1 /*
2 Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
3
4 This software is provided 'as-is', without any express or implied
5 warranty. In no event will the authors be held liable for any damages
6 arising from the use of this software.
7
8 Permission is granted to anyone to use this software for any purpose,
9 including commercial applications, and to alter it and redistribute it
10 freely.
11 */
12
13 /* Simple program to test the SDL joystick routines */
14
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <string.h>
18
19 #include "SDL.h"
20
21 #ifdef __EMSCRIPTEN__
22 #include <emscripten/emscripten.h>
23 #endif
24
25 #ifndef SDL_JOYSTICK_DISABLED
26
27 #ifdef __IPHONEOS__
28 #define SCREEN_WIDTH 320
29 #define SCREEN_HEIGHT 480
30 #else
31 #define SCREEN_WIDTH 640
32 #define SCREEN_HEIGHT 480
33 #endif
34
35 static SDL_Window *window = NULL;
36 static SDL_Renderer *screen = NULL;
37 static SDL_Joystick *joystick = NULL;
38 static SDL_bool done = SDL_FALSE;
39
40 static void
PrintJoystick(SDL_Joystick * joystick)41 PrintJoystick(SDL_Joystick *joystick)
42 {
43 const char *type;
44 char guid[64];
45
46 SDL_assert(SDL_JoystickFromInstanceID(SDL_JoystickInstanceID(joystick)) == joystick);
47 SDL_JoystickGetGUIDString(SDL_JoystickGetGUID(joystick), guid, sizeof (guid));
48 switch (SDL_JoystickGetType(joystick)) {
49 case SDL_JOYSTICK_TYPE_GAMECONTROLLER:
50 type = "Game Controller";
51 break;
52 case SDL_JOYSTICK_TYPE_WHEEL:
53 type = "Wheel";
54 break;
55 case SDL_JOYSTICK_TYPE_ARCADE_STICK:
56 type = "Arcade Stick";
57 break;
58 case SDL_JOYSTICK_TYPE_FLIGHT_STICK:
59 type = "Flight Stick";
60 break;
61 case SDL_JOYSTICK_TYPE_DANCE_PAD:
62 type = "Dance Pad";
63 break;
64 case SDL_JOYSTICK_TYPE_GUITAR:
65 type = "Guitar";
66 break;
67 case SDL_JOYSTICK_TYPE_DRUM_KIT:
68 type = "Drum Kit";
69 break;
70 case SDL_JOYSTICK_TYPE_ARCADE_PAD:
71 type = "Arcade Pad";
72 break;
73 case SDL_JOYSTICK_TYPE_THROTTLE:
74 type = "Throttle";
75 break;
76 default:
77 type = "Unknown";
78 break;
79 }
80 SDL_Log("Joystick\n");
81 SDL_Log(" name: %s\n", SDL_JoystickName(joystick));
82 SDL_Log(" type: %s\n", type);
83 SDL_Log(" axes: %d\n", SDL_JoystickNumAxes(joystick));
84 SDL_Log(" balls: %d\n", SDL_JoystickNumBalls(joystick));
85 SDL_Log(" hats: %d\n", SDL_JoystickNumHats(joystick));
86 SDL_Log(" buttons: %d\n", SDL_JoystickNumButtons(joystick));
87 SDL_Log("instance id: %d\n", SDL_JoystickInstanceID(joystick));
88 SDL_Log(" guid: %s\n", guid);
89 SDL_Log(" VID/PID: 0x%.4x/0x%.4x\n", SDL_JoystickGetVendor(joystick), SDL_JoystickGetProduct(joystick));
90 }
91
92 static void
DrawRect(SDL_Renderer * r,const int x,const int y,const int w,const int h)93 DrawRect(SDL_Renderer *r, const int x, const int y, const int w, const int h)
94 {
95 const SDL_Rect area = { x, y, w, h };
96 SDL_RenderFillRect(r, &area);
97 }
98
99 void
loop(void * arg)100 loop(void *arg)
101 {
102 SDL_Event event;
103 int i;
104
105 /* blank screen, set up for drawing this frame. */
106 SDL_SetRenderDrawColor(screen, 0x0, 0x0, 0x0, SDL_ALPHA_OPAQUE);
