- /* 
-   Simple DirectMedia Layer 
-   Copyright (C) 1997-2018 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. 
- */ 
-   
- /** 
-  *  \file SDL_sensor.h 
-  * 
-  *  Include file for SDL sensor event handling 
-  * 
-  */ 
-   
- #ifndef _SDL_sensor_h 
- #define _SDL_sensor_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 
- /* *INDENT-OFF* */ 
- extern "C" { 
- /* *INDENT-ON* */ 
- #endif 
-   
- /** 
-  *  \brief SDL_sensor.h 
-  * 
-  *  In order to use these functions, SDL_Init() must have been called 
-  *  with the ::SDL_INIT_SENSOR flag.  This causes SDL to scan the system 
-  *  for sensors, and load appropriate drivers. 
-  */ 
-   
- struct _SDL_Sensor; 
- typedef struct _SDL_Sensor SDL_Sensor; 
-   
- /** 
-  * This is a unique ID for a sensor for the time it is connected to the system, 
-  * and is never reused for the lifetime of the application. 
-  * 
-  * The ID value starts at 0 and increments from there. The value -1 is an invalid ID. 
-  */ 
- typedef Sint32 SDL_SensorID; 
-   
- /* The different sensors defined by SDL 
-  * 
-  * Additional sensors may be available, using platform dependent semantics. 
-  * 
-  * Hare are the additional Android sensors: 
-  * https://developer.android.com/reference/android/hardware/SensorEvent.html#values 
-  */ 
- typedef enum 
- { 
-     SDL_SENSOR_INVALID = -1,    /**< Returned for an invalid sensor */ 
-     SDL_SENSOR_UNKNOWN,         /**< Unknown sensor type */ 
-     SDL_SENSOR_ACCEL,           /**< Accelerometer */ 
-     SDL_SENSOR_GYRO             /**< Gyroscope */ 
- } SDL_SensorType; 
-   
- /** 
-  * Accelerometer sensor 
-  * 
-  * The accelerometer returns the current acceleration in SI meters per 
-  * second squared. This includes gravity, so a device at rest will have 
-  * an acceleration of SDL_STANDARD_GRAVITY straight down. 
-  * 
-  * values[0]: Acceleration on the x axis 
-  * values[1]: Acceleration on the y axis 
-  * values[2]: Acceleration on the z axis 
-  * 
-  * For phones held in portrait mode, the axes are defined as follows: 
-  * -X ... +X : left ... right 
-  * -Y ... +Y : bottom ... top 
-  * -Z ... +Z : farther ... closer 
-  *  
-  * The axis data is not changed when the phone is rotated. 
-  * 
-  * \sa SDL_GetDisplayOrientation() 
-  */ 
- #define SDL_STANDARD_GRAVITY    9.80665f 
-   
- /** 
-  * Gyroscope sensor 
-  * 
-  * The gyroscope returns the current rate of rotation in radians per second. 
-  * The rotation is positive in the counter-clockwise direction. That is, 
-  * an observer looking from a positive location on one of the axes would 
-  * see positive rotation on that axis when it appeared to be rotating 
-  * counter-clockwise. 
-  * 
-  * values[0]: Angular speed around the x axis 
-  * values[1]: Angular speed around the y axis 
-  * values[2]: Angular speed around the z axis 
-  * 
-  * For phones held in portrait mode, the axes are defined as follows: 
-  * -X ... +X : left ... right 
-  * -Y ... +Y : bottom ... top 
-  * -Z ... +Z : farther ... closer 
-  *  
-  * The axis data is not changed when the phone is rotated. 
-  * 
-  * \sa SDL_GetDisplayOrientation() 
-  */ 
-   
- /* Function prototypes */ 
-   
- /** 
-  *  \brief Count the number of sensors attached to the system right now 
-  */ 
- extern DECLSPEC int SDLCALL SDL_NumSensors(void); 
-   
- /** 
-  *  \brief Get the implementation dependent name of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  *  
-  *  \return The sensor name, or NULL if device_index is out of range. 
