src/joystick/windows/SDL_xinputjoystick.c - third_party/sdl - Git at Google

 /*
   Simple DirectMedia Layer
   Copyright (C) 1997-2016 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, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must not
      claim that you wrote the original software. If you use this software
      in a product, an acknowledgment in the product documentation would be
      appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must not be
      misrepresented as being the original software.
   3. This notice may not be removed or altered from any source distribution.
 */
 #include "../../SDL_internal.h"

 #include "../SDL_sysjoystick.h"

 #if SDL_JOYSTICK_XINPUT

 #include "SDL_assert.h"
 #include "SDL_hints.h"
 #include "SDL_windowsjoystick_c.h"
 #include "SDL_xinputjoystick_c.h"

 /*
  * Internal stuff.
  */
 static SDL_bool s_bXInputEnabled = SDL_TRUE;


 static SDL_bool
 SDL_XInputUseOldJoystickMapping()
 {
     static int s_XInputUseOldJoystickMapping = -1;
     if (s_XInputUseOldJoystickMapping < 0) {
         s_XInputUseOldJoystickMapping = SDL_GetHintBoolean(SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING, SDL_FALSE);
     }
     return (s_XInputUseOldJoystickMapping > 0);
 }

 SDL_bool SDL_XINPUT_Enabled(void)
 {
     return s_bXInputEnabled;
 }

 int
 SDL_XINPUT_JoystickInit(void)
 {
     s_bXInputEnabled = SDL_GetHintBoolean(SDL_HINT_XINPUT_ENABLED, SDL_TRUE);

     if (s_bXInputEnabled && WIN_LoadXInputDLL() < 0) {
         s_bXInputEnabled = SDL_FALSE;  /* oh well. */
     }
     return 0;
 }

 static char *
 GetXInputName(const Uint8 userid, BYTE SubType)
 {
     char name[32];

     if (SDL_XInputUseOldJoystickMapping()) {
         SDL_snprintf(name, sizeof(name), "X360 Controller #%u", 1 + userid);
     } else {
         switch (SubType) {
         case XINPUT_DEVSUBTYPE_GAMEPAD:
             SDL_snprintf(name, sizeof(name), "XInput Controller #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_WHEEL:
             SDL_snprintf(name, sizeof(name), "XInput Wheel #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_ARCADE_STICK:
             SDL_snprintf(name, sizeof(name), "XInput ArcadeStick #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_FLIGHT_STICK:
             SDL_snprintf(name, sizeof(name), "XInput FlightStick #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_DANCE_PAD:
             SDL_snprintf(name, sizeof(name), "XInput DancePad #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_GUITAR:
         case XINPUT_DEVSUBTYPE_GUITAR_ALTERNATE:
         case XINPUT_DEVSUBTYPE_GUITAR_BASS:
             SDL_snprintf(name, sizeof(name), "XInput Guitar #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_DRUM_KIT:
             SDL_snprintf(name, sizeof(name), "XInput DrumKit #%u", 1 + userid);
             break;
         case XINPUT_DEVSUBTYPE_ARCADE_PAD:
             SDL_snprintf(name, sizeof(name), "XInput ArcadePad #%u", 1 + userid);
             break;
         default:
             SDL_snprintf(name, sizeof(name), "XInput Device #%u", 1 + userid);
             break;
         }
     }
     return SDL_strdup(name);
 }

 static void
 AddXInputDevice(const Uint8 userid, BYTE SubType, JoyStick_DeviceData **pContext)
 {
     JoyStick_DeviceData *pPrevJoystick = NULL;
     JoyStick_DeviceData *pNewJoystick = *pContext;

     if (SDL_XInputUseOldJoystickMapping() && SubType != XINPUT_DEVSUBTYPE_GAMEPAD)
         return;

     if (SubType == XINPUT_DEVSUBTYPE_UNKNOWN)
         return;

     while (pNewJoystick) {
         if (pNewJoystick->bXInputDevice && (pNewJoystick->XInputUserId == userid) && (pNewJoystick->SubType == SubType)) {
             /* if we are replacing the front of the list then update it */
             if (pNewJoystick == *pContext) {
                 *pContext = pNewJoystick->pNext;
             } else if (pPrevJoystick) {
                 pPrevJoystick->pNext = pNewJoystick->pNext;
             }

