Colour bars/Display
You are encouraged to solve this task according to the task description, using any language you may know.
- Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
- the system palette, or
- the sequence of colors:
- black
- red
- green
- blue
- magenta
- cyan
- yellow
- white
6502 Assembly
Implemented using Easy6502, this displays a pinstripe using the system palette. There are 16 colors, and the bottom 4 bits of A are the color index.
lda #0
tax
tay ;clear regs
;video ram on Easy6502 is four pages ranging from $0200-$0500
loop:
sta $0200,x
sta $0220,x
sta $0240,x
sta $0260,x
sta $0280,x
sta $02A0,x
sta $02C0,x
sta $02E0,x
sta $0300,x
sta $0320,x
sta $0340,x
sta $0360,x
sta $0380,x
sta $03A0,x
sta $03C0,x
sta $03E0,x
sta $0400,x
sta $0420,x
sta $0440,x
sta $0460,x
sta $0480,x
sta $04A0,x
sta $04C0,x
sta $04E0,x
sta $0500,x
sta $0520,x
sta $0540,x
sta $0560,x
sta $0580,x
sta $05A0,x
sta $05C0,x
sta $05E0,x
inx
txa ;effectively increment A
cpx #$20 ;32 columns of video memory
beq exit
jmp loop
exit:
brk ;on easy6502 this terminates a program.
Action!
PROC Main()
BYTE
i,
CH=$02FC, ;Internal hardware value for last key pressed
PALNTSC=$D014, ;To check if PAL or NTSC system is used
PCOLR0=$02C0,PCOLR1=$02C1,
PCOLR2=$02C2,PCOLR3=$02C3,
COLOR0=$02C4,COLOR1=$02C5,
COLOR2=$02C6,COLOR3=$02C7,
COLOR4=$02C8
Graphics(10)
PCOLR0=$04 ;gray
PCOLR1=$00 ;black
IF PALNTSC=15 THEN
PCOLR2=$42 ;red for NTSC
PCOLR3=$C6 ;green for NTSC
COLOR0=$84 ;blue for NTSC
COLOR1=$66 ;magenta for NTSC
COLOR2=$A6 ;cyan for NTSC
COLOR3=$FC ;yellow for NTSC
ELSE
PCOLR2=$22 ;red for PAL
PCOLR3=$B6 ;green for PAL
COLOR0=$74 ;blue for PAL
COLOR1=$48 ;magenta for PAL
COLOR2=$96 ;cyan for PAL
COLOR3=$EC ;yellow for PAL
FI
COLOR4=$0F ;white
FOR i=0 TO 79
DO
Color=i/10+1
Plot(i,0)
DrawTo(i,191)
OD
DO UNTIL CH#$FF OD
CH=$FF
RETURN
- Output:
Screenshot from Atari 8-bit computer
ActionScript
package {
import flash.display.Sprite;
import flash.events.Event;
public class ColourBars extends Sprite {
public function ColourBars():void {
if (stage) init();
else addEventListener(Event.ADDED_TO_STAGE, init);
}
private function init(e:Event = null):void {
var colours:Array = [ 0x000000, 0xFF0000, 0x00FF00, 0x0000FF, 0xFF00FF, 0x00FFFF, 0xFFFF00, 0xFFFFFF ];
var w:Number = stage.stageWidth / 8, h:Number = stage.stageHeight;
var x:Number = 0, i:uint, c:uint;
for ( i = 0; i < 8; i++ ) {
c = colours[i];
graphics.beginFill(c);
graphics.drawRect(w * i, 0, w, h);
}
}
}
}
Ada
with SDL.Video.Windows.Makers;
with SDL.Video.Renderers.Makers;
with SDL.Video.Palettes;
with SDL.Events.Events;
with SDL.Events.Keyboards;
procedure Colour_Bars_Display is
use type SDL.Events.Event_Types;
use SDL.C;
Colours : constant array (0 .. 7) of SDL.Video.Palettes.Colour :=
((0, 0, 0, 255), (255, 0, 0, 255),
(0, 255, 0, 255), (0, 0, 255, 255),
(255, 0, 255, 255), (0, 255, 255, 255),
(255, 255, 0, 255), (255, 255, 255, 255));
Window : SDL.Video.Windows.Window;
Renderer : SDL.Video.Renderers.Renderer;
Event : SDL.Events.Events.Events;
Bar_Width : int;
begin
if not SDL.Initialise (Flags => SDL.Enable_Screen) then
return;
end if;
SDL.Video.Windows.Makers.Create (Win => Window,
Title => "",
Position => SDL.Natural_Coordinates'(0, 0),
Size => SDL.Positive_Sizes'(0, 0),
Flags => SDL.Video.Windows.Full_Screen_Desktop);
SDL.Video.Renderers.Makers.Create (Renderer, Window.Get_Surface);
Bar_Width := Window.Get_Size.Width / 8;
for A in Colours'Range loop
Renderer.Set_Draw_Colour (Colour => Colours (A));
Renderer.Fill (Rectangle => (X => SDL.C.int (A) * Bar_Width, Y => 0,
Width => Bar_Width,
Height => Window.Get_Size.Height));
end loop;
Window.Update_Surface;
Wait_Loop : loop
while SDL.Events.Events.Poll (Event) loop
exit Wait_Loop when Event.Common.Event_Type = SDL.Events.Keyboards.Key_Down;
end loop;
delay 0.050;
end loop Wait_Loop;
Window.Finalize;
SDL.Finalise;
end Colour_Bars_Display;
AutoHotkey
(available at http://www.autohotkey.net/~tic/Gdip.ahk)
#SingleInstance, Force
#NoEnv
SetBatchLines, -1
; Uncomment if Gdip.ahk is not in your standard library
;#Include, Gdip.ahk
; Start gdi+
If !pToken := Gdip_Startup()
{
message =
( LTrim
gdiplus error!, Gdiplus failed to start.
Please ensure you have gdiplus on your system.
)
MsgBox, 48, %message%
ExitApp
}
OnExit, Exit
; Set the width and height we want as our drawing area, to draw everything in.
; This will be the dimensions of our bitmap
Width := A_ScreenWidth, Height := A_ScreenHeight
; Create a layered window
; (+E0x80000 : must be used for UpdateLayeredWindow to work!)
