Infinity::Engine::UniformRealDistribution< RealType > Class Template Reference

Platform-independent uniform real distribution. More...

#include <PRNGDistribution.hpp>

Classes
struct	param_type
	Parameter set for the distribution. More...

Public Types
using	result_type = RealType
	The type of values produced by the distribution.

Public Member Functions
	UniformRealDistribution ()
	Default constructor. Creates a uniform distribution over [0, 1).
	UniformRealDistribution (RealType a, RealType b=RealType(1))
	Constructs a uniform distribution with specified bounds.
	UniformRealDistribution (const param_type &param)
	Constructs from a parameter set.
void	reset ()
	Resets the distribution state.
RealType	a () const
	Gets the lower bound of the distribution range.
RealType	b () const
	Gets the upper bound of the distribution range.
param_type	param () const
	Gets the current parameter set.
void	param (const param_type &param)
	Sets new parameters for the distribution.
result_type	min () const
	Gets the minimum value that can be generated (inclusive).
result_type	max () const
	Gets the maximum value that can be generated (exclusive).
template<typename Generator >
result_type	operator() (Generator &g)
	Generates the next random value using stored parameters.
template<typename Generator >
result_type	operator() (Generator &g, const param_type &param)
	Generates the next random value using provided parameters.

Friends
bool	operator== (const UniformRealDistribution &lhs, const UniformRealDistribution &rhs)
bool	operator!= (const UniformRealDistribution &lhs, const UniformRealDistribution &rhs)

Detailed Description

template<typename RealType = double>
class Infinity::Engine::UniformRealDistribution< RealType >

Platform-independent uniform real distribution.

Produces floating-point values uniformly distributed over a specified range [a, b). Unlike std::uniform_real_distribution, this implementation guarantees identical results across different platforms and compilers by using a deterministic uint32 to float conversion method.

This distribution is essential for procedural generation where cross-platform reproducibility is critical. The same seed will produce identical sequences on Windows, Linux, and macOS regardless of compiler or standard library implementation.

Template Parameters

RealType

Floating point type (float or double)

Example usage:

PRNG rng(12345);
UniformRealDistribution<float> dist(0.0f, 10.0f);
 
float value = dist(rng);  // Random float in [0, 10)
 
// Generate multiple values
for (int i = 0; i < 100; ++i) {
    float x = dist(rng);
}
 
// Change parameters without creating new distribution
dist.param(UniformRealDistribution<float>::param_type(-1.0f, 1.0f));
float normalized = dist(rng);  // Now in [-1, 1)

Note

Results are guaranteed identical across platforms when using the same PRNG seed.

Warning

The upper bound b is exclusive; values are in [a, b), not [a, b].

Member Typedef Documentation

result_type

template<typename RealType = double>

using Infinity::Engine::UniformRealDistribution< RealType >::result_type = RealType

The type of values produced by the distribution.

Constructor & Destructor Documentation

UniformRealDistribution() [1/3]

template<typename RealType = double>

Infinity::Engine::UniformRealDistribution< RealType >::UniformRealDistribution ( )

inline

Default constructor. Creates a uniform distribution over [0, 1).

UniformRealDistribution() [2/3]

template<typename RealType = double>

Infinity::Engine::UniformRealDistribution< RealType >::UniformRealDistribution ( RealType  a, RealType  b = RealType(1)  )

inlineexplicit

Constructs a uniform distribution with specified bounds.

Parameters

a	Lower bound (inclusive)
b	Upper bound (exclusive), defaults to 1

UniformRealDistribution() [3/3]

template<typename RealType = double>

Infinity::Engine::UniformRealDistribution< RealType >::UniformRealDistribution ( const param_type &  param )

inlineexplicit

Constructs from a parameter set.

Parameters

param

The distribution parameters

Member Function Documentation

a()

template<typename RealType = double>

RealType Infinity::Engine::UniformRealDistribution< RealType >::a ( ) const

inline

Gets the lower bound of the distribution range.

b()

template<typename RealType = double>

RealType Infinity::Engine::UniformRealDistribution< RealType >::b ( ) const

inline

Gets the upper bound of the distribution range.

max()

template<typename RealType = double>

result_type Infinity::Engine::UniformRealDistribution< RealType >::max ( ) const

inline

Gets the maximum value that can be generated (exclusive).

min()

template<typename RealType = double>

result_type Infinity::Engine::UniformRealDistribution< RealType >::min ( ) const

inline

Gets the minimum value that can be generated (inclusive).

operator()() [1/2]

template<typename RealType = double>

template<typename Generator >

result_type Infinity::Engine::UniformRealDistribution< RealType >::operator() ( Generator &  g )

inline

Generates the next random value using stored parameters.

Template Parameters

Generator

The random number generator type (e.g., PRNG)

Parameters

g	The random number generator

Returns

A random value uniformly distributed in [a, b)

operator()() [2/2]

template<typename RealType = double>

template<typename Generator >

result_type Infinity::Engine::UniformRealDistribution< RealType >::operator() ( Generator &  g, const param_type &  param  )

inline

Generates the next random value using provided parameters.

Uses a deterministic conversion from uint32 to floating point that ensures identical results across all platforms and compilers. The conversion divides by exactly 2^32 to map the full uint32 range to [0, 1).

Template Parameters

Generator

The random number generator type (e.g., PRNG)

Parameters

g	The random number generator
param	The distribution parameters to use for this generation

Returns

A random value uniformly distributed in [param.a(), param.b())

param() [1/2]

template<typename RealType = double>

param_type Infinity::Engine::UniformRealDistribution< RealType >::param ( ) const

inline

Gets the current parameter set.

param() [2/2]

template<typename RealType = double>

void Infinity::Engine::UniformRealDistribution< RealType >::param ( const param_type &  param )

inline

Sets new parameters for the distribution.

reset()

template<typename RealType = double>

void Infinity::Engine::UniformRealDistribution< RealType >::reset ( )

inline

Resets the distribution state.

No-op for uniform distributions as they maintain no internal state between generations.

Friends And Related Symbol Documentation

operator!=

template<typename RealType = double>

bool operator!= ( const UniformRealDistribution< RealType > &  lhs, const UniformRealDistribution< RealType > &  rhs  )

friend

operator==

template<typename RealType = double>

bool operator== ( const UniformRealDistribution< RealType > &  lhs, const UniformRealDistribution< RealType > &  rhs  )

friend