SDL  2.0
Macros | Functions | Variables
testjoystick.c File Reference
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SDL.h"
+ Include dependency graph for testjoystick.c:

Go to the source code of this file.

Macros

#define SCREEN_WIDTH   640
#define SCREEN_HEIGHT   480

Functions

static void DrawRect (SDL_Renderer *r, const int x, const int y, const int w, const int h)
void loop (void *arg)
static SDL_bool WatchJoystick (SDL_Joystick *joystick)
int main (int argc, char *argv[])

Variables

SDL_Renderer * screen = NULL
SDL_bool retval = SDL_FALSE
SDL_bool done = SDL_FALSE

Macro Definition Documentation

#define SCREEN_HEIGHT   480

Definition at line 32 of file testjoystick.c.

Referenced by loop(), and WatchJoystick().

#define SCREEN_WIDTH   640

Definition at line 31 of file testjoystick.c.

Referenced by loop(), and WatchJoystick().

Function Documentation

static void DrawRect ( SDL_Renderer *  r,
const int  x,
const int  y,
const int  w,
const int  h 
)
static

Definition at line 40 of file testjoystick.c.

References SDL_RenderFillRect.

Referenced by loop().

{
const SDL_Rect area = { x, y, w, h };
SDL_RenderFillRect(r, &area);
}
void loop ( void *  arg)

Definition at line 47 of file testjoystick.c.

References SDL_JoyAxisEvent::axis, SDL_JoyBallEvent::ball, SDL_JoyButtonEvent::button, done, DrawRect(), SDL_JoyHatEvent::hat, i, SDL_Event::jaxis, SDL_Event::jball, SDL_Event::jbutton, SDL_Event::jdevice, SDL_Event::jhat, SDL_Event::key, SDL_KeyboardEvent::keysym, retval, SCREEN_HEIGHT, SCREEN_WIDTH, SDL_ALPHA_OPAQUE, SDL_FINGERDOWN, SDL_HAT_CENTERED, SDL_HAT_DOWN, SDL_HAT_LEFT, SDL_HAT_RIGHT, SDL_HAT_UP, SDL_JOYAXISMOTION, SDL_JOYBALLMOTION, SDL_JOYBUTTONDOWN, SDL_JOYBUTTONUP, SDL_JOYDEVICEREMOVED, SDL_JOYHATMOTION, SDL_JoystickGetAttached, SDL_JoystickGetAxis, SDL_JoystickGetButton, SDL_JoystickGetHat, SDL_JoystickInstanceID, SDL_JoystickNumAxes, SDL_JoystickNumButtons, SDL_JoystickNumHats, SDL_JoystickRumble, SDL_KEYDOWN, SDL_Log, SDL_MOUSEBUTTONDOWN, SDL_PollEvent, SDL_PRESSED, SDL_QUIT, SDL_RenderClear, SDL_RenderPresent, SDL_SetRenderDrawColor, SDL_TRUE, SDLK_AC_BACK, SDLK_ESCAPE, SDL_Keysym::sym, SDL_Event::type, SDL_JoyAxisEvent::value, SDL_JoyHatEvent::value, SDL_JoyAxisEvent::which, SDL_JoyBallEvent::which, SDL_JoyHatEvent::which, SDL_JoyButtonEvent::which, SDL_JoyDeviceEvent::which, SDL_JoyBallEvent::xrel, and SDL_JoyBallEvent::yrel.