; that is always on top (+AlwaysOnTop), has no taskbar entry or caption
Gui, 1: -Caption +E0x80000 +LastFound +OwnDialogs +Owner +AlwaysOnTop
; Show the window
Gui, 1: Show, NA
; Get a handle to this window we have created in order to update it later
hwnd1 := WinExist()
; Create a gdi bitmap with width and height of what we are going to
; draw into it. This is the entire drawing area for everything
hbm := CreateDIBSection(Width, Height)
; Get a device context compatible with the screen
hdc := CreateCompatibleDC()
; Select the bitmap into the device context
obm := SelectObject(hdc, hbm)
; Get a pointer to the graphics of the bitmap, for use with drawing functions
G := Gdip_GraphicsFromHDC(hdc)
; ARGB = Transparency, Red, Green, Blue
Colors := "0xFF000000,0xFFFF0000,0xFF00FF00,0xFF0000FF"
Colors .= ",0xFFFF00FF,0xFF00FFFF,0xFFFFFF00,0xFFFFFFFF"
; This list ^ is Black, Red, Green, Blue, Magenta, Cyan, Yellow, White
StringSplit Colors, Colors, `,
w := Width // Colors0
Loop % Colors0
{
; Create a brush to draw a rectangle
pBrush := Gdip_BrushCreateSolid(Colors%A_Index%)
; Fill the graphics of the bitmap with a rectangle using the brush created
Gdip_FillRectangle(G, pBrush, w*(A_Index-1), 0, w, height)
; Delete the brush as it is no longer needed and wastes memory
Gdip_DeleteBrush(pBrush)
}
; Update the specified window we have created (hwnd1) with a handle to our
; bitmap (hdc), specifying the x,y,w,h we want it positioned on our screen
; So this will position our gui at (0,0) with the Width and
; Height specified earlier
UpdateLayeredWindow(hwnd1, hdc, 0, 0, Width, Height)
; Select the object back into the hdc
SelectObject(hdc, obm)
; Now the bitmap may be deleted
DeleteObject(hbm)
; Also the device context related to the bitmap may be deleted
DeleteDC(hdc)
; The graphics may now be deleted
Gdip_DeleteGraphics(G)
Return
;#######################################################################
GuiEscape:
Exit:
; gdi+ may now be shutdown on exiting the program
Gdip_Shutdown(pToken)
ExitApp
Return
AWK
BEGIN {
nrcolors = 8
for (height=0; height<20; height++) {
for (width=0; width<nrcolors; width++) {
# print (ANSI) basic color and amount of spaces
printf("\033[%dm%*s", width + 40, 64 / nrcolors, " ")
}
# reset color and print newline
printf("\033[0m\n")
}
}
BASIC
AmigaBASIC
SCREEN 1,320,200,5,1
WINDOW 2,"Color bars",(0,10)-(297,186),15,1
FOR a=0 TO 300
LINE (a,0)-(a,186),(a+10)/10
NEXT
loop: GOTO loop
Applesoft BASIC
1 DATA1,12,6,3,14,13,15
2 HOME : GR : FOR I = 1 TO 7
3 READ C(I) : NEXT
4 FOR I = 0 TO 39
5 COLOR= C(I / 5)
6 VLIN 0,39 AT I : NEXT
BBC BASIC
SW_MAXIMIZE = 3
SYS "ShowWindow", @hwnd%, SW_MAXIMIZE
VDU 26
W% = @vdu%!208 / 4
H% = @vdu%!212 * 2
COLOUR 1,9
COLOUR 2,10
COLOUR 3,12
COLOUR 4,13
COLOUR 5,14
COLOUR 6,11
COLOUR 7,15
FOR C% = 0 TO 7
GCOL C%
RECTANGLE FILL C%*W%, 0, W%, H%
NEXT
Chipmunk Basic
The sequence of colors.
100 rem Colour bars/Display
110 graphics 0 : graphics cls
120 for i = 0 to 7
130 read r,g,b
140 graphics color r,g,b
150 for j = 0 to 79
160 x = i*80+j
170 graphics moveto x,0
180 graphics lineto x,399
190 next j
200 next i
500 data 0,0,0 : rem black
510 data 100,0,0 : rem red
520 data 0,100,0 : rem green
530 data 0,0,100 : rem blue
540 data 100,0,100 : rem magenta
550 data 0,100,100 : rem cyan
560 data 100,100,0 : rem yellow
570 data 100,100,100 : rem white
Commodore BASIC
This task achieved only on Commodore computers with color capabilities. The example below tested as-is in VICE on the following machines:
- Commodore 64
- Commodore 128
- Commodore Plus 4
- Commodore CBM-II (with VIC-II video)
- Commodore SX-64
It will also work well on the VIC-20 if you either omit line 310 or comment (REM) it out as the VIC-20 has only an eight-color palette.
This cross-compatibility is achieved by using the PETSCII control codes (CHR$(x)) for changing color, which are generally the same across all platforms, although the system palettes themselves may differ. This is combined with printing a "reverse video" space (solid block) character in the color selected.
5 rem color bars program
10 print chr$(147);:dim co(17):c=1
20 read co(c):if co(c)>0 then c=c+1:goto 20
25 sp$=" ":h=22:c=c-1:rem sp$=5 spaces
30 for r=1 to c step int(c/2)
40 for h=1 to 10
50 for b=r to (r+int(c/2))-1
60 print chr$(18);chr$(co(b));sp$;
70 next b
75 rem check if palette is only 8 (vic-20).
76 rem if so, we need to fill the last two spaces.
80 if c<=8 then print " ";
90 next h:next r
100 get k$:if k$="" then 100
110 end
280 rem because the control codes for color are non-sequential,
285 rem we put them into a sequential array for use
300 data 144,5,28,159,156,30,31,158
305 rem omit or rem the next line for vic-20
310 data 129,149,150,151,152,153,154,155
320 data 0:rem data terminato
FreeBASIC
' FB 1.05.0 Win64
' Draw the color bars on an 80 x 25 console using the system palette of 16 colors
' i.e. 5 columns per color
Width 80, 25
Shell "cls"
Locate ,, 0 '' turn cursor off
For clr As UInteger = 0 To 15
Color 0, clr
For row As Integer = 1 to 25
Locate row, clr * 5 + 1
Print Space(5);
Next row
Next clr
Sleep
' restore default settings
Locate ,, 1 '' turn cursor on
Color 7, 0 '' white text on black background
Gambas
Public Sub Form_Open()
Dim iColour As Integer[] = [Color.Black, Color.red, Color.Green, Color.Magenta, Color.Cyan, Color.Yellow, Color.white]
Dim hPanel As Panel
Dim siCount As Short
With Me
.Arrangement = Arrange.Horizontal
.Height = 300
.Width = 400
End With
For siCount = 0 To 6
hpanel = New Panel(Me)
hpanel.Expand = True
hpanel.H = 500
HPanel.Background = iColour[siCount]
Next
End
IS-BASIC
100 GRAPHICS LORES 16
110 SET PALETTE BLACK,RED,GREEN,BLUE,MAGENTA,CYAN,YELLOW,WHITE
120 FOR I=1 TO 7
130 CALL BAR(I)
140 NEXT
150 DEF BAR(C)
160 SET INK C
170 PLOT C*160,0;C*160,719;C*160+152,719;C*160+152,0;C*160,0
180 PLOT C*160+16,16,PAINT
190 END DEF
Liberty BASIC
nomainwin
colors$="black red green blue pink cyan yellow white"
WindowWidth=DisplayWidth:WindowHeight=DisplayHeight
UpperLeftX=1:UpperLeftY=1
barWidth=DisplayWidth/8
graphicbox #main.g, 0,0,DisplayWidth,DisplayHeight
open "" for window_popup as #main
#main "trapclose [quit]"
#main.g "down; setfocus; when characterInput [quit]"
#main.g "when leftButtonUp [quit]"
#main.g "size ";barWidth
for x = barWidth/2 to DisplayWidth step barWidth
i=i+1
if i>8 then i=1
col$=word$(colors$,i)
#main.g "color ";col$;"; line ";x;" 0 ";x;" ";DisplayHeight
next
wait
[quit] close #main:end
Locomotive Basic
Show the default MODE 0 palette (includes two blinking colors at the end):
10 MODE 0:BORDER 23
20 FOR x=0 TO 15
30 ORIGIN x*40,0
40 FOR z=0 TO 39 STEP 4:MOVE z,0:DRAW z,400,x:NEXT z
50 NEXT x
60 CALL &bb06 ' wait for key press
PureBasic
Press Enter or Escape to exit the program.
