csensordatafilter.h

一个基于symbian s60 3rd 的3D汽车游戏演示程序,模拟器上编译通过。

   /*
============================================================================
    * Name : CSonsorDataFilter.h
    * Part of : Example3D
    * Description : Definition of CSensorDataFilter
    * Copyright (c) 2008 Nokia Corporation
============================================================================
    */

#ifndef CSENSORDATAFILTER_H_
#define CSENSORDATAFILTER_H_

#include <e32base.h>

// Size of sensor data ring buffers for the use of moving average filter.
// Smaller value gives quicker reaction speed to the changes in the sensor data
// but also the amplitude of the random noise from the physical sensor is higher.
const TInt KSensorBufferSize = 8;

class CSensorDataFilter : public CBase
    {
    public:
        /// Two-phased constructor
        static CSensorDataFilter* NewL( TInt aRingBufferSize );
        
        /// Destructor
        ~CSensorDataFilter();
        
    private:
        /// Second-phase constructor
        void ConstructL();
        
        /// Default constructor
        CSensorDataFilter( TInt aRingBufferSize );
        
    public:
        /// Calculates moving average value for given ring buffer
        TInt FilterSensorData( TInt aNewValue );
        
    private:
        TInt iRingBufferSize;
        TInt* iRingBuffer;
        TInt* iRingBufferPointer;
    };

#endif /*CSENSORDATAFILTER_H_*/