{
SDL_Event event;
int i;
SDL_Joystick *joystick = (SDL_Joystick *)arg;
/* blank screen, set up for drawing this frame. */
SDL_SetRenderDrawColor(screen, 0x0, 0x0, 0x0, SDL_ALPHA_OPAQUE);
SDL_RenderClear(screen);
while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_JOYDEVICEREMOVED:
SDL_Log("Joystick device %d removed.\n", (int) event.jdevice.which);
SDL_Log("Our instance ID is %d\n", (int) SDL_JoystickInstanceID(joystick));
break;
case SDL_JOYAXISMOTION:
SDL_Log("Joystick %d axis %d value: %d\n",
event.jaxis.which,
event.jaxis.axis, event.jaxis.value);
break;
case SDL_JOYHATMOTION:
SDL_Log("Joystick %d hat %d value:",
event.jhat.which, event.jhat.hat);
if (event.jhat.value == SDL_HAT_CENTERED)
SDL_Log(" centered");
if (event.jhat.value & SDL_HAT_UP)
SDL_Log(" up");
if (event.jhat.value & SDL_HAT_RIGHT)
SDL_Log(" right");
if (event.jhat.value & SDL_HAT_DOWN)
SDL_Log(" down");
if (event.jhat.value & SDL_HAT_LEFT)
SDL_Log(" left");
SDL_Log("\n");
break;
case SDL_JOYBALLMOTION:
SDL_Log("Joystick %d ball %d delta: (%d,%d)\n",
event.jball.which,
event.jball.ball, event.jball.xrel, event.jball.yrel);
break;
case SDL_JOYBUTTONDOWN:
SDL_Log("Joystick %d button %d down\n",
event.jbutton.which, event.jbutton.button);
/* First button triggers a 0.5 second full strength rumble */
if (event.jbutton.button == 0) {
SDL_JoystickRumble(joystick, 0xFFFF, 0xFFFF, 500);
}
break;
case SDL_JOYBUTTONUP:
SDL_Log("Joystick %d button %d up\n",
event.jbutton.which, event.jbutton.button);
break;
case SDL_KEYDOWN:
if ((event.key.keysym.sym != SDLK_ESCAPE) &&
(event.key.keysym.sym != SDLK_AC_BACK)) {
break;
}
/* Fall through to signal quit */
case SDL_FINGERDOWN:
case SDL_MOUSEBUTTONDOWN:
case SDL_QUIT:
done = SDL_TRUE;
break;
default:
break;
}
}
/* Update visual joystick state */
SDL_SetRenderDrawColor(screen, 0x00, 0xFF, 0x00, SDL_ALPHA_OPAQUE);
for (i = 0; i < SDL_JoystickNumButtons(joystick); ++i) {
if (SDL_JoystickGetButton(joystick, i) == SDL_PRESSED) {
DrawRect(screen, (i%20) * 34, SCREEN_HEIGHT - 68 + (i/20) * 34, 32, 32);
}
}
SDL_SetRenderDrawColor(screen, 0xFF, 0x00, 0x00, SDL_ALPHA_OPAQUE);
for (i = 0; i < SDL_JoystickNumAxes(joystick); ++i) {
/* Draw the X/Y axis */
int x, y;
x = (((int) SDL_JoystickGetAxis(joystick, i)) + 32768);
x *= SCREEN_WIDTH;
x /= 65535;
if (x < 0) {
x = 0;
} else if (x > (SCREEN_WIDTH - 16)) {
x = SCREEN_WIDTH - 16;
}
++i;
if (i < SDL_JoystickNumAxes(joystick)) {
y = (((int) SDL_JoystickGetAxis(joystick, i)) + 32768);
} else {
y = 32768;
}
y *= SCREEN_HEIGHT;
y /= 65535;
if (y < 0) {
y = 0;
} else if (y > (SCREEN_HEIGHT - 16)) {
y = SCREEN_HEIGHT - 16;
}
DrawRect(screen, x, y, 16, 16);
}
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0xFF, SDL_ALPHA_OPAQUE);
for (i = 0; i < SDL_JoystickNumHats(joystick); ++i) {
/* Derive the new position */
int x = SCREEN_WIDTH/2;
int y = SCREEN_HEIGHT/2;
const Uint8 hat_pos = SDL_JoystickGetHat(joystick, i);
if (hat_pos & SDL_HAT_UP) {
y = 0;
} else if (hat_pos & SDL_HAT_DOWN) {
y = SCREEN_HEIGHT-8;
}
if (hat_pos & SDL_HAT_LEFT) {
x = 0;
} else if (hat_pos & SDL_HAT_RIGHT) {
x = SCREEN_WIDTH-8;
}
DrawRect(screen, x, y, 8, 8);
}
SDL_RenderPresent(screen);
if (SDL_JoystickGetAttached( joystick ) == 0) {
done = SDL_TRUE;
retval = SDL_TRUE; /* keep going, wait for reattach. */
}
#ifdef __EMSCRIPTEN__
if (done) {
emscripten_cancel_main_loop();
}
#endif
}
int main ( int  argc,
char *  argv[] 
)

Definition at line 244 of file testjoystick.c.

