#pragma once

struct RandomGenerator
{
	float getRand()
	{
		return 2.0f * ( genFloat() - 0.5f );
	}

	float getRand( float a, float b )
	{
		return genFloat( a, b );
	}

	int getRandInt( int a, int b )
	{
		return genInteger( a, b );		
	}

		enum RandConstants 
	{                     
		KK = 17, 
		JJ = 10, 
		R1 = 13, 
		R2 =  9 
	};

	int g_iP1;
	int g_iP2;

	unsigned g_u32Buffer[ KK ];

	float genFloat()
	{
		unsigned int u32Tmp;
		// nächste Zahl
		u32Tmp= _lrotl( g_u32Buffer[ g_iP2 ], R1 ) + 
			_lrotl( g_u32Buffer[ g_iP1 ], R2 );
		g_u32Buffer[ g_iP1 ]= u32Tmp;

		// Listen rotieren
		g_iP1--;
		if ( g_iP1 < 0 ) 
		{ 
			g_iP1 = KK - 1;
		}

		g_iP2--;
		if ( g_iP2 < 0 ) 
		{
			g_iP2 = KK - 1;
		}

		// conversion to float:
		union 
		{
			double f; 
			unsigned long i[2];
		} convert;

		convert.i[0] =  u32Tmp << 20;
		convert.i[1] = ( u32Tmp >> 12 ) | 0x3FF00000;
		return (float)( convert.f - 1.0f );

	}
	
	unsigned int getLastTempValue()
	{
		return g_u32Buffer[ g_iP1 ];
	}

	void setSeed( unsigned int Seed )
	{
		int i;

		// Buffer füllen
		for( i= 0; i < KK; i++ )
		{
			Seed= Seed * 2891336453 + 1;
			g_u32Buffer[ i ] = Seed;
		}

		// Pointer initialisieren
		g_iP1= 0;
		g_iP2= JJ;

		// Anfang der Folge wegwerfen
		for( i= 0; i < 9; i++ )
		{
			genFloat();
		}
	}

	int genInteger(	int iMin, int iMax )
	{
		float fInterval = (float)( iMax - iMin ) + 0.96875f;
		float fRet= fInterval * genFloat();
		fRet+= (float)iMin;
		int iRet= (int)( fRet - 0.484375f );
		//int iRet= (int)( fRet );
		assert( iRet >= iMin );
		assert( iRet <= iMax );
		return iRet;
	}

	float genFloat( float fMin, float fMax )
	{
		float fInterval = (float)( fMax - fMin );

		return fMin + fInterval * genFloat();
	}
};