             pNewJoystick->pNext = SYS_Joystick;
             SYS_Joystick = pNewJoystick;
             return;   /* already in the list. */
         }

         pPrevJoystick = pNewJoystick;
         pNewJoystick = pNewJoystick->pNext;
     }

     pNewJoystick = (JoyStick_DeviceData *)SDL_malloc(sizeof(JoyStick_DeviceData));
     if (!pNewJoystick) {
         return; /* better luck next time? */
     }
     SDL_zerop(pNewJoystick);

     pNewJoystick->joystickname = GetXInputName(userid, SubType);
     if (!pNewJoystick->joystickname) {
         SDL_free(pNewJoystick);
         return; /* better luck next time? */
     }

     pNewJoystick->bXInputDevice = SDL_TRUE;
     if (SDL_XInputUseOldJoystickMapping()) {
         SDL_zero(pNewJoystick->guid);
     } else {
         pNewJoystick->guid.data[0] = 'x';
         pNewJoystick->guid.data[1] = 'i';
         pNewJoystick->guid.data[2] = 'n';
         pNewJoystick->guid.data[3] = 'p';
         pNewJoystick->guid.data[4] = 'u';
         pNewJoystick->guid.data[5] = 't';
         pNewJoystick->guid.data[6] = SubType;
     }
     pNewJoystick->SubType = SubType;
     pNewJoystick->XInputUserId = userid;
     SDL_SYS_AddJoystickDevice(pNewJoystick);
 }

 void
 SDL_XINPUT_JoystickDetect(JoyStick_DeviceData **pContext)
 {
     int iuserid;

     if (!s_bXInputEnabled) {
         return;
     }

     /* iterate in reverse, so these are in the final list in ascending numeric order. */
     for (iuserid = XUSER_MAX_COUNT - 1; iuserid >= 0; iuserid--) {
         const Uint8 userid = (Uint8)iuserid;
         XINPUT_CAPABILITIES capabilities;
         if (XINPUTGETCAPABILITIES(userid, XINPUT_FLAG_GAMEPAD, &capabilities) == ERROR_SUCCESS) {
             AddXInputDevice(userid, capabilities.SubType, pContext);
         }
     }
 }

 int
 SDL_XINPUT_JoystickOpen(SDL_Joystick * joystick, JoyStick_DeviceData *joystickdevice)
 {
     const Uint8 userId = joystickdevice->XInputUserId;
     XINPUT_CAPABILITIES capabilities;
     XINPUT_VIBRATION state;

     SDL_assert(s_bXInputEnabled);
     SDL_assert(XINPUTGETCAPABILITIES);
     SDL_assert(XINPUTSETSTATE);
     SDL_assert(userId < XUSER_MAX_COUNT);

     joystick->hwdata->bXInputDevice = SDL_TRUE;

     if (XINPUTGETCAPABILITIES(userId, XINPUT_FLAG_GAMEPAD, &capabilities) != ERROR_SUCCESS) {
         SDL_free(joystick->hwdata);
         joystick->hwdata = NULL;
         return SDL_SetError("Failed to obtain XInput device capabilities. Device disconnected?");
     }
     SDL_zero(state);
     joystick->hwdata->bXInputHaptic = (XINPUTSETSTATE(userId, &state) == ERROR_SUCCESS);
     joystick->hwdata->userid = userId;

     /* The XInput API has a hard coded button/axis mapping, so we just match it */
     if (SDL_XInputUseOldJoystickMapping()) {
         joystick->naxes = 6;
         joystick->nbuttons = 15;
     } else {
         joystick->naxes = 6;
         joystick->nbuttons = 11;
         joystick->nhats = 1;
     }
     return 0;
 }

 static void
 UpdateXInputJoystickBatteryInformation(SDL_Joystick * joystick, XINPUT_BATTERY_INFORMATION_EX *pBatteryInformation)
 {
     if ( pBatteryInformation->BatteryType != BATTERY_TYPE_UNKNOWN )
     {
         SDL_JoystickPowerLevel ePowerLevel = SDL_JOYSTICK_POWER_UNKNOWN;
         if (pBatteryInformation->BatteryType == BATTERY_TYPE_WIRED) {
             ePowerLevel = SDL_JOYSTICK_POWER_WIRED;
         } else {
             switch ( pBatteryInformation->BatteryLevel )
             {
             case BATTERY_LEVEL_EMPTY:
                 ePowerLevel = SDL_JOYSTICK_POWER_EMPTY;
                 break;
             case BATTERY_LEVEL_LOW:
                 ePowerLevel = SDL_JOYSTICK_POWER_LOW;
                 break;
             case BATTERY_LEVEL_MEDIUM:
                 ePowerLevel = SDL_JOYSTICK_POWER_MEDIUM;
                 break;
             default:
             case BATTERY_LEVEL_FULL:
                 ePowerLevel = SDL_JOYSTICK_POWER_FULL;
                 break;
             }
         }

