/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_SENSOR_H
#define ANDROID_SENSOR_H
/******************************************************************
*
* IMPORTANT NOTICE:
*
* This file is part of Android's set of stable system headers
* exposed by the Android NDK (Native Development Kit).
*
* Third-party source AND binary code relies on the definitions
* here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES.
*
* - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES)
* - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS
* - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY
* - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES
*/
/*
* Structures and functions to receive and process sensor events in
* native code.
*
*/
#include <sys/types.h>
#include <android/looper.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Sensor types
* (keep in sync with hardware/sensor.h)
*/
enum {
ASENSOR_TYPE_ACCELEROMETER = 1,
ASENSOR_TYPE_MAGNETIC_FIELD = 2,
ASENSOR_TYPE_GYROSCOPE = 4,
ASENSOR_TYPE_LIGHT = 5,
ASENSOR_TYPE_PROXIMITY = 8
};
/*
* Sensor accuracy measure
*/
enum {
ASENSOR_STATUS_UNRELIABLE = 0,
ASENSOR_STATUS_ACCURACY_LOW = 1,
ASENSOR_STATUS_ACCURACY_MEDIUM = 2,
ASENSOR_STATUS_ACCURACY_HIGH = 3
};
/*
* A few useful constants
*/
/* Earth's gravity in m/s^2 */
#define ASENSOR_STANDARD_GRAVITY (9.80665f)
/* Maximum magnetic field on Earth's surface in uT */
#define ASENSOR_MAGNETIC_FIELD_EARTH_MAX (60.0f)
/* Minimum magnetic field on Earth's surface in uT*/
#define ASENSOR_MAGNETIC_FIELD_EARTH_MIN (30.0f)
/*
* A sensor event.
*/
/* NOTE: Must match hardware/sensors.h */
typedef struct ASensorVector {
union {
float v[3];
struct {
float x;
float y;
float z;
};
struct {
float azimuth;
float pitch;
float roll;
};
};
int8_t status;
uint8_t reserved[3];
} ASensorVector;
/* NOTE: Must match hardware/sensors.h */
typedef struct ASensorEvent {
int32_t version; /* sizeof(struct ASensorEvent) */
int32_t sensor;
int32_t type;
int32_t reserved0;
int64_t timestamp;
union {
float data[16];
ASensorVector vector;
ASensorVector acceleration;
ASensorVector magnetic;
float temperature;
float distance;
float light;
float pressure;
};
int32_t reserved1[4];
} ASensorEvent;
struct ASensorManager;
typedef struct ASensorManager ASensorManager;
struct ASensorEventQueue;
typedef struct ASensorEventQueue ASensorEventQueue;
struct ASensor;
typedef struct ASensor ASensor;
typedef ASensor const* ASensorRef;
typedef ASensorRef const* ASensorList;
/*****************************************************************************/
/*
* Get a reference to the sensor manager. ASensorManager is a singleton.
*
* Example:
*
* ASensorManager* sensorManager = ASensorManager_getInstance();
*
*/
ASensorManager* ASensorManager_getInstance();
/*
* Returns the list of available sensors.
*/
int ASensorManager_getSensorList(ASensorManager* manager, ASensorList* list);
/*
* Returns the default sensor for the given type, or NULL if no sensor
* of that type exist.
*/
ASensor const* ASensorManager_getDefaultSensor(ASensorManager* manager, int type);
/*
* Creates a new sensor event queue and associate it with a looper.
*/
ASensorEventQueue* ASensorManager_createEventQueue(ASensorManager* manager,
ALooper* looper, int ident, ALooper_callbackFunc callback, void* data);
/*
* Destroys the event queue and free all resources associated to it.
*/
int ASensorManager_destroyEventQueue(ASensorManager* manager, ASensorEventQueue* queue);
/*****************************************************************************/
/*
* Enable the selected sensor. Returns a negative error code on failure.
*/
int ASensorEventQueue_enableSensor(ASensorEventQueue* queue, ASensor const* sensor);
/*
* Disable the selected sensor. Returns a negative error code on failure.
*/
int ASensorEventQueue_disableSensor(ASensorEventQueue* queue, ASensor const* sensor);
/*
* Sets the delivery rate of events in microseconds for the given sensor.
* Note that this is a hint only, generally event will arrive at a higher
* rate. It is an error to set a rate inferior to the value returned by
* ASensor_getMinDelay().
* Returns a negative error code on failure.
*/
int ASensorEventQueue_setEventRate(ASensorEventQueue* queue, ASensor const* sensor, int32_t usec);
/*
* Returns true if there are one or more events available in the
* sensor queue. Returns 1 if the queue has events; 0 if
* it does not have events; and a negative value if there is an error.
*/
int ASensorEventQueue_hasEvents(ASensorEventQueue* queue);
/*
* Returns the next available events from the queue. Returns a negative
* value if no events are available or an error has occurred, otherwise
* the number of events returned.
*
* Examples:
* ASensorEvent event;
* ssize_t numEvent = ASensorEventQueue_getEvents(queue, &event, 1);
*
* ASensorEvent eventBuffer[8];
* ssize_t numEvent = ASensorEventQueue_getEvents(queue, eventBuffer, 8);
*
*/
ssize_t ASensorEventQueue_getEvents(ASensorEventQueue* queue,
ASensorEvent* events, size_t count);
/*****************************************************************************/
/*
* Returns this sensor's name (non localized)
*/
const char* ASensor_getName(ASensor const* sensor);
/*
* Returns this sensor's vendor's name (non localized)
*/
const char* ASensor_getVendor(ASensor const* sensor);
/*
* Return this sensor's type
*/
int ASensor_getType(ASensor const* sensor);
/*
* Returns this sensors's resolution
*/
float ASensor_getResolution(ASensor const* sensor);
/*
* Returns the minimum delay allowed between events in microseconds.
* A value of zero means that this sensor doesn't report events at a
* constant rate, but rather only when a new data is available.
*/
int ASensor_getMinDelay(ASensor const* sensor);
#ifdef __cplusplus
};
#endif
#endif // ANDROID_SENSOR_H