1 /*

     2  * Name        : Accelerometer.cpp

     3  * Description : Accelerometer helper class

     4  * Project     : This file is part of OpenMAR, an Open Mobile Augmented Reality browser

     5  * Website     : http://OpenMAR.org

     6  *

     7  * Copyright (c) 2010 David Caabeiro

     8  *

     9  * All rights reserved. This program and the accompanying materials are made available 

    10  * under the terms of the Eclipse Public License v1.0 which accompanies this 

    11  * distribution, and is available at http://www.eclipse.org/legal/epl-v10.html

    12  *

    13  */

    14 

    15 #include "Accelerometer.h"

    16 

    17 #include <SensrvAccelerometerSensor.h>

    18 

    19 #include <SensrvChannel.h>

    20 #include <SensrvChannelFinder.h>

    21 #include <SensrvChannelInfo.h>

    22 

    23 CAccelerometer* CAccelerometer::NewL()

    24 {

    25     CAccelerometer* self = new(ELeave) CAccelerometer;

    26     CleanupStack::PushL(self);

    27     self->ConstructL();

    28     CleanupStack::Pop(self);

    29 

    30     return self;

    31 }

    32 

    33 CAccelerometer::~CAccelerometer()

    34 {

    35     iSensorChannel->CloseChannel();

    36 }

    37 

    38 CAccelerometer::CAccelerometer()

    39 {}

    40 

    41 void CAccelerometer::ConstructL()

    42 {

    43     CSensrvChannelFinder* sensorChannelFinder = CSensrvChannelFinder::NewLC();

    44 

    45     RSensrvChannelInfoList channelInfoList;

    46     CleanupClosePushL(channelInfoList);

    47 

    48     TSensrvChannelInfo mySearchConditions;

    49     mySearchConditions.iChannelType = KSensrvChannelTypeIdAccelerometerXYZAxisData;

    50 

    51     sensorChannelFinder->FindChannelsL(channelInfoList, mySearchConditions);

    52 

    53     TSensrvChannelInfo channelInfo;

    54 

    55     if (channelInfoList.Count() > 0)

    56         channelInfo = channelInfoList[0];

    57     else

    58         User::Leave(KErrNotFound);

    59 

    60     CleanupStack::PopAndDestroy(&channelInfoList);

    61     CleanupStack::PopAndDestroy(sensorChannelFinder);

    62 

    63     iSensorChannel = CSensrvChannel::NewL(channelInfo);

    64     iSensorChannel->OpenChannelL();

    65 }

    66 

    67 void CAccelerometer::StartL()

    68 {

    69     iSensorChannel->StartDataListeningL(this, 1, 8, 0);

    70 }

    71 

    72 void CAccelerometer::Stop()

    73 {

    74     iSensorChannel->StopDataListening();

    75 }

    76 

    77 void CAccelerometer::DataReceived(CSensrvChannel& aChannel, TInt aCount, TInt aDataLost)

    78 {

    79     if (aChannel.GetChannelInfo().iChannelType ==  KSensrvChannelTypeIdAccelerometerXYZAxisData)

    80     {

    81         TPckgBuf<TSensrvAccelerometerAxisData> dataBuffer;

    82         TSensrvAccelerometerAxisData data;

    83 

    84         for (TInt i = 0; i < aCount; ++i)

    85         {

    86             aChannel.GetData(dataBuffer);

    87 

    88             data = dataBuffer();

    89             // Do something with the date in data variable

    90             // data.iTimeStamp

    91 

    92             // Compensate axis for landscape mode

    93             TInt x = -data.iAxisY;

    94             TInt y =  data.iAxisX;

    95             TInt z =  data.iAxisZ;

    96 #if 0

    97             TInt x = data.iAxisX;

    98             TInt y = data.iAxisY;

    99             TInt z = data.iAxisZ;

   100 #endif

   101             const TReal K128 = 0.0078125;   // 1/128

   102             const TReal KPole1 = 0.97;      // Pole of lowpass filter applied to X and Y

   103             const TReal KPole2 = 0.90;      // Pole of lowpass filter applied to Z

   104             const TReal KPole3 = 0.75;      // Pole of highpass filter applied to Z

   105 

   106             // Single-pole lowpass-filtering of X and Y

   107             iX1 = KPole1 * iX1 + ( 1.0 - KPole1 ) * ( K128 * x );

   108             iY1 = KPole1 * iY1 + ( 1.0 - KPole1 ) * ( K128 * y );

   109 

   110             // Single-pole lowpass-filtering of Z

   111             iZ0 = KPole2 * iZ1 + ( 1.0 - KPole2 ) * ( K128 * z );

   112             // 1st order highpass-filtering of Z (zero at 1)

   113             iZ2 = KPole3 * iZ2 + ( 1.0 - KPole3 ) * ( iZ0 - iZ1 );

   114 

   115             // Update variables for use at next sample

   116             iZ1 = iZ0;

   117         }

   118     }

   119 }

   120 

   121 void CAccelerometer::DataError(CSensrvChannel& aChannel, TSensrvErrorSeverity aError)

   122 {

   123 }

   124 

   125 void CAccelerometer::GetDataListenerInterfaceL(TUid aInterfaceUid, TAny*& aInterface)

   126 {}