I'm working on modernizing Rosetta Code's infrastructure. Starting with communications. Please accept this time-limited open invite to RC's Slack.. --Michael Mol (talk) 20:59, 30 May 2020 (UTC)

Joystick position

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

The task is to determine the joystick position and represent this on the display via a crosshair. For a centred joystick, the crosshair should appear in the centre of the screen. If the joystick is pushed left or right, then the cross hair should move left or right according to the extent that the joystick is pushed.

If the joystick is pushed forward or pulled back, then the crosshair should move up or down according to the extent that that joystick is pushed or pulled. The edges of the display represent maximum extents for joystick movement.

For example, a joystick pushed fully forward would raise the crosshair to the top centre of the screen.

A joystick pulled backwards and to the right would move the crosshair to the bottom right of the screen (except for a small area reserved to show joystick status). Implementations can use a graphical display method to produce the crosshair, or alternatively represent the crosshair using a plus symbol on a terminal, and move the plus symbol position according to the joystick. The bottom part of the display can hide or show an alphanumeric sequence to represent the buttons pressed.

For example, if pushbuttons 1,4 and 10 are depressed, we could display "1 4 A".

The implemented code should continue to redraw the crosshair according to the joystick position and show the current pushbutton statuses until the task is terminated. Digital joysticks that produce no extent data, should have their position indicated as full extent movement of the crosshair.

For the purpose of this task, we assume that the joystick is calibrated and that the first joystick is being used.
The task implementer could at their option provide a solution that includes a joystick selection facility, enabling the user to choose which joystick is to be used for this task.

Action![edit]

BYTE lastStick=[255]
BYTE lastTrig=[255]
 
PROC DrawCross(BYTE s)
BYTE size=[5]
CARD x
BYTE y
 
IF s>=9 AND s<=11 THEN
x=size
ELSEIF s>=5 AND s<=7 THEN
x=159-size
ELSE
x=79
FI
 
IF s=6 OR s=10 OR s=14 THEN
y=size
ELSEIF s=5 OR s=9 OR s=13 THEN
y=79-size
ELSE
y=39
FI
 
Plot(x-size,y)
DrawTo(x+size,y)
Plot(x,y-size)
DrawTo(x,y+size)
RETURN
 
PROC UpdateStatus(BYTE currStick,currTrig)
IF currStick#lastStick THEN
Color=0 DrawCross(lastStick)
Color=1 DrawCross(currStick)
lastStick=currStick
FI
 
IF currTrig#lastTrig THEN
Print("Button pressed: ")
IF currTrig THEN
PrintE("no ")
ELSE
PrintE("yes")
FI
Put(28) ;move cursor up
lastTrig=currTrig
FI
RETURN
 
PROC Main()
BYTE CH=$02FC,COLOR1=$02C5,COLOR2=$02C6,
CRSINH=$02F0 ;Controls visibility of cursor
BYTE currStick,currTrig
 
Graphics(7)
Color=1
COLOR1=$0C
COLOR2=$02
CRSINH=1 ;hide cursor
 
DO
currStick=Stick(0)
currTrig=STrig(0)
UpdateStatus(currStick,currTrig)
UNTIL CH#$FF
OD
CH=$FF
RETURN
Output:

Screenshot from Atari 8-bit computer

Applesoft BASIC[edit]

100 GOSUB 400
110 P2 = PDL(2) : IF P2 <> O2 THEN O2 = P2 : VTAB 23 : HTAB 33 : PRINT P2; TAB(37);
120 B2 = FNB(2) : IF B2 <> N2 THEN N2 = B2 : VTAB 24 : HTAB 15 : PRINT P$(B2);
130 P3 = PDL(3) : IF P3 <> O3 THEN O3 = P3 : VTAB 23 : HTAB 37 : PRINT P3; : CALL -868
140 X = INT(P3 * RX) : Y = INT(P2 * RY(F))
150 O = (X1 = X2 AND Y1 = Y2) + 1
160 N = (X = X1 AND Y = Y1) + 1
170 IF X <> X2 OR Y <> Y2 THEN XDRAW N AT X, Y : XDRAW O AT X2, Y2 : X2 = X : Y2 = Y : O = N
200 P0 = PDL(0) : IF P0 <> O0 THEN O0 = P0 : VTAB 22 : HTAB 33 : PRINT P0; TAB(37);
210 B0 = FNB(0) : IF B0 <> N0 THEN N0 = B0 : VTAB 22 : HTAB 15 : PRINT P$(B0);
220 P1 = PDL(1) : IF P1 <> O1 THEN O1 = P1 : VTAB 22 : HTAB 37 : PRINT P1; : CALL -868
230 B1 = FNB(1) : IF B1 <> N1 THEN N1 = B1 : VTAB 23 : HTAB 15 : PRINT P$(B1);
240 X = INT(P0 * RX) : Y = INT(P1 * RY(F))
250 O = (X1 = X2 AND Y1 = Y2) + 1
260 N = (X = X2 AND Y = Y2) + 1
270 IF X <> X1 OR Y <> Y1 THEN XDRAW N AT X, Y : XDRAW O AT X1, Y1 : X1 = X : Y1 = Y
300 K = PEEK(-16384) : IF K < 128 THEN 110
310 POKE-16368,0
320 IF K = 198 OR K = 200 THEN F = PEEK(-16302) ^ 0 : GOTO 110HIDE
330 IF K = 155 OR K = 211 THEN F = PEEK(-16301) * 0 : GOTO 110SHOW
340 TEXT : END
400 HOME : HGR
410 DEF FN B(B) = PEEK(49249 + B) > 127
420 P$(0) = "NOT PRESSED" : P$(1) = "PRESSED "
430 VTAB 21 : PRINT "BUTTON:";
440 PRINT TAB(28); "JOYSTICK:"
450 PRINT " OPEN APPLE "P$(0);
460 PRINT TAB(29); "ONE"
470 PRINT " CLOSED APPLE "P$(0);
480 PRINT TAB(29); "TWO"
490 PRINT TAB(9); "SHIFT "P$(0);
500 RX = 35 / 32 : RY(0) = 5 / 8 : RY(1) = 3 / 4
510 DATA2,0,6,0,3,0,29,15,20,6,0
520 FOR I = 768 TO 778 : READ B
530 POKE I, B : NEXT : POKE 232, 0 : POKE 233, 3
550 ROT = 0 : SCALE = 7 : XDRAW 1 AT X1, Y1
560 O0 = -1 : O1 = O0 : O2 = O0 : O3 = O0
570 RETURN

AutoHotkey[edit]

Works with: AutoHotkey_L
Library: GDIP

Forum thread

Image link

; Uncomment if Gdip.ahk is not in your standard library
; #Include, Gdip.ahk
 
; Comment for lower CPU usage
SetBatchLines, -1
 
JoystickNumber := 0 ; (1-16) or (0 = Auto-detect)
CrosshairSize := 100
BarWidth := 50
BarSpacing := BarWidth + 8
Color1 := 0x99000000
Color2 := 0x99ffffff
Color3 := 0x99ff6600
Color4 := 0xff0066ff
Color5 := 0xffff6600
Font := "Arial"
FontSize1 := 20
FontSize2 := 30
Lineweight1 := 8
Lineweight2 := 3
Lineweight3 := 2
Lineweight4 := 4
Show2ndCrosshair := true
AxisLabelHeight := 47
 