107 SDL_RenderClear(screen);
108
109 while (SDL_PollEvent(&event)) {
110 switch (event.type) {
111
112 case SDL_JOYDEVICEADDED:
113 SDL_Log("Joystick device %d added.\n", (int) event.jdevice.which);
114 if (!joystick) {
115 joystick = SDL_JoystickOpen(event.jdevice.which);
116 if (joystick) {
117 PrintJoystick(joystick);
118 } else {
119 SDL_Log("Couldn't open joystick: %s\n", SDL_GetError());
120 }
121 }
122 break;
123
124 case SDL_JOYDEVICEREMOVED:
125 SDL_Log("Joystick device %d removed.\n", (int) event.jdevice.which);
126 if (event.jdevice.which == SDL_JoystickInstanceID(joystick)) {
127 SDL_JoystickClose(joystick);
128 joystick = SDL_JoystickOpen(0);
129 }
130 break;
131
132 case SDL_JOYAXISMOTION:
133 SDL_Log("Joystick %d axis %d value: %d\n",
134 event.jaxis.which,
135 event.jaxis.axis, event.jaxis.value);
136 break;
137 case SDL_JOYHATMOTION:
138 SDL_Log("Joystick %d hat %d value:",
139 event.jhat.which, event.jhat.hat);
140 if (event.jhat.value == SDL_HAT_CENTERED)
141 SDL_Log(" centered");
142 if (event.jhat.value & SDL_HAT_UP)
143 SDL_Log(" up");
144 if (event.jhat.value & SDL_HAT_RIGHT)
145 SDL_Log(" right");
146 if (event.jhat.value & SDL_HAT_DOWN)
147 SDL_Log(" down");
148 if (event.jhat.value & SDL_HAT_LEFT)
149 SDL_Log(" left");
150 SDL_Log("\n");
151 break;
152 case SDL_JOYBALLMOTION:
153 SDL_Log("Joystick %d ball %d delta: (%d,%d)\n",
154 event.jball.which,
155 event.jball.ball, event.jball.xrel, event.jball.yrel);
156 break;
157 case SDL_JOYBUTTONDOWN:
158 SDL_Log("Joystick %d button %d down\n",
159 event.jbutton.which, event.jbutton.button);
160 /* First button triggers a 0.5 second full strength rumble */
161 if (event.jbutton.button == 0) {
162 SDL_JoystickRumble(joystick, 0xFFFF, 0xFFFF, 500);
163 }
164 break;
165 case SDL_JOYBUTTONUP:
166 SDL_Log("Joystick %d button %d up\n",
167 event.jbutton.which, event.jbutton.button);
168 break;
169 case SDL_KEYDOWN:
170 /* Press the L key to lag for 3 seconds, to see what happens
171 when SDL doesn't service the event loop quickly. */
172 if (event.key.keysym.sym == SDLK_l) {
173 SDL_Log("Lagging for 3 seconds...\n");
174 SDL_Delay(3000);
175 break;
176 }
177
178 if ((event.key.keysym.sym != SDLK_ESCAPE) &&
179 (event.key.keysym.sym != SDLK_AC_BACK)) {
180 break;
181 }
182 /* Fall through to signal quit */
183 case SDL_FINGERDOWN:
184 case SDL_MOUSEBUTTONDOWN:
185 case SDL_QUIT:
186 done = SDL_TRUE;
187 break;
188 default:
189 break;
190 }
191 }
192
193 if (joystick) {
194
195 /* Update visual joystick state */
196 SDL_SetRenderDrawColor(screen, 0x00, 0xFF, 0x00, SDL_ALPHA_OPAQUE);
197 for (i = 0; i < SDL_JoystickNumButtons(joystick); ++i) {
198 if (SDL_JoystickGetButton(joystick, i) == SDL_PRESSED) {
199 DrawRect(screen, (i%20) * 34, SCREEN_HEIGHT - 68 + (i/20) * 34, 32, 32);
200 }
201 }
202
203 SDL_SetRenderDrawColor(screen, 0xFF, 0x00, 0x00, SDL_ALPHA_OPAQUE);
204 for (i = 0; i < SDL_JoystickNumAxes(joystick); ++i) {
205 /* Draw the X/Y axis */
206 int x, y;
207 x = (((int) SDL_JoystickGetAxis(joystick, i)) + 32768);