         SDL_PrivateJoystickBatteryLevel( joystick, ePowerLevel );
     }
 }

 static void
 UpdateXInputJoystickState_OLD(SDL_Joystick * joystick, XINPUT_STATE_EX *pXInputState, XINPUT_BATTERY_INFORMATION_EX *pBatteryInformation)
 {
     static WORD s_XInputButtons[] = {
         XINPUT_GAMEPAD_DPAD_UP, XINPUT_GAMEPAD_DPAD_DOWN, XINPUT_GAMEPAD_DPAD_LEFT, XINPUT_GAMEPAD_DPAD_RIGHT,
         XINPUT_GAMEPAD_START, XINPUT_GAMEPAD_BACK, XINPUT_GAMEPAD_LEFT_THUMB, XINPUT_GAMEPAD_RIGHT_THUMB,
         XINPUT_GAMEPAD_LEFT_SHOULDER, XINPUT_GAMEPAD_RIGHT_SHOULDER,
         XINPUT_GAMEPAD_A, XINPUT_GAMEPAD_B, XINPUT_GAMEPAD_X, XINPUT_GAMEPAD_Y,
         XINPUT_GAMEPAD_GUIDE
     };
     WORD wButtons = pXInputState->Gamepad.wButtons;
     Uint8 button;

     SDL_PrivateJoystickAxis(joystick, 0, (Sint16)pXInputState->Gamepad.sThumbLX);
     SDL_PrivateJoystickAxis(joystick, 1, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbLY)));
     SDL_PrivateJoystickAxis(joystick, 2, (Sint16)pXInputState->Gamepad.sThumbRX);
     SDL_PrivateJoystickAxis(joystick, 3, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbRY)));
     SDL_PrivateJoystickAxis(joystick, 4, (Sint16)(((int)pXInputState->Gamepad.bLeftTrigger * 65535 / 255) - 32768));
     SDL_PrivateJoystickAxis(joystick, 5, (Sint16)(((int)pXInputState->Gamepad.bRightTrigger * 65535 / 255) - 32768));

     for (button = 0; button < SDL_arraysize(s_XInputButtons); ++button) {
         SDL_PrivateJoystickButton(joystick, button, (wButtons & s_XInputButtons[button]) ? SDL_PRESSED : SDL_RELEASED);
     }

     UpdateXInputJoystickBatteryInformation( joystick, pBatteryInformation );
 }

 static void
 UpdateXInputJoystickState(SDL_Joystick * joystick, XINPUT_STATE_EX *pXInputState, XINPUT_BATTERY_INFORMATION_EX *pBatteryInformation)
 {
     static WORD s_XInputButtons[] = {
         XINPUT_GAMEPAD_A, XINPUT_GAMEPAD_B, XINPUT_GAMEPAD_X, XINPUT_GAMEPAD_Y,
         XINPUT_GAMEPAD_LEFT_SHOULDER, XINPUT_GAMEPAD_RIGHT_SHOULDER, XINPUT_GAMEPAD_BACK, XINPUT_GAMEPAD_START,
         XINPUT_GAMEPAD_LEFT_THUMB, XINPUT_GAMEPAD_RIGHT_THUMB,
         XINPUT_GAMEPAD_GUIDE
     };
     WORD wButtons = pXInputState->Gamepad.wButtons;
     Uint8 button;
     Uint8 hat = SDL_HAT_CENTERED;