Dim color(7)
color(0) = RGB($00, $00, $00) ;black
color(1) = RGB($FF, $00, $00) ;red
color(2) = RGB($00, $FF, $00) ;green
color(3) = RGB($00, $00, $FF) ;blue
color(4) = RGB($FF, $00, $FF) ;magenta
color(5) = RGB($00, $FF, $FF) ;cyan
color(6) = RGB($FF, $FF, $00) ;yellow
color(7) = RGB($FF, $FF, $FF) ;white
If Not InitKeyboard(): End: EndIf ;can't init keyboard
If Not InitSprite(): End: EndIf ;can't init sprite/screen library
If Not ExamineDesktops(): End: EndIf ;can't retrieve information about desktop
height = DesktopHeight(0)
width = DesktopWidth(0)
depth = DesktopDepth(0)
If OpenScreen(width, height, depth, "Press ENTER to exit")
StartDrawing(ScreenOutput())
For c = 0 To 7
Box((width * c) / 8, 0, width / 8, height, color(c))
Next
StopDrawing()
FlipBuffers()
Repeat
Delay(10)
ExamineKeyboard()
Until KeyboardPushed(#PB_Key_Escape) Or KeyboardPushed(#PB_Key_Return)
CloseScreen()
EndIf
Alternate method using console
DataSection
;Black, Red, Green, Blue, Magenta, Cyan, Yellow, White
Data.i 0, 12, 10, 9, 13, 11, 14, 15
EndDataSection
Dim colors(7)
For c = 0 To 7
Read.i colors(c)
Next
If OpenConsole()
;The console display is 80 columns wide by 25 rows
For r = 0 To 24
For c = 0 To 7
ConsoleColor(colors(c), colors(c))
Print(Space(80 / 8))
Next
Next
EnableGraphicalConsole(1)
ConsoleLocate(0, 0)
ConsoleTitle("Press ENTER to exit"): Input()
CloseConsole()
EndIf
Run BASIC
colors$ = "black,red,green,blue,magenta,cyan,yellow,white"
html "<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=4><tr height=70>"
for i = 1 to 8
html "<td width=20 bgcolor='";word$(colors$,i,",");"'</td>"
next i
html "</tr></table>"
Output
SmileBASIC
FOR I=0 TO 7
READ R,G,B
GFILL I*50,0,I*50+49,239,RGB(R,G,B)
NEXT
REPEAT UNTIL BUTTON(0) AND #B
DATA 0,0,0
DATA 255,0,0
DATA 0,255,0
DATA 0,0,255
DATA 255,0,255
DATA 0,255,255
DATA 255,255,0
DATA 255,255,255
TI Basic
100 REM SMPTE Format Color Bars
110 REM with 400 Hz reference tone
120 CALL CLEAR
130 CALL SCREEN(2)
140 CALL COLOR(8,15,1)
150 CALL COLOR(9,11,1)
160 CALL COLOR(10,8,1)
170 CALL COLOR(11,13,1)
180 CALL COLOR(12,14,1)
190 CALL COLOR(13,10,1)
200 CALL COLOR(14,5,1)
210 CALL COLOR(15,2,1)
220 CALL COLOR(16,16,1)
230 GOSUB 510
240 REM color bars
250 CALL VCHAR(1,3,88,96)
260 CALL VCHAR(1,7,96,96)
270 CALL VCHAR(1,11,104,96)
280 CALL VCHAR(1,15,112,96)
290 CALL VCHAR(1,19,120,96)
300 CALL VCHAR(1,23,128,96)
310 CALL VCHAR(1,27,136,96)
320 REM BLACK BAR
330 CALL HCHAR(19,1,144,224)
340 REM WHITE BOX
350 FOR I=19 TO 24
360 CALL HCHAR(I,8,152,6)
370 NEXT I
410 REM SMPTE Complementary boxes
420 CALL HCHAR(18,3,136,4)
430 CALL HCHAR(18,7,144,4)
440 CALL HCHAR(18,11,120,4)
450 CALL HCHAR(18,15,144,4)
460 CALL HCHAR(18,19,104,4)
470 CALL HCHAR(18,23,144,4)
480 CALL HCHAR(18,27,88,4)
490 CALL SOUND(3000,400,12)
500 GOTO 490
510 SQUARE$="FFFFFFFFFFFFFFFF"
520 FOR I = 88 TO 152 STEP 8
530 CALL CHAR(I,SQUARE$)
540 NEXT I
590 RETURN
ZX Spectrum Basic
10 REM The ZX Spectrum display is 32 columns wide, so we have 8 columns of 4 spaces
20 FOR r=0 TO 20: REM There are 21 rows
30 FOR c=0 TO 7: REM We use the native colour sequence here
40 PAPER c: REM set the background colour for the spaces to be printed
50 PRINT " ";: REM four spaces, the semicolon prevents newline
60 NEXT c
70 REM at this point the cursor has wrapped, so we don't need a newline
80 NEXT r
Befunge
Assuming a terminal with support for ANSI escape sequences, this fills the screen with the colour sequence: black, red, green, blue, magenta, cyan, yellow and white. It then waits for the user to press Enter before terminating.
<v%"P": <<*"(2"
v_:"P"/"["39*,, :55+/68v
v,,,";1H" ,+*86%+55 ,+*<
73654210v,,\,,,*93"[4m"<
>$:55+%#v_:1-"P"%55+/3g^
39*,,,~@>48*,1-:#v_$"m["
C
This task requires functionality which allows the code to communicate to the video device. This will vary from vendor to vendor. The following examples show two ways of doing this, in the text and graphics mode, using Borland's Turbo C.
Text Mode
The required functions and structures are in conio.h
#include<conio.h>
#define COLOURS 8
int main()
{
int colour=0,i,j,MAXROW,MAXCOL;
struct text_info tInfo;
gettextinfo(&tInfo);
MAXROW = tInfo.screenheight;
MAXCOL = tInfo.screenwidth;
textbackground(BLACK); //8 colour constants are defined
clrscr();
for(colour=0;colour<COLOURS;colour++)
{
getch(); //waits for a key hit
gotoxy(1+colour*MAXCOL/COLOURS,1);
textbackground(colour);
for(j=0;j<MAXROW;j++){
for(i=0;i<MAXCOL/COLOURS;i++){
cprintf(" ");
}
gotoxy(1+colour*MAXCOL/COLOURS,1+j);
}
}
getch();
textbackground(BLACK);
return 0;
}
Graphics Mode
The required functions and structures are in graphics.h, conio.h is included for getch().
#include<graphics.h>
#include<conio.h>
int main()
{
int d=DETECT,m,maxX,maxY,maxColours,i;
initgraph(&d,&m,"c:/turboc3/bgi");
maxX = getmaxx();
maxY = getmaxy();
maxColours = getmaxcolor();
for(i=0;i<maxColours;i++)
{
setfillstyle(SOLID_FILL,i);
bar(i*maxX/maxColours,0,(i+1)*maxX/maxColours,maxY);
}
getch();
closegraph();
return 0;
}
C++
using Qt 4.6
file colorbars.h
:
#ifndef MYWIDGET_H
#define MYWIDGET_H
#include <QWidget>
class QPaintEvent ;
class MyWidget : public QWidget {
public :
MyWidget( ) ;
protected :
void paintEvent( QPaintEvent * ) ;
private :
int width ;
int height ;
const int colornumber ;
} ;
#endif
file colorbars.cpp
:
#include <QtGui>
#include "colorbars.h"
MyWidget::MyWidget( ) :
width( 640 ) ,
height( 240 ) ,
colornumber( 8 ) {
setGeometry( 0, 0 , width , height ) ;
}
void MyWidget::paintEvent ( QPaintEvent * ) {
int rgbtriplets[ ] = { 0 , 0 , 0 , 255 , 0 , 0 , 0 , 255 , 0 ,
0 , 0 , 255 , 255 , 0 , 255 , 0 , 255 , 255 , 255 , 255 , 0 ,
255 , 255 , 255 } ;
QPainter myPaint( this ) ;
int rectwidth = width / colornumber ; //width of one rectangle
int xstart = 1 ; //x coordinate of the first rectangle
int offset = -1 ; //to allow for ++offset to define the red value even in the first run of the loop below
for ( int i = 0 ; i < colornumber ; i++ ) {
QColor rectColor ;
rectColor.setRed( rgbtriplets[ ++offset ] ) ;
rectColor.setGreen( rgbtriplets[ ++offset ] ) ;
rectColor.setBlue( rgbtriplets[ ++offset ] ) ;
myPaint.fillRect( xstart , 0 , rectwidth , height - 1 , rectColor ) ;
xstart += rectwidth + 1 ;
}
}
file main.cpp
:
#include <QApplication>
#include "colorbars.h"
int main( int argc, char * argv[ ] ) {
QApplication app( argc , argv ) ;
MyWidget window ;
window.setWindowTitle( QApplication::translate( "colorslides" , "color slides demonstration" ) ) ;
window.show( ) ;
return app.exec( ) ;
}
COBOL
IDENTIFICATION DIVISION.