#SingleInstance, Force
#NoEnv
OnExit, Exit
SysGet, MWA, MonitorWorkArea
CrosshairOffset := CrosshairSize // 2
, CircleOffset := CrosshairOffset - 5
, CircleSize := CrosshairSize - 10
, TaskBarHeight := A_ScreenHeight - MWABottom + Lineweight1 // 2
, ScaleX := A_ScreenWidth / 100
, ScaleY1 := (A_ScreenHeight - TaskBarHeight - AxisLabelHeight) / 100
, ScaleY2 := A_ScreenHeight / 100
, BarCenter := (MWABottom - AxisLabelHeight) // 2 + AxisLabelHeight
, BorderBot := MWABottom - Lineweight1 // 2 + 2
, PieSize := 400
, PieX := (A_ScreenWidth - PieSize) // 2
, PieY := (A_ScreenHeight - PieSize) // 2
, BarHeight := A_ScreenHeight - AxisLabelHeight - TaskBarHeight
, AxisTextOffset := BarWidth > 32 ? (BarWidth - 32) // 2 : 0
, Axis_Array := {"X": "X", "Y": "Y"}
, MaxI := 2
 
; Auto-detect the joystick number if called for
if (JoystickNumber < 1) {
Loop, 16 {
GetKeyState, Joy_Name, %A_Index%JoyName
if (Joy_Name) {
JoystickNumber := A_Index
break
}
}
if (!JoystickNumber) {
MsgBox The system does not appear to have any joysticks.
ExitApp
}
}
else {
GetKeyState, Joy_Name, %JoystickNumber%JoyName
if (!Joy_Name) {
MsgBox The system does not appear to have a joystick number %JoystickNumber%.
ExitApp
}
}
 
if (!pToken := Gdip_Startup()) {
MsgBox, 48, Gdiplus error!, Gdiplus failed to start. Please ensure you have Gdiplus on your system.
ExitApp
}
 
If (!Gdip_FontFamilyCreate(Font)) {
MsgBox, 48, Font error!, The font you have specified does not exist on your system.
ExitApp
}
 
; Get joystick information
SetFormat, FloatFast, 03.2
GetKeyState, Joy_Buttons, % JoystickNumber "JoyButtons"
GetKeyState, Joy_Info, % JoystickNumber "JoyInfo"
Loop, Parse, Joy_Info
if (A_LoopField != "C" && A_LoopField != "D" && A_LoopField != "P")
Axis_Array[A_LoopField] := A_LoopField
, %A_LoopField% := true
, MaxI++
else
%A_LoopField% := true
 
; Setup Gdip
Gui, 1: -Caption +E0x80000 +LastFound +AlwaysOnTop +ToolWindow +OwnDialogs
Gui, 1: Show, NA
hwnd1 := WinExist()
, hbm := CreateDIBSection(A_ScreenWidth, A_ScreenHeight)
, hdc := CreateCompatibleDC()
, obm := SelectObject(hdc, hbm)
, G1 := Gdip_GraphicsFromHDC(hdc)
, Gdip_SetSmoothingMode(G1, 4)
, pPen1 := Gdip_CreatePen(Color1, Lineweight1)
, pPen2 := Gdip_CreatePen(Color2, Lineweight2)
, pPen3 := Gdip_CreatePen(Color4, Lineweight3)
, pPen4 := Gdip_CreatePen(Color5, Lineweight4)
, pBrush1 := Gdip_BrushCreateSolid(Color1)
, pBrush2 := Gdip_BrushCreateSolid(Color3)
 
; Crosshair 2
if ((R || U) && Show2ndCrosshair) {
pPen5 := Gdip_CreatePen(Color5, Lineweight3)
, pPen6 := Gdip_CreatePen(Color4, Lineweight4)
, joy_r := joy_u := 50
}
 
; Bar X-offsets
for key, val in Axis_Array
%val%X := A_ScreenWidth - MaxI * BarSpacing + BarSpacing * (A_Index - 1) + 3
 
; Info box
IBH1 := 150
, IBW1 := 450
, IBX1 := A_ScreenWidth - MaxI * BarSpacing - IBW1
, IBY1 := A_ScreenHeight - TaskBarHeight - IBH1 + Lineweight1 // 2
, IBH2 := IBH1 - 8
, IBW2 := IBW1 - 8
, IBX2 := IBX1 + 4
, IBY2 := IBY1 + 4
, FontOptions1 := "x" (IBX1 + 8) " y" (IBY1 + 8) " w" IBW1 - 20 " Left c" SubStr(Color2, 3) " r4 s" FontSize1 " Bold"
 
; Axis box
ABH1 := AxisLabelHeight + 4
, ABW1 := MaxI * BarSpacing
, ABX1 := A_ScreenWidth - MaxI * BarSpacing
, ABY1 := 0
, ABH2 := ABH1 - 16
, ABW2 := ABW1 - 8
, ABX2 := ABX1 + 4
, ABY2 := ABY1 + 4
, FontOptions2 := " y" ABY1 + AxisLabelHeight - 40 " w" ABW1 - 10 " Left c" SubStr(Color2, 3) " r4 s" FontSize2 " Bold"
 
; Update graphics
Loop, {
Buttons_Down := ""
Loop, %Joy_Buttons% {
GetKeyState, joy%A_Index%, %JoystickNumber%joy%A_Index%
if (joy%A_Index% = "D")
Buttons_Down .= " " A_Index
}
 
; Info & axis boxes
InfoText := Joy_Name " (#" JoystickNumber "):`n" Axis_Info "`nButtons Down: " Buttons_Down "`n`n(Ctrl+Esc to exit)"
, Gdip_FillRoundedRectangle(G1, pBrush1, IBX1, IBY1, IBW1, IBH1, 5)
, Gdip_DrawRoundedRectangle(G1, pPen2, IBX2, IBY2, IBW2, IBH2, 5)
, Gdip_TextToGraphics(G1, InfoText, FontOptions1, Font, A_ScreenWidth, A_ScreenHeight)
, Gdip_FillRoundedRectangle(G1, pBrush1, ABX1, ABY1, ABW1, ABH1, 5)
, Gdip_DrawRoundedRectangle(G1, pPen2, ABX2, ABY2, ABW2, ABH2, 5)
 
; Axis bars
Axis_Info := ""
for key, val in Axis_Array {
GetKeyState, joy_%val%, % JoystickNumber "Joy" val
Axis_Info .= val joy_%val% " "
if (joy_%val% > 50)
%val%Y := BarCenter
, %val%h1 := (joy_%val% - 50) * ScaleY1
else
%val%Y := AxisLabelHeight + joy_%val% * ScaleY1 ;
, Sc - (joy_%val% - 50) * ScaleY1
, %val%h1 := BarCenter - %val%Y
Gdip_FillRoundedRectangle(G1, pBrush2, %val%X, %val%Y, BarWidth, %val%h1, 2)
, Gdip_DrawRoundedRectangle(G1, pPen1, %val%X, AxisLabelHeight, BarWidth, BarHeight, 5)
, Gdip_DrawRoundedRectangle(G1, pPen2, %val%X, AxisLabelHeight, BarWidth, BarHeight, 5)
, Gdip_TextToGraphics(G1, val, "x" (%val%X + AxisTextOffset) FontOptions2, Font, A_ScreenWidth, A_ScreenHeight)
}
 