     SDL_PrivateJoystickAxis(joystick, 0, (Sint16)pXInputState->Gamepad.sThumbLX);
     SDL_PrivateJoystickAxis(joystick, 1, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbLY)));
     SDL_PrivateJoystickAxis(joystick, 2, (Sint16)(((int)pXInputState->Gamepad.bLeftTrigger * 65535 / 255) - 32768));
     SDL_PrivateJoystickAxis(joystick, 3, (Sint16)pXInputState->Gamepad.sThumbRX);
     SDL_PrivateJoystickAxis(joystick, 4, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbRY)));
     SDL_PrivateJoystickAxis(joystick, 5, (Sint16)(((int)pXInputState->Gamepad.bRightTrigger * 65535 / 255) - 32768));

     for (button = 0; button < SDL_arraysize(s_XInputButtons); ++button) {
         SDL_PrivateJoystickButton(joystick, button, (wButtons & s_XInputButtons[button]) ? SDL_PRESSED : SDL_RELEASED);
     }

     if (wButtons & XINPUT_GAMEPAD_DPAD_UP) {
         hat |= SDL_HAT_UP;
     }
     if (wButtons & XINPUT_GAMEPAD_DPAD_DOWN) {
         hat |= SDL_HAT_DOWN;
     }
     if (wButtons & XINPUT_GAMEPAD_DPAD_LEFT) {
         hat |= SDL_HAT_LEFT;
     }
     if (wButtons & XINPUT_GAMEPAD_DPAD_RIGHT) {
         hat |= SDL_HAT_RIGHT;
     }
     SDL_PrivateJoystickHat(joystick, 0, hat);

     UpdateXInputJoystickBatteryInformation( joystick, pBatteryInformation );
 }

 void
 SDL_XINPUT_JoystickUpdate(SDL_Joystick * joystick)
 {
     HRESULT result;
     XINPUT_STATE_EX XInputState;
     XINPUT_BATTERY_INFORMATION_EX XBatteryInformation;

     if (!XINPUTGETSTATE)
         return;

     result = XINPUTGETSTATE(joystick->hwdata->userid, &XInputState);
     if (result == ERROR_DEVICE_NOT_CONNECTED) {
         joystick->hwdata->send_remove_event = SDL_TRUE;
         joystick->hwdata->removed = SDL_TRUE;
         return;
     }

     SDL_zero( XBatteryInformation );
     if ( XINPUTGETBATTERYINFORMATION )
     {
         result = XINPUTGETBATTERYINFORMATION( joystick->hwdata->userid, BATTERY_DEVTYPE_GAMEPAD, &XBatteryInformation );
     }

     /* only fire events if the data changed from last time */
     if (XInputState.dwPacketNumber && XInputState.dwPacketNumber != joystick->hwdata->dwPacketNumber) {
         if (SDL_XInputUseOldJoystickMapping()) {
             UpdateXInputJoystickState_OLD(joystick, &XInputState, &XBatteryInformation);
         } else {
             UpdateXInputJoystickState(joystick, &XInputState, &XBatteryInformation);
         }
         joystick->hwdata->dwPacketNumber = XInputState.dwPacketNumber;
     }
 }

 void
 SDL_XINPUT_JoystickClose(SDL_Joystick * joystick)
 {
 }

 void
 SDL_XINPUT_JoystickQuit(void)
 {
     if (s_bXInputEnabled) {
         WIN_UnloadXInputDLL();
     }
 }

 SDL_bool
 SDL_SYS_IsXInputGamepad_DeviceIndex(int device_index)
 {
     JoyStick_DeviceData *device = SYS_Joystick;
     int index;

     for (index = device_index; index > 0; index--)
         device = device->pNext;

     return device->bXInputDevice;
 }

 #else /* !SDL_JOYSTICK_XINPUT */

 typedef struct JoyStick_DeviceData JoyStick_DeviceData;

 SDL_bool SDL_XINPUT_Enabled(void)
 {
     return SDL_FALSE;
 }

 int
 SDL_XINPUT_JoystickInit(void)
 {
     return 0;
 }

 void
 SDL_XINPUT_JoystickDetect(JoyStick_DeviceData **pContext)
 {
 }

 int
 SDL_XINPUT_JoystickOpen(SDL_Joystick * joystick, JoyStick_DeviceData *joystickdevice)
 {
     return SDL_Unsupported();
 }

 void
 SDL_XINPUT_JoystickUpdate(SDL_Joystick * joystick)
 {
 }

 void
 SDL_XINPUT_JoystickClose(SDL_Joystick * joystick)
 {
 }

 void
 SDL_XINPUT_JoystickQuit(void)
 {
 }

 #endif /* SDL_JOYSTICK_XINPUT */

 /* vi: set ts=4 sw=4 expandtab: */
	/*
	Simple DirectMedia Layer
	Copyright (C) 1997-2016 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, subject to the following restrictions:

	1. The origin of this software must not be misrepresented; you must not
	claim that you wrote the original software. If you use this software
	in a product, an acknowledgment in the product documentation would be
	appreciated but is not required.
	2. Altered source versions must be plainly marked as such, and must not be
	misrepresented as being the original software.
	3. This notice may not be removed or altered from any source distribution.
	*/
	#include "../../SDL_internal.h"

	#include "../SDL_sysjoystick.h"

	#if SDL_JOYSTICK_XINPUT

	#include "SDL_assert.h"
	#include "SDL_hints.h"
	#include "SDL_windowsjoystick_c.h"
	#include "SDL_xinputjoystick_c.h"

	/*
	* Internal stuff.
	*/
	static SDL_bool s_bXInputEnabled = SDL_TRUE;


	static SDL_bool
	SDL_XInputUseOldJoystickMapping()
	{
	static int s_XInputUseOldJoystickMapping = -1;
	if (s_XInputUseOldJoystickMapping < 0) {
	s_XInputUseOldJoystickMapping = SDL_GetHintBoolean(SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING, SDL_FALSE);
	}
	return (s_XInputUseOldJoystickMapping > 0);
	}

	SDL_bool SDL_XINPUT_Enabled(void)
	{
	return s_bXInputEnabled;
	}

	int
	SDL_XINPUT_JoystickInit(void)
	{
	s_bXInputEnabled = SDL_GetHintBoolean(SDL_HINT_XINPUT_ENABLED, SDL_TRUE);

	if (s_bXInputEnabled && WIN_LoadXInputDLL() < 0) {
	s_bXInputEnabled = SDL_FALSE; /* oh well. */
	}
	return 0;
	}

	static char *
	GetXInputName(const Uint8 userid, BYTE SubType)
	{
	char name[32];

	if (SDL_XInputUseOldJoystickMapping()) {
	SDL_snprintf(name, sizeof(name), "X360 Controller #%u", 1 + userid);
	} else {
	switch (SubType) {
	case XINPUT_DEVSUBTYPE_GAMEPAD:
	SDL_snprintf(name, sizeof(name), "XInput Controller #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_WHEEL:
	SDL_snprintf(name, sizeof(name), "XInput Wheel #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_ARCADE_STICK:
	SDL_snprintf(name, sizeof(name), "XInput ArcadeStick #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_FLIGHT_STICK:
	SDL_snprintf(name, sizeof(name), "XInput FlightStick #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_DANCE_PAD:
	SDL_snprintf(name, sizeof(name), "XInput DancePad #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_GUITAR:
	case XINPUT_DEVSUBTYPE_GUITAR_ALTERNATE:
	case XINPUT_DEVSUBTYPE_GUITAR_BASS:
	SDL_snprintf(name, sizeof(name), "XInput Guitar #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_DRUM_KIT:
	SDL_snprintf(name, sizeof(name), "XInput DrumKit #%u", 1 + userid);
	break;
	case XINPUT_DEVSUBTYPE_ARCADE_PAD:
	SDL_snprintf(name, sizeof(name), "XInput ArcadePad #%u", 1 + userid);
	break;
	default:
	SDL_snprintf(name, sizeof(name), "XInput Device #%u", 1 + userid);
	break;
	}
	}
	return SDL_strdup(name);
	}

	static void
	AddXInputDevice(const Uint8 userid, BYTE SubType, JoyStick_DeviceData **pContext)
	{
	JoyStick_DeviceData *pPrevJoystick = NULL;
	JoyStick_DeviceData pNewJoystick = pContext;

	if (SDL_XInputUseOldJoystickMapping() && SubType != XINPUT_DEVSUBTYPE_GAMEPAD)
	return;

	if (SubType == XINPUT_DEVSUBTYPE_UNKNOWN)
	return;

	while (pNewJoystick) {
	if (pNewJoystick->bXInputDevice && (pNewJoystick->XInputUserId == userid) && (pNewJoystick->SubType == SubType)) {
	/* if we are replacing the front of the list then update it */
	if (pNewJoystick == *pContext) {
	*pContext = pNewJoystick->pNext;
	} else if (pPrevJoystick) {
	pPrevJoystick->pNext = pNewJoystick->pNext;
	}

