1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2024 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_sensor.h
24 *
25 * Include file for SDL sensor event handling
26 *
27 */
28
29#ifndef SDL_sensor_h_
30#define SDL_sensor_h_
31
32#include "SDL_stdinc.h"
33#include "SDL_error.h"
34
35#include "begin_code.h"
36/* Set up for C function definitions, even when using C++ */
37#ifdef __cplusplus
38/* *INDENT-OFF* */
39extern "C" {
40/* *INDENT-ON* */
41#endif
42
43/**
44 * \brief SDL_sensor.h
45 *
46 * In order to use these functions, SDL_Init() must have been called
47 * with the ::SDL_INIT_SENSOR flag. This causes SDL to scan the system
48 * for sensors, and load appropriate drivers.
49 */
50
51struct _SDL_Sensor;
52typedef struct _SDL_Sensor SDL_Sensor;
53
54/**
55 * This is a unique ID for a sensor for the time it is connected to the system,
56 * and is never reused for the lifetime of the application.
57 *
58 * The ID value starts at 0 and increments from there. The value -1 is an invalid ID.
59 */
60typedef Sint32 SDL_SensorID;
61
62/* The different sensors defined by SDL
63 *
64 * Additional sensors may be available, using platform dependent semantics.
65 *
66 * Hare are the additional Android sensors:
67 * https://developer.android.com/reference/android/hardware/SensorEvent.html#values
68 */
69typedef enum
70{
71 SDL_SENSOR_INVALID = -1, /**< Returned for an invalid sensor */
72 SDL_SENSOR_UNKNOWN, /**< Unknown sensor type */
73 SDL_SENSOR_ACCEL, /**< Accelerometer */
74 SDL_SENSOR_GYRO, /**< Gyroscope */
75 SDL_SENSOR_ACCEL_L, /**< Accelerometer for left Joy-Con controller and Wii nunchuk */
76 SDL_SENSOR_GYRO_L, /**< Gyroscope for left Joy-Con controller */
77 SDL_SENSOR_ACCEL_R, /**< Accelerometer for right Joy-Con controller */
78 SDL_SENSOR_GYRO_R /**< Gyroscope for right Joy-Con controller */
79} SDL_SensorType;
80
81/**
82 * Accelerometer sensor
83 *
84 * The accelerometer returns the current acceleration in SI meters per
85 * second squared. This measurement includes the force of gravity, so
86 * a device at rest will have an value of SDL_STANDARD_GRAVITY away
87 * from the center of the earth, which is a positive Y value.
88 *
89 * values[0]: Acceleration on the x axis
90 * values[1]: Acceleration on the y axis
91 * values[2]: Acceleration on the z axis
92 *
93 * For phones held in portrait mode and game controllers held in front of you,
94 * the axes are defined as follows:
95 * -X ... +X : left ... right
96 * -Y ... +Y : bottom ... top
97 * -Z ... +Z : farther ... closer
98 *
99 * The axis data is not changed when the phone is rotated.
100 *
101 * \sa SDL_GetDisplayOrientation()
102 */
103#define SDL_STANDARD_GRAVITY 9.80665f
104
105/**
106 * Gyroscope sensor
107 *
108 * The gyroscope returns the current rate of rotation in radians per second.
109 * The rotation is positive in the counter-clockwise direction. That is,
110 * an observer looking from a positive location on one of the axes would
111 * see positive rotation on that axis when it appeared to be rotating
112 * counter-clockwise.
113 *
114 * values[0]: Angular speed around the x axis (pitch)
115 * values[1]: Angular speed around the y axis (yaw)
116 * values[2]: Angular speed around the z axis (roll)
117 *
118 * For phones held in portrait mode and game controllers held in front of you,
119 * the axes are defined as follows:
120 * -X ... +X : left ... right
121 * -Y ... +Y : bottom ... top
122 * -Z ... +Z : farther ... closer
123 *
124 * The axis data is not changed when the phone or controller is rotated.
125 *
126 * \sa SDL_GetDisplayOrientation()
127 */
128
129/* Function prototypes */
130
131/**
132 * Locking for multi-threaded access to the sensor API
133 *
134 * If you are using the sensor API or handling events from multiple threads
135 * you should use these locking functions to protect access to the sensors.
136 *
137 * In particular, you are guaranteed that the sensor list won't change, so the
138 * API functions that take a sensor index will be valid, and sensor events
139 * will not be delivered.
140 *
141 * \since This function is available since SDL 2.0.14.
142 */
143extern DECLSPEC void SDLCALL SDL_LockSensors(void);
144extern DECLSPEC void SDLCALL SDL_UnlockSensors(void);
145
146/**
147 * Count the number of sensors attached to the system right now.
148 *
149 * \returns the number of sensors detected.
150 *
151 * \since This function is available since SDL 2.0.9.
152 */
153extern DECLSPEC int SDLCALL SDL_NumSensors(void);
154
155/**
156 * Get the implementation dependent name of a sensor.
157 *
158 * \param device_index The sensor to obtain name from
159 * \returns the sensor name, or NULL if `device_index` is out of range.
160 *
161 * \since This function is available since SDL 2.0.9.
162 */
163extern DECLSPEC const char *SDLCALL SDL_SensorGetDeviceName(int device_index);
164
165/**
166 * Get the type of a sensor.
167 *
168 * \param device_index The sensor to get the type from
169 * \returns the SDL_SensorType, or `SDL_SENSOR_INVALID` if `device_index` is
170 * out of range.
171 *
172 * \since This function is available since SDL 2.0.9.