; POV hat
If (P) {
GetKeyState, Joy_P, %JoystickNumber%JoyPOV
Axis_Info .= " POV" Joy_P
if (Joy_P > -1) {
StartAngle := (Joy_P > 33750 || Joy_P <= 2250) ? 247.5 ; up
: Joy_P > 29250 ? 202.5 ; up left
: Joy_P > 24750 ? 157.5 ; left
: Joy_P > 20250 ? 112.5 ; down left
: Joy_P > 15750 ? 67.5 ; down
: Joy_P > 11250 ? 22.5 ; down right
: Joy_P > 6750 ? 337.5 ; right
: 292.5 ; up right
, Gdip_FillPie(G1, pBrush2, PieX, PieY, PieSize, PieSize, StartAngle, 45)
, Gdip_DrawPie(G1, pPen1, PieX, PieY, PieSize, PieSize, StartAngle, 45)
, Gdip_DrawPie(G1, pPen2, PieX, PieY, PieSize, PieSize, StartAngle, 45)
}
}
 
; Crosshair 1
CenterX := ScaleX * joy_x
, CenterY := ScaleY2 * joy_y
, Gdip_DrawLine(G1, pPen3, CenterX-CrosshairOffset, CenterY, CenterX+CrosshairOffset, CenterY)
, Gdip_DrawLine(G1, pPen3, CenterX, CenterY-CrosshairOffset, CenterX, CenterY+CrosshairOffset)
, Gdip_DrawEllipse(G1, pPen4, CenterX-CircleOffset, CenterY-CircleOffset, CircleSize, CircleSize)
, Gdip_DrawEllipse(G1, pPen4, CenterX-3, CenterY-3, 6, 6)
 
; Crosshair 2
if ((R || U) && Show2ndCrosshair)
CenterU := ScaleX * joy_u
, CenterR := ScaleY2 * joy_r
, Gdip_DrawLine(G1, pPen5, CenterU-CrosshairOffset, CenterR, CenterU+CrosshairOffset, CenterR)
, Gdip_DrawLine(G1, pPen5, CenterU, CenterR-CrosshairOffset, CenterU, CenterR+CrosshairOffset)
, Gdip_DrawEllipse(G1, pPen6, CenterU-CircleOffset, CenterR-CircleOffset, CircleSize, CircleSize)
, Gdip_DrawEllipse(G1, pPen6, CenterU-3, CenterR-3, 6, 6)
 
UpdateLayeredWindow(hwnd1, hdc, 0, 0, A_ScreenWidth, A_ScreenHeight)
, Gdip_GraphicsClear(G1)
}
return
 
^Esc::
Exit:
Gdip_Shutdown(pToken)
ExitApp

BBC BASIC[edit]

      VDU 23,22,512;512;8,16,16,0
VDU 5
 
GCOL 4,15
REPEAT
B% = ADVAL(0)
X% = ADVAL(1) / 64
Y% = 1023 - ADVAL(2) / 64
PROCjoy(B%,X%,Y%)
WAIT 4
PROCjoy(B%,X%,Y%)
UNTIL FALSE
END
 
DEF PROCjoy(B%,X%,Y%)
LOCAL I%
LINE X%-32,Y%,X%+32,Y% : LINE X%,Y%-32,X%,Y%+32
VDU 30
FOR I% = 0 TO 15
IF B% AND 1<<I% THEN PRINT "Button "; I%+1 " pressed";
VDU 10,13
NEXT
ENDPROC


C[edit]

#include <stdio.h>
#include <stdlib.h>
 
void clear() {
for(int n = 0;n < 10; n++) {
printf("\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\r\n\r\n\r\n");
}
}
 
#define UP "00^00\r\n00|00\r\n00000\r\n"
#define DOWN "00000\r\n00|00\r\n00v00\r\n"
#define LEFT "00000\r\n<--00\r\n00000\r\n"
#define RIGHT "00000\r\n00-->\r\n00000\r\n"
#define HOME "00000\r\n00+00\r\n00000\r\n"
 
int main() {
clear();
system("stty raw");
 
printf(HOME);
printf("space to exit; wasd to move\r\n");
char c = 1;
 
while(c) {
c = getc(stdin);
clear();
 
switch (c)
{
case 'a':
printf(LEFT);
break;
case 'd':
printf(RIGHT);
break;
case 'w':
printf(UP);
break;
case 's':
printf(DOWN);
break;
case ' ':
c = 0;
break;
default:
printf(HOME);
};
 
printf("space to exit; wasd key to move\r\n");
}
 
system("stty cooked");
system("clear");
return 1;
}
Output:

Commodore BASIC[edit]

Commodore VIC-20[edit]

The VIC-20 has only one control port. Even still, to be able to read all the possible inputs, we have to poll two different registers. VIA #1 handles most of the joystick inputs, VIA #2 handles the "right direction" input line. For proper operation, we must set the data direction on VIA#2 to input on bit 7 of the Port B register, and then return it to output when the program is completed in order to re-enable full function of the keyboard.

This program maps the values from both registers to bits 0 through 4 of a single byte so that logic is evaluated identical to the C-64 example below.

5 rem joystick - commodore vic-20 (expanded)
6 rem for rosetta code
10 print chr$(147);:poke 37154,peek(37154) and 127
15 j1=37137:j2=37152:sc=4118:co=37910:x=11:y=11
20 poke sc+x+y*22,43:poke co+x+y*22,0
25 j=(not peek(j1) and28)/4
30 j=j+(not peek(j1) and32)/2
35 j=j+(not peek(j2) and128)/16
40 print chr$(19);"joy: ";
45 get k$:if k$="q" then print chr$(147):poke 37154,peek(37154)or128:end
50 ox=x:oy=y
60 if(j and 1) then y=1:ud$="u"
61 if(j and 2) then y=21:ud$="d"
62 if(j and 3)=0 then y=11:ud$=" "
63 if(j and 4) then x=0:lr$="l"
64 if(j and 8) then x=21:lr$="r"
65 if(j and 12)=0 then x=11:lr$=" "
66 if(j and 16) then f$="fire!":c=24
67 if(j and 16)=0 then f$=" ":c=43
70 print tab(5);ud$;tab(7);lr$;tab(9);f$;
75 poke sc+x+y*22,c:poke co+x+y*22,0
80 if (ox=x) and (oy=y) then goto 100
85 poke sc+ox+oy*22,32
100 goto 25

Commodore 64[edit]

On the Commodore 64, both joystick ports can be read from registers on the CIA#1 6526 chip. This will report binary input from the joystick control ports in bits 0 through 4 (four directions plus a single fire or action button.) Control Port 1 is read from location 56321 and Control Port 2 is read from location 56320.

