This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
testjoystick.c
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/*
Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely.
*/
/* Simple program to test the SDL joystick routines */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SDL.h"
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#ifndef SDL_JOYSTICK_DISABLED
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#ifdef __IPHONEOS__
#define SCREEN_WIDTH 320
#define SCREEN_HEIGHT 480
#else
#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480
#endif
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#define MAX_NUM_AXES 6
#define MAX_NUM_HATS 2
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static void
DrawRect(SDL_Renderer *r, const int x, const int y, const int w, const int h)
{
const SDL_Rect area = { x, y, w, h };
SDL_RenderFillRect(r, &area);
}
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WatchJoystick(SDL_Joystick * joystick)
{
SDL_Window *window = NULL;
SDL_Renderer *screen = NULL;
const char *name = NULL;
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SDL_bool retval = SDL_FALSE;
SDL_bool done = SDL_FALSE;
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SDL_Event event;
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/* Create a window to display joystick axis position */
window = SDL_CreateWindow("Joystick Test", SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH,
SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
if (window == NULL) {
fprintf(stderr, "Couldn't create window: %s\n", SDL_GetError());
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return SDL_FALSE;
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}
screen = SDL_CreateRenderer(window, -1, 0);
if (screen == NULL) {
fprintf(stderr, "Couldn't create renderer: %s\n", SDL_GetError());
SDL_DestroyWindow(window);
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return SDL_FALSE;
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}
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, SDL_ALPHA_OPAQUE);
SDL_RenderClear(screen);
SDL_RenderPresent(screen);
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SDL_RaiseWindow(window);
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/* Print info about the joystick we are watching */
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name = SDL_JoystickName(joystick);
printf("Watching joystick %d: (%s)\n", SDL_JoystickInstanceID(joystick),
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name ? name : "Unknown Joystick");
printf("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! */
while (!done) {
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/* blank screen, set up for drawing this frame. */
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, SDL_ALPHA_OPAQUE);
SDL_RenderClear(screen);
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while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_JOYAXISMOTION:
printf("Joystick %d axis %d value: %d\n",
event.jaxis.which,
event.jaxis.axis, event.jaxis.value);
break;
case SDL_JOYHATMOTION:
printf("Joystick %d hat %d value:",
event.jhat.which, event.jhat.hat);
if (event.jhat.value == SDL_HAT_CENTERED)
printf(" centered");
if (event.jhat.value & SDL_HAT_UP)
printf(" up");
if (event.jhat.value & SDL_HAT_RIGHT)
printf(" right");
if (event.jhat.value & SDL_HAT_DOWN)
printf(" down");
if (event.jhat.value & SDL_HAT_LEFT)
printf(" left");
printf("\n");
break;
case SDL_JOYBALLMOTION:
printf("Joystick %d ball %d delta: (%d,%d)\n",
event.jball.which,
event.jball.ball, event.jball.xrel, event.jball.yrel);
break;
case SDL_JOYBUTTONDOWN:
printf("Joystick %d button %d down\n",
event.jbutton.which, event.jbutton.button);
break;
case SDL_JOYBUTTONUP:
printf("Joystick %d button %d up\n",
event.jbutton.which, event.jbutton.button);
break;
case SDL_KEYDOWN:
if (event.key.keysym.sym != SDLK_ESCAPE) {
break;
}
/* Fall through to signal quit */
case SDL_QUIT:
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done = SDL_TRUE;
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break;
default:
break;
}
}
/* Update visual joystick state */
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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 * 34, SCREEN_HEIGHT - 34, 32, 32);
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SDL_SetRenderDrawColor(screen, 0xFF, 0x00, 0x00, SDL_ALPHA_OPAQUE);
for (i = 0; i < SDL_JoystickNumAxes(joystick) / 2; ++i) {
/* Draw the X/Y axis */
int x, y;
x = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 0)) + 32768);
x *= SCREEN_WIDTH;
x /= 65535;
if (x < 0) {
x = 0;
} else if (x > (SCREEN_WIDTH - 16)) {
x = SCREEN_WIDTH - 16;
}
y = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 1)) + 32768);
y *= SCREEN_HEIGHT;
y /= 65535;
if (y < 0) {
y = 0;
} else if (y > (SCREEN_HEIGHT - 16)) {
y = SCREEN_HEIGHT - 16;
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DrawRect(screen, x, y, 16, 16);
}
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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;
}
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if (hat_pos & SDL_HAT_LEFT) {
x = 0;
} else if (hat_pos & SDL_HAT_RIGHT) {
x = SCREEN_WIDTH-8;
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DrawRect(screen, x, y, 8, 8);
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SDL_RenderPresent(screen);
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if (SDL_JoystickGetAttached( joystick ) == 0) {
done = SDL_TRUE;
retval = SDL_TRUE; /* keep going, wait for reattach. */
}
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SDL_DestroyRenderer(screen);
SDL_DestroyWindow(window);
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return retval;
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}
int
main(int argc, char *argv[])
{
const char *name;
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SDL_Joystick *joystick;
/* Initialize SDL (Note: video is required to start event loop) */
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if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
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fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
exit(1);
}
/* Print information about the joysticks */
printf("There are %d joysticks attached\n", SDL_NumJoysticks());
for (i = 0; i < SDL_NumJoysticks(); ++i) {
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name = SDL_JoystickNameForIndex(i);
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printf("Joystick %d: %s\n", i, name ? name : "Unknown Joystick");
joystick = SDL_JoystickOpen(i);
if (joystick == NULL) {
fprintf(stderr, "SDL_JoystickOpen(%d) failed: %s\n", i,
SDL_GetError());
} else {
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char guid[64];
SDL_JoystickGetGUIDString(SDL_JoystickGetGUID(joystick),
guid, sizeof (guid));
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printf(" axes: %d\n", SDL_JoystickNumAxes(joystick));
printf(" balls: %d\n", SDL_JoystickNumBalls(joystick));
printf(" hats: %d\n", SDL_JoystickNumHats(joystick));
printf(" buttons: %d\n", SDL_JoystickNumButtons(joystick));
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printf("instance id: %d\n", SDL_JoystickInstanceID(joystick));
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printf(" guid: %s\n", guid);
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SDL_JoystickClose(joystick);
}
}
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if (argv[1]) {
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SDL_bool reportederror = SDL_FALSE;
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SDL_bool keepGoing = SDL_TRUE;
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SDL_Event event;
joystick = SDL_JoystickOpen(atoi(argv[1]));
while ( keepGoing ) {
if (joystick == NULL) {
if ( !reportederror ) {
printf("Couldn't open joystick %d: %s\n", atoi(argv[1]), SDL_GetError());
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keepGoing = SDL_FALSE;
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reportederror = SDL_TRUE;
}
} else {
reportederror = SDL_FALSE;
keepGoing = WatchJoystick(joystick);
SDL_JoystickClose(joystick);
}
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joystick = NULL;
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if (keepGoing) {
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printf("Waiting for attach\n");
}
while (keepGoing) {
SDL_WaitEvent(&event);
if (event.type == SDL_QUIT) {
keepGoing = SDL_FALSE;
} else if (event.type == SDL_JOYDEVICEADDED) {
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joystick = SDL_JoystickOpen(atoi(argv[1]));
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SDL_QuitSubSystem(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);
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#else
int
main(int argc, char *argv[])
{
fprintf(stderr, "SDL compiled without Joystick support.\n");
exit(1);
}
#endif