	pNewJoystick->pNext = SYS_Joystick;
	SYS_Joystick = pNewJoystick;
	return; /* already in the list. */
	}

	pPrevJoystick = pNewJoystick;
	pNewJoystick = pNewJoystick->pNext;
	}

	pNewJoystick = (JoyStick_DeviceData *)SDL_malloc(sizeof(JoyStick_DeviceData));
	if (!pNewJoystick) {
	return; /* better luck next time? */
	}
	SDL_zerop(pNewJoystick);

	pNewJoystick->joystickname = GetXInputName(userid, SubType);
	if (!pNewJoystick->joystickname) {
	SDL_free(pNewJoystick);
	return; /* better luck next time? */
	}

	pNewJoystick->bXInputDevice = SDL_TRUE;
	if (SDL_XInputUseOldJoystickMapping()) {
	SDL_zero(pNewJoystick->guid);
	} else {
	pNewJoystick->guid.data[0] = 'x';
	pNewJoystick->guid.data[1] = 'i';
	pNewJoystick->guid.data[2] = 'n';
	pNewJoystick->guid.data[3] = 'p';
	pNewJoystick->guid.data[4] = 'u';
	pNewJoystick->guid.data[5] = 't';
	pNewJoystick->guid.data[6] = SubType;
	}
	pNewJoystick->SubType = SubType;
	pNewJoystick->XInputUserId = userid;
	SDL_SYS_AddJoystickDevice(pNewJoystick);
	}

	void
	SDL_XINPUT_JoystickDetect(JoyStick_DeviceData **pContext)
	{
	int iuserid;

	if (!s_bXInputEnabled) {
	return;
	}

	/* iterate in reverse, so these are in the final list in ascending numeric order. */
	for (iuserid = XUSER_MAX_COUNT - 1; iuserid >= 0; iuserid--) {
	const Uint8 userid = (Uint8)iuserid;
	XINPUT_CAPABILITIES capabilities;
	if (XINPUTGETCAPABILITIES(userid, XINPUT_FLAG_GAMEPAD, &capabilities) == ERROR_SUCCESS) {
	AddXInputDevice(userid, capabilities.SubType, pContext);
	}
	}
	}

	int
	SDL_XINPUT_JoystickOpen(SDL_Joystick * joystick, JoyStick_DeviceData *joystickdevice)
	{
	const Uint8 userId = joystickdevice->XInputUserId;
	XINPUT_CAPABILITIES capabilities;
	XINPUT_VIBRATION state;

	SDL_assert(s_bXInputEnabled);
	SDL_assert(XINPUTGETCAPABILITIES);
	SDL_assert(XINPUTSETSTATE);
	SDL_assert(userId < XUSER_MAX_COUNT);

	joystick->hwdata->bXInputDevice = SDL_TRUE;

	if (XINPUTGETCAPABILITIES(userId, XINPUT_FLAG_GAMEPAD, &capabilities) != ERROR_SUCCESS) {
	SDL_free(joystick->hwdata);
	joystick->hwdata = NULL;
	return SDL_SetError("Failed to obtain XInput device capabilities. Device disconnected?");
	}
	SDL_zero(state);
	joystick->hwdata->bXInputHaptic = (XINPUTSETSTATE(userId, &state) == ERROR_SUCCESS);
	joystick->hwdata->userid = userId;

	/* The XInput API has a hard coded button/axis mapping, so we just match it */
	if (SDL_XInputUseOldJoystickMapping()) {
	joystick->naxes = 6;
	joystick->nbuttons = 15;
	} else {
	joystick->naxes = 6;
	joystick->nbuttons = 11;
	joystick->nhats = 1;
	}
	return 0;
	}

	static void
	UpdateXInputJoystickBatteryInformation(SDL_Joystick * joystick, XINPUT_BATTERY_INFORMATION_EX *pBatteryInformation)
	{
	if ( pBatteryInformation->BatteryType != BATTERY_TYPE_UNKNOWN )
	{
	SDL_JoystickPowerLevel ePowerLevel = SDL_JOYSTICK_POWER_UNKNOWN;
	if (pBatteryInformation->BatteryType == BATTERY_TYPE_WIRED) {
	ePowerLevel = SDL_JOYSTICK_POWER_WIRED;
	} else {
	switch ( pBatteryInformation->BatteryLevel )
	{
	case BATTERY_LEVEL_EMPTY:
	ePowerLevel = SDL_JOYSTICK_POWER_EMPTY;
	break;
	case BATTERY_LEVEL_LOW:
	ePowerLevel = SDL_JOYSTICK_POWER_LOW;
	break;
	case BATTERY_LEVEL_MEDIUM:
	ePowerLevel = SDL_JOYSTICK_POWER_MEDIUM;
	break;
	default:
	case BATTERY_LEVEL_FULL:
	ePowerLevel = SDL_JOYSTICK_POWER_FULL;
	break;
	}
	}

