RandGenerator Class Reference

#include <randgenerator.h>

Class Description

class RandGenerator

Description:

This class has interfaces for srand() and rand() methods of VC++ and other functions for random number generation. The srand() and rand() methods from stdlib.h have two main problems:

a) It's not satisfactorily random. The rand() function returns a pseudorandom integer in the range 0 to 0x7fff=32767. If we need a lot of random numbers using rand() (i.e. for generating 100,000 particles), we run out of continuity of random numbers. Generated random numbers becomes too discrete.

b) The rand() method is global function, not class object. Hence it is shared between all modules of your plug-in. Changes in one module may change randomness pattern in other independent module. To solve this contradiction, rand methods have to be implemented as a class object.

The RandGenerator does exactly that. It has much more random numbers: RAND_MAX = 0xFFFFFFFF = 4,294,967,295. Also, using instances of the class, it's much easier to create separate threads of random numbers for a specific module.

Data Members:

static const DWORD32 RAND_MAX

This definition is used to override the VC++ rand methods.

Inheritance diagram for RandGenerator:

Public Member Functions
CoreExport	RandGenerator ()
CoreExport void	srand (DWORD32 seed)
CoreExport DWORD32	rand (void)
CoreExport int	RandSign (void)
CoreExport float	Rand01 (void)
CoreExport float	Rand11 (void)
CoreExport float	Rand55 (void)
CoreExport int	Rand0X (int maxnum)
const bool	Valid (void) const

Static Public Attributes
static CoreExport const DWORD32	RAND_MAX

Additional Inherited Members
Static Public Member Functions inherited from MaxHeapOperators
static UtilExport void *	operator new (size_t size)
	Standard new operator used to allocate objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e)
	Standard new operator used to allocate objects if there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new (size_t size, const char *filename, int line)
	New operator used to allocate objects that takes the filename and line number where the new was called If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, int block_type, const char *filename, int line)
	New operator used to allocate objects that takes the type of memory, filename and line number where the new was called If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e, const char *filename, int line)
	New operator used to allocate objects that takes the filename and line number where the new was called If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new (size_t size, unsigned long flags)
	New operator used to allocate objects that takes extra flags to specify special operations If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e, unsigned long flags)
	New operator used to allocate objects that takes extra flags to specify special operations If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size, const char *filename, int line)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, int block_type, const char *filename, int line)
	New operator used to allocate arrays of objects. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e, const char *filename, int line)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size, unsigned long flags)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e, unsigned long flags)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void	operator delete (void *ptr)
	Standard delete operator used to deallocate an object If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e)
	Standard delete operator used to deallocate an object If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete (void *ptr, const char *filename, int line)
	Delete operator used to deallocate an object that takes the filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, int block_type, const char *filename, int line)
	Delete operator used to deallocate an object that takes the type of memory, filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e, const char *filename, int line)
	Delete operator used to deallocate an object that takes the filename and line number where the delete was called If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete (void *ptr, unsigned long flags)
	Delete operator used to deallocate an object that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e, unsigned long flags)
	Delete operator used to deallocate an object that takes extra flags to specify special operations If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr)
	Standard delete operator used to deallocate an array of objects If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e)
	Standard delete operator used to deallocate an array of objects If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, int block_type, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the type of memory, filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the filename and line number where the delete was called If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr, unsigned long flags)
	Delete operator used to deallocate an array of objects that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e, unsigned long flags)
	Delete operator used to deallocate an array of objects that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, void *placement_ptr)
	Placement new operator. More...
static UtilExport void	operator delete (void *ptr, void *placement_ptr)
	Placement delete operator. More...
static UtilExport void *	aligned_malloc (size_t size, size_t alignment)
	Allocates memory on a specified alignment boundary. More...
static UtilExport void *	aligned_realloc (void *ptr, size_t size, size_t alignment)
	Reallocates memory on a specified alignment boundary. More...
static UtilExport void	aligned_free (void *ptr)
	Frees a block of memory that was allocated with aligned_malloc/aligned_realloc. More...

Constructor & Destructor Documentation

CoreExport RandGenerator

(

)

Remarks

Constructor.

Member Function Documentation

CoreExport void srand

(

DWORD32

seed

)

Remarks

This method sets the starting point for generating a series of pseudorandom integers. To reinitialize the generator, use 1 as the seed argument. Any other value for seed sets the generator to a random starting point. rand() retrieves the pseudorandom numbers that are generated. Calling rand() before any call to this method generates the same sequence as calling it with seed passed as 1.

Parameters:

DWORD32 seed

The starting seed.

CoreExport DWORD32 rand

(

void

)

Remarks

This method returns a pseudorandom integer in the range 0 to RAND_MAX

CoreExport int RandSign

(

void

)

Remarks

This method returns the random number sign, either -1 or 1.

CoreExport float Rand01

(

void

)

Remarks

This method return a random number between 0.0f and 1.0f.

CoreExport float Rand11

(

void

)

Remarks

This method return a random number between -1.0f and 1.0f.

CoreExport float Rand55

(

void

)

Remarks

This method return a random number between -0.5f and 0.5f.

CoreExport int Rand0X

(

int

maxnum

)

Remarks

This method return a random number between 0 and maxnum.

const bool Valid ( void  ) const

inline

Remarks

This method returns TRUE if the random number generator has been explicitly initialized by the srand() method.

                                        { 
            return m_explicitelyInitialized; 
        }

Member Data Documentation

CoreExport const DWORD32 RAND_MAX

static