Perlin noise generator. More...

#include <perlin_noise.hpp>

Classes
struct	Vec2d
	Two dimensional vector. More...

Public Member Functions
	PerlinNoiseGenerator ()
	Default constructor. More...

	PerlinNoiseGenerator (float height, float width, unsigned int n_height, unsigned int n_width, unsigned long int seed=0)
	Constructor initialising the generator with the given parameters. More...

	~PerlinNoiseGenerator ()

void	configure (float height, float width, unsigned int n_height, unsigned int n_width, unsigned long int seed=0)
	Configures the generator. More...

void	randomise_gradients ()
	Fills the hash list with random gradients. More...

void	generate (unsigned long int seed=0)
	Populates the grid with random gradients from the hash list. More...

double	evaluate (float x, float y) const
	Evaluates the perlin noise at a given position. More...

float	accentuate (float x) const
	Applies a polynomial to accentuate the given value. More...

Private Member Functions
void	init_random (unsigned long int seed)
	Initialises random generation. More...

float	dot_product (Vec2d u, Vec2d v) const
	Computes the dot product between two vectors. More...

float	dot_dist_grad (unsigned int i, unsigned int j, float x, float y) const
	Compute the dot product of the distance vector to the node an the gradient at this node. More...

float	interpolate (float a, float b, float t) const
	Linear interpolation between two values. More...

float	fade (float t) const
	Sixth order polynomial to smooth the noise. More...

Private Attributes
float	height_
	Height of the 2D space in which to generate the noise. More...

float	width_
	Width of the 2D space in which to generate the noise. More...

unsigned int	n_height_
	Size of the discretised grid in the first dimension. More...

unsigned int	n_width_
	Size of the discretised grid in the second dimension. More...

std::vector< std::vector< Vec2d > >	gradients_
	Gradients evaluated at nodes of the grid. More...

std::vector< Vec2d >	hash_gradients_
	Hash list of random gradients. More...

bool	randomise_seed_
	Whether to randomise seeding for random numbers. More...

unsigned long int	seed_
	Seed for random numbers when no random seeding. More...

std::random_device	random_device_
	Seed initialiser for generation of random numbers. More...

Detailed Description

Perlin noise generator.

Definition at line 21 of file perlin_noise.hpp.

Constructor & Destructor Documentation

mfcpp::PerlinNoiseGenerator::PerlinNoiseGenerator ( )

Default constructor.

Definition at line 56 of file perlin_noise.cpp.

mfcpp::PerlinNoiseGenerator::PerlinNoiseGenerator	(	float	height,
		float	width,
		unsigned int	n_height,
		unsigned int	n_width,
		unsigned long int	seed = `0`
	)

Constructor initialising the generator with the given parameters.

Parameters

height	Height of the 2D space in which to generate the noise
width	Width of the 2D space in which to generate the noise
n_height	Size of the discretised grid in the first dimension
n_width	Size of the discretised grid in the second dimensio
seed	Seed for randomisation (0 for random seeding)

Definition at line 67 of file perlin_noise.cpp.

mfcpp::PerlinNoiseGenerator::~PerlinNoiseGenerator ( )

Definition at line 80 of file perlin_noise.cpp.

Member Function Documentation

float mfcpp::PerlinNoiseGenerator::accentuate ( float x ) const

inline

Applies a polynomial to accentuate the given value.

Values under 0.5 are pushed towards 0, while values above 0.5 are pushed towards 1.

Parameters

x	Given value

Returns: Accentuated value

Definition at line 195 of file perlin_noise.hpp.

void mfcpp::PerlinNoiseGenerator::configure	(	float	height,
		float	width,
		unsigned int	n_height,
		unsigned int	n_width,
		unsigned long int	seed = `0`
	)

Configures the generator.

Parameters

height	Height of the 2D space in which to generate the noise
width	Width of the 2D space in which to generate the noise
n_height	Size of the discretised grid in the first dimension
n_width	Size of the discretised grid in the second dimension
seed	Seed for randomisation (0 for random seeding)

Definition at line 86 of file perlin_noise.cpp.

float mfcpp::PerlinNoiseGenerator::dot_dist_grad	(	unsigned int	i,
		unsigned int	j,
		float	x,
		float	y
	)		const

private

Compute the dot product of the distance vector to the node an the gradient at this node.

