1/*
2    SDL - Simple DirectMedia Layer
3    Copyright (C) 1997-2012 Sam Lantinga
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9
10    This library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14
15    You should have received a copy of the GNU Lesser General Public
16    License along with this library; if not, write to the Free Software
17    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18
19    Sam Lantinga
20    slouken@libsdl.org
21*/
22
23/** @file SDL_joystick.h
24 *  Include file for SDL joystick event handling
25 */
26
27#ifndef _SDL_joystick_h
28#define _SDL_joystick_h
29
30#include "SDL_stdinc.h"
31#include "SDL_error.h"
32
33#include "begin_code.h"
34/* Set up for C function definitions, even when using C++ */
35#ifdef __cplusplus
36extern "C" {
37#endif
38
39/** @file SDL_joystick.h
40 *  @note In order to use these functions, SDL_Init() must have been called
41 *        with the SDL_INIT_JOYSTICK flag.  This causes SDL to scan the system
42 *        for joysticks, and load appropriate drivers.
43 */
44
45/** The joystick structure used to identify an SDL joystick */
46struct _SDL_Joystick;
47typedef struct _SDL_Joystick SDL_Joystick;
48
49/* Function prototypes */
50/**
51 * Count the number of joysticks attached to the system
52 */
53extern DECLSPEC int SDLCALL SDL_NumJoysticks(void);
54
55/**
56 * Get the implementation dependent name of a joystick.
57 *
58 * This can be called before any joysticks are opened.
59 * If no name can be found, this function returns NULL.
60 */
61extern DECLSPEC const char * SDLCALL SDL_JoystickName(int device_index);
62
63/**
64 * Open a joystick for use.
65 *
66 * @param[in] device_index
67 * The index passed as an argument refers to
68 * the N'th joystick on the system.  This index is the value which will
69 * identify this joystick in future joystick events.
70 *
71 * @return This function returns a joystick identifier, or NULL if an error occurred.
72 */
73extern DECLSPEC SDL_Joystick * SDLCALL SDL_JoystickOpen(int device_index);
74
75/**
76 * Returns 1 if the joystick has been opened, or 0 if it has not.
77 */
78extern DECLSPEC int SDLCALL SDL_JoystickOpened(int device_index);
79
80/**
81 * Get the device index of an opened joystick.
82 */
83extern DECLSPEC int SDLCALL SDL_JoystickIndex(SDL_Joystick *joystick);
84
85/**
86 * Get the number of general axis controls on a joystick
87 */
88extern DECLSPEC int SDLCALL SDL_JoystickNumAxes(SDL_Joystick *joystick);
89
90/**
91 * Get the number of trackballs on a joystick
92 *
93 * Joystick trackballs have only relative motion events associated
94 * with them and their state cannot be polled.
95 */
96extern DECLSPEC int SDLCALL SDL_JoystickNumBalls(SDL_Joystick *joystick);
97
98/**
99 * Get the number of POV hats on a joystick
100 */
101extern DECLSPEC int SDLCALL SDL_JoystickNumHats(SDL_Joystick *joystick);
102
103/**
104 * Get the number of buttons on a joystick
105 */
106extern DECLSPEC int SDLCALL SDL_JoystickNumButtons(SDL_Joystick *joystick);
107
108/**
109 * Update the current state of the open joysticks.
110 *
111 * This is called automatically by the event loop if any joystick
112 * events are enabled.
113 */
114extern DECLSPEC void SDLCALL SDL_JoystickUpdate(void);
115
116/**
117 * Enable/disable joystick event polling.
118 *
119 * If joystick events are disabled, you must call SDL_JoystickUpdate()
120 * yourself and check the state of the joystick when you want joystick
121 * information.
122 *
123 * @param[in] state The state can be one of SDL_QUERY, SDL_ENABLE or SDL_IGNORE.
124 */
125extern DECLSPEC int SDLCALL SDL_JoystickEventState(int state);
126
127/**
128 * Get the current state of an axis control on a joystick
129 *
130 * @param[in] axis The axis indices start at index 0.
131 *
132 * @return The state is a value ranging from -32768 to 32767.
133 */
134extern DECLSPEC Sint16 SDLCALL SDL_JoystickGetAxis(SDL_Joystick *joystick, int axis);
135
136/**
137 *  @name Hat Positions
138 *  The return value of SDL_JoystickGetHat() is one of the following positions:
139 */
140/*@{*/
141#define SDL_HAT_CENTERED	0x00
142#define SDL_HAT_UP		0x01
143#define SDL_HAT_RIGHT		0x02
144#define SDL_HAT_DOWN		0x04
145#define SDL_HAT_LEFT		0x08
146#define SDL_HAT_RIGHTUP		(SDL_HAT_RIGHT|SDL_HAT_UP)
147#define SDL_HAT_RIGHTDOWN	(SDL_HAT_RIGHT|SDL_HAT_DOWN)
148#define SDL_HAT_LEFTUP		(SDL_HAT_LEFT|SDL_HAT_UP)
149#define SDL_HAT_LEFTDOWN	(SDL_HAT_LEFT|SDL_HAT_DOWN)
150/*@}*/
151
152/**
153 *  Get the current state of a POV hat on a joystick
154 *
155 *  @param[in] hat The hat indices start at index 0.
156 */
157extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetHat(SDL_Joystick *joystick, int hat);
158
159/**
160 * Get the ball axis change since the last poll
161 *
162 * @param[in] ball The ball indices start at index 0.
163 *
164 * @return This returns 0, or -1 if you passed it invalid parameters.
165 */
166extern DECLSPEC int SDLCALL SDL_JoystickGetBall(SDL_Joystick *joystick, int ball, int *dx, int *dy);
167
168/**
169 * Get the current state of a button on a joystick
170 *
171 * @param[in] button The button indices start at index 0.
172 */
173extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetButton(SDL_Joystick *joystick, int button);
174
175/**
176 * Close a joystick previously opened with SDL_JoystickOpen()
177 */
178extern DECLSPEC void SDLCALL SDL_JoystickClose(SDL_Joystick *joystick);
179
180
181/* Ends C function definitions when using C++ */
182#ifdef __cplusplus
183}
184#endif
185#include "close_code.h"
186
187#endif /* _SDL_joystick_h */
188