112 lines
3.7 KiB
C
112 lines
3.7 KiB
C
|
//===== Copyright <20> 1996-2005, Valve Corporation, All rights reserved. ======//
|
|||
|
//
|
|||
|
// Purpose: Random number generator
|
|||
|
//
|
|||
|
// $Workfile: $
|
|||
|
// $NoKeywords: $
|
|||
|
//===========================================================================//
|
|||
|
|
|||
|
#ifndef VSTDLIB_RANDOM_H
|
|||
|
#define VSTDLIB_RANDOM_H
|
|||
|
|
|||
|
#include "vstdlib/vstdlib.h"
|
|||
|
#include "tier0/basetypes.h"
|
|||
|
#include "tier0/threadtools.h"
|
|||
|
#include "tier1/interface.h"
|
|||
|
|
|||
|
#define NTAB 32
|
|||
|
|
|||
|
#pragma warning(push)
|
|||
|
#pragma warning( disable:4251 )
|
|||
|
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
// A generator of uniformly distributed random numbers
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
class IUniformRandomStream
|
|||
|
{
|
|||
|
public:
|
|||
|
// Sets the seed of the random number generator
|
|||
|
virtual void SetSeed( int iSeed ) = 0;
|
|||
|
|
|||
|
// Generates random numbers
|
|||
|
virtual float RandomFloat( float flMinVal = 0.0f, float flMaxVal = 1.0f ) = 0;
|
|||
|
virtual int RandomInt( int iMinVal, int iMaxVal ) = 0;
|
|||
|
virtual float RandomFloatExp( float flMinVal = 0.0f, float flMaxVal = 1.0f, float flExponent = 1.0f ) = 0;
|
|||
|
};
|
|||
|
|
|||
|
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
// The standard generator of uniformly distributed random numbers
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
class VSTDLIB_CLASS CUniformRandomStream : public IUniformRandomStream
|
|||
|
{
|
|||
|
public:
|
|||
|
CUniformRandomStream();
|
|||
|
|
|||
|
// Sets the seed of the random number generator
|
|||
|
virtual void SetSeed( int iSeed );
|
|||
|
|
|||
|
// Generates random numbers
|
|||
|
virtual float RandomFloat( float flMinVal = 0.0f, float flMaxVal = 1.0f );
|
|||
|
virtual int RandomInt( int iMinVal, int iMaxVal );
|
|||
|
virtual float RandomFloatExp( float flMinVal = 0.0f, float flMaxVal = 1.0f, float flExponent = 1.0f );
|
|||
|
|
|||
|
private:
|
|||
|
int GenerateRandomNumber();
|
|||
|
|
|||
|
int m_idum;
|
|||
|
int m_iy;
|
|||
|
int m_iv[NTAB];
|
|||
|
|
|||
|
CThreadFastMutex m_mutex;
|
|||
|
};
|
|||
|
|
|||
|
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
// A generator of gaussian distributed random numbers
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
class VSTDLIB_CLASS CGaussianRandomStream
|
|||
|
{
|
|||
|
public:
|
|||
|
// Passing in NULL will cause the gaussian stream to use the
|
|||
|
// installed global random number generator
|
|||
|
CGaussianRandomStream( IUniformRandomStream *pUniformStream = NULL );
|
|||
|
|
|||
|
// Attaches to a random uniform stream
|
|||
|
void AttachToStream( IUniformRandomStream *pUniformStream = NULL );
|
|||
|
|
|||
|
// Generates random numbers
|
|||
|
float RandomFloat( float flMean = 0.0f, float flStdDev = 1.0f );
|
|||
|
|
|||
|
private:
|
|||
|
IUniformRandomStream *m_pUniformStream;
|
|||
|
bool m_bHaveValue;
|
|||
|
float m_flRandomValue;
|
|||
|
|
|||
|
CThreadFastMutex m_mutex;
|
|||
|
};
|
|||
|
|
|||
|
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
// A couple of convenience functions to access the library's global uniform stream
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
VSTDLIB_INTERFACE void RandomSeed( int iSeed );
|
|||
|
VSTDLIB_INTERFACE float RandomFloat( float flMinVal = 0.0f, float flMaxVal = 1.0f );
|
|||
|
VSTDLIB_INTERFACE float RandomFloatExp( float flMinVal = 0.0f, float flMaxVal = 1.0f, float flExponent = 1.0f );
|
|||
|
VSTDLIB_INTERFACE int RandomInt( int iMinVal, int iMaxVal );
|
|||
|
VSTDLIB_INTERFACE float RandomGaussianFloat( float flMean = 0.0f, float flStdDev = 1.0f );
|
|||
|
|
|||
|
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
// Installs a global random number generator, which will affect the Random functions above
|
|||
|
//-----------------------------------------------------------------------------
|
|||
|
VSTDLIB_INTERFACE void InstallUniformRandomStream( IUniformRandomStream *pStream );
|
|||
|
|
|||
|
|
|||
|
#pragma warning(pop)
|
|||
|
|
|||
|
#endif // VSTDLIB_RANDOM_H
|
|||
|
|
|||
|
|
|||
|
|