PROGRAM-ID. terminal-colour-bars.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 width PIC 9(3).
01 height PIC 9(3).
01 interval PIC 9(3).
01 colours-area.
03 colour-values.
05 FILLER PIC 9 VALUE 0. *> Black
05 FILLER PIC 9 VALUE 4. *> Red
05 FILLER PIC 9 VALUE 2. *> Green
05 FILLER PIC 9 VALUE 1. *> Blue
05 FILLER PIC 9 VALUE 5. *> Magneta
05 FILLER PIC 9 VALUE 3. *> Cyan
05 FILLER PIC 9 VALUE 6. *> Yellow
05 FILLER PIC 9 VALUE 7. *> White
03 colour-table REDEFINES colour-values.
05 colours PIC 9 OCCURS 8 TIMES INDEXED BY colour-index.
01 i PIC 9(3).
01 j PIC 9(3).
PROCEDURE DIVISION.
ACCEPT width FROM COLUMNS
ACCEPT height FROM LINES
DIVIDE width BY 8 GIVING interval
PERFORM VARYING i FROM 1 BY 1 UNTIL height < i
PERFORM VARYING j FROM 1 BY 1 UNTIL width < j
COMPUTE colour-index = (j / interval) + 1
IF 8 < colour-index
SET colour-index TO 8
END-IF
*> Some colours come a bit darker than they
*> should, with the yellow being orange and the white
*> being light-grey.
DISPLAY SPACE AT LINE i COLUMN j
WITH BACKGROUND-COLOR colours (colour-index)
END-PERFORM
END-PERFORM
ACCEPT i *> Prevent ncurses returning to console immediately.
GOBACK
.
Common Lisp
ncurses
To interface the ncurses C library from Lisp, the croatoan library is used.
(defun color-bars ()
(with-screen (scr :input-blocking t :input-echoing nil :cursor-visible nil)
(dotimes (i (height scr))
(move scr i 0)
(dolist (color '(:red :green :yellow :blue :magenta :cyan :white :black))
(add-char scr #\space :bgcolor color :n (floor (/ (width scr) 8)))))
(refresh scr)
;; wait for keypress
(get-char scr)))
Delphi
unit Colour_barsDisplay;
interface
uses
Winapi.Windows, System.SysUtils, System.Classes, Vcl.Graphics, Vcl.Forms;
type
TfmColourBar = class(TForm)
procedure FormPaint(Sender: TObject);
procedure FormResize(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
fmColourBar: TfmColourBar;
Colors: array of TColor = [clblack, clred, clgreen, clblue, clFuchsia, clAqua,
clyellow, clwhite];
implementation
{$R *.dfm}
procedure TfmColourBar.FormPaint(Sender: TObject);
var
w, h, i: Integer;
r: TRect;
begin
w := ClientWidth div length(Colors);
h := ClientHeight;
r := Rect(0, 0, w, h);
with Canvas do
for i := 0 to High(Colors) do
begin
Brush.Color := Colors[i];
FillRect(r);
r.Offset(w, 0);
end;
end;
procedure TfmColourBar.FormResize(Sender: TObject);
begin
Invalidate;
end;
end.
Form resource:
object fmColourBar: TfmColourBar
Caption = 'fmColourBar'
OldCreateOrder = False
OnPaint = FormPaint
OnResize = FormResize
end
EasyLang
col[] = [ 000 900 090 009 909 099 990 999 ]
w = 100 / len col[]
for i = 1 to len col[]
color col[i]
move w * (i - 1) 0
rect w 100
.
Factor
USING: accessors colors.constants kernel math sequences ui
ui.gadgets ui.gadgets.tracks ui.pens.solid ;
IN: rosetta-code.colour-bars-display
: colors ( -- ) [
horizontal <track>
{
COLOR: black
COLOR: red
COLOR: green
COLOR: blue
COLOR: magenta
COLOR: cyan
COLOR: yellow
COLOR: white
}
[ <solid> gadget new swap >>interior ] map
dup length recip
[ track-add ] curry each
{ 640 480 } >>pref-dim
"bars" open-window
] with-ui ;
MAIN: colors
Forth
This program extends ANS Forth to control the TMS9918 Video display processor in the TI-99 computer.
The color bars are shown in Society of Motion Picture and Television Engineers (SMPTE) order.
\ Color Bars for TI-99 CAMEL99 Forth
NEEDS HCHAR FROM DSK1.GRAFIX \ TMS9918 control lexicon
NEEDS CHARSET FROM DSK1.CHARSET \ restores default character data
NEEDS ENUM FROM DSK1.ENUM \ add simple enumerator to Forth
\ Name TI-99 colors
1 ENUM CLR ENUM BLK ENUM MGRN ENUM LGRN
ENUM BLU ENUM LBLU ENUM RED ENUM CYAN
ENUM MRED ENUM LRED ENUM YEL ENUM LYEL
ENUM GRN ENUM MAG ENUM GRY ENUM WHT
DROP
\ square character data
HEX
CREATE SQUARE FFFF , FFFF , FFFF , FFFF ,
DECIMAL
: COLOR-BARS ( -- )
24 0 DO
\ col row char wid
\ --- --- ---- ---
2 I 88 4 HCHAR
6 I 96 4 HCHAR
10 I 104 4 HCHAR
14 I 112 4 HCHAR
18 I 120 4 HCHAR
22 I 128 4 HCHAR
26 I 136 4 HCHAR
LOOP ;
DECIMAL
: DEFCHARS ( pattern first last -- )
1+ SWAP ?DO DUP I CHARDEF 8 +LOOP DROP ;
: SET-COLORS ( -- )
\ charset fg bg
\ ------- -- --
88 SET# GRY CLR COLOR
96 SET# YEL CLR COLOR
104 SET# CYAN CLR COLOR
112 SET# GRN CLR COLOR
120 SET# MAG CLR COLOR
128 SET# RED CLR COLOR
136 SET# BLU CLR COLOR
144 SET# BLK CLR COLOR ;
\ restore characters and colors
: DEFAULTS
8 SCREEN
4 19 BLK CLR COLORS
CLEAR
CHARSET ;
: BARS
CLEAR BLK SCREEN
SET-COLORS
SQUARE 88 152 DEFCHARS
COLOR-BARS
BEGIN ?TERMINAL UNTIL
DEFAULTS
;
CR .( Done. Type BARS to run)
FutureBasic
void local fn DoIt
long index, x = 0
CFArrayRef colors = @[fn ColorBlack,fn ColorRed,
fn ColorGreen,fn ColorBlue,fn ColorMagenta,
fn ColorCyan,fn ColorYellow,fn ColorWhite]
window 1, @"Color bars/Display", (0,0,480,270), NSWindowStyleMaskTitled
pen -1
for index = 0 to len(colors) - 1
rect fill (x,0,60,270), colors[index]
x += 60
next
end fn
fn DoIt
HandleEvents
Go
package main
import "github.com/fogleman/gg"
var colors = [8]string{
"000000", // black
"FF0000", // red
"00FF00", // green
"0000FF", // blue
"FF00FF", // magenta
"00FFFF", // cyan
"FFFF00", // yellow
"FFFFFF", // white
}
func drawBars(dc *gg.Context) {
w := float64(dc.Width() / len(colors))
h := float64(dc.Height())
for i := range colors {
dc.SetHexColor(colors[i])
dc.DrawRectangle(w*float64(i), 0, w, h)
dc.Fill()
}
}
func main() {
dc := gg.NewContext(400, 400)
drawBars(dc)
dc.SavePNG("color_bars.png")
}
- Output:
Image similar to R entry.
