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#if !defined(__CABasicSineOscillator_h__)
#define __CABasicSineOscillator_h__

//==================================================================================================
//	Includes
//==================================================================================================

//	System Includes
#include <math.h>

//==================================================================================================
//	CABasicSineOscillator
//
//	A sine wave oscillator that uses an iterative function to calculate sine but does not support
//	modulation of any kind.
//==================================================================================================

class CABasicSineOscillator
{

//	Construction/Destruction
public:
	CABasicSineOscillator(double inSampleRate, double inFrequency, double inVolumeScalar)
	:
		mSampleRate(inSampleRate),
		mFrequency(inFrequency),
		mVolumeScalar(inVolumeScalar),
		mOmega(0),
		mB(0),
		mY1(0),
		mY2(0)
	{ 
		Reset();
	}
	
	~CABasicSineOscillator()
	{
	}

//	Operations
public:
	double	NextValue()
	{
		double theAnswer = (mB * mY1) - mY2;
		mY2 = mY1;
		mY1 = theAnswer;
		return mVolumeScalar * theAnswer;
	}
	
	void	Reset()
	{
		mOmega = (2 * M_PI * mFrequency) / mSampleRate;
		mB = 2 * cos(mOmega);
		mY1 = 0;
		mY2 = sin(-mOmega);
	}

//	Implementation
private:
	double	mSampleRate;
	double	mFrequency;
	double	mVolumeScalar;
	double	mOmega;
	double	mB;
	double	mY1;
	double	mY2;

};

#endif