5 rem joystick - commodore 64
6 rem for rosetta code
8 rem black bkg, white text, dk. grey border
9 poke 53280,11:poke 53281,0:poke 646,1
10 print chr$(147);"joystick port 1 or 2";:input jp
11 if jp<1 or jp>2 then print:print"invalid.":print:goto 10
12 jp=(jp=2)+56321:print chr$(147);
15 sc=1024:x=20:y=12:poke sc+x+y*40,43
20 j=not peek(jp) and 31
25 print chr$(19);"{CRSR DOWN 24}joy status: ";
26 get k$:if k$="q" then print chr$(147):end
35 ox=x:oy=y
40 if(j and 1) then y=0:ud$="up "
45 if(j and 2) then y=23:ud$="down"
46 if(j and 3)=0 then y=12:ud$=" "
50 if(j and 4) then x=0:lr$="left "
55 if(j and 8) then x=39:lr$="right"
56 if(j and 12)=0 then x=20:lr$=" "
60 if(j and 16) then f$="fire!":c=24
61 if(j and 16)=0 then f$=" ":c=43
65 print tab(12);ud$;tab(17);lr$;tab(23);f$;
85 poke sc+x+y*40,c:if (ox=x) and (oy=y) then goto 100
90 poke sc+ox+oy*40,32
100 goto 20

Commodore Plus/4[edit]

The Commodore Plus/4 has the JOY(n) function available in BASIC v3.5 to read the position of a joystick plugged into control port n. The return value is a number 1 through 8 corresponding to each unique direction in a clockwise order, beginning with "up" returning a value of "1". Bit 7 of the return value will report the status of the fire button.

5 rem joystick - commodore plus/4
6 rem for rosetta code
8 rem black bkg, white text, dk. grey border
9 color 0,1:color 4,2,1:color 1,2,7
10 print chr$(147);"joystick port 1 or 2";:input jp
11 if jp<1 or jp>2 then print:print"invalid.":print:goto 10
12 print chr$(147);
15 sc=3072:x=20:y=13:poke sc+x+y*40,43
20 j=joy(jp)
25 print chr$(19);"joy status: ";
26 get k$:if k$="q" then print chr$(147):end
35 ox=x:oy=y
40 if(j and 15)=1 then d$="up ":x=20:y=1:goto 48
41 if(j and 15)=2 then d$="up right":x=39:y=1:goto 48
42 if(j and 15)=3 then d$=" right":x=39:y=13:goto 48
43 if(j and 15)=4 then d$="down right":x=39:y=24:goto 48
44 if(j and 15)=5 then d$="down ":x=20:y=24:goto 48
45 if(j and 15)=6 then d$="down left ":x=0:y=24:goto 48
46 if(j and 15)=7 then d$=" left ":x=0:y=13:goto 48
47 if(j and 15)=8 then d$="up left ":x=0:y=1
48 if(j and 128) then f$="fire!":c=24
49 if(j and 128)=0 then f$=" ":c=43
50 if(j=0) then d$=" ":x=20:y=13
65 print tab(12);d$;tab(23);f$;
85 poke sc+x+y*40,c:if (ox=x) and (oy=y) then goto 100
90 poke sc+ox+oy*40,32
100 goto 20

Commodore 128[edit]

BASIC 7.0 retains the same functionality of BASIC 3.5 on the Plus/4 for reading the joystick port(s). The C128 can take advantage of dual screen output.

5 rem joystick - commodore 128
6 rem for rosetta code
8 rem black bkg, white text, dk. grey border
9 color 0,1:color 4,12:color 1,2:graphic 0:scnclr 0:graphic 5
10 print chr$(147);"joystick port 1 or 2";:input jp
11 if jp<1 or jp>2 then print:print"invalid.":print:goto 10
12 print chr$(147);
15 sc=1024:x=20:y=12:poke sc+x+y*40,43
20 j=joy(jp)
25 print chr$(19);"joy status: ";
26 get k$:if k$="q" then print chr$(147):end
35 ox=x:oy=y
40 if(j and 15)=1 then d$="up ":x=20:y=0:goto 48
41 if(j and 15)=2 then d$="up right":x=39:y=0:goto 48
42 if(j and 15)=3 then d$=" right":x=39:y=12:goto 48
43 if(j and 15)=4 then d$="down right":x=39:y=24:goto 48
44 if(j and 15)=5 then d$="down ":x=20:y=24:goto 48
45 if(j and 15)=6 then d$="down left ":x=0:y=24:goto 48
46 if(j and 15)=7 then d$=" left ":x=0:y=12:goto 48
47 if(j and 15)=8 then d$="up left ":x=0:y=0
48 if(j and 128) then f$="fire!":c=24
49 if(j and 128)=0 then f$=" ":c=43
50 if(j=0) then d$=" ":x=20:y=12
65 print tab(12);d$;tab(23);f$;
85 poke sc+x+y*40,c:if (ox=x) and (oy=y)then goto 100
90 poke sc+ox+oy*40,32
100 goto 20

Delphi[edit]

Library: mmSystem

Form application version.

 
unit uMain;
 
interface
 
uses
Winapi.Windows, System.SysUtils, System.Classes, Vcl.Controls, Vcl.Forms,
Vcl.ExtCtrls, Vcl.StdCtrls;
 
type
TForm1 = class(TForm)
tmr1: TTimer;
lblPosition: TLabel;
procedure tmr1Timer(Sender: TObject);
procedure FormPaint(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
procedure DrawCrosshair(X, Y: Integer);
end;
 
var
Form1: TForm1;
X: Integer = 0;
Y: Integer = 0;
 
implementation
 
uses
mmSystem, Vcl.Graphics;
 
{$R *.dfm}
 
procedure TForm1.DrawCrosshair(X, Y: Integer);
const
RADIUS = 10;
CROSS = 3;
begin
Canvas.Brush.Color := clblack;
Canvas.FillRect(ClientRect);
with Canvas do
begin
Pen.Color := clWhite;
pen.Width := 1;
Ellipse(X - RADIUS, Y - RADIUS, X + RADIUS, Y + RADIUS);
pen.Width := 2;
MoveTo(X - CROSS * RADIUS, Y);
LineTo(X + CROSS * RADIUS, Y);
MoveTo(X, Y - CROSS * RADIUS);
LineTo(X, Y + CROSS * RADIUS);
end;
end;
 
procedure TForm1.FormPaint(Sender: TObject);
begin
DrawCrosshair(X, Y);
end;
 
procedure TForm1.tmr1Timer(Sender: TObject);
var
info: TJoyInfo;
begin
if (joyGetPos(0, @info) = 0) then
begin
X := Round(ClientWidth * info.wXpos / MAXWORD);
Y := Round(ClientHeight * info.wYpos / MAXWORD);
lblPosition.Caption := Format('(%3d,%3d)', [X, Y]);
Invalidate;
end;
end;
 
end.
 

Form resource:

 
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 600
ClientWidth = 600
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
OnPaint = FormPaint
PixelsPerInch = 96
TextHeight = 13
object lblPosition: TLabel
Left = 500
Top = 0
Width = 100
Height = 21
Alignment = taCenter
AutoSize = False
Caption = '(0,0)'
Font.Charset = DEFAULT_CHARSET
Font.Color = clWhite
Font.Height = -20
Font.Name = 'Tahoma'
Font.Style = []
ParentFont = False
end
object tmr1: TTimer
Interval = 500
OnTimer = tmr1Timer
end
end
 
Output:

Result preview [1]


Go[edit]

