/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga

    slouken@libsdl.org

*/

/** @file SDL_joystick.h

 *  Include file for SDL joystick event handling

 */

#ifndef _SDL_joystick_h

#define _SDL_joystick_h

#include "SDL_stdinc.h"

#include "SDL_error.h"

#include "begin_code.h"

/* Set up for C function definitions, even when using C++ */

#ifdef __cplusplus

extern "C" {

#endif

/** @file SDL_joystick.h

 *  @note In order to use these functions, SDL_Init() must have been called

 *        with the SDL_INIT_JOYSTICK flag.  This causes SDL to scan the system

 *        for joysticks, and load appropriate drivers.

 */

/** The joystick structure used to identify an SDL joystick */

struct _SDL_Joystick;

typedef struct _SDL_Joystick SDL_Joystick;

/* Function prototypes */

/**

 * Count the number of joysticks attached to the system

 */

extern DECLSPEC int SDLCALL SDL_NumJoysticks(void);

/**

 * Get the implementation dependent name of a joystick.

 *

 * This can be called before any joysticks are opened.

 * If no name can be found, this function returns NULL.

 */

extern DECLSPEC const char * SDLCALL SDL_JoystickName(int device_index);

/**

 * Open a joystick for use.

 *

 * @param[in] device_index

 * The index passed as an argument refers to

 * the N'th joystick on the system.  This index is the value which will

 * identify this joystick in future joystick events.

 *

 * @return This function returns a joystick identifier, or NULL if an error occurred.

 */

extern DECLSPEC SDL_Joystick * SDLCALL SDL_JoystickOpen(int device_index);

/**

 * Returns 1 if the joystick has been opened, or 0 if it has not.

 */

extern DECLSPEC int SDLCALL SDL_JoystickOpened(int device_index);

/**

 * Get the device index of an opened joystick.

 */

extern DECLSPEC int SDLCALL SDL_JoystickIndex(SDL_Joystick *joystick);

/**

 * Get the number of general axis controls on a joystick

 */

extern DECLSPEC int SDLCALL SDL_JoystickNumAxes(SDL_Joystick *joystick);

/**

 * Get the number of trackballs on a joystick

 *

 * Joystick trackballs have only relative motion events associated

 * with them and their state cannot be polled.

 */

extern DECLSPEC int SDLCALL SDL_JoystickNumBalls(SDL_Joystick *joystick);

/**

 * Get the number of POV hats on a joystick

 */

extern DECLSPEC int SDLCALL SDL_JoystickNumHats(SDL_Joystick *joystick);

/**

 * Get the number of buttons on a joystick

 */

extern DECLSPEC int SDLCALL SDL_JoystickNumButtons(SDL_Joystick *joystick);

/**

 * Update the current state of the open joysticks.

 *

 * This is called automatically by the event loop if any joystick

 * events are enabled.

 */

extern DECLSPEC void SDLCALL SDL_JoystickUpdate(void);

/**

 * Enable/disable joystick event polling.

 *

 * If joystick events are disabled, you must call SDL_JoystickUpdate()

 * yourself and check the state of the joystick when you want joystick

 * information.

 *

 * @param[in] state The state can be one of SDL_QUERY, SDL_ENABLE or SDL_IGNORE.

 */

extern DECLSPEC int SDLCALL SDL_JoystickEventState(int state);

/**

 * Get the current state of an axis control on a joystick

 *

 * @param[in] axis The axis indices start at index 0.

 *

 * @return The state is a value ranging from -32768 to 32767.

 */

extern DECLSPEC Sint16 SDLCALL SDL_JoystickGetAxis(SDL_Joystick *joystick, int axis);

/**

 *  @name Hat Positions

 *  The return value of SDL_JoystickGetHat() is one of the following positions:

 */

/*@{*/

#define SDL_HAT_CENTERED	0x00

#define SDL_HAT_UP		0x01

#define SDL_HAT_RIGHT		0x02

#define SDL_HAT_DOWN		0x04

#define SDL_HAT_LEFT		0x08

#define SDL_HAT_RIGHTUP		(SDL_HAT_RIGHT|SDL_HAT_UP)

#define SDL_HAT_RIGHTDOWN	(SDL_HAT_RIGHT|SDL_HAT_DOWN)

#define SDL_HAT_LEFTUP		(SDL_HAT_LEFT|SDL_HAT_UP)

#define SDL_HAT_LEFTDOWN	(SDL_HAT_LEFT|SDL_HAT_DOWN)

/*@}*/

/** 

 *  Get the current state of a POV hat on a joystick

 *

 *  @param[in] hat The hat indices start at index 0.

 */

extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetHat(SDL_Joystick *joystick, int hat);

/**

 * Get the ball axis change since the last poll

 *

 * @param[in] ball The ball indices start at index 0.

 *

 * @return This returns 0, or -1 if you passed it invalid parameters.

 */

extern DECLSPEC int SDLCALL SDL_JoystickGetBall(SDL_Joystick *joystick, int ball, int *dx, int *dy);

/**

 * Get the current state of a button on a joystick

 *

 * @param[in] button The button indices start at index 0.

 */

extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetButton(SDL_Joystick *joystick, int button);

/**

 * Close a joystick previously opened with SDL_JoystickOpen()

 */

extern DECLSPEC void SDLCALL SDL_JoystickClose(SDL_Joystick *joystick);

/* Ends C function definitions when using C++ */

#ifdef __cplusplus

}

#endif

#include "close_code.h"

#endif /* _SDL_joystick_h */