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| author | Joe Ludwig <[email protected]> | 2013-06-26 15:22:04 -0700 |
|---|---|---|
| committer | Joe Ludwig <[email protected]> | 2013-06-26 15:22:04 -0700 |
| commit | 39ed87570bdb2f86969d4be821c94b722dc71179 (patch) | |
| tree | abc53757f75f40c80278e87650ea92808274aa59 /sp/src/public/vstdlib/random.h | |
| download | source-sdk-2013-39ed87570bdb2f86969d4be821c94b722dc71179.tar.xz source-sdk-2013-39ed87570bdb2f86969d4be821c94b722dc71179.zip | |
First version of the SOurce SDK 2013
Diffstat (limited to 'sp/src/public/vstdlib/random.h')
| -rw-r--r-- | sp/src/public/vstdlib/random.h | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/sp/src/public/vstdlib/random.h b/sp/src/public/vstdlib/random.h new file mode 100644 index 00000000..5c56eb12 --- /dev/null +++ b/sp/src/public/vstdlib/random.h @@ -0,0 +1,111 @@ +//========= Copyright 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
+
+
+
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