replicant-frameworks_native/services/sensorservice/GravitySensor.h
Mathias Agopian 87c9dbb728 Uses 4-th order low-pass for extracting gravity.
Most accelerometers have 8-bits accuracy so we beed to
reject 48dB in thestop-band, which requires a 4-th order
filter at the cut-off frequency we're using.

Change-Id: Ic00421d38d751641f86b1f3ad7663e6b44a91198
2012-06-27 17:07:54 -07:00

57 lines
1.8 KiB
C++

/*
* 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_GRAVITY_SENSOR_H
#define ANDROID_GRAVITY_SENSOR_H
#include <stdint.h>
#include <sys/types.h>
#include <gui/Sensor.h>
#include "SensorDevice.h"
#include "SensorInterface.h"
#include "SecondOrderLowPassFilter.h"
// ---------------------------------------------------------------------------
namespace android {
// ---------------------------------------------------------------------------
class GravitySensor : public SensorInterface {
SensorDevice& mSensorDevice;
Sensor mAccelerometer;
bool mEnabled;
double mAccTime;
SecondOrderLowPassFilter mLowPass;
CascadedBiquadFilter mX, mY, mZ;
public:
GravitySensor(sensor_t const* list, size_t count);
virtual bool process(sensors_event_t* outEvent,
const sensors_event_t& event);
virtual bool isEnabled() const;
virtual status_t activate(void* ident, bool enabled);
virtual status_t setDelay(void* ident, int handle, int64_t ns);
virtual Sensor getSensor() const;
virtual bool isVirtual() const { return true; }
};
// ---------------------------------------------------------------------------
}; // namespace android
#endif // ANDROID_GRAVITY_SENSOR_H