Library: termbox-go
Library: joystick(go)
package main
 
import (
"fmt"
"github.com/nsf/termbox-go"
"github.com/simulatedsimian/joystick"
"log"
"os"
"strconv"
"time"
)
 
func printAt(x, y int, s string) {
for _, r := range s {
termbox.SetCell(x, y, r, termbox.ColorDefault, termbox.ColorDefault)
x++
}
}
 
func readJoystick(js joystick.Joystick, hidden bool) {
jinfo, err := js.Read()
check(err)
 
w, h := termbox.Size()
tbcd := termbox.ColorDefault
termbox.Clear(tbcd, tbcd)
printAt(1, h-1, "q - quit")
if hidden {
printAt(11, h-1, "s - show buttons:")
} else {
bs := ""
printAt(11, h-1, "h - hide buttons:")
for button := 0; button < js.ButtonCount(); button++ {
if jinfo.Buttons&(1<<uint32(button)) != 0 {
// Buttons assumed to be numbered from 1, not 0.
bs += fmt.Sprintf(" %X", button+1)
}
}
printAt(28, h-1, bs)
}
 
// Map axis values in range -32767 to +32768 to termbox co-ordinates.
x := int(float64((jinfo.AxisData[0]+32767)*(w-1)) / 65535)
y := int(float64((jinfo.AxisData[1]+32767)*(h-2)) / 65535)
printAt(x, y, "+") // display crosshair
termbox.Flush()
}
 
func check(err error) {
if err != nil {
log.Fatal(err)
}
}
 
func main() {
// Under Linux the id is used to construct the joystick device name.
// For example: id 0 will open device: "/dev/input/js0"
// Under Windows the id is the actual numeric id of the joystick.
jsid := 0
// Optionally pass joystick id to be used as a command line argument.
if len(os.Args) > 1 {
i, err := strconv.Atoi(os.Args[1])
check(err)
jsid = i
}
 
js, jserr := joystick.Open(jsid)
check(jserr)
 
err := termbox.Init()
check(err)
defer termbox.Close()
 
eventQueue := make(chan termbox.Event)
go func() {
for {
eventQueue <- termbox.PollEvent()
}
}()
 
ticker := time.NewTicker(time.Millisecond * 40)
hidden := false // Controls whether button display hidden or not.
 
for doQuit := false; !doQuit; {
select {
case ev := <-eventQueue:
if ev.Type == termbox.EventKey {
if ev.Ch == 'q' {
doQuit = true
} else if ev.Ch == 'h' {
hidden = true
} else if ev.Ch == 's' {
hidden = false
}
}
if ev.Type == termbox.EventResize {
termbox.Flush()
}
case <-ticker.C:
readJoystick(js, hidden)
}
}
}

GUISS[edit]

Graphical User Interface Support Script only makes use of installed applications. So for this task, we use the joystick calibration routine, which shows a joystick position indicator:

Start,Control Panel, Game Controllers, List:installed controllers,Click:Joystick,
Button:Properties,Button:Test

Haskell[edit]

Half-solution of the problem, exhibits X and Y coordinates of the joystick; works on Windows (Haskell Platform):

import qualified Graphics.UI.GLFW as GLFW -- cabal install GLFW-b
import Graphics.Win32.Key
import Control.Monad.RWS.Strict (liftIO)
 
main = do
liftIO $ do
_ <- GLFW.init
GLFW.pollEvents
(jxrot, jyrot) <- liftIO $ getJoystickDirections GLFW.Joystick'1
putStrLn $ (show jxrot) ++ " " ++ (show jyrot)
w <- getAsyncKeyState 27 -- ESC pressed?
if (w<1) then main else do
GLFW.terminate
return ()
 
getJoystickDirections :: GLFW.Joystick -> IO (Double, Double)
 
getJoystickDirections js = do
maxes <- GLFW.getJoystickAxes js
return $ case maxes of
(Just (x:y:_)) -> (-y, x)
_ -> ( 0, 0)

IS-BASIC[edit]

100 CLEAR SCREEN
110 DO
120 LET J=JOY(0) OR JOY(1) OR JOY(2)
130 PRINT AT 1,1:" ";:PRINT AT 1,1:"";
140 IF J BAND 1 THEN PRINT "right ";
150 IF J BAND 2 THEN PRINT "left ";
160 IF J BAND 4 THEN PRINT "down ";
170 IF J BAND 8 THEN PRINT "up ";
180 IF J BAND 16 THEN PRINT "fire ";
190 LOOP

Julia[edit]

using CSFML.LibCSFML, Gtk.ShortNames, Colors, Graphics, Cairo
 
#------------ input code ----------------------#
 
mutable struct Joystick
devnum::Int
isconnected::Bool
hasXaxis::Bool
nbuttons::Int
pressed::Vector{Bool}
ypos::Int
xpos::Int
name::String
Joystick(n, b=2, c=false, x=true) = new(n, c, x, b, fill(false, b), 0, 0)
end
 
const devnum = 0
const buttons = 2
const jstick = Joystick(devnum, buttons)
 
function polljoystick(jstick, sleepinterval=0.05)
while !sfJoystick_isConnected(jstick.devnum)
sleep(0.25) # wait till connected
sfJoystick_update()
end
jstick.name = sfJoystick_getIdentification(jstick.devnum).name
jstick.isconnected = true
jstick.hasXaxis = sfJoystick_hasAxis(jstick.devnum, 0)
jstick.nbuttons = sfJoystick_getButtonCount(jstick.devnum)
while true
sfJoystick_update()
for i in 1:jstick.nbuttons
jstick.pressed[i] = sfJoystick_isButtonPressed(jstick.devnum, i - 1)
end
jstick.ypos = sfJoystick_getAxisPosition(jstick.devnum, 1)
jstick.xpos = sfJoystick_getAxisPosition(joystick.devnum, 0)
yield()
sleep(sleepinterval)
end
end
 
#------------ output code -------------------#
 
makelabel() = "Button 1: " * (jstick.pressed[1] ? "DOWN" : "UP") *
" Button 2: " * (jstick.pressed[2] ? "DOWN" : "UP")
 
const fontpointsize = 80
const wid = 500
const hei = 500
win = Window("Cursor Task", wid, hei) |> (Frame() |> (vbox = Box(:v)))
set_gtk_property!(vbox, :expand, true)
can = Canvas(wid, hei)
label = Label(makelabel())
push!(vbox, can, label)
 
joytoxpos() = div((jstick.xpos + 100) * width(can), 200)
joytoypos() = div((jstick.ypos + 100) * height(can), 200)
Gtk.showall(win)
 
@guarded draw(can) do widget
ctx = getgc(can)
select_font_face(ctx, "Courier", Cairo.FONT_SLANT_NORMAL, Cairo.FONT_WEIGHT_BOLD)
set_font_size(ctx, fontpointsize)
set_source(ctx, colorant"red")
move_to(ctx, joytoxpos(), joytoypos())
show_text(ctx, "+")
set_gtk_property!(label, :label, makelabel())
end
 
@async polljoystick(jstick)
 
while true
draw(can)
sleep(0.2)
yield()
end
 

Liberty BASIC[edit]

    'disable text window
nomainwin
 
'set window size
WindowWidth = 308
WindowHeight = 331
 
'center window on screen
UpperLeftX = int((DisplayWidth-WindowWidth)/2)
UpperLeftY = int((DisplayHeight-WindowHeight)/2)
 
'open graphics window
open "Joystick Position" for graphics_nf_nsb as #m
 
'trap window closing
#m "trapclose [quit]"
 
'put pen down
#m "down"
 
'get center of graphics window
#m "home"
#m "posxy CenterX CenterY"
 
