math
[proland]

Provides utility math functions. More...

Classes
struct	proland::seg2< type >
	A 2D segment. More...
Functions
PROLAND_API vec3f	proland::rgb2hsl (const vec3f &rgb)
	Converts a color from rgb space to hsl space.
PROLAND_API vec3f	proland::hsl2rgb (const vec3f &hsl)
	Converts a color from hsl space to rgb space.
PROLAND_API mat3f	proland::dcolor (const vec3f &rgb, const vec3f &amp=vec3f(1/12.0f, 1/3.0f, 1/6.0f))
	Computes the derivates of an rgb color with respect to hsl coordinates.
template<typename type >
type	proland::cross (const vec2< type > u, const vec2< type > &v)
	Returns the z coordinate of the cross product of this vector and of the given vector.
template<typename type >
bool	proland::clipPoint (const box2< type > &box, const vec2< type > &a)
	Returns true if the given point is inside this bounding box.
template<typename type >
bool	proland::clipRectangle (const box2< type > &box, const box2< type > &a)
	Returns true if the given box is inside or intersects this bounding box.
template<typename type >
bool	proland::intersects (const box2< type > &box, const box2< type > &a)
	Alias for clipRectangle.
template<typename type >
bool	proland::clipSegment (const box2< type > &box, const vec2< type > &a, const vec2< type > &b)
	Returns true if the given segment is inside or may intersect this bounding box.
template<typename type >
bool	proland::clipQuad (const box2< type > &box, const vec2< type > &a, const vec2< type > &b, const vec2< type > &c)
	Returns true if the given quadratic Bezier arc is inside or may intersect this bounding box.
template<typename type >
bool	proland::clipCubic (const box2< type > &box, const vec2< type > &a, const vec2< type > &b, const vec2< type > &c, const vec2< type > &d)
	Returns true if the given cubic Bezier arc is inside or may intersect this bounding box.
PROLAND_API long	proland::lrandom (long *seed)
	Returns a pseudo random integer in the range 0-2147483647.
PROLAND_API float	proland::frandom (long *seed)
	Returns a pseudo random float number in the range 0-1.
PROLAND_API float	proland::grandom (float mean, float stdDeviation, long *seed)
	Returns a pseudo random float number with a Gaussian distribution.
PROLAND_API float	proland::cnoise (float x, float y, int P=0)
	Computes the classic 2D Perlin noise function.
PROLAND_API float	proland::cnoise (float x, float y, float z, int P=0)
	Computes the classic 3D Perlin noise function.
PROLAND_API float	proland::snoise (float x, float y, int P=0)
	Computes the 2D Perlin simplex noise function.
PROLAND_API float	proland::snoise (float x, float y, float z, int P=0)
	Computes the 3D Perlin simplex noise function.
PROLAND_API float	proland::snoise (float x, float y, float z, float w, int P=0)
	Computes the 4D Perlin simplex noise function.
PROLAND_API float *	proland::buildFbm4NoiseTexture2D (int size, int freq, int octaves, int lacunarity, float gain)
	Computes a 2D Fbm noise function in a 2D float array.
PROLAND_API float *	proland::buildFbm1NoiseTexture3D (int size, int freq, int octaves, int lacunarity, float gain)
	Computes a 3D Fbm noise function in a 3D float array.

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Detailed Description

Provides utility math functions.

---

Function Documentation

PROLAND_API float* proland::buildFbm1NoiseTexture3D	(	int	size,
		int	freq,
		int	octaves,
		int	lacunarity,
		float	gain
	)

Computes a 3D Fbm noise function in a 3D float array.

This function is a sum of several Perlin noise function with different frequencies and amplitudes.

Parameters:

	size	the width, height and depth of the array of values to be computed.
	freq	the pseudo frequency of the lower frequency noise function. The corresponding pseudo period in pixels is size/freq.
	octaves	the number of Perlin noise functions to add.
	lacunarity	the frequency factor between each noise function.
	gain	the amplitude factor between each noise function.

Returns:

the computed size*size*size array of values. These values are normalized to stay in the range 0-1.

PROLAND_API float* proland::buildFbm4NoiseTexture2D	(	int	size,
		int	freq,
		int	octaves,
		int	lacunarity,
		float	gain
	)

Computes a 2D Fbm noise function in a 2D float array.

This function is a sum of several Perlin noise function with different frequencies and amplitudes.

Parameters:

	size	the width and height of the array of values to be computed.
	freq	the pseudo frequency of the lower frequency noise function. The corresponding pseudo period in pixels is size/freq.
	octaves	the number of Perlin noise functions to add.
	lacunarity	the frequency factor between each noise function.
	gain	the amplitude factor between each noise function.

Returns:

the computed size*size array of values. These values are normalized to stay in the range 0-1.

template<typename type >

bool proland::clipCubic	(	const box2< type > &	box,
		const vec2< type > &	a,
		const vec2< type > &	b,
		const vec2< type > &	c,
		const vec2< type > &	d
	)			[inline]

Returns true if the given cubic Bezier arc is inside or may intersect this bounding box.

Parameters:

	a	Bezier arc extremity.
	b	first Bezier arc control point.
	c	second Bezier arc control point.
	d	the other Bezier arc extremity.

template<typename type >

bool proland::clipPoint	(	const box2< type > &	box,
		const vec2< type > &	a
	)			[inline]

Returns true if the given point is inside this bounding box.

Parameters:

a

an arbitrary point.

template<typename type >

bool proland::clipQuad	(	const box2< type > &	box,
		const vec2< type > &	a,
		const vec2< type > &	b,
		const vec2< type > &	c
	)			[inline]

Returns true if the given quadratic Bezier arc is inside or may intersect this bounding box.

