1
2 /* Simple program to test the SDL joystick routines */
3
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <string.h>
7
8 #include "SDL.h"
9
10 #define SCREEN_WIDTH 640
11 #define SCREEN_HEIGHT 480
12
WatchJoystick(SDL_Joystick * joystick)13 void WatchJoystick(SDL_Joystick *joystick)
14 {
15 SDL_Surface *screen;
16 const char *name;
17 int i, done;
18 SDL_Event event;
19 int x, y, draw;
20 SDL_Rect axis_area[2];
21
22 /* Set a video mode to display joystick axis position */
23 screen = SDL_SetVideoMode(SCREEN_WIDTH, SCREEN_HEIGHT, 16, 0);
24 if ( screen == NULL ) {
25 fprintf(stderr, "Couldn't set video mode: %s\n",SDL_GetError());
26 return;
27 }
28
29 /* Print info about the joystick we are watching */
30 name = SDL_JoystickName(SDL_JoystickIndex(joystick));
31 printf("Watching joystick %d: (%s)\n", SDL_JoystickIndex(joystick),
32 name ? name : "Unknown Joystick");
33 printf("Joystick has %d axes, %d hats, %d balls, and %d buttons\n",
34 SDL_JoystickNumAxes(joystick), SDL_JoystickNumHats(joystick),
35 SDL_JoystickNumBalls(joystick),SDL_JoystickNumButtons(joystick));
36
37 /* Initialize drawing rectangles */
38 memset(axis_area, 0, (sizeof axis_area));
39 draw = 0;
40
41 /* Loop, getting joystick events! */
42 done = 0;
43 while ( ! done ) {
44 while ( SDL_PollEvent(&event) ) {
45 switch (event.type) {
46 case SDL_JOYAXISMOTION:
47 printf("Joystick %d axis %d value: %d\n",
48 event.jaxis.which,
49 event.jaxis.axis,
50 event.jaxis.value);
51 break;
52 case SDL_JOYHATMOTION:
53 printf("Joystick %d hat %d value:",
54 event.jhat.which,
55 event.jhat.hat);
56 if ( event.jhat.value == SDL_HAT_CENTERED )
57 printf(" centered");
58 if ( event.jhat.value & SDL_HAT_UP )
59 printf(" up");
60 if ( event.jhat.value & SDL_HAT_RIGHT )
61 printf(" right");
62 if ( event.jhat.value & SDL_HAT_DOWN )
63 printf(" down");
64 if ( event.jhat.value & SDL_HAT_LEFT )
65 printf(" left");
66 printf("\n");
67 break;
68 case SDL_JOYBALLMOTION:
69 printf("Joystick %d ball %d delta: (%d,%d)\n",
70 event.jball.which,
71 event.jball.ball,
72 event.jball.xrel,
73 event.jball.yrel);
74 break;
75 case SDL_JOYBUTTONDOWN:
76 printf("Joystick %d button %d down\n",
77 event.jbutton.which,
78 event.jbutton.button);
79 break;
80 case SDL_JOYBUTTONUP:
81 printf("Joystick %d button %d up\n",
82 event.jbutton.which,
83 event.jbutton.button);
84 break;
85 case SDL_KEYDOWN:
86 if ( event.key.keysym.sym != SDLK_ESCAPE ) {
87 break;
88 }
89 /* Fall through to signal quit */
90 case SDL_QUIT:
91 done = 1;
92 break;
93 default:
94 break;
95 }
96 }
97 /* Update visual joystick state */
98 for ( i=0; i<SDL_JoystickNumButtons(joystick); ++i ) {
99 SDL_Rect area;
100
101 area.x = i*34;
102 area.y = SCREEN_HEIGHT-34;
103 area.w = 32;
104 area.h = 32;
105 if (SDL_JoystickGetButton(joystick, i) == SDL_PRESSED) {
106 SDL_FillRect(screen, &area, 0xFFFF);
107 } else {
108 SDL_FillRect(screen, &area, 0x0000);
109 }
110 SDL_UpdateRects(screen, 1, &area);
111 }
112
113 /* Erase previous axes */
114 SDL_FillRect(screen, &axis_area[draw], 0x0000);
115
116 /* Draw the X/Y axis */
117 draw = !draw;
118 x = (((int)SDL_JoystickGetAxis(joystick, 0))+32768);
119 x *= SCREEN_WIDTH;
120 x /= 65535;
121 if ( x < 0 ) {
122 x = 0;
123 } else
124 if ( x > (SCREEN_WIDTH-16) ) {
125 x = SCREEN_WIDTH-16;
126 }
127 y = (((int)SDL_JoystickGetAxis(joystick, 1))+32768);
128 y *= SCREEN_HEIGHT;
129 y /= 65535;
130 if ( y < 0 ) {
131 y = 0;
132 } else
133 if ( y > (SCREEN_HEIGHT-16) ) {
134 y = SCREEN_HEIGHT-16;
135 }
136 axis_area[draw].x = (Sint16)x;
137 axis_area[draw].y = (Sint16)y;
138 axis_area[draw].w = 16;
139 axis_area[draw].h = 16;
140 SDL_FillRect(screen, &axis_area[draw], 0xFFFF);
141
142 SDL_UpdateRects(screen, 2, axis_area);
143 }
144 }
145
main(int argc,char * argv[])146 int main(int argc, char *argv[])
147 {
148 const char *name;
149 int i;
150 SDL_Joystick *joystick;
151
152 /* Initialize SDL (Note: video is required to start event loop) */
153 if ( SDL_Init(SDL_INIT_VIDEO|SDL_INIT_JOYSTICK) < 0 ) {
154 fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
155 exit(1);
156 }
157
158 /* Print information about the joysticks */
159 printf("There are %d joysticks attached\n", SDL_NumJoysticks());
160 for ( i=0; i<SDL_NumJoysticks(); ++i ) {
161 name = SDL_JoystickName(i);
162 printf("Joystick %d: %s\n",i,name ? name : "Unknown Joystick");
163 joystick = SDL_JoystickOpen(i);
164 if (joystick == NULL) {
165 fprintf(stderr, "SDL_JoystickOpen(%d) failed: %s\n", i, SDL_GetError());
166 } else {
167 printf(" axes: %d\n", SDL_JoystickNumAxes(joystick));
168 printf(" balls: %d\n", SDL_JoystickNumBalls(joystick));
169 printf(" hats: %d\n", SDL_JoystickNumHats(joystick));
170 printf(" buttons: %d\n", SDL_JoystickNumButtons(joystick));
171 SDL_JoystickClose(joystick);
172 }
173 }
174
175 if ( argv[1] ) {
176 joystick = SDL_JoystickOpen(atoi(argv[1]));
177 if ( joystick == NULL ) {
178 printf("Couldn't open joystick %d: %s\n", atoi(argv[1]),
179 SDL_GetError());
180 } else {
181 WatchJoystick(joystick);
182 SDL_JoystickClose(joystick);
183 }
184 }
185 SDL_QuitSubSystem(SDL_INIT_VIDEO|SDL_INIT_JOYSTICK);
186
187 return(0);
188 }
189