'draw sprite for crosshair
#m "backcolor black; color black"
#m "place 0 20;boxfilled 20 40"
#m "line 0 10 20 10"
#m "line 10 0 10 20"
#m "place 10 10; circle 10"
#m "backcolor white; color red"
#m "line 0 30 20 30"
#m "line 10 20 10 40"
#m "place 10 30; circle 10"
#m "flush"
 
'get sprite image
#m "getbmp plus 0 0 20 40"
#m "cls"
 
'create sprite from image
#m "addsprite crosshair plus"
#m "centersprite crosshair"
#m "spritexy crosshair "; CenterX; " "; CenterY
#m "drawsprites"
 
'check joystick every 100 milliseconds
timer 100, [CheckJoystick]
wait
 
[CheckJoystick]
readjoystick 1
 
'calculate crosshair position
PosX = int(CenterX*Joy1x/32767)
PosY = int(CenterY*Joy1y/32767)
 
'update crosshair position
#m "spritexy crosshair "; PosX; " "; PosY
#m "drawsprites"
 
'display button information
if Joy1button1 > 0 then #m "place 0 0;\\Button 1 pressed"
if Joy1button2 > 0 then #m "place 0 0;\\\Button 2 pressed"
 
wait
 
[quit]
timer 0
close #m
unloadbmp "plus"
end

Locomotive Basic[edit]

10 MODE 1:BORDER 14:x=320:y=200:d=1
20 a=JOY(0) ' read state of first joystick
30 IF d THEN q$="*" ELSE q$=" "
40 IF a THEN MOVE x-8,y+8:TAG:PRINT q$;:TAGOFF
50 IF (a AND 1) AND y<380 THEN y=y+10
60 IF (a AND 2) AND y>20 THEN y=y-10
70 IF (a AND 4) AND x>20 THEN x=x-10
80 IF (a AND 8) AND x<620 THEN x=x+10
90 IF a AND 16 THEN LOCATE 1,1:PRINT "Fire1 pressed":d=1
100 IF a AND 32 THEN LOCATE 1,2:PRINT "Fire2 pressed":d=0
110 IF a<16 THEN LOCATE 1,1:PRINT " ":PRINT " "
120 MOVE x-8,y+8:TAG:PRINT "X";:TAGOFF
130 GOTO 20

Output (this version supports drawing with the cursor):

CPC drawing with joystick.png

Mathematica/Wolfram Language[edit]

Slider2D[Dynamic[ControllerState[{"X", "Y"}]], ImageSize -> {500, 500}]

OCaml[edit]

Library: SFML
Library: ocaml-sfml
let remove x = List.filter (fun y -> y <> x)
let buttons_string b =
String.concat " " (List.map string_of_int b)
 
let position app x y =
let view = SFRenderWindow.getView app in
let width, height = SFView.getSize view in
let hw = width /. 2.0 in
let hh = height /. 2.0 in
(hw +. ((x /. 100.0) *. hw),
hh +. ((y /. 100.0) *. hh))
 
let cross =
[| 1.0, 1.0; 10.0, 1.0; 10.0, -1.0; 1.0, -1.0;
1.0, -10.0; -1.0, -10.0; -1.0, -1.0; -10.0, -1.0;
-10.0, 1.0; -1.0, 1.0; -1.0, 10.0; 1.0, 10.0; |]
 
let () =
let app = SFRenderWindow.make (800, 600) "Joystick Position" in
let text = SFText.make "" in
let shape = SFShape.create cross in
SFShape.setFillColor shape SFColor.white;
SFShape.setOutlineColor shape SFColor.white;
SFShape.setOutlineThickness shape 1.0;
let rec display ((x, y), b) =
SFText.setString text (buttons_string b);
let x, y = position app x y in
SFShape.setPosition shape (x, y);
SFRenderWindow.clear app SFColor.black;
SFRenderWindow.drawText app text ();
SFRenderWindow.drawShape app shape ();
SFRenderWindow.display app;
and loop joyd =
let get_joystick (((x, y), b) as joyd) = function
| SFEvent.JoystickButtonPressed (0, button) -> ((x, y), button::b)
| SFEvent.JoystickButtonReleased (0, button) -> ((x, y), remove button b)
| SFEvent.JoystickMoved (0, SFJoystick.X, av) -> ((av, y), b)
| SFEvent.JoystickMoved (0, SFJoystick.Y, av) -> ((x, av), b)
| _ -> joyd
in
let rec proc_event joyd =
match SFRenderWindow.pollEvent app with
| Some SFEvent.KeyPressed (SFKey.Escape,_,_,_,_)
| Some SFEvent.Closed -> ()
| Some event ->
let joyd = get_joystick joyd event in
proc_event joyd
| None ->
display joyd;
loop joyd
in
proc_event joyd
in
loop ((0.0, 0.0), [])

Run with the command:

$ ocaml -I /tmp/ocaml-sfml/src sfml_system.cma sfml_window.cma sfml_graphics.cma joy.ml

Phix[edit]

Windows only, taken from http://phix.x10.mx/pmwiki/pmwiki.php?n=Main.JoystickPadLibrary

First, joy.e:

-- Joystick library for Euphoria (Windows)
-- /Mic, 2002
--
-- integer joy_init()
-- returns the number of joysticks attached to the computer
--
-- sequence joy_get_state(integer joy_num)
-- returns the current state of joystick #joy_num (can be either 1 or 2).
-- the format of the return sequence is:
-- {X_direction, Y_direction, Z_direction, buttons}
-- the X,Y and Z directions have 3 possible values; 0 (negative), 32768 (neutral) or 65535 (positive)
-- the buttons' status are represented by a single bit (button up, button down). e.g. to get the status
-- of button #3 on joystick #1 you'd use:
-- sequence state
-- state = joy_get_state(1)
-- if and_bits(state[4],4) then ... end if
--
include dll.e
include machine.e
 
constant joyinfo = allocate(32)
atom winmm
integer joyGetNumDevs,joyGetPos
 
winmm = open_dll("winmm.dll")
if (winmm <= 0) then
puts(1,"Unable to open winmm.dll")
abort(0)
end if
 
joyGetNumDevs = define_c_func(winmm,"joyGetNumDevs",{},C_UINT)
joyGetPos = define_c_func(winmm,"joyGetPos",{C_INT,C_POINTER},C_INT)
if (joyGetNumDevs<0) or (joyGetPos<0) then
puts(1,"Unable to link functions")
abort(0)
end if
 
global function joy_init()
integer joy1Attached,joy2Attached
integer numDevs = c_func(joyGetNumDevs,{})
if numDevs=0 then
return 0
end if
 
joy1Attached = (c_func(joyGetPos,{0,joyinfo}) != 167)
joy2Attached = (numDevs=2) and (c_func(joyGetPos,{1,joyinfo}) != 167)
 
return joy1Attached + (joy2Attached*2)
end function
 
global function joy_get_state(integer joy_num)
if joy_num=1 or joy_num=2 then
joy_num -= 1
if c_func(joyGetPos,{joy_num,joyinfo+(joy_num*16)}) then
-- ERROR
return {}
end if
return peek4u({joyinfo+(joy_num*16),4})
end if
return {}
end function

And a test program:

include joy.ew
 
if joy_init()=0 then
puts(1,"No joystick(s) attached!")
abort(0)
end if
 
sequence joy_info = {}, s
integer button_mask
 
puts(1,"Joystick test\nEntering input loop. Press a key to exit..\n\n")
 
while get_key()=-1 do
-- Get the state of joystick #1
s = joy_get_state(1)
 
-- Do not print info unless the state has changed
if not equal(s,joy_info) then
joy_info = s
 
printf(1,"X = %d, Y= %d ",{floor((s[1]-32767)/32768),floor((s[2]-32767)/32768)})
 
button_mask = 1
for i=1 to 8 do
if and_bits(s[4],button_mask) then
printf(1,"BTN%d ",i)
else
puts(1," ")
end if
button_mask *= 2
end for
puts(1,"\n")
end if
end while

PicoLisp[edit]

This is for the 64-bit version.