173 */
174extern DECLSPEC SDL_SensorType SDLCALL SDL_SensorGetDeviceType(int device_index);
175
176/**
177 * Get the platform dependent type of a sensor.
178 *
179 * \param device_index The sensor to check
180 * \returns the sensor platform dependent type, or -1 if `device_index` is out
181 * of range.
182 *
183 * \since This function is available since SDL 2.0.9.
184 */
185extern DECLSPEC int SDLCALL SDL_SensorGetDeviceNonPortableType(int device_index);
186
187/**
188 * Get the instance ID of a sensor.
189 *
190 * \param device_index The sensor to get instance id from
191 * \returns the sensor instance ID, or -1 if `device_index` is out of range.
192 *
193 * \since This function is available since SDL 2.0.9.
194 */
195extern DECLSPEC SDL_SensorID SDLCALL SDL_SensorGetDeviceInstanceID(int device_index);
196
197/**
198 * Open a sensor for use.
199 *
200 * \param device_index The sensor to open
201 * \returns an SDL_Sensor sensor object, or NULL if an error occurred.
202 *
203 * \since This function is available since SDL 2.0.9.
204 */
205extern DECLSPEC SDL_Sensor *SDLCALL SDL_SensorOpen(int device_index);
206
207/**
208 * Return the SDL_Sensor associated with an instance id.
209 *
210 * \param instance_id The sensor from instance id
211 * \returns an SDL_Sensor object.
212 *
213 * \since This function is available since SDL 2.0.9.
214 */
215extern DECLSPEC SDL_Sensor *SDLCALL SDL_SensorFromInstanceID(SDL_SensorID instance_id);
216
217/**
218 * Get the implementation dependent name of a sensor
219 *
220 * \param sensor The SDL_Sensor object
221 * \returns the sensor name, or NULL if `sensor` is NULL.
222 *
223 * \since This function is available since SDL 2.0.9.
224 */
225extern DECLSPEC const char *SDLCALL SDL_SensorGetName(SDL_Sensor *sensor);
226
227/**
228 * Get the type of a sensor.
229 *
230 * \param sensor The SDL_Sensor object to inspect
231 * \returns the SDL_SensorType type, or `SDL_SENSOR_INVALID` if `sensor` is
232 * NULL.
233 *
234 * \since This function is available since SDL 2.0.9.
235 */
236extern DECLSPEC SDL_SensorType SDLCALL SDL_SensorGetType(SDL_Sensor *sensor);
237
238/**
239 * Get the platform dependent type of a sensor.
240 *
241 * \param sensor The SDL_Sensor object to inspect
242 * \returns the sensor platform dependent type, or -1 if `sensor` is NULL.
243 *
244 * \since This function is available since SDL 2.0.9.
245 */
246extern DECLSPEC int SDLCALL SDL_SensorGetNonPortableType(SDL_Sensor *sensor);
247
248/**
249 * Get the instance ID of a sensor.
250 *
251 * \param sensor The SDL_Sensor object to inspect
252 * \returns the sensor instance ID, or -1 if `sensor` is NULL.
253 *
254 * \since This function is available since SDL 2.0.9.
255 */
256extern DECLSPEC SDL_SensorID SDLCALL SDL_SensorGetInstanceID(SDL_Sensor *sensor);
257
258/**
259 * Get the current state of an opened sensor.
260 *
261 * The number of values and interpretation of the data is sensor dependent.
262 *
263 * \param sensor The SDL_Sensor object to query
264 * \param data A pointer filled with the current sensor state
265 * \param num_values The number of values to write to data
266 * \returns 0 or -1 if an error occurred.
267 *
268 * \since This function is available since SDL 2.0.9.
269 */
270extern DECLSPEC int SDLCALL SDL_SensorGetData(SDL_Sensor *sensor, float *data, int num_values);
271
272/**
273 * Get the current state of an opened sensor with the timestamp of the last
274 * update.
275 *
276 * The number of values and interpretation of the data is sensor dependent.
277 *
278 * \param sensor The SDL_Sensor object to query
279 * \param timestamp A pointer filled with the timestamp in microseconds of the
280 * current sensor reading if available, or 0 if not
281 * \param data A pointer filled with the current sensor state
282 * \param num_values The number of values to write to data
283 * \returns 0 or -1 if an error occurred.
284 *
285 * \since This function is available since SDL 2.26.0.
286 */
287extern DECLSPEC int SDLCALL SDL_SensorGetDataWithTimestamp(SDL_Sensor *sensor, Uint64 *timestamp, float *data, int num_values);
288
289/**
290 * Close a sensor previously opened with SDL_SensorOpen().
291 *
292 * \param sensor The SDL_Sensor object to close
293 *
294 * \since This function is available since SDL 2.0.9.
295 */
296extern DECLSPEC void SDLCALL SDL_SensorClose(SDL_Sensor *sensor);
297
298/**
299 * Update the current state of the open sensors.
300 *
301 * This is called automatically by the event loop if sensor events are
302 * enabled.
303 *
304 * This needs to be called from the thread that initialized the sensor
305 * subsystem.
306 *
307 * \since This function is available since SDL 2.0.9.
308 */
309extern DECLSPEC void SDLCALL SDL_SensorUpdate(void);
310
311
312/* Ends C function definitions when using C++ */
313#ifdef __cplusplus
314/* *INDENT-OFF* */
315}
316/* *INDENT-ON* */
317#endif
318#include "close_code.h"
319
320#endif /* SDL_sensor_h_ */
321
322/* vi: set ts=4 sw=4 expandtab: */
323

source code of include/SDL2/SDL_sensor.h