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
13void 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
146int 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