Parameters

i	Index of the node for the first dimension
j	Index of the node for the second dimension
x	First coordinate of the evaluated point
y	Second coordinate of the evaluated point

Definition at line 210 of file perlin_noise.cpp.

float mfcpp::PerlinNoiseGenerator::dot_product	(	Vec2d	u,
		Vec2d	v
	)		const

private

Computes the dot product between two vectors.

Parameters

u	First vector
v	Second vector

Returns: Dot product between u and v

Definition at line 204 of file perlin_noise.cpp.

double mfcpp::PerlinNoiseGenerator::evaluate	(	float	x,
		float	y
	)		const

Evaluates the perlin noise at a given position.

Parameters

x	First coordinate where to evaluate
y	Second coordinate where to evaluate

Returns: Perlin noise value at (x, y)

Definition at line 152 of file perlin_noise.cpp.

float mfcpp::PerlinNoiseGenerator::fade ( float t ) const

inlineprivate

Sixth order polynomial to smooth the noise.

Parameters

t	Number between 0 and 1

Returns: 6t^5 - 15t^4 + 10t^3

Definition at line 189 of file perlin_noise.hpp.

void mfcpp::PerlinNoiseGenerator::generate ( unsigned long int seed = 0 )

Populates the grid with random gradients from the hash list.

Parameters

seed	Seed for randomisation (0 for random seeding)

Definition at line 128 of file perlin_noise.cpp.

void mfcpp::PerlinNoiseGenerator::init_random ( unsigned long int seed )

private

Initialises random generation.

Parameters

seed	Seed to use for initialisation. If 0, random seeding

Definition at line 192 of file perlin_noise.cpp.

float mfcpp::PerlinNoiseGenerator::interpolate	(	float	a,
		float	b,
		float	t
	)		const

private

Linear interpolation between two values.

Parameters

a	First value to interpolate
b	Second value to interpolate
t	Interpolation ratio

Returns: Interpolation between a and b

Definition at line 220 of file perlin_noise.cpp.

void mfcpp::PerlinNoiseGenerator::randomise_gradients ( )

Fills the hash list with random gradients.

Definition at line 99 of file perlin_noise.cpp.

Member Data Documentation

std::vector<std::vector<Vec2d> > mfcpp::PerlinNoiseGenerator::gradients_

private

Gradients evaluated at nodes of the grid.

Definition at line 124 of file perlin_noise.hpp.

std::vector<Vec2d> mfcpp::PerlinNoiseGenerator::hash_gradients_

private

Hash list of random gradients.

Definition at line 127 of file perlin_noise.hpp.

float mfcpp::PerlinNoiseGenerator::height_

private

Height of the 2D space in which to generate the noise.

Definition at line 112 of file perlin_noise.hpp.

unsigned int mfcpp::PerlinNoiseGenerator::n_height_

private

Size of the discretised grid in the first dimension.

Definition at line 118 of file perlin_noise.hpp.

unsigned int mfcpp::PerlinNoiseGenerator::n_width_

private

Size of the discretised grid in the second dimension.

Definition at line 121 of file perlin_noise.hpp.

std::random_device mfcpp::PerlinNoiseGenerator::random_device_

private

Seed initialiser for generation of random numbers.

Definition at line 136 of file perlin_noise.hpp.

bool mfcpp::PerlinNoiseGenerator::randomise_seed_

private

Whether to randomise seeding for random numbers.

Definition at line 130 of file perlin_noise.hpp.

unsigned long int mfcpp::PerlinNoiseGenerator::seed_

private

Seed for random numbers when no random seeding.

Definition at line 133 of file perlin_noise.hpp.

float mfcpp::PerlinNoiseGenerator::width_

private

Width of the 2D space in which to generate the noise.

Definition at line 115 of file perlin_noise.hpp.

The documentation for this class was generated from the following files:

/home/corentin/thesis_ws/src/marine-farm-cpp/mf_common/include/mf_common/perlin_noise.hpp
/home/corentin/thesis_ws/src/marine-farm-cpp/mf_common/src/mf_common/perlin_noise.cpp

MFCPP 1.0	Corentin Chauvin-Hameau – 2019-2020
Coverage Path Planning for an underwater robot surveying a marine farm

Classes

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation