.c create rectangle $x $y [expr {$x+$dx+1}] [expr {$y+73}] \
-fill [lindex {black white} $c] -outline {}
# Send postscript to default printer, scaled 1 pixel -> 1 point
exec lp - << [.c postscript -height $y -width $x -pageheight $y -pagewidth $x]
# Explicit exit; no GUI desired