perlin.c File Reference

Perlin Noise generator, based on code from: https://adrianb.io/2014/08/09/perlinnoise.html. More...

#include <math.h>
#include "libavutil/lfg.h"
#include "libavutil/random_seed.h"
#include "perlin.h"

Go to the source code of this file.

Functions
static int	inc (int num, int period)
static double	grad (int hash, double x, double y, double z)
static double	fade (double t)
static double	lerp (double a, double b, double x)
int	ff_perlin_init (FFPerlin *perlin, double period, int octaves, double persistence, enum FFPerlinRandomMode random_mode, unsigned int random_seed)
	Initialize the Perlin noise generator with parameters.
static double	perlin_get (FFPerlin *perlin, double x, double y, double z)
double	ff_perlin_get (FFPerlin *perlin, double x, double y, double z)
	Compute Perlin noise given the x, y, z coordinates.

Variables
static uint8_t	ken_permutations []

Detailed Description

Perlin Noise generator, based on code from: https://adrianb.io/2014/08/09/perlinnoise.html.

Original article from Ken Perlin: http://mrl.nyu.edu/~perlin/paper445.pdf

Definition in file perlin.c.

Function Documentation

inc()

static int inc ( int num, int period )

inlinestatic

Definition at line 34 of file perlin.c.

Referenced by abs_level_gt1_flag_ts_decode(), abs_level_gtx_flag_decode(), abs_level_gtx_flag_ts_decode(), amvr_precision_idx(), apply_tns(), av_add_stable(), av_fifo_grow2(), build_table(), coeff_abs_level_greater1_flag_decode(), coeff_abs_level_greater2_flag_decode(), coeff_sign_flag_ts_decode(), draw_sono(), evaluate_utility_inc(), ff_aac_apply_tns(), ff_aac_search_for_tns(), ff_hevc_cu_qp_delta_abs(), ff_hevc_hls_residual_coding(), ff_hevc_skip_flag_decode(), ff_hevc_split_coding_unit_flag_decode(), ff_init_hscaler_mmxext(), ff_vvc_alf_ctb_cc_idc(), ff_vvc_alf_ctb_flag(), ff_vvc_cu_skip_flag(), ff_vvc_inter_affine_flag(), ff_vvc_intra_mip_flag(), ff_vvc_lfnst_idx(), ff_vvc_merge_subblock_flag(), ff_vvc_non_inter_flag(), ff_vvc_pred_flag(), ff_vvc_pred_mode_flag(), ff_vvc_pred_mode_ibc_flag(), ff_vvc_regular_merge_flag(), ff_vvc_sbt_flag(), ff_vvc_sbt_horizontal_flag(), ff_vvc_split_cu_flag(), ff_vvc_transform_skip_flag(), ff_vvc_tu_y_coded_flag(), fifo_check_space(), flac_fifo_grow(), get_gtx_flag_inc(), if(), mpegaudio_parse(), mpsub_probe(), mtt_split_cu_binary_flag_decode(), mtt_split_cu_vertical_flag_decode(), par_level_flag_decode(), par_level_flag_ts_decode(), perlin_get(), pnm_parse(), residual_coding_subblock(), sb_coded_flag_decode(), sig_coeff_flag_decode(), significant_coeff_flag_decode(), significant_coeff_group_flag_decode(), split_qt_flag_decode(), svg_probe(), and waves_synth().

grad()

static double grad ( int hash, double x, double y, double z )

inlinestatic

Definition at line 42 of file perlin.c.

Referenced by alf_classify(), alf_classify(), calculate_blockiness(), ff_alf_classify_sum_neon(), and perlin_get().

fade()

static double fade ( double t )

inlinestatic

Definition at line 66 of file perlin.c.

Referenced by perlin_get().

lerp()

static double lerp ( double a, double b, double x )

static

Definition at line 75 of file perlin.c.

Referenced by lerp(), and perlin_get().

ff_perlin_init()

int ff_perlin_init	(	FFPerlin *	perlin,
		double	period,
		int	octaves,
		double	persistence,
		enum FFPerlinRandomMode	random_mode,
		unsigned int	random_seed )

Initialize the Perlin noise generator with parameters.

Parameters

perlin	Perlin noise generator context
period	spatial repeat period, if negative it is ignored
octaves	total number of components making up the noise, each one with doubled frequency
persistence	define ratio used to compute the amplitude of the next octave component with respect to the previous component
random_mode	define how to compute the permutations array
random_seed	when random_mode is set to FF_PERLIN_RANDOM_MODE_RANDOM, set random seed used to compute the permutations array

Returns

a negative AVERROR code in case of error, a non negative value otherwise

Definition at line 101 of file perlin.c.

Referenced by init().

perlin_get()

static double perlin_get ( FFPerlin * perlin, double x, double y, double z )

static

Definition at line 141 of file perlin.c.

Referenced by ff_perlin_get().

ff_perlin_get()

double ff_perlin_get	(	FFPerlin *	perlin,
		double	x,
		double	y,
		double	z )

Compute Perlin noise given the x, y, z coordinates.

Parameters

perlin

Perlin noise generator context

Returns

normalized value for the perlin noise, in the range [0, 1]

Definition at line 208 of file perlin.c.

Referenced by request_frame().

Variable Documentation

ken_permutations

uint8_t ken_permutations[]

static

Initial value:

= {
    151, 160, 137,  91,  90,  15, 131,  13, 201,  95,  96,  53, 194, 233,   7, 225,
    140,  36, 103,  30,  69, 142,   8,  99,  37, 240,  21,  10,  23, 190,   6, 148,
    247, 120, 234,  75,   0,  26, 197,  62,  94, 252, 219, 203, 117,  35,  11,  32,
     57, 177,  33,  88, 237, 149,  56,  87, 174,  20, 125, 136, 171, 168,  68, 175,
     74, 165,  71, 134, 139,  48,  27, 166,  77, 146, 158, 231,  83, 111, 229, 122,
     60, 211, 133, 230, 220, 105,  92,  41,  55,  46, 245,  40, 244, 102, 143,  54,
     65,  25,  63, 161,   1, 216,  80,  73, 209,  76, 132, 187, 208,  89,  18, 169,
    200, 196, 135, 130, 116, 188, 159,  86, 164, 100, 109, 198, 173, 186,   3,  64,
     52, 217, 226, 250, 124, 123,   5, 202,  38, 147, 118, 126, 255,  82,  85, 212,
    207, 206,  59, 227,  47,  16,  58,  17, 182, 189,  28,  42, 223, 183, 170, 213,
    119, 248, 152,   2,  44, 154, 163,  70, 221, 153, 101, 155, 167,  43, 172,   9,
    129,  22,  39, 253,  19,  98, 108, 110,  79, 113, 224, 232, 178, 185, 112, 104,
    218, 246,  97, 228, 251,  34, 242, 193, 238, 210, 144,  12, 191, 179, 162, 241,
     81,  51, 145, 235, 249,  14, 239, 107,  49, 192, 214,  31, 181, 199, 106, 157,
    184,  84, 204, 176, 115, 121,  50,  45, 127,   4, 150, 254, 138, 236, 205,  93,
    222, 114,  67,  29,  24,  72, 243, 141, 128, 195,  78,  66, 215,  61, 156, 180
}

Definition at line 82 of file perlin.c.

Referenced by ff_perlin_init().