Haskell
Terminal-based version.
#!/usr/bin/env stack
-- stack --resolver lts-7.0 --install-ghc runghc --package vty -- -threaded
import Graphics.Vty
colorBars :: Int -> [(Int, Attr)] -> Image
colorBars h bars = horizCat $ map colorBar bars
where colorBar (w, attr) = charFill attr ' ' w h
barWidths :: Int -> Int -> [Int]
barWidths nBars totalWidth = map barWidth [0..nBars-1]
where fracWidth = fromIntegral totalWidth / fromIntegral nBars
barWidth n =
let n' = fromIntegral n :: Double
in floor ((n' + 1) * fracWidth) - floor (n' * fracWidth)
barImage :: Int -> Int -> Image
barImage w h = colorBars h $ zip (barWidths nBars w) attrs
where attrs = map color2attr colors
nBars = length colors
colors = [black, brightRed, brightGreen, brightBlue, brightMagenta, brightCyan, brightYellow, brightWhite]
color2attr c = Attr Default Default (SetTo c)
main :: IO ()
main = do
cfg <- standardIOConfig
vty <- mkVty cfg
let output = outputIface vty
bounds <- displayBounds output
let showBars (w,h) = do
let img = barImage w h
pic = picForImage img
update vty pic
e <- nextEvent vty
case e of
EvResize w' h' -> showBars (w',h')
_ -> return ()
showBars bounds
shutdown vty
Graphical version using SFML.
-- Before you can install the SFML Haskell library, you need to install
-- the CSFML C library. (For example, "brew install csfml" on OS X.)
-- This program runs in fullscreen mode.
-- Press any key or mouse button to exit.
import Control.Exception
import SFML.Graphics
import SFML.SFResource
import SFML.Window hiding (width, height)
withResource :: SFResource a => IO a -> (a -> IO b) -> IO b
withResource acquire = bracket acquire destroy
withResources :: SFResource a => IO [a] -> ([a] -> IO b) -> IO b
withResources acquire = bracket acquire (mapM_ destroy)
colors :: [Color]
colors = [black, red, green, magenta, cyan, yellow, white]
makeBar :: (Float, Float) -> (Color, Int) -> IO RectangleShape
makeBar (barWidth, height) (c, i) = do
bar <- err $ createRectangleShape
setPosition bar $ Vec2f (fromIntegral i * barWidth) 0
setSize bar $ Vec2f barWidth height
setFillColor bar c
return bar
barSize :: VideoMode -> (Float, Float)
barSize (VideoMode w h _ ) = ( fromIntegral w / fromIntegral (length colors)
, fromIntegral h )
loop :: RenderWindow -> [RectangleShape] -> IO ()
loop wnd bars = do
mapM_ (\x -> drawRectangle wnd x Nothing) bars
display wnd
evt <- waitEvent wnd
case evt of
Nothing -> return ()
Just SFEvtClosed -> return ()
Just (SFEvtKeyPressed {}) -> return ()
Just (SFEvtMouseButtonPressed {}) -> return ()
_ -> loop wnd bars
main :: IO ()
main = do
vMode <- getDesktopMode
let wStyle = [SFFullscreen]
withResource (createRenderWindow vMode "color bars" wStyle Nothing) $
\wnd -> withResources (mapM (makeBar $ barSize vMode) $ zip colors [0..]) $
\bars -> loop wnd bars
Icon and Unicon
The procedure below is generalized to take a description of a test card and display it.
The following example is a wee tiny bit more interesting.
graphics.icn provides graphics printf.icn provides sprintf
J
load 'viewmat'
size=: 2{.".wd'qm' NB. J6
size=: getscreenwh_jgtk_ '' NB. J7
'rgb'viewmat (|.size){. (>.&.(%&160)|.size)$ 20# 256#.255*#:i.8
Note: You need to pick an implementation of size
based on the version of J you are using.
Java
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
public class ColorFrame extends JFrame {
public ColorFrame(int width, int height) {
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setSize(width, height);
this.setVisible(true);
}
@Override
public void paint(Graphics g) {
Color[] colors = { Color.black, Color.red, Color.green, Color.blue,
Color.pink, Color.CYAN, Color.yellow, Color.white };
for (int i = 0; i < colors.length; i++) {
g.setColor(colors[i]);
g.fillRect(this.getWidth() / colors.length * i, 0, this.getWidth()
/ colors.length, this.getHeight());
}
}
public static void main(String args[]) {
new ColorFrame(200, 200);
}
}
Julia
using Images
colors = [colorant"black", colorant"red", colorant"green", colorant"darkblue",
colorant"purple", colorant"blue", colorant"yellow", colorant"white"]
wcol = 60 # width of each color bar
h, w = 150, wcol * length(colors) + 1
img = Matrix{RGB{N0f8}}(h, w);
for (j, col) in zip(1:wcol:w, colors)
img[:, j:j+wcol] = col
end
save("data/colourbars.jpg", img)
Kotlin
import java.awt.Color
import java.awt.Graphics
import javax.swing.JFrame
class ColorFrame(width: Int, height: Int): JFrame() {
init {
defaultCloseOperation = EXIT_ON_CLOSE
setSize(width, height)
isVisible = true
}
override fun paint(g: Graphics) {
val colors = listOf(Color.black, Color.red, Color.green, Color.blue,
Color.pink, Color.cyan, Color.yellow, Color.white)
val size = colors.size
for (i in 0 until size) {
g.color = colors[i]
g.fillRect(width / size * i, 0, width / size, height)
}
}
}
fun main(args: Array<String>) {
ColorFrame(400, 400)
}
Editing Babbage problem
Lua
local nw = require("nw")
local app = nw:app()
local cw, ch = 320, 240
local win = app:window(cw, ch, "Color Bars", false)
local colors = {{0,0,0}, {1,0,0}, {0,1,0}, {0,0,1}, {1,0,1}, {0,1,1}, {1,1,0}, {1,1,1}}
local unpack = unpack or table.unpack -- polyfill 5.2 vs 5.3
function win:repaint()
local cr = win:bitmap():cairo()
for i = 1, #colors do
cr:rectangle((i-1)*cw/#colors, 0, cw/#colors, ch)
cr:rgb(unpack(colors[i]))
cr:fill()
end
end
win:show()
app:run()
M2000 Interpreter
Calling a module can be done by using name or call name. The later used for recursive call. Here we use it for beautify the code.
