include/SDL_joystick.h
author Ryan C. Gordon <icculus@icculus.org>
Sat, 14 Nov 2015 12:35:45 -0500
changeset 9916 9429bc102632
parent 9884 26b595dea221
child 9917 450a2f6e2bf2
permissions -rw-r--r--
Added SDL_JoystickFromInstanceID() and SDL_GameControllerFromInstanceID().
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 /**
    23  *  \file SDL_joystick.h
    24  *
    25  *  Include file for SDL joystick event handling
    26  *
    27  * The term "device_index" identifies currently plugged in joystick devices between 0 and SDL_NumJoysticks, with the exact joystick
    28  *   behind a device_index changing as joysticks are plugged and unplugged.
    29  *
    30  * The term "instance_id" is the current instantiation of a joystick device in the system, if the joystick is removed and then re-inserted
    31  *   then it will get a new instance_id, instance_id's are monotonically increasing identifiers of a joystick plugged in.
    32  *
    33  * The term JoystickGUID is a stable 128-bit identifier for a joystick device that does not change over time, it identifies class of
    34  *   the device (a X360 wired controller for example). This identifier is platform dependent.
    35  *
    36  *
    37  */
    38 
    39 #ifndef _SDL_joystick_h
    40 #define _SDL_joystick_h
    41 
    42 #include "SDL_stdinc.h"
    43 #include "SDL_error.h"
    44 
    45 #include "begin_code.h"
    46 /* Set up for C function definitions, even when using C++ */
    47 #ifdef __cplusplus
    48 extern "C" {
    49 #endif
    50 
    51 /**
    52  *  \file SDL_joystick.h
    53  *
    54  *  In order to use these functions, SDL_Init() must have been called
    55  *  with the ::SDL_INIT_JOYSTICK flag.  This causes SDL to scan the system
    56  *  for joysticks, and load appropriate drivers.
    57  *
    58  *  If you would like to receive joystick updates while the application
    59  *  is in the background, you should set the following hint before calling
    60  *  SDL_Init(): SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS
    61  */
    62 
    63 /* The joystick structure used to identify an SDL joystick */
    64 struct _SDL_Joystick;
    65 typedef struct _SDL_Joystick SDL_Joystick;
    66 
    67 /* A structure that encodes the stable unique id for a joystick device */
    68 typedef struct {
    69     Uint8 data[16];
    70 } SDL_JoystickGUID;
    71 
    72 typedef Sint32 SDL_JoystickID;
    73 
    74 typedef enum
    75 {
    76     SDL_JOYSTICK_POWER_UNKNOWN = -1,
    77     SDL_JOYSTICK_POWER_EMPTY,
    78     SDL_JOYSTICK_POWER_LOW,
    79     SDL_JOYSTICK_POWER_MEDIUM,
    80     SDL_JOYSTICK_POWER_FULL,
    81     SDL_JOYSTICK_POWER_WIRED,
    82     SDL_JOYSTICK_POWER_MAX
    83 } SDL_JoystickPowerLevel;
    84 
    85 /* Function prototypes */
    86 /**
    87  *  Count the number of joysticks attached to the system right now
    88  */
    89 extern DECLSPEC int SDLCALL SDL_NumJoysticks(void);
    90 
    91 /**
    92  *  Get the implementation dependent name of a joystick.
    93  *  This can be called before any joysticks are opened.
    94  *  If no name can be found, this function returns NULL.
    95  */
    96 extern DECLSPEC const char *SDLCALL SDL_JoystickNameForIndex(int device_index);
    97 
    98 /**
    99  *  Open a joystick for use.
   100  *  The index passed as an argument refers to the N'th joystick on the system.
   101  *  This index is not the value which will identify this joystick in future
   102  *  joystick events.  The joystick's instance id (::SDL_JoystickID) will be used
   103  *  there instead.
   104  *
   105  *  \return A joystick identifier, or NULL if an error occurred.
   106  */
   107 extern DECLSPEC SDL_Joystick *SDLCALL SDL_JoystickOpen(int device_index);
   108 
   109 /**
   110  * Return the SDL_Joystick associated with an instance id.
   111  */
   112 extern DECLSPEC SDL_Joystick *SDLCALL SDL_JoystickFromInstanceID(SDL_JoystickID joyid);
   113 
   114 /**
   115  *  Return the name for this currently opened joystick.
   116  *  If no name can be found, this function returns NULL.
   117  */
   118 extern DECLSPEC const char *SDLCALL SDL_JoystickName(SDL_Joystick * joystick);
   119 
   120 /**
   121  *  Return the GUID for the joystick at this index
   122  */
   123 extern DECLSPEC SDL_JoystickGUID SDLCALL SDL_JoystickGetDeviceGUID(int device_index);
   124 
   125 /**
   126  *  Return the GUID for this opened joystick
   127  */
   128 extern DECLSPEC SDL_JoystickGUID SDLCALL SDL_JoystickGetGUID(SDL_Joystick * joystick);
   129 
   130 /**
   131  *  Return a string representation for this guid. pszGUID must point to at least 33 bytes
   132  *  (32 for the string plus a NULL terminator).
   133  */
   134 extern DECLSPEC void SDLCALL SDL_JoystickGetGUIDString(SDL_JoystickGUID guid, char *pszGUID, int cbGUID);
   135 
   136 /**
   137  *  convert a string into a joystick formatted guid
   138  */
   139 extern DECLSPEC SDL_JoystickGUID SDLCALL SDL_JoystickGetGUIDFromString(const char *pchGUID);
   140 
   141 /**
   142  *  Returns SDL_TRUE if the joystick has been opened and currently connected, or SDL_FALSE if it has not.
