noise.c File Reference

#include "common.h"
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "machine.h"
#include "bu.h"
#include "vmath.h"
#include "bn.h"

Include dependency graph for noise.c:

Go to the source code of this file.

Data Structures
struct	str_ht
struct	fbm_spec
Defines
#define	SMOOTHSTEP(x)   ( (x) * (x) * (3 - 2*(x)) )
	interpolate smoothly from 0 .. 1 SMOOTHSTEP() takes a value in the range [0:1] and provides a number in the same range indicating the amount of (a) present in a smooth interpolation transition between (a) and (b)
#define	FLOOR(x)   ( (int)(x) - ( (x) < 0 && (x) != (int)(x) ) )
#define	MAXSIZE   267
#define	INCRSUM(m, s, x, y, z)
#define	MAGIC_STRHT1   1771561
#define	MAGIC_STRHT2   1651771
#define	MAGIC_TAB1   9823
#define	MAGIC_TAB2   784642
#define	CK_HT()
#define	Hash3d(a, b, c)
#define	MAGIC_fbm_spec_wgt   0x837592
#define	PSCALE(_p, _s)   _p[0] *= _s; _p[1] *= _s; _p[2] *= _s
#define	PCOPY(_d, _s)   _d[0] = _s[0]; _d[1] = _s[1]; _d[2] = _s[2]
#define	CACHE_SPECTRAL_WGTS   1
Functions
void	bn_noise_init (void)
double	bn_noise_perlin (fastf_t *point)
	Robert Skinner's Perlin-style "Noise" function.
void	bn_noise_vec (fastf_t *point, fastf_t *result)
fbm_spec *	find_spec_wgt (double h, double l, double o)
double	bn_noise_fbm (fastf_t *point, double h_val, double lacunarity, double octaves)
	Procedural fBm evaluated at "point"; returns value stored in "value".
double	bn_noise_turb (fastf_t *point, double h_val, double lacunarity, double octaves)
	Procedural turbulence evaluated at "point";.
double	bn_noise_ridged (fastf_t *point, double h_val, double lacunarity, double octaves, double offset)
	A ridged noise pattern.
double	bn_noise_mf (fastf_t *point, double h_val, double lacunarity, double octaves, double offset)

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Detailed Description

Signed noise functions

• bn_noise_perlin Robert Skinner's Perlin-style "Noise" function
• bn_noise_vec Vector-valued noise

Spectral Noise functions

• bn_noise_fbm fractional Brownian motion. Based on bn_noise_perlin
• bn_noise_turb turbulence. Based on bn_noise_perlin

These noise functions provide mostly random noise at the integer lattice points. The functions should be evaluated at non-integer locations for their nature to be realized.

Author:

Lee A. Butler

Contributed code from

F. Kenton Musgrave
Robert Skinner

Source -

The U. S. Army Research Laboratory @ Aberdeen Proving Ground, Maryland 21005-5068 USA

Definition in file noise.c.

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Define Documentation

#define CACHE_SPECTRAL_WGTS   1

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