References device, i, main, NULL, SDL_assert, SDL_FALSE, SDL_FINGERDOWN, SDL_GetError, SDL_HINT_ACCELEROMETER_AS_JOYSTICK, SDL_Init, SDL_INIT_JOYSTICK, SDL_INIT_VIDEO, SDL_JOYDEVICEADDED, SDL_JOYSTICK_TYPE_ARCADE_PAD, SDL_JOYSTICK_TYPE_ARCADE_STICK, SDL_JOYSTICK_TYPE_DANCE_PAD, SDL_JOYSTICK_TYPE_DRUM_KIT, SDL_JOYSTICK_TYPE_FLIGHT_STICK, SDL_JOYSTICK_TYPE_GAMECONTROLLER, SDL_JOYSTICK_TYPE_GUITAR, SDL_JOYSTICK_TYPE_THROTTLE, SDL_JOYSTICK_TYPE_WHEEL, SDL_JoystickClose, SDL_JoystickFromInstanceID, SDL_JoystickGetGUID, SDL_JoystickGetGUIDString, SDL_JoystickGetProduct, SDL_JoystickGetType, SDL_JoystickGetVendor, SDL_JoystickInstanceID, SDL_JoystickNameForIndex, SDL_JoystickNumAxes, SDL_JoystickNumBalls, SDL_JoystickNumButtons, SDL_JoystickNumHats, SDL_JoystickOpen, SDL_Log, SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO, SDL_LogError, SDL_LogSetPriority, SDL_MOUSEBUTTONDOWN, SDL_NumJoysticks, SDL_QUIT, SDL_QuitSubSystem, SDL_SetHint, SDL_TRUE, SDL_WaitEvent, SDL_Event::type, and WatchJoystick().

{
const char *name, *type;
int i;
SDL_Joystick *joystick;
SDL_SetHint(SDL_HINT_ACCELEROMETER_AS_JOYSTICK, "0");
/* Enable standard application logging */
SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
/* Initialize SDL (Note: video is required to start event loop) */
if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
exit(1);
}
/* Print information about the joysticks */
SDL_Log("There are %d joysticks attached\n", SDL_NumJoysticks());
for (i = 0; i < SDL_NumJoysticks(); ++i) {
name = SDL_JoystickNameForIndex(i);
SDL_Log("Joystick %d: %s\n", i, name ? name : "Unknown Joystick");
joystick = SDL_JoystickOpen(i);
if (joystick == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_JoystickOpen(%d) failed: %s\n", i,
SDL_GetError());
} else {
char guid[64];
SDL_assert(SDL_JoystickFromInstanceID(SDL_JoystickInstanceID(joystick)) == joystick);
SDL_JoystickGetGUIDString(SDL_JoystickGetGUID(joystick),
guid, sizeof (guid));
switch (SDL_JoystickGetType(joystick)) {
case SDL_JOYSTICK_TYPE_GAMECONTROLLER:
type = "Game Controller";
break;
case SDL_JOYSTICK_TYPE_WHEEL:
type = "Wheel";
break;
case SDL_JOYSTICK_TYPE_ARCADE_STICK:
type = "Arcade Stick";
break;
case SDL_JOYSTICK_TYPE_FLIGHT_STICK:
type = "Flight Stick";
break;
case SDL_JOYSTICK_TYPE_DANCE_PAD:
type = "Dance Pad";
break;
case SDL_JOYSTICK_TYPE_GUITAR:
type = "Guitar";
break;
case SDL_JOYSTICK_TYPE_DRUM_KIT:
type = "Drum Kit";
break;
case SDL_JOYSTICK_TYPE_ARCADE_PAD:
type = "Arcade Pad";
break;
case SDL_JOYSTICK_TYPE_THROTTLE:
type = "Throttle";
break;
default:
type = "Unknown";
break;
}
SDL_Log(" type: %s\n", type);
SDL_Log(" axes: %d\n", SDL_JoystickNumAxes(joystick));
SDL_Log(" balls: %d\n", SDL_JoystickNumBalls(joystick));
SDL_Log(" hats: %d\n", SDL_JoystickNumHats(joystick));
SDL_Log(" buttons: %d\n", SDL_JoystickNumButtons(joystick));
SDL_Log("instance id: %d\n", SDL_JoystickInstanceID(joystick));
SDL_Log(" guid: %s\n", guid);
SDL_Log(" VID/PID: 0x%.4x/0x%.4x\n", SDL_JoystickGetVendor(joystick), SDL_JoystickGetProduct(joystick));
SDL_JoystickClose(joystick);
}
}
#if defined(__ANDROID__) || defined(__IPHONEOS__)
if (SDL_NumJoysticks() > 0) {
#else
if (argv[1]) {
#endif
SDL_bool reportederror = SDL_FALSE;
SDL_bool keepGoing = SDL_TRUE;
SDL_Event event;
int device;
#if defined(__ANDROID__) || defined(__IPHONEOS__)
device = 0;
#else
device = atoi(argv[1]);
#endif
joystick = SDL_JoystickOpen(device);
if (joystick != NULL) {
SDL_assert(SDL_JoystickFromInstanceID(SDL_JoystickInstanceID(joystick)) == joystick);
}
while ( keepGoing ) {
if (joystick == NULL) {
if ( !reportederror ) {
SDL_Log("Couldn't open joystick %d: %s\n", device, SDL_GetError());
keepGoing = SDL_FALSE;
reportederror = SDL_TRUE;
}
} else {
reportederror = SDL_FALSE;
keepGoing = WatchJoystick(joystick);
SDL_JoystickClose(joystick);
}
joystick = NULL;
if (keepGoing) {
SDL_Log("Waiting for attach\n");
}
while (keepGoing) {
SDL_WaitEvent(&event);
if ((event.type == SDL_QUIT) || (event.type == SDL_FINGERDOWN)
|| (event.type == SDL_MOUSEBUTTONDOWN)) {
keepGoing = SDL_FALSE;
} else if (event.type == SDL_JOYDEVICEADDED) {
device = event.jdevice.which;
joystick = SDL_JoystickOpen(device);
if (joystick != NULL) {
SDL_assert(SDL_JoystickFromInstanceID(SDL_JoystickInstanceID(joystick)) == joystick);
}
break;
}
}
}
}
SDL_QuitSubSystem(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);
return 0;
}
static SDL_bool WatchJoystick ( SDL_Joystick *  joystick)
static