208 x *= SCREEN_WIDTH;
209 x /= 65535;
210 if (x < 0) {
211 x = 0;
212 } else if (x > (SCREEN_WIDTH - 16)) {
213 x = SCREEN_WIDTH - 16;
214 }
215 ++i;
216 if (i < SDL_JoystickNumAxes(joystick)) {
217 y = (((int) SDL_JoystickGetAxis(joystick, i)) + 32768);
218 } else {
219 y = 32768;
220 }
221 y *= SCREEN_HEIGHT;
222 y /= 65535;
223 if (y < 0) {
224 y = 0;
225 } else if (y > (SCREEN_HEIGHT - 16)) {
226 y = SCREEN_HEIGHT - 16;
227 }
228
229 DrawRect(screen, x, y, 16, 16);
230 }
231
232 SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0xFF, SDL_ALPHA_OPAQUE);
233 for (i = 0; i < SDL_JoystickNumHats(joystick); ++i) {
234 /* Derive the new position */
235 int x = SCREEN_WIDTH/2;
236 int y = SCREEN_HEIGHT/2;
237 const Uint8 hat_pos = SDL_JoystickGetHat(joystick, i);
238
239 if (hat_pos & SDL_HAT_UP) {
240 y = 0;
241 } else if (hat_pos & SDL_HAT_DOWN) {
242 y = SCREEN_HEIGHT-8;
243 }
244
245 if (hat_pos & SDL_HAT_LEFT) {
246 x = 0;
247 } else if (hat_pos & SDL_HAT_RIGHT) {
248 x = SCREEN_WIDTH-8;
249 }
250
251 DrawRect(screen, x, y, 8, 8);
252 }
253 }
254
255 SDL_RenderPresent(screen);
256
257 #ifdef __EMSCRIPTEN__
258 if (done) {
259 emscripten_cancel_main_loop();
260 }
261 #endif
262 }
263
264 int
main(int argc,char * argv[])265 main(int argc, char *argv[])
266 {
267 SDL_SetHint(SDL_HINT_ACCELEROMETER_AS_JOYSTICK, "0");
268
269 /* Enable standard application logging */
270 SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
271
272 /* Initialize SDL (Note: video is required to start event loop) */
273 if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
274 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
275 exit(1);
276 }
277
278 /* Create a window to display joystick axis position */
279 window = SDL_CreateWindow("Joystick Test", SDL_WINDOWPOS_CENTERED,
280 SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH,
281 SCREEN_HEIGHT, 0);
282 if (window == NULL) {
283 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create window: %s\n", SDL_GetError());
284 return SDL_FALSE;
285 }
286
287 screen = SDL_CreateRenderer(window, -1, 0);
288 if (screen == NULL) {
289 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create renderer: %s\n", SDL_GetError());
290 SDL_DestroyWindow(window);
291 return SDL_FALSE;
292 }
293
294 SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, SDL_ALPHA_OPAQUE);
295 SDL_RenderClear(screen);
296 SDL_RenderPresent(screen);
297
298 /* Loop, getting joystick events! */
299 #ifdef __EMSCRIPTEN__
300 emscripten_set_main_loop_arg(loop, NULL, 0, 1);
301 #else
302 while (!done) {
303 loop(NULL);
304 }
305 #endif
306
307 SDL_DestroyRenderer(screen);
308 SDL_DestroyWindow(window);
309
310 SDL_QuitSubSystem(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);
311
312 return 0;
313 }
314
315 #else
316
317 int
main(int argc,char * argv[])318 main(int argc, char *argv[])
319 {
320 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL compiled without Joystick support.\n");
321 return 1;
322 }
323
324 #endif
325
326 /* vi: set ts=4 sw=4 expandtab: */
327