Source code in the basic programming language

 100  DATA 0,2, 6,10,5, 6, 7,15
 110  DATA 0,1, 3,10,5, 3,11,15
 120  DATA 0,8, 9,10,5, 9,13,15
 130  DATA 0,4,12,10,5,12,14,15
 140  LET C = 7
 150  POKE 768,169: REM LDA #
 160  POKE 770,073: REM EOR #
 170  POKE 772,133: REM STA
 180  POKE 773,235: REM   $EB
 190  POKE 774,096: REM RTS
 200  GR 
 210  FOR H = 0 TO 1
 220      FOR W = 0 TO 1
 230          FOR S = 0 TO C
 240              READ C(S)
 250          NEXT S
 260          FOR Y = 0 TO C
 270              POKE 769,Y
 280              LET Y1 = H * S * 2 + Y * 2
 290              FOR X = 0 TO C
 300                  POKE 771,X
 310                  CALL 768
 320                  COLOR= C( PEEK (235))
 330                  VLIN Y1,Y1 + 1 AT W * S + X
 340                  NEXT X,Y,W,H

      size% = 256

      VDU 23,22,size%;size%;8,8,16,0
      OFF

      DIM coltab%(size%-1)
      FOR I% = 0 TO size%-1
        coltab%(I%) = ((I% AND &FF) * &010101) EOR &FF0000
      NEXT

      GCOL 1
      FOR I% = 0 TO size%-1
        FOR J% = 0 TO size%-1
          C% = coltab%(I% EOR J%)
          COLOUR 1, C%, C%>>8, C%>>16
          PLOT I%*2, J%*2
        NEXT
      NEXT I%

      REPEAT WAIT 1 : UNTIL FALSE


100 FOR I=0 TO 24
110 : Y=INT(I*127/24)
120 : FOR J=0 TO 39
130 :   X=INT(J*127/39)
140 :   HL = (X OR Y) AND NOT (X AND Y)
150 :   H = INT(HL / 8)
160 :   L = HL - 8 * H
170 :   POKE 2048+I*40+J,L*16+H
180 :   POKE 3072+I*40+J,160
190 : NEXT J
210 NEXT I
220 GETKEY K$


let s = 255

for y = 0 to s

	for x = 0 to s

		let r = x ~ y
		fgcolor  r, r * 2, r * 3
		dot x, y

		wait

	next x

next y


' version 03-11-2016
' compile with: fbc -s gui

Dim As ULong x, y, r, w = 256

ScreenRes w, w, 32

For x = 0 To w -1
    For y = 0 To w -1
        r =(x Xor y) And 255
        PSet(x, y), RGB(r, r , r)         ' gray scale
        ' PSet(x, y), RGB(r, 255 - r, 0)  ' red + green
        ' PSet(x, y), RGB(r, 0, 0)        ' red
    Next
Next

' empty keyboard buffer
While Inkey <> "" : Wend
WindowTitle "Close window or hit any key to end program"
Sleep
End

    nomainwin

    w =512
    '   allow for title bar and window border
    WindowWidth  =w +2
    WindowHeight =w +34

    open "XOR Pattern" for graphics_nsb_nf as #w

    #w "trapclose quit"

    #w "down"

    for x =0 to w -1
        for y =0 to w -1
            b =( x xor y) and 255
            print b
            #w "color "; 255 -b; " "; b /2; " "; b
            #w "set "; x; " "; w -y -1
            scan
        next y
    next x

    #w "flush"

    wait

    sub quit j$
    close #w
    end
    end sub

' Munching squares - smallbasic  - 27/07/2018
  size=256
  GraphicsWindow.Width=size
  GraphicsWindow.Height=size
  For i=0 To size-1
    For j=0 To size-1
      BitXor() 'color=i Xor j
      GraphicsWindow.SetPixel(i,j,GraphicsWindow.GetColorFromRGB(0,color,color))
    EndFor
  EndFor

Sub BitXor '(i,j)->color
  n=i
  Int2Bit()
  ib=ret
  n=j
  Int2Bit()
  jb=ret
  color=0
  For k=1 to 8
    ki=Text.GetSubText(ib,k,1)
    kj=Text.GetSubText(jb,k,1)
    If ki="1" Or kj="1" Then
      kk="1"
    Else
      kk="0"
    EndIf
    If ki="1" And kj="1" Then
      kk="0"
    EndIf
    color=2*color+kk
  EndFor
EndSub 

Sub Int2Bit 'n->ret
  x=n
  ret=""
  For k=1 to 8
    t=Math.Floor(x/2)
    r=Math.Remainder(x,2)
    ret=Text.Append(r,ret)
    x=t
  EndFor
EndSub