Library: GLUT

Note: The code is not yet tested with a real joystick (I don't have one), it was just simulated with dummy functions. Can somebody having a joystick please test it, and remove this message?

(load "@lib/openGl.l")
 
(setq *JoyX 0.0 *JoyY 0.0)
 
(glutInit)
(glutInitDisplayMode (| GLUT_RGBA GLUT_DOUBLE GLUT_ALPHA GLUT_DEPTH))
(glutInitWindowSize 400 400)
(glutCreateWindow "Joystick")
 
(glClearColor 0.3 0.3 0.5 0)
 
(displayPrg
(glClear GL_COLOR_BUFFER_BIT)
(glBegin GL_LINES)
(glVertex2f *JoyX (- *JoyY 0.1)) # Draw crosshair
(glVertex2f *JoyX (+ *JoyY 0.1))
(glVertex2f (- *JoyX 0.1) *JoyY)
(glVertex2f (+ *JoyX 0.1) *JoyY)
(glEnd)
(glFlush)
(glutSwapBuffers) )
 
# Track joystick position
(native `*GlutLib "glutJoystickFunc" NIL
(lisp 'joystickFunc
'((Btn X Y Z)
(msg # Display buttons
(make
(for (B 1 (n0 Btn) (inc B))
(and (bit? 1 Btn) (link B))
(setq Btn (>> 1 Btn)) ) ) )
(setq # Move crosshair
*JoyX (*/ X 1.0 1000)
*JoyY (*/ Y 1.0 1000) )
(glutPostRedisplay) ) )
100 )
 
# Exit upon mouse click
(mouseFunc '((Btn State X Y) (bye)))
(glutMainLoop)

PureBasic[edit]

This is limited to only digital joysticks.

If InitJoystick() = 0
MessageRequester("Error!", "Need to connect a joystick", #PB_MessageRequester_Ok)
End
EndIf
 
;some constants for Window positioning
#WindowW = 100: #WindowH = 100
#CrossW = 10
#p1 = (#WindowW - #CrossW) / 2
#p2 = (#WindowW / 2 - #CrossW)
 
If OpenWindow(0, 0, 0, #WindowW * 2 + 10, #WindowH, "Joystick Position", #PB_Window_SystemMenu)
CreateImage(0, #WindowW, #WindowW)
ImageGadget(0, 0, 0, 0, 0, ImageID(0))
TextGadget(2, #WindowW + 5, 10, #WindowW, 20, "Buttons Pressed:")
CreateImage(1, #WindowW, 40)
ImageGadget(1, #WindowW + 5, 30, 0, 0, ImageID(1))
 
AddKeyboardShortcut(0, #PB_Shortcut_Escape, 0)
Define event, x_movement, y_movement
Repeat
Repeat
event = WindowEvent()
Select event
Case #PB_Event_Menu
If EventMenu() = 0
End
EndIf
Case #PB_Event_CloseWindow
End
EndSelect
Until event = 0
 
Define pressed.s, buttonNum, buttonX, buttonY, buttonText.s, buttonColor
pressed.s = ""
If ExamineJoystick(0)
x_movement = JoystickAxisX(0)
y_movement = JoystickAxisY(0)
 
StartDrawing(ImageOutput(1))
DrawingMode(#PB_2DDrawing_Transparent)
Box(0, 0, #WindowW, 50, RGB($D4, $D0, $C8)) ;a Gray
; check to see if any of the buttons have been pressed
For buttonNum = 1 To 10
buttonX = ((buttonNum - 1) * 20 + 10) % #WindowW
buttonY = ((buttonNum - 1) / 5) * 20 + 10
If JoystickButton(0, buttonNum)
buttonColor = RGB($FF, 0, 0) ;Red
Else
buttonColor = RGB($80, $80, $80) ;Gray
EndIf
Circle(buttonX, buttonY, 9, buttonColor)
buttonText = Str(buttonNum)
DrawText(buttonX - TextWidth(buttonText) / 2, buttonY - TextHeight(buttonText) / 2, buttonText, RGB($FF, $FF, $FF)) ;White
Next
StopDrawing()
 
SetGadgetState(1, ImageID(1))
EndIf
 
 
StartDrawing(ImageOutput(0))
Box(0,0, #WindowW, #WindowW, RGB($FF, $FF, $FF)) ;White
Line(#p1 + x_movement * #p2, #WindowW / 2 + y_movement * #p2, #CrossW, 1, RGB($FF, 0, 0)) ;Red
Line(#WindowW / 2 + x_movement * #p2, #p1 + y_movement * #p2, 1, #CrossW, RGB($FF, 0, 0)) ;Red
StopDrawing()
 
SetGadgetState(0, ImageID(0))
 
Delay(10)
Until event = #PB_Event_CloseWindow
EndIf

JoystickPosition-PureBasic.png

Python[edit]

Library: Pygame
import sys
import pygame
 
pygame.init()
 
# Create a clock (for framerating)
clk = pygame.time.Clock()
 
# Grab joystick 0
if pygame.joystick.get_count() == 0:
raise IOError("No joystick detected")
joy = pygame.joystick.Joystick(0)
joy.init()
 
# Create display
size = width, height = 600, 600
screen = pygame.display.set_mode(size)
pygame.display.set_caption("Joystick Tester")
 
# Frame XHair zone
frameRect = pygame.Rect((45, 45), (510, 510))
 
# Generate crosshair
crosshair = pygame.surface.Surface((10, 10))
crosshair.fill(pygame.Color("magenta"))
pygame.draw.circle(crosshair, pygame.Color("blue"), (5,5), 5, 0)
crosshair.set_colorkey(pygame.Color("magenta"), pygame.RLEACCEL)
crosshair = crosshair.convert()
 
# Generate button surfaces
writer = pygame.font.Font(pygame.font.get_default_font(), 15)
buttons = {}
for b in range(joy.get_numbuttons()):
buttons[b] = [
writer.render(
hex(b)[2:].upper(),
1,
pygame.Color("red"),
pygame.Color("black")
).convert(),
# Get co-ords: ((width*slot)+offset, offset). Offsets chosen
# to match frames.
((15*b)+45, 560)
]
 
while True:
# Pump and check the events queue
pygame.event.pump()
for events in pygame.event.get():
if events.type == pygame.QUIT:
pygame.quit()
sys.exit()
 
# Black the screen
screen.fill(pygame.Color("black"))
 
# Get joystick axes
x = joy.get_axis(0)
y = joy.get_axis(1)
 
# Blit to the needed coords:
# x*amplitude+(centre offset (window size/2))-(xhair offset (xh size/2))
screen.blit(crosshair, ((x*250)+300-5, (y*250)+300-5))
pygame.draw.rect(screen, pygame.Color("red"), frameRect, 1)
 
