This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
testjoystick.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
/*
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"
20
#include "common.h"
22
23
static CommonState *state;
static SDL_BlendMode blendMode = SDL_BLENDMODE_NONE;
25
26
27
#define MAX_NUM_AXES 6
#define MAX_NUM_HATS 2
28
29
30
31
32
33
34
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);
}
35
36
37
void
WatchJoystick(SDL_Joystick * joystick)
{
38
39
SDL_Window *window = NULL;
SDL_Renderer *screen = NULL;
40
41
42
SDL_Rect viewport;
SDL_Event event;
43
44
45
const char *name = NULL;
int done = 0;
int i;
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
/* Print info about the joystick we are watching */
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));
/* Loop, getting joystick events! */
while (!done) {
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:
done = 1;
break;
default:
break;
}
}
105
/* Update visual joystick state */
106
107
for (i = 0; i < state->num_windows; ++i) {
screen = state->renderers[i];
109
110
111
112
113
114
115
116
117
118
119
120
/* Erase previous axes */
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, SDL_ALPHA_OPAQUE);
SDL_RenderClear(screen);
/* Query the sizes */
SDL_RenderGetViewport(screen, &viewport);
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, viewport.h - 34, 32, 32);
}
121
122
}
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
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 *= viewport.w ;
x /= 65535;
if (x < 0) {
x = 0;
} else if (x > (viewport.w - 16)) {
x = viewport.w - 16;
}
y = (((int) SDL_JoystickGetAxis(joystick, i * 2 + 1)) + 32768);
y *= viewport.h;
y /= 65535;
if (y < 0) {
y = 0;
} else if (y > (viewport.h - 16)) {
y = viewport.h - 16;
}
144
DrawRect(screen, x, y, 16, 16);
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0xFF, SDL_ALPHA_OPAQUE);
for (i = 0; i < SDL_JoystickNumHats(joystick); ++i) {
/* Derive the new position */
int x = viewport.w/2;
int y = viewport.h/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 = viewport.h-8;
}
if (hat_pos & SDL_HAT_LEFT) {
x = 0;
} else if (hat_pos & SDL_HAT_RIGHT) {
x = viewport.w-8;
}
DrawRect(screen, x, y, 8, 8);
169
SDL_RenderPresent(screen);
170
171
172
173
174
175
176
177
}
}
}
int
main(int argc, char *argv[])
{
const char *name;
178
int i, joy=-1;
179
180
181
SDL_Joystick *joystick;
/* Initialize SDL (Note: video is required to start event loop) */
182
if (SDL_Init(SDL_INIT_JOYSTICK) < 0) {
183
184
185
186
fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
exit(1);
}
187
188
189
190
191
192
193
/* Initialize test framework */
state = CommonCreateState(argv, SDL_INIT_VIDEO | SDL_INIT_JOYSTICK);
if (!state) {
fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
return 1;
}
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/* Print information about the joysticks */
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");
joystick = SDL_JoystickOpen(i);
if (joystick == NULL) {
fprintf(stderr, "SDL_JoystickOpen(%d) failed: %s\n", i,
SDL_GetError());
} else {
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));
SDL_JoystickClose(joystick);
}
}
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
for (i = 1; i < argc;) {
int consumed;
consumed = CommonArg(state, i);
if (consumed == 0) {
consumed = -1;
if (SDL_isdigit(*argv[i])) {
joy = SDL_atoi(argv[i]);
consumed = 1;
}
}
if (consumed < 0) {
return 1;
}
i += consumed;
}
if (!CommonInit(state)) {
return 2;
}
if (joy > -1) {
joystick = SDL_JoystickOpen(joy);
234
if (joystick == NULL) {
235
printf("Couldn't open joystick %d: %s\n", joy,
236
237
238
239
240
241
SDL_GetError());
} else {
WatchJoystick(joystick);
SDL_JoystickClose(joystick);
}
}
242
243
SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
CommonQuit(state);
244
245
246
return (0);
}