#palletteSize = 128
Procedure.f XorPattern(x, y) ;compute the gradient value from the pixel values
  Protected result = x ! y
  ProcedureReturn Mod(result, #palletteSize) / #palletteSize
EndProcedure

Procedure drawPattern()
  StartDrawing(ImageOutput(0))
    DrawingMode(#PB_2DDrawing_Gradient)
    CustomGradient(@XorPattern())
    ;specify a gradient pallette from which only specific indexes will be used
    For i = 1 To #palletteSize 
      GradientColor(1 / i, i * $BACE9B) ; or alternatively use $BEEFDEAD
    Next 
    Box(0, 0, ImageWidth(0), ImageHeight(0))
  StopDrawing()
EndProcedure

If OpenWindow(0, 0, 0, 128, 128, "XOR Pattern", #PB_Window_SystemMenu)
  CreateImage(0, WindowWidth(0), WindowHeight(0))
  drawPattern()
  ImageGadget(0, 0, 0, ImageWidth(0), ImageHeight(0), ImageID(0))
  Repeat
    event = WaitWindowEvent(20)
  Until event = #PB_Event_CloseWindow
EndIf

w = 254

SCREEN 13
VIEW (0, 0)-(w / 2, w / 2), , 0

FOR x = 0 TO w
    FOR y = 0 TO w
        COLOR ((x XOR y) AND 255)
        PSET (x, y)
    NEXT y
NEXT x


'Munching squares
DECLARE SUB PaintCanvas

CREATE Form AS QForm
  ClientWidth  = 256
  ClientHeight = 256
  CREATE Canvas AS QCanvas
    Height = Form.ClientHeight
    Width  = Form.ClientWidth
    OnPaint = PaintCanvas
  END CREATE
END CREATE

SUB PaintCanvas
  FOR X = 0 TO Canvas.Width - 1
    FOR Y = 0 TO Canvas.Width - 1
      R = (X XOR Y) AND 255
      Canvas.Pset(X, Y, RGB(R, R, R)) ' gray scale
      'Canvas.Pset(X, Y, RGB(R, 255 - R, 0)) ' red + green
      'Canvas.Pset(X, Y, RGB(R, 0, 0)) ' red
    NEXT Y
  NEXT X
END SUB

Form.ShowModal

w = 100
graphic #g, w,w
for x = 0 to w
  for y = 0 to w
    b = (x xor y) and 255
    #g color(255 -b,b /2,b)
    #g "set "; x; " "; w -y -1
  next y
next x
render #g 
#g "flush"

PROGRAM:XORPATT
" •.-,+-°-1+o*:πOX"→Str1

ClrHome

{0,0,0,0}→L1
{0,0,0,0)→L2

For(I,1,8,1)
For(J,1,16,1)
J→A
I→B

If A>8
Then
A-8→A
1→L1(1)
Else
0→L1(1)
End

If A>4
Then
A-4→A
1→L1(2)
Else
0→L1(2)
End

If A>2
Then
A-2→A
1→L1(3)
Else
0→L1(3)
End

If A>1
Then
1→L1(4)
Else
0→L1(4)
End

0→L2(1)

If B>4
Then
B-4→B
1→L2(2)
Else
0→L2(2)
End

If B>2
Then
B-2→B
1→L2(3)
Else
0→L2(3)
End

If B>1
Then
1→L2(4)
Else
0→L2(4)
End

L1≠L2→L3
8L3(1)+4L3(2)+2L3(3)+L3(4)→C
Output(I,J,sub(Str1,C+1,1))

End
End
Pause

' Munching squares - 27/07/2018
Public Class MunchingSquares
    Const xsize = 256
    Dim BMP As New Drawing.Bitmap(xsize, xsize)
    Dim GFX As Graphics = Graphics.FromImage(BMP)

    Private Sub MunchingSquares_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint
        'draw
        Dim MyGraph As Graphics = Me.CreateGraphics
        Dim nColor As Color
        Dim i, j, cp As Integer
        xPictureBox.Image = BMP
        For i = 0 To xsize - 1
            For j = 0 To xsize - 1
                cp = i Xor j
                nColor = Color.FromArgb(cp, 0, cp)
                BMP.SetPixel(i, j, nColor)
            Next j
        Next i
    End Sub 'Paint

End Class


w = 256
 
open window w, w
 
For x = 0 To w-1
    For y = 0 To w-1
        r =and(xor(x, y), 255)
        color r, and(r*2, 255), and(r*3, 255)
        dot x, y
    Next
Next