	SDL_PrivateJoystickBatteryLevel( joystick, ePowerLevel );
	}
	}

	static void
	UpdateXInputJoystickState_OLD(SDL_Joystick * joystick, XINPUT_STATE_EX pXInputState, XINPUT_BATTERY_INFORMATION_EX pBatteryInformation)
	{
	static WORD s_XInputButtons[] = {
	XINPUT_GAMEPAD_DPAD_UP, XINPUT_GAMEPAD_DPAD_DOWN, XINPUT_GAMEPAD_DPAD_LEFT, XINPUT_GAMEPAD_DPAD_RIGHT,
	XINPUT_GAMEPAD_START, XINPUT_GAMEPAD_BACK, XINPUT_GAMEPAD_LEFT_THUMB, XINPUT_GAMEPAD_RIGHT_THUMB,
	XINPUT_GAMEPAD_LEFT_SHOULDER, XINPUT_GAMEPAD_RIGHT_SHOULDER,
	XINPUT_GAMEPAD_A, XINPUT_GAMEPAD_B, XINPUT_GAMEPAD_X, XINPUT_GAMEPAD_Y,
	XINPUT_GAMEPAD_GUIDE
	};
	WORD wButtons = pXInputState->Gamepad.wButtons;
	Uint8 button;

	SDL_PrivateJoystickAxis(joystick, 0, (Sint16)pXInputState->Gamepad.sThumbLX);
	SDL_PrivateJoystickAxis(joystick, 1, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbLY)));
	SDL_PrivateJoystickAxis(joystick, 2, (Sint16)pXInputState->Gamepad.sThumbRX);
	SDL_PrivateJoystickAxis(joystick, 3, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbRY)));
	SDL_PrivateJoystickAxis(joystick, 4, (Sint16)(((int)pXInputState->Gamepad.bLeftTrigger * 65535 / 255) - 32768));
	SDL_PrivateJoystickAxis(joystick, 5, (Sint16)(((int)pXInputState->Gamepad.bRightTrigger * 65535 / 255) - 32768));

	for (button = 0; button < SDL_arraysize(s_XInputButtons); ++button) {
	SDL_PrivateJoystickButton(joystick, button, (wButtons & s_XInputButtons[button]) ? SDL_PRESSED : SDL_RELEASED);
	}

	UpdateXInputJoystickBatteryInformation( joystick, pBatteryInformation );
	}

	static void
	UpdateXInputJoystickState(SDL_Joystick * joystick, XINPUT_STATE_EX pXInputState, XINPUT_BATTERY_INFORMATION_EX pBatteryInformation)
	{
	static WORD s_XInputButtons[] = {
	XINPUT_GAMEPAD_A, XINPUT_GAMEPAD_B, XINPUT_GAMEPAD_X, XINPUT_GAMEPAD_Y,
	XINPUT_GAMEPAD_LEFT_SHOULDER, XINPUT_GAMEPAD_RIGHT_SHOULDER, XINPUT_GAMEPAD_BACK, XINPUT_GAMEPAD_START,
	XINPUT_GAMEPAD_LEFT_THUMB, XINPUT_GAMEPAD_RIGHT_THUMB,
	XINPUT_GAMEPAD_GUIDE
	};
	WORD wButtons = pXInputState->Gamepad.wButtons;
	Uint8 button;
	Uint8 hat = SDL_HAT_CENTERED;