Module Checkit {
Module Bars {
barwidth=x.twips div 8
barheight=y.twips
barcolors=(0,#ff0000,#00ff00, #0000ff, #FF00FF, #00ffff, #ffff00, #ffffff)
For i=0 to 7
Move i*barwidth, 0
\\ gradient fill. Here second color are the same as first color
Fill barwidth, barheight, array(barcolors, i), array(barcolors, i)
Next i
}
\\ first draw on console
Call Bars
Declare Form1 Form
Layer Form1 {
window 12, 10000,8000;
\\ now draw on Form1 layer, above console, in a window
Call Bars
}
Method Form1, "Show", 1 ' open modal
Declare Form1 Nothing
}
Checkit
Maple
with(plottools):
plots:-display([rectangle([0, 0], [.3, 2.1], color = black), rectangle([.3, 0], [.6, 2.1], color = red), rectangle([.6, 0], [.9, 2.1], color = green), rectangle([.9, 0], [1.2, 2.1], color = magenta), rectangle([1.2, 0], [1.5, 2.1], color = cyan), rectangle([1.5, 0], [1.8, 2.1], color = white), rectangle([1.8, 0], [2.1, 2.1], color = yellow)])
Mathematica / Wolfram Language
ArrayPlot[
ConstantArray[{Black, Red, Green, Blue, Magenta, Cyan, Yellow,
White}, 5]]
Nim
import gintro/[glib, gobject, gtk, gio, cairo]
const
Width = 400
Height = 300
#---------------------------------------------------------------------------------------------------
proc draw(area: DrawingArea; context: Context) =
## Draw the color bars.
const Colors = [[0.0, 0.0, 0.0], [255.0, 0.0, 0.0],
[0.0, 255.0, 0.0], [0.0, 0.0, 255.0],
[255.0, 0.0, 255.0], [0.0, 255.0, 255.0],
[255.0, 255.0, 0.0], [255.0, 255.0, 255.0]]
const
RectWidth = float(Width div Colors.len)
RectHeight = float(Height)
var x = 0.0
for color in Colors:
context.rectangle(x, 0, RectWidth, RectHeight)
context.setSource(color)
context.fill()
x += RectWidth
#---------------------------------------------------------------------------------------------------
proc onDraw(area: DrawingArea; context: Context; data: pointer): bool =
## Callback to draw/redraw the drawing area contents.
area.draw(context)
result = true
#---------------------------------------------------------------------------------------------------
proc activate(app: Application) =
## Activate the application.
let window = app.newApplicationWindow()
window.setSizeRequest(Width, Height)
window.setTitle("Color bars")
# Create the drawing area.
let area = newDrawingArea()
window.add(area)
# Connect the "draw" event to the callback to draw the spiral.
discard area.connect("draw", ondraw, pointer(nil))
window.showAll()
#———————————————————————————————————————————————————————————————————————————————————————————————————
let app = newApplication(Application, "Rosetta.ColorBars")
discard app.connect("activate", activate)
discard app.run()
OCaml
open Graphics
let round x =
int_of_float (floor (x +. 0.5))
let () =
open_graph "";
let cols = size_x () in
let rows = size_y () in
let colors = [| black; red; green; blue; magenta; cyan; yellow; white |] in
let n = Array.length colors in
let bar_width = (float cols) /. (float n) in
Array.iteri (fun i color ->
let x1 = bar_width *. (float i) in
let x2 = bar_width *. (float (succ i)) in
set_color color;
fill_rect (round x1) 0 (round x2) rows;
) colors;
ignore (read_key ());
;;
execute with:
$ ocaml graphics.cma display_colour_bars.ml
PascalABC.NET
##
uses GraphABC;
Window.title := 'Color bars';
var colors := |clblack, clred, clgreen, clblue, clmagenta, clcyan, clyellow, clwhite|;
var w := Window.Width div colors.Count;
var h := Window.Height;
for var i := 0 to colors.Count - 1 do
begin
Brush.Color := colors[i];
FillRectangle(w * i, 0, w * i + w, h);
end;
Perl
use strict;
use warnings;
use GD;
my %colors = (
white => [255,255,255], red => [255, 0, 0], green => [ 0,255, 0], blue => [ 0, 0,255],
magenta => [255, 0,255], yellow => [255,255, 0], cyan => [ 0,255,255], black => [ 0, 0, 0]);
my $start = 0;
my $barwidth = 160 / 8;
my $image = GD::Image->new( 160 , 100 );
for my $rgb ( values %colors ) {
$image->filledRectangle( $start * $barwidth , 0 , $start * $barwidth +
$barwidth - 1 , 99 , $image->colorAllocate( @$rgb ) );
$start++ ;
}
open ( DISPLAY , ">" , "bars.png" ) or die;
binmode DISPLAY;
print DISPLAY $image->png;
close DISPLAY;
Phix
-- demo\rosetta\Colour_bars.exw with javascript_semantics include pGUI.e constant colours = {CD_BLACK, CD_RED, CD_GREEN, CD_BLUE, CD_MAGENTA, CD_CYAN, CD_YELLOW, CD_WHITE} Ihandle dlg, canvas cdCanvas cdcanvas function redraw_cb(Ihandle /*ih*/, integer /*posx*/, /*posy*/) integer {width, height} = IupGetIntInt(canvas, "DRAWSIZE"), x = 0, lc = length(colours) cdCanvasActivate(cdcanvas) for i=1 to lc do integer w = floor((width-x)/(lc-i+1)) cdCanvasSetForeground(cdcanvas, colours[i]) cdCanvasBox(cdcanvas, x, x+w, 0, height) x += w end for cdCanvasFlush(cdcanvas) return IUP_DEFAULT end function IupOpen() canvas = IupCanvas(Icallback("redraw_cb"),"RASTERSIZE=600x400") -- initial size dlg = IupDialog(canvas,`TITLE="Colour bars"`) IupMap(dlg) cdcanvas = cdCreateCanvas(CD_IUP, canvas) IupShow(dlg) IupSetAttribute(canvas, "RASTERSIZE", NULL) -- release the minimum limitation if platform()!=JS then IupMainLoop() IupClose() end if
PHP
Will output result directly to the browser. Use it as CGI/BIN script.
<?php
$colors = array(array( 0, 0, 0), // black
array(255, 0, 0), // red
array( 0, 255, 0), // green
array( 0, 0, 255), // blue
array(255, 0, 255), // magenta
array( 0, 255, 255), // cyan
array(255, 255, 0), // yellow
array(255, 255, 255)); // white
define('BARWIDTH', 640 / count($colors));
define('HEIGHT', 480);
$image = imagecreate(BARWIDTH * count($colors), HEIGHT);
foreach ($colors as $position => $color) {
$color = imagecolorallocate($image, $color[0], $color[1], $color[2]);
imagefilledrectangle($image, $position * BARWIDTH, 0,
$position * BARWIDTH + BARWIDTH - 1,
HEIGHT - 1, $color);
}
header('Content-type:image/png');
imagepng($image);
imagedestroy($image);
Alternately, with HTML output:
<?php
$colors = array(
"000000", // black
"FF0000", // red
"00FF00", // green
"0000FF", // blue
"FF00FF", // magenta
"00FFFF", // cyan
"FFFF00", // yellow
"FFFFFF", // white
);
echo '<table style="border: 1px solid black; border-spacing: 0;"><tr>';
foreach ($colors as $color) {
echo '<td style="background-color: #'.$color.'; height: 100px; width: 20px;"></td>';
}
echo '</tr></table>';
PicoLisp
(call 'clear)
(let Width (in '(tput cols) (read))
(do (in '(tput lines) (read))
(for B (range 0 7)
(call 'tput 'setab B)
(space (/ Width 8)) )
(prinl) ) )
(call 'tput 'sgr0) # reset
Plain English
To run:
Start up.