Definition at line 191 of file testjoystick.c.

References done, loop(), NULL, retval, SCREEN_HEIGHT, SCREEN_WIDTH, SDL_ALPHA_OPAQUE, SDL_CreateRenderer, SDL_CreateWindow, SDL_DestroyRenderer, SDL_DestroyWindow, SDL_FALSE, SDL_GetError, SDL_JoystickInstanceID, SDL_JoystickName, SDL_JoystickNumAxes, SDL_JoystickNumBalls, SDL_JoystickNumButtons, SDL_JoystickNumHats, SDL_Log, SDL_LOG_CATEGORY_APPLICATION, SDL_LogError, SDL_RaiseWindow, SDL_RenderClear, SDL_RenderPresent, SDL_SetRenderDrawColor, and SDL_WINDOWPOS_CENTERED.

Referenced by main().

{
SDL_Window *window = NULL;
const char *name = NULL;
retval = SDL_FALSE;
done = SDL_FALSE;
/* Create a window to display joystick axis position */
window = SDL_CreateWindow("Joystick Test", SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH,
SCREEN_HEIGHT, 0);
if (window == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create window: %s\n", SDL_GetError());
return SDL_FALSE;
}
screen = SDL_CreateRenderer(window, -1, 0);
if (screen == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create renderer: %s\n", SDL_GetError());
SDL_DestroyWindow(window);
return SDL_FALSE;
}
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, SDL_ALPHA_OPAQUE);
SDL_RenderClear(screen);
SDL_RenderPresent(screen);
SDL_RaiseWindow(window);
/* Print info about the joystick we are watching */
name = SDL_JoystickName(joystick);
SDL_Log("Watching joystick %d: (%s)\n", SDL_JoystickInstanceID(joystick),
name ? name : "Unknown Joystick");
SDL_Log("Joystick has %d axes, %d hats, %d balls, and %d buttons\n",
SDL_JoystickNumAxes(joystick), SDL_JoystickNumHats(joystick),
SDL_JoystickNumBalls(joystick), SDL_JoystickNumButtons(joystick));
/* Loop, getting joystick events! */
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop_arg(loop, joystick, 0, 1);
#else
while (!done) {
loop(joystick);
}
#endif
SDL_DestroyRenderer(screen);
screen = NULL;
SDL_DestroyWindow(window);
return retval;
}

Variable Documentation

SDL_bool done = SDL_FALSE

Definition at line 37 of file testjoystick.c.

SDL_bool retval = SDL_FALSE

Definition at line 36 of file testjoystick.c.

SDL_Renderer* screen = NULL

Definition at line 35 of file testjoystick.c.