Parameters:

	a	Bezier arc extremity.
	b	Bezier arc control point.
	c	the other Bezier arc extremity.

template<typename type >

bool proland::clipRectangle	(	const box2< type > &	box,
		const box2< type > &	a
	)			[inline]

Returns true if the given box is inside or intersects this bounding box.

Parameters:

a

an arbitrary bounding box.

template<typename type >

bool proland::clipSegment	(	const box2< type > &	box,
		const vec2< type > &	a,
		const vec2< type > &	b
	)			[inline]

Returns true if the given segment is inside or may intersect this bounding box.

Parameters:

	a	a segment extremity.
	b	the other segment extremity.

PROLAND_API float proland::cnoise	(	float	x,
		float	y,
		float	z,
		int	P = 0
	)

Computes the classic 3D Perlin noise function.

Parameters:

	x	the x coordinate of the point where the function must be evaluated.
	y	the y coordinate of the point where the function must be evaluated.
	z	the z coordinate of the point where the function must be evaluated.
	P	an optional period to get a periodic noise function. The default value 0 means a non periodic function.

Returns:

the classic 3D Perlin noise function evaluated at (x,y,z). This function has a main frequency of 1, and its value are between -1 and 1.

PROLAND_API float proland::cnoise	(	float	x,
		float	y,
		int	P = 0
	)

Computes the classic 2D Perlin noise function.

Parameters:

	x	the x coordinate of the point where the function must be evaluated.
	y	the y coordinate of the point where the function must be evaluated.
	P	an optional period to get a periodic noise function. The default value 0 means a non periodic function.

Returns:

the classic 2D Perlin noise function evaluated at (x,y). This function has a main frequency of 1, and its value are between -1 and 1.

template<typename type >

type proland::cross	(	const vec2< type >	u,
		const vec2< type > &	v
	)			[inline]

Returns the z coordinate of the cross product of this vector and of the given vector.

PROLAND_API mat3f proland::dcolor	(	const vec3f &	rgb,
		const vec3f &	amp = vec3f(1/12.0f, 1/3.0f, 1/6.0f)
	)

Computes the derivates of an rgb color with respect to hsl coordinates.

Parameters:

	rgb	a color in rgb space.
	amp	scaling factors for each partial derivative.

Returns:

a matrix whose columns correspond to the partial derivatives drgb/dh, drgb/ds and drgb/dl, scaled by the factors amp.x, amp.y and amp.z.

PROLAND_API float proland::frandom

(

long *

seed

)

[inline]

Returns a pseudo random float number in the range 0-1.

Parameters:

the

seed used by this pseudo random generator. It is modified each time this function is called.

Returns:

a pseudo random float number in the range 0-1.

PROLAND_API float proland::grandom	(	float	mean,
		float	stdDeviation,
		long *	seed
	)			[inline]

Returns a pseudo random float number with a Gaussian distribution.

Parameters:

	mean	the mean of the Gaussian distribution.
	stdDeviation	the standard deviation of the Gaussian distribution (square root of its variance).
	the	seed used by this pseudo random generator. It is modified each time this function is called.

Returns:

a pseudo random float number with the given Gaussian distribution.

PROLAND_API vec3f proland::hsl2rgb

(

const vec3f &

hsl

)

Converts a color from hsl space to rgb space.

Color coordinates in [0,1]

template<typename type >

bool proland::intersects	(	const box2< type > &	box,
		const box2< type > &	a
	)			[inline]

Alias for clipRectangle.

PROLAND_API long proland::lrandom

(

long *

seed

)

[inline]

Returns a pseudo random integer in the range 0-2147483647.

Parameters:

the

seed used by this pseudo random generator. It is modified each time this function is called.

Returns:

a peudo random integer in the range 0-2147483647.

PROLAND_API vec3f proland::rgb2hsl

(

const vec3f &

rgb

)

Converts a color from rgb space to hsl space.

Color coordinates in [0,1]

PROLAND_API float proland::snoise	(	float	x,
		float	y,
		float	z,
		float	w,
		int	P = 0
	)

Computes the 4D Perlin simplex noise function.

Parameters:

	x	the x coordinate of the point where the function must be evaluated.
	y	the y coordinate of the point where the function must be evaluated.
	z	the z coordinate of the point where the function must be evaluated.
	w	the w coordinate of the point where the function must be evaluated.
	P	an optional period to get a periodic noise function. The default value 0 means a non periodic function.

Returns:

the 4D Perlin simplex noise function evaluated at (x,y,z,w). This function has a main frequency of 1, and its value are between -1 and 1.

PROLAND_API float proland::snoise	(	float	x,
		float	y,
		float	z,
		int	P = 0
	)

Computes the 3D Perlin simplex noise function.

Parameters:

	x	the x coordinate of the point where the function must be evaluated.
	y	the y coordinate of the point where the function must be evaluated.
	z	the z coordinate of the point where the function must be evaluated.
	P	an optional period to get a periodic noise function. The default value 0 means a non periodic function.

Returns:

the 3D Perlin simplex noise function evaluated at (x,y,z). This function has a main frequency of 1, and its value are between -1 and 1.

PROLAND_API float proland::snoise	(	float	x,
		float	y,
		int	P = 0
	)

Computes the 2D Perlin simplex noise function.

Parameters:

	x	the x coordinate of the point where the function must be evaluated.
	y	the y coordinate of the point where the function must be evaluated.
	P	an optional period to get a periodic noise function. The default value 0 means a non periodic function.

Returns:

the 2D Perlin simplex noise function evaluated at (x,y). This function has a main frequency of 1, and its value are between -1 and 1.