Clear the screen.
Divide the screen width by 8 giving a bar width.
Make a bar with 0 and 0 and the bar width and the screen's bottom.
Draw the color bars using the bar.
Refresh the screen.
Wait for the escape key.
Shut down.
To divide the screen width by a number giving a width:
Put the screen's right into the width.
Divide the width by the number.
A bar is a box.
To draw a bar using a color and move it over:
Draw and fill the bar with the color.
Move the bar right the bar's width.
To draw the color bars using a bar:
Draw the bar using the black color and move it over.
Draw the bar using the red color and move it over.
Draw the bar using the green color and move it over.
Draw the bar using the blue color and move it over.
Draw the bar using the magenta color and move it over.
Draw the bar using the cyan color and move it over.
Draw the bar using the yellow color and move it over.
Draw and fill the bar using the white color.
PowerShell
[string[]]$colors = "Black" , "DarkBlue" , "DarkGreen" , "DarkCyan",
"DarkRed" , "DarkMagenta", "DarkYellow", "Gray",
"DarkGray", "Blue" , "Green" , "Cyan",
"Red" , "Magenta" , "Yellow" , "White"
for ($i = 0; $i -lt 64; $i++)
{
for ($j = 0; $j -lt $colors.Count; $j++)
{
Write-Host (" " * 12) -BackgroundColor $colors[$j] -NoNewline
}
Write-Host
}
Processing
fullScreen();
noStroke();
color[] cs = {
color(0), // black
color(255,0,0), // red
color(0,255,0), // green
color(255,0,255), // magenta
color(0,255,255), // cyan
color(255,255,0), // yellow
color(255) // white
};
for(int i=0; i<7; i++) {
fill(cs[i]);
rect(i*width/8,0,width/8,height);
}
Python
#!/usr/bin/env python
#vertical coloured stripes in window in Python 2.7.1
from livewires import *
horiz=640; vert=480
begin_graphics(width=horiz,height=vert,title="v_stripes",background=Colour.black)
NameColors=["black","red","green","dark_blue","purple","blue","yellow","white"]
stepik=horiz/len(NameColors)
for index,each in enumerate(NameColors):
ExcStrng="set_colour(Colour."+each+")"
exec ExcStrng
box(index*stepik,0,(index+1)*stepik,vert,filled=1)
while keys_pressed() != ['x']: # press x key to terminate program
pass
end_graphics()
R
Create the color palette, set margins to zero so the image will fill the display, and use image to create the graphic:
pal <- c("black", "red", "green", "blue", "magenta", "cyan", "yellow", "white")
par(mar = rep(0, 4))
image(matrix(1:8), col = pal, axes = FALSE)
Racket
#lang racket/gui
(define-values [W H] (get-display-size #t))
(define colors
'("Black" "Red" "Green" "Blue" "Magenta" "Cyan" "Yellow" "White"))
(define (paint-pinstripe canvas dc)
(send dc set-pen "black" 0 'transparent)
(for ([x (in-range 0 W (/ W (length colors)))] [c colors])
(send* dc (set-brush c 'solid) (draw-rectangle x 0 W H))))
(define full-frame%
(class frame%
(define/override (on-subwindow-char r e)
(when (eq? 'escape (send e get-key-code))
(send this show #f)))
(super-new
[label "Color bars"] [width W] [height H]
[style '(no-caption no-resize-border hide-menu-bar no-system-menu)])
(define c (new canvas% [parent this] [paint-callback paint-pinstripe]))
(send this show #t)))
(void (new full-frame%))
Raku
(formerly Perl 6)
my ($x,$y) = 1280, 720;
my @colors = map -> $r, $g, $b { Buf.new: |(($r, $g, $b) xx $x div 8) },
0, 0, 0,
255, 0, 0,
0, 255, 0,
0, 0, 255,
255, 0, 255,
0, 255, 255,
255, 255, 0,
255, 255, 255;
my $img = open "colorbars.ppm", :w orelse die "Can't create colorbars.ppm: $_";
$img.print: qq:to/EOH/;
P6
# colorbars.ppm
$x $y
255
EOH
for ^$y {
for ^@colors -> $h {
$img.write: @colors[$h];
}
}
$img.close;
REXX
Programming note: because of the way the REXX interpreters (being used for this example) ensure screen output fidelity, if ninety characters are displayed on a ninety-byte wide screen, REXX apparently forces an extra blank, causing to what appears to be a blank line after the line displayed. Because of this, the last color bar (_.8) has been shortened by one byte.
/*REXX program displays eight colored vertical bars on a full screen. */
parse value scrsize() with sd sw . /*the screen depth and width. */
barWidth=sw%8 /*calculate the bar width. */
_.=copies('db'x, barWidth) /*the bar, full width. */
_.8=left(_.,barWidth-1) /*the last bar width, less one. */
$ = x2c('1b5b73') || x2c("1b5b313b33376d") /* the preamble, and the header. */
hdr.1 = x2c('1b5b303b33306d') /* " color black. */
hdr.2 = x2c('1b5b313b33316d') /* " color red. */
hdr.3 = x2c('1b5b313b33326d') /* " color green. */
hdr.4 = x2c('1b5b313b33346d') /* " color blue. */
hdr.5 = x2c('1b5b313b33356d') /* " color magenta. */
hdr.6 = x2c('1b5b313b33366d') /* " color cyan. */
hdr.7 = x2c('1b5b313b33336d') /* " color yellow. */
hdr.8 = x2c('1b5b313b33376d') /* " color white. */
tail = x2c('1b5b751b5b303b313b33363b34303b306d') /* " epilogue, and the trailer.*/
/* [↓] last bar width is shrunk. */
do j=1 for 8 /*build the line, color by color. */
$=$ || hdr.j || _.j /*append the color header + bar. */
end /*j*/ /* [↑] color order is the list. */
/* [↓] the tail is overkill. */
$=$ || tail /*append the epilogue (trailer). */
/* [↓] show full screen of bars. */
do k=1 for sd /*SD = screen depth (from above). */
say $ /*have REXX display line of bars. */
end /*k*/ /* [↑] Note: SD could be zero. */
/*stick a fork in it, we're done. */
This REXX program makes use of scrsize REXX program (or BIF) which is used to determine the screen size of the terminal (console).
The SCRSIZE.REX REXX program is included here ──► SCRSIZE.REX.
output appears identical to the output for Icon and Unicon, Mathematica, and R examples.