-  */ 
- extern DECLSPEC const char *SDLCALL SDL_SensorGetDeviceName(int device_index); 
-   
- /** 
-  *  \brief Get the type of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor type, or SDL_SENSOR_INVALID if device_index is out of range. 
-  */ 
- extern DECLSPEC SDL_SensorType SDLCALL SDL_SensorGetDeviceType(int device_index); 
-   
- /** 
-  *  \brief Get the platform dependent type of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor platform dependent type, or -1 if device_index is out of range. 
-  */ 
- extern DECLSPEC int SDLCALL SDL_SensorGetDeviceNonPortableType(int device_index); 
-   
- /** 
-  *  \brief Get the instance ID of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor instance ID, or -1 if device_index is out of range. 
-  */ 
- extern DECLSPEC SDL_SensorID SDLCALL SDL_SensorGetDeviceInstanceID(int device_index); 
-   
- /** 
-  *  \brief Open a sensor for use. 
-  * 
-  *  The index passed as an argument refers to the N'th sensor on the system. 
-  * 
-  *  \return A sensor identifier, or NULL if an error occurred. 
-  */ 
- extern DECLSPEC SDL_Sensor *SDLCALL SDL_SensorOpen(int device_index); 
-   
- /** 
-  * Return the SDL_Sensor associated with an instance id. 
-  */ 
- extern DECLSPEC SDL_Sensor *SDLCALL SDL_SensorFromInstanceID(SDL_SensorID instance_id); 
-   
- /** 
-  *  \brief Get the implementation dependent name of a sensor. 
-  * 
-  *  \return The sensor name, or NULL if the sensor is NULL. 
-  */ 
- extern DECLSPEC const char *SDLCALL SDL_SensorGetName(SDL_Sensor *sensor); 
-   
- /** 
-  *  \brief Get the type of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor type, or SDL_SENSOR_INVALID if the sensor is NULL. 
-  */ 
- extern DECLSPEC SDL_SensorType SDLCALL SDL_SensorGetType(SDL_Sensor *sensor); 
-   
- /** 
-  *  \brief Get the platform dependent type of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor platform dependent type, or -1 if the sensor is NULL. 
-  */ 
- extern DECLSPEC int SDLCALL SDL_SensorGetNonPortableType(SDL_Sensor *sensor); 
-   
- /** 
-  *  \brief Get the instance ID of a sensor. 
-  * 
-  *  This can be called before any sensors are opened. 
-  * 
-  *  \return The sensor instance ID, or -1 if the sensor is NULL. 
-  */ 
- extern DECLSPEC SDL_SensorID SDLCALL SDL_SensorGetInstanceID(SDL_Sensor *sensor); 
-   
- /** 
-  *  Get the current state of an opened sensor. 
-  * 
-  *  The number of values and interpretation of the data is sensor dependent. 
-  * 
-  *  \param sensor The sensor to query 
-  *  \param data A pointer filled with the current sensor state 
-  *  \param num_values The number of values to write to data 
-  * 
-  *  \return 0 or -1 if an error occurred. 
-  */ 
- extern DECLSPEC int SDLCALL SDL_SensorGetData(SDL_Sensor * sensor, float *data, int num_values); 
-   
- /** 
-  *  Close a sensor previously opened with SDL_SensorOpen() 
-  */ 
- extern DECLSPEC void SDLCALL SDL_SensorClose(SDL_Sensor * sensor); 
-   
- /** 
-  *  Update the current state of the open sensors. 
-  * 
-  *  This is called automatically by the event loop if sensor events are enabled. 
-  * 
-  *  This needs to be called from the thread that initialized the sensor subsystem. 
-  */ 
- extern DECLSPEC void SDLCALL SDL_SensorUpdate(void); 
-   
-   
- /* Ends C function definitions when using C++ */ 
- #ifdef __cplusplus 
- /* *INDENT-OFF* */ 
- } 
- /* *INDENT-ON* */ 
- #endif 
- #include "close_code.h" 
-   
- #endif /* _SDL_sensor_h */ 
-   
- /* vi: set ts=4 sw=4 expandtab: */ 
-