# Get and display the joystick buttons
for b in range(joy.get_numbuttons()):
if joy.get_button(b):
screen.blit(buttons[b][0], buttons[b][1])
 
# Write the display
pygame.display.flip()
clk.tick(40) # Limit to <=40 FPS

Raku[edit]

(formerly Perl 6)

Works with: Rakudo version 2020.011

Linux only terminal based joystick testing utility. Reads events from the joystick asynchronously, allows a main processing loop if desired. This uses the main loop to check for and compensate for a resized terminal but not really anything else. Hit control-c to exit; needs one extra event from the the joystick to exit completely. Only shows the first 3 axes, no matter how many are available. Tested with an Logitech extreme joystick and an Xbox controller.

use experimental :pack;
 
# Joysticks generally show up in the /dev/input/ directory as js(n) where n is
# the number assigned by the OS. E.G. /dev/input/js1 . In my particular case:
 
my $device = '/dev/input/js0';
 
my $exit = 0;
 
my $event-stream = $device.IO.open(:bin);
my $js = $event-stream.Supply(:8size);
 
my %config; # joystick configuration: number of axes and buttons
my %event; # global "joystick event"
 
%config<button>.push: 0;
 
my $callback = sub { update };
 
sub get-js-event ( $ev, &callback ) {
exit if $exit;
# 32 bit timestamp milliseconds. Allows easy checking for "double-click" button presses
%event<timestamp> = $ev.subbuf(0, 4).reverse.unpack('N');
 
# 16 bit (signed int16) value of current control
%event<value> = (my $v = $ev.subbuf(4, 2).unpack('S')) > 32767 ?? -65536 + $v !! $v;
 
# Two 8 bit integers, current event: control type, and control ID
(%event<type>, %event<number>) = $ev.subbuf(6).unpack('CC');
 
# Process the event
if %event<type> +& 128 { # initialing
given %event<type> +& 3 { # enumeration of control inputs
when 1 { %config<button>.push: %event<number> }
when 2 { %config<axis>.push: %event<number> }
}
} else {
# Optional callback subroutine to run every time a js event is received
callback
}
}
 
# read events from the joystick driver asynchronously
start react whenever $js { $js.act: { get-js-event($_, $callback) } }
 
# allow a short delay while driver initializes
sleep .5;
 
# clean up on exit
signal(SIGINT).tap: {
print "\e[0m", "\n" xx 50, "\e[H\e[J\e[?25hWaiting for one more joystick event...\n";
$exit = 1;
exit(0);
}
 
use Terminal::ANSIColor;
 
my ($rows, $cols) = qx/stty size/.words; # get the terminal size
 
my $xhair = '╺╋╸';
my $axis = '█';
my @btext = %config<button>.map: { sprintf( "%2d", $_) };
my @button = @btext.map: {color('bold white on_blue ') ~ $_ ~ color('reset')};
my ($x, $y, $z) = ($rows/2).floor, ($cols/2).floor, 0;
 
sub update {
given %event<type> {
when 1 { # button event
given %event<value> {
when 0 { @button[%event<number>] = color('bold white on_blue ') ~ @btext[%event<number>] ~ color('reset') }
when 1 { @button[%event<number>] = color('bold white on_green') ~ @btext[%event<number>] ~ color('reset') }
}
}
when 2 { # axis events
given %event<number> {
when 0 { $y = ($cols / 2 + %event<value> / 32767 * $cols / 2).Int max 1 }
when 1 { $x = ($rows / 2 + %event<value> / 32767 * $rows / 2).Int max 2 }
when 2 { $z = (%event<value> / 32767 * 100).Int }
default { } # only using the first 3 axes, ignore ant others
}
$x min= $rows - 1;
$y min= $cols - 1;
}
}
print "\e[H\e[J\e[1;1H";
print " ", join " ", flat @button, "Axis 0: $x", "Axis 1: $y" , "Axis 2: $z%\n";
my $bar = ($z / 100 * $cols / 2).floor;
if $bar < 0 {
print ' ' x ($bar + $cols / 2).floor, color('bold green') ~ $axis x -$bar ~ color('reset');
} else {
print ' ' x $cols / 2, color('bold green') ~ $axis x $bar ~ color('reset');
}
print "\e[{$x};{$y}H", color('bold yellow') ~ $xhair ~ color('reset');
}
 
print "\e[?25l"; # hide the cursor
update; # initial update
 
# Main loop, operates independently of the joystick event loop
loop {
once say " Joystick has {%config<axis>.elems} axes and {%config<button>.elems} buttons";
sleep 1;
($rows, $cols) = qx/stty size/.words;
}
 

Tcl[edit]

Library: Tk
Library: mkLibsdl
package require Tk 8.6
package require mkLibsdl
 
# This code assumes we're dealing with the first pair of axes on the first
# joystick; modern joysticks are complex...
 
# Callback for all joystick activity
proc display {joyDict} {
global x y buttons message
set axis -1
dict with joyDict {
if {$joystick != 0} return
if {[info exist button]} {
# Handle button presses...
set buttons($button) $value
set message "Buttons:"
foreach b [lsort -integer [array names buttons]] {
if {$buttons($b)} {
lappend message $b
}
}
} else {
# Handle joystick movement...
if {$axis == -1} return
set value [expr {$value / 32768.0 * 100 + 120}]
if {$axis == 0} {
set x $value
} elseif {$axis == 1} {
set y $value
}
.c coords xhairV $x [expr {$y-5}] $x [expr {$y+5}]
.c coords xhairH [expr {$x-5}] $y [expr {$x+5}] $y
}
}
}
 
# Make a GUI
set message "Buttons:"
pack [canvas .c -width 240 -height 240] [label .l -textvariable message]
set x [set y 120]
.c create line {120 115 120 125} -tags xhairV
.c create line {115 120 125 120} -tags xhairH
joystick event eval {display [joystick event peek]}

ZX Spectrum Basic[edit]

Assuming a Kempston joystick interface, fairly standard at the time. Rewriting for the Sinclair Interface 2 involves changing line 80 to 80 LET t=IN 61438, replacing all numbers in the next five lines with 191-said number and reversing each pair of directions.

10 DIM o$(5)
20 LET xm=0: LET xx=31: REM screen limits
30 LET ym=0: LET yx=18
40 LET xo=16: LET yo=9: REM origin
50 LET xc=xo: LET yc=yo
60 PRINT AT yc,xc;" ": REM entry point for scan loop - blank cursor
70 LET xc=xo: LET yc=yo
80 LET t=IN 31
90 IF t=1 OR t=5 OR t=9 OR t=17 OR t=21 OR t=25 THEN LET xc=xx: LET o$(2)="R": REM right
100 IF t=2 OR t=6 OR t=10 OR t=18 OR t=22 OR t=26 THEN LET xc=xm: LET o$(1)="L": REM left
110 IF t=4 OR t=5 OR t=6 OR t=20 OR t=21 OR t=22 THEN LET yc=yx: LET o$(4)="D": REM down
120 IF t=8 OR t=9 OR t=10 OR t=24 OR t=25 OR t=26 THEN LET yc=ym: LET o$(3)="U": REM up
130 IF t>=16 THEN LET o$(5)="F": REM fire
140 PRINT AT 21,0;"Input:";o$
150 PRINT AT yc,xc;"+"
160 LET o$=" ": REM five spaces to blank output line again
170 GO TO 60
Output:
+

Input:L  D