Ring
load "guilib.ring"
new qapp
{
win1 = new qwidget() {
setwindowtitle("drawing using qpainter")
setwinicon(self,"C:\Ring\bin\image\browser.png")
setgeometry(100,100,500,600)
label1 = new qlabel(win1) {
setgeometry(10,10,400,400)
settext("")
}
new qpushbutton(win1) {
setgeometry(200,400,100,30)
settext("draw")
setclickevent("draw()")
}
show()
}
exec()
}
func draw
p1 = new qpicture()
color = new qcolor() {
setrgb(0,0,255,255)
}
pen = new qpen() {
setcolor(color)
setwidth(1)
}
new qpainter() {
begin(p1)
setpen(pen)
//Black, Red, Green, Blue, Magenta, Cyan, Yellow, White
for n = 1 to 8
color2 = new qcolor(){
switch n
on 1 r=0 g=0 b=0
on 2 r=255 g=0 b=0
on 3 r=0 g=255 b=0
on 4 r=0 g=0 b=255
on 5 r=255 g=0 b=255
on 6 r=0 g=255 b=255
on 7 r=255 g=255 b=0
on 8 r=255 g=255 b=255
off
setrgb(r,g,b,255)
}
mybrush = new qbrush() {setstyle(1) setcolor(color2)}
setbrush(mybrush)
drawrect(n*25,25,25,70)
next
endpaint()
}
label1 { setpicture(p1) show() }
Output : Colour bars
Ruby
JRubyArt is a port of Processing to the ruby language
# Array of web colors black, red, green, blue, magenta, cyan, yellow, white
PALETTE = %w[#000000 #ff0000 #00ff00 #0000ff #ff00ff #00ffff #ffffff].freeze
def settings
full_screen
end
def setup
PALETTE.each_with_index do |col, idx|
fill color(col)
rect(idx * width / 8, 0, width / 8, height)
end
end
Rust
renders into a borderless fullscreen window on the primary display. press ESC to close
use pixels::{Pixels, SurfaceTexture}; // 0.2.0
use winit::event::*; // 0.24.0
use winit::event_loop::{ControlFlow, EventLoop};
use winit::window::{Fullscreen, WindowBuilder};
fn main() {
let event_loop = EventLoop::new();
let window = WindowBuilder::new()
.with_title("Colour Bars")
.with_decorations(false)
.with_fullscreen(Some(Fullscreen::Borderless(None)))
.build(&event_loop).unwrap();
let size = window.inner_size();
let texture = SurfaceTexture::new(size.width, size.height, &window);
let mut image_buffer = Pixels::new(8, 1, texture).unwrap();
let frame = image_buffer.get_frame();
frame.copy_from_slice(&[
0x00, 0x00, 0x00, 0xFF, // black
0xFF, 0x00, 0x00, 0xFF, // red
0x00, 0xFF, 0x00, 0xFF, // green
0x00, 0x00, 0xFF, 0xFF, // blue
0xFF, 0x00, 0xFF, 0xFF, // magenta
0x00, 0xFF, 0xFF, 0xFF, // cyan
0xFF, 0xFF, 0x00, 0xFF, // yellow
0xFF, 0xFF, 0xFF, 0xFF, // white
]);
image_buffer.render().unwrap();
event_loop.run(move |ev, _, flow| {
match ev {
Event::WindowEvent {
event: WindowEvent::KeyboardInput { input, .. }, ..
} => {
if input.virtual_keycode == Some(VirtualKeyCode::Escape) {
*flow = ControlFlow::Exit;
}
}
Event::RedrawRequested(_) | Event::WindowEvent {
event: WindowEvent::Focused(true), ..
} => {
image_buffer.render().unwrap();
}
_ => {}
}
});
}
Scala
import java.awt.Color
import scala.swing._
class ColorBars extends Component {
override def paintComponent(g:Graphics2D)={
val colors=List(Color.BLACK, Color.RED, Color.GREEN, Color.BLUE, Color.MAGENTA, Color.CYAN, Color.YELLOW, Color.WHITE)
val colCount=colors.size
val deltaX=size.width.toDouble/colCount
for(x <- 0 until colCount){
val startX=(deltaX*x).toInt
val endX=(deltaX*(x+1)).toInt
g.setColor(colors(x))
g.fillRect(startX, 0, endX-startX, size.height)
}
}
}
Open window:
new MainFrame(){
title="Color bars"
visible=true
preferredSize=new Dimension(640, 320)
contents=new ColorBars()
}
Sidef
require('GD');
var colors = Hash.new(
white => [255, 255, 255],
red => [255, 0, 0],
green => [0, 255, 0],
blue => [0, 0, 255],
magenta => [255, 0, 255],
yellow => [255, 255, 0],
cyan => [0, 255, 255],
black => [0, 0, 0],
);
var barwidth = 160/8;
var image = %s'GD::Image'.new(160, 100);
var start = 0;
colors.values.each { |rgb|
var paintcolor = image.colorAllocate(rgb...);
image.filledRectangle(start * barwidth, 0, start*barwidth + barwidth - 1, 99, paintcolor);
start++;
};
%f'colorbars.png'.open('>:raw').print(image.png);
Tcl
package require Tcl 8.5
package require Tk 8.5
wm attributes . -fullscreen 1
pack [canvas .c -highlightthick 0] -fill both -expand 1
set colors {black red green blue magenta cyan yellow white}
for {set x 0} {$x < [winfo screenwidth .c]} {incr x 8} {
.c create rectangle $x 0 [expr {$x+7}] [winfo screenheight .c] \
-fill [lindex $colors 0] -outline {}
set colors [list {*}[lrange $colors 1 end] [lindex $colors 0]]
}
UNIX Shell
#!/bin/sh
clear
WIDTH=`tput cols`
HEIGHT=`tput lines`
NUMBARS=8
BARWIDTH=`expr $WIDTH / $NUMBARS`
l="1" # Set the line counter to 1
while [ "$l" -lt $HEIGHT ]; do
b="0" # Bar counter
while [ "$b" -lt $NUMBARS ]; do
tput setab $b
s="0"
while [ "$s" -lt $BARWIDTH ]; do
echo -n " "
s=`expr $s + 1`
done
b=`expr $b + 1`
done
echo # newline
l=`expr $l + 1`
done
tput sgr0 # reset
Uxntal
( uxnasm color-bars.tal color-bars.rom && uxnemu color-bars.rom )
|00 @System &vector $2 &expansion $2 &wst $1 &rst $1 &metadata $2 &r $2 &g $2 &b $2 &debug $1 &state $1
|20 @Screen &vector $2 &width $2 &height $2 &auto $1 &pad $1 &x $2 &y $2 &addr $2 &pixel $1 &sprite $1
|0100
( set 4 color theme
rgb
color0: 000 - black
color1: f00 - red
color2: 0f0 - green
color3: 00f - blue )
#0f00 .System/r DEO2
#00f0 .System/g DEO2
#000f .System/b DEO2
( store bars width )
.Screen/width DEI2 #0004 DIV2 ,&quarter STR2
( set starting position )
#0000 .Screen/y DEO2
( draw bars )
#00
&loop
#00 OVR [ LIT2 &quarter $2 ] MUL2
.Screen/x DEO2
DUP #80 ORA .Screen/pixel DEO
INC DUP #04 NEQ ?&loop
BRK
Wren
import "graphics" for Canvas, Color
import "dome" for Window
class Game {
static init() {
Window.title = "Color bars"
__width = 400
__height = 400
Canvas.resize(__width, __height)
Window.resize(__width, __height)
var colors = [
Color.hex("000000"), // black
Color.hex("FF0000"), // red
Color.hex("00FF00"), // green
Color.hex("0000FF"), // blue
Color.hex("FF00FF"), // magenta
Color.hex("00FFFF"), // cyan
Color.hex("FFFF00"), // yellow
Color.hex("FFFFFF") // white
]
drawBars(colors)
}
static drawBars(colors) {
var w = __width / colors.count
var h = __height
for (i in 0...colors.count) {
Canvas.rectfill(w*i, 0, w, h, colors[i])
}
}
static update() {}
static draw(dt) {}
}
XPL0
include c:\cxpl\codes; \intrinsic code declarations
int W, X0, X1, Y, C;
[SetVid($13); \320x200x8 graphics
W:= 320/8; \width of color bar (pixels)
for C:= 0 to 8-1 do
[X0:= W*C; X1:= X0+W-1;
for Y:= 0 to 200-1 do
[Move(X0, Y); Line(X1, Y, C)];
];
C:= ChIn(1); \wait for keystroke
SetVid(3); \restore normal text mode
]
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