	SDL_PrivateJoystickAxis(joystick, 0, (Sint16)pXInputState->Gamepad.sThumbLX);
	SDL_PrivateJoystickAxis(joystick, 1, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbLY)));
	SDL_PrivateJoystickAxis(joystick, 2, (Sint16)(((int)pXInputState->Gamepad.bLeftTrigger * 65535 / 255) - 32768));
	SDL_PrivateJoystickAxis(joystick, 3, (Sint16)pXInputState->Gamepad.sThumbRX);
	SDL_PrivateJoystickAxis(joystick, 4, (Sint16)(-SDL_max(-32767, pXInputState->Gamepad.sThumbRY)));
	SDL_PrivateJoystickAxis(joystick, 5, (Sint16)(((int)pXInputState->Gamepad.bRightTrigger * 65535 / 255) - 32768));

	for (button = 0; button < SDL_arraysize(s_XInputButtons); ++button) {
	SDL_PrivateJoystickButton(joystick, button, (wButtons & s_XInputButtons[button]) ? SDL_PRESSED : SDL_RELEASED);
	}

	if (wButtons & XINPUT_GAMEPAD_DPAD_UP) {
	hat \|= SDL_HAT_UP;
	}
	if (wButtons & XINPUT_GAMEPAD_DPAD_DOWN) {
	hat \|= SDL_HAT_DOWN;
	}
	if (wButtons & XINPUT_GAMEPAD_DPAD_LEFT) {
	hat \|= SDL_HAT_LEFT;
	}
	if (wButtons & XINPUT_GAMEPAD_DPAD_RIGHT) {
	hat \|= SDL_HAT_RIGHT;
	}
	SDL_PrivateJoystickHat(joystick, 0, hat);

	UpdateXInputJoystickBatteryInformation( joystick, pBatteryInformation );
	}

	void
	SDL_XINPUT_JoystickUpdate(SDL_Joystick * joystick)
	{
	HRESULT result;
	XINPUT_STATE_EX XInputState;
	XINPUT_BATTERY_INFORMATION_EX XBatteryInformation;

	if (!XINPUTGETSTATE)
	return;

	result = XINPUTGETSTATE(joystick->hwdata->userid, &XInputState);
	if (result == ERROR_DEVICE_NOT_CONNECTED) {
	joystick->hwdata->send_remove_event = SDL_TRUE;
	joystick->hwdata->removed = SDL_TRUE;
	return;
	}

	SDL_zero( XBatteryInformation );
	if ( XINPUTGETBATTERYINFORMATION )
	{
	result = XINPUTGETBATTERYINFORMATION( joystick->hwdata->userid, BATTERY_DEVTYPE_GAMEPAD, &XBatteryInformation );
	}

	/* only fire events if the data changed from last time */
	if (XInputState.dwPacketNumber && XInputState.dwPacketNumber != joystick->hwdata->dwPacketNumber) {
	if (SDL_XInputUseOldJoystickMapping()) {
	UpdateXInputJoystickState_OLD(joystick, &XInputState, &XBatteryInformation);
	} else {
	UpdateXInputJoystickState(joystick, &XInputState, &XBatteryInformation);
	}
	joystick->hwdata->dwPacketNumber = XInputState.dwPacketNumber;
	}
	}

	void
	SDL_XINPUT_JoystickClose(SDL_Joystick * joystick)
	{
	}

	void
	SDL_XINPUT_JoystickQuit(void)
	{
	if (s_bXInputEnabled) {
	WIN_UnloadXInputDLL();
	}
	}

	SDL_bool
	SDL_SYS_IsXInputGamepad_DeviceIndex(int device_index)
	{
	JoyStick_DeviceData *device = SYS_Joystick;
	int index;

	for (index = device_index; index > 0; index--)
	device = device->pNext;

	return device->bXInputDevice;
	}

	#else /* !SDL_JOYSTICK_XINPUT */

	typedef struct JoyStick_DeviceData JoyStick_DeviceData;

	SDL_bool SDL_XINPUT_Enabled(void)
	{
	return SDL_FALSE;
	}

	int
	SDL_XINPUT_JoystickInit(void)
	{
	return 0;
	}

	void
	SDL_XINPUT_JoystickDetect(JoyStick_DeviceData **pContext)
	{
	}

	int
	SDL_XINPUT_JoystickOpen(SDL_Joystick * joystick, JoyStick_DeviceData *joystickdevice)
	{
	return SDL_Unsupported();
	}

	void
	SDL_XINPUT_JoystickUpdate(SDL_Joystick * joystick)
	{
	}

	void
	SDL_XINPUT_JoystickClose(SDL_Joystick * joystick)
	{
	}

	void
	SDL_XINPUT_JoystickQuit(void)
	{
	}

	#endif /* SDL_JOYSTICK_XINPUT */

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