   143  */
   144 extern DECLSPEC SDL_bool SDLCALL SDL_JoystickGetAttached(SDL_Joystick * joystick);
   145 
   146 /**
   147  *  Get the instance ID of an opened joystick or -1 if the joystick is invalid.
   148  */
   149 extern DECLSPEC SDL_JoystickID SDLCALL SDL_JoystickInstanceID(SDL_Joystick * joystick);
   150 
   151 /**
   152  *  Get the number of general axis controls on a joystick.
   153  */
   154 extern DECLSPEC int SDLCALL SDL_JoystickNumAxes(SDL_Joystick * joystick);
   155 
   156 /**
   157  *  Get the number of trackballs on a joystick.
   158  *
   159  *  Joystick trackballs have only relative motion events associated
   160  *  with them and their state cannot be polled.
   161  */
   162 extern DECLSPEC int SDLCALL SDL_JoystickNumBalls(SDL_Joystick * joystick);
   163 
   164 /**
   165  *  Get the number of POV hats on a joystick.
   166  */
   167 extern DECLSPEC int SDLCALL SDL_JoystickNumHats(SDL_Joystick * joystick);
   168 
   169 /**
   170  *  Get the number of buttons on a joystick.
   171  */
   172 extern DECLSPEC int SDLCALL SDL_JoystickNumButtons(SDL_Joystick * joystick);
   173 
   174 /**
   175  *  Update the current state of the open joysticks.
   176  *
   177  *  This is called automatically by the event loop if any joystick
   178  *  events are enabled.
   179  */
   180 extern DECLSPEC void SDLCALL SDL_JoystickUpdate(void);
   181 
   182 /**
   183  *  Enable/disable joystick event polling.
   184  *
   185  *  If joystick events are disabled, you must call SDL_JoystickUpdate()
   186  *  yourself and check the state of the joystick when you want joystick
   187  *  information.
   188  *
   189  *  The state can be one of ::SDL_QUERY, ::SDL_ENABLE or ::SDL_IGNORE.
   190  */
   191 extern DECLSPEC int SDLCALL SDL_JoystickEventState(int state);
   192 
   193 /**
   194  *  Get the current state of an axis control on a joystick.
   195  *
   196  *  The state is a value ranging from -32768 to 32767.
   197  *
   198  *  The axis indices start at index 0.
   199  */
   200 extern DECLSPEC Sint16 SDLCALL SDL_JoystickGetAxis(SDL_Joystick * joystick,
   201                                                    int axis);
   202 
   203 /**
   204  *  \name Hat positions
   205  */
   206 /* @{ */
   207 #define SDL_HAT_CENTERED    0x00
   208 #define SDL_HAT_UP          0x01
   209 #define SDL_HAT_RIGHT       0x02
   210 #define SDL_HAT_DOWN        0x04
   211 #define SDL_HAT_LEFT        0x08
   212 #define SDL_HAT_RIGHTUP     (SDL_HAT_RIGHT|SDL_HAT_UP)
   213 #define SDL_HAT_RIGHTDOWN   (SDL_HAT_RIGHT|SDL_HAT_DOWN)
   214 #define SDL_HAT_LEFTUP      (SDL_HAT_LEFT|SDL_HAT_UP)
   215 #define SDL_HAT_LEFTDOWN    (SDL_HAT_LEFT|SDL_HAT_DOWN)
   216 /* @} */
   217 
   218 /**
   219  *  Get the current state of a POV hat on a joystick.
   220  *
   221  *  The hat indices start at index 0.
   222  *
   223  *  \return The return value is one of the following positions:
   224  *           - ::SDL_HAT_CENTERED
   225  *           - ::SDL_HAT_UP
   226  *           - ::SDL_HAT_RIGHT
   227  *           - ::SDL_HAT_DOWN
   228  *           - ::SDL_HAT_LEFT
   229  *           - ::SDL_HAT_RIGHTUP
   230  *           - ::SDL_HAT_RIGHTDOWN
   231  *           - ::SDL_HAT_LEFTUP
   232  *           - ::SDL_HAT_LEFTDOWN
   233  */
   234 extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetHat(SDL_Joystick * joystick,
   235                                                  int hat);
   236 
   237 /**
   238  *  Get the ball axis change since the last poll.
   239  *
   240  *  \return 0, or -1 if you passed it invalid parameters.
   241  *
   242  *  The ball indices start at index 0.
   243  */
   244 extern DECLSPEC int SDLCALL SDL_JoystickGetBall(SDL_Joystick * joystick,
   245                                                 int ball, int *dx, int *dy);
   246 
   247 /**
   248  *  Get the current state of a button on a joystick.
   249  *
   250  *  The button indices start at index 0.
   251  */
   252 extern DECLSPEC Uint8 SDLCALL SDL_JoystickGetButton(SDL_Joystick * joystick,
   253                                                     int button);
   254 
   255 /**
   256  *  Close a joystick previously opened with SDL_JoystickOpen().
   257  */
   258 extern DECLSPEC void SDLCALL SDL_JoystickClose(SDL_Joystick * joystick);
   259 
   260 /**
   261 *  Return the battery level of this joystick
   262 */
   263 extern DECLSPEC SDL_JoystickPowerLevel SDLCALL SDL_JoystickCurrentPowerLevel(SDL_Joystick * joystick);
   264 
   265 
   266 /* Ends C function definitions when using C++ */
   267 #ifdef __cplusplus
   268 }
   269 #endif
   270 #include "close_code.h"
   271 
   272 #endif /* _SDL_joystick_h */
   273 
   274 /* vi: set ts=4 sw=4 expandtab: */