This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
testjoystick.c
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/* Simple program to test the SDL joystick routines */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SDL.h"
#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480
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WatchJoystick(SDL_Joystick * joystick)
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SDL_Surface *screen;
const char *name;
int i, done;
SDL_Event event;
int x, y, draw;
SDL_Rect axis_area[6][2];
/* Set a video mode to display joystick axis position */
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screen = SDL_SetVideoMode(SCREEN_WIDTH, SCREEN_HEIGHT, 16, 0);
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if (screen == NULL) {
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fprintf(stderr, "Couldn't set video mode: %s\n", SDL_GetError());
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return;
}
/* Print info about the joystick we are watching */
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name = SDL_JoystickName(SDL_JoystickIndex(joystick));
printf("Watching joystick %d: (%s)\n", SDL_JoystickIndex(joystick),
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));
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/* Initialize drawing rectangles */
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memset(axis_area, 0, (sizeof axis_area));
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draw = 0;
/* Loop, getting joystick events! */
done = 0;
while (!done) {
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while (SDL_PollEvent(&event)) {
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switch (event.type) {
case SDL_JOYAXISMOTION:
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printf("Joystick %d axis %d value: %d\n",
event.jaxis.which,
event.jaxis.axis, event.jaxis.value);
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break;
case SDL_JOYHATMOTION:
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printf("Joystick %d hat %d value:",
event.jhat.which, event.jhat.hat);
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if (event.jhat.value == SDL_HAT_CENTERED)
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printf(" centered");
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if (event.jhat.value & SDL_HAT_UP)
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printf(" up");
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if (event.jhat.value & SDL_HAT_RIGHT)
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printf(" right");
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if (event.jhat.value & SDL_HAT_DOWN)
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printf(" down");
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if (event.jhat.value & SDL_HAT_LEFT)
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printf(" left");
printf("\n");
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break;
case SDL_JOYBALLMOTION:
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printf("Joystick %d ball %d delta: (%d,%d)\n",
event.jball.which,
event.jball.ball, event.jball.xrel, event.jball.yrel);
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break;
case SDL_JOYBUTTONDOWN:
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printf("Joystick %d button %d down\n",
event.jbutton.which, event.jbutton.button);
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break;
case SDL_JOYBUTTONUP:
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printf("Joystick %d button %d up\n",
event.jbutton.which, event.jbutton.button);
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break;
case SDL_KEYDOWN:
if (event.key.keysym.sym != SDLK_ESCAPE) {
break;
}
/* Fall through to signal quit */
case SDL_QUIT:
done = 1;
break;
default:
break;
}
}
/* Update visual joystick state */
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for (i = 0; i < SDL_JoystickNumButtons(joystick); ++i) {
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SDL_Rect area;
area.x = i * 34;
area.y = SCREEN_HEIGHT - 34;
area.w = 32;
area.h = 32;
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if (SDL_JoystickGetButton(joystick, i) == SDL_PRESSED) {
SDL_FillRect(screen, &area, 0xFFFF);
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SDL_FillRect(screen, &area, 0x0000);
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SDL_UpdateRects(screen, 1, &area);
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}
for (i = 0;
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i < SDL_JoystickNumAxes(joystick) / 2
&& i < SDL_arraysize(axis_area); ++i) {
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/* Erase previous axes */
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SDL_FillRect(screen, &axis_area[i][draw], 0x0000);
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/* Draw the X/Y axis */
draw = !draw;
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x = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 0)) + 32768);
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x *= SCREEN_WIDTH;
x /= 65535;
if (x < 0) {
x = 0;
} else if (x > (SCREEN_WIDTH - 16)) {
x = SCREEN_WIDTH - 16;
}
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y = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 1)) + 32768);
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y *= SCREEN_HEIGHT;
y /= 65535;
if (y < 0) {
y = 0;
} else if (y > (SCREEN_HEIGHT - 16)) {
y = SCREEN_HEIGHT - 16;
}
axis_area[i][draw].x = (Sint16) x;
axis_area[i][draw].y = (Sint16) y;
axis_area[i][draw].w = 16;
axis_area[i][draw].h = 16;
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SDL_FillRect(screen, &axis_area[i][draw], 0xFFFF);
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SDL_UpdateRects(screen, 2, axis_area[i]);
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}
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main(int argc, char *argv[])
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{
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const char *name;
int i;
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) {
fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
exit(1);
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}
/* Print information about the joysticks */
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printf("There are %d joysticks attached\n", SDL_NumJoysticks());
for (i = 0; i < SDL_NumJoysticks(); ++i) {
name = SDL_JoystickName(i);
printf("Joystick %d: %s\n", i, name ? name : "Unknown Joystick");
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}
if (argv[1]) {
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joystick = SDL_JoystickOpen(atoi(argv[1]));
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if (joystick == NULL) {
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printf("Couldn't open joystick %d: %s\n", atoi(argv[1]),
SDL_GetError());
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WatchJoystick(joystick);
SDL_JoystickClose(joystick);
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SDL_QuitSubSystem(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);
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return (0);
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}