591 lines
16 KiB
C
591 lines
16 KiB
C
#include <SST/SST_SimplexNoise.h>
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#include <time.h>
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#include <math.h>
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#include <stdlib.h>
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#include <pstdint.h>
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#include <string.h> /* memcpy() */
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static const int grad3[][3] =
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{
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{1,1,0}, {-1,1,0}, {1,-1,0}, {-1,-1,0},
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{1,0,1}, {-1,0,1}, {1,0,-1}, {-1,0,-1},
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{0,1,1}, {0,-1,1}, {0,1,-1}, {0,-1,-1}
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};
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static const int grad4[][4] =
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{
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{0,1,1,1}, {0,1,1,-1}, {0,1,-1,1}, {0,1,-1,-1},
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{0,-1,1,1}, {0,-1,1,-1}, {0,-1,-1,1}, {0,-1,-1,-1},
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{1,0,1,1}, {1,0,1,-1}, {1,0,-1,1}, {1,0,-1,-1},
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{-1,0,1,1}, {-1,0,1,-1}, {-1,0,-1,1}, {-1,0,-1,-1},
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{1,1,0,1}, {1,1,0,-1}, {1,-1,0,1}, {1,-1,0,-1},
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{-1,1,0,1}, {-1,1,0,-1}, {-1,-1,0,1}, {-1,-1,0,-1},
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{1,1,1,0}, {1,1,-1,0}, {1,-1,1,0}, {1,-1,-1,0},
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{-1,1,1,0}, {-1,1,-1,0}, {-1,-1,1,0}, {-1,-1,-1,0}
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};
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static const int p[] =
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{
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151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,
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225,140,36,103,30,69,142,8,99,37,240,21,10,23,190,6,
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148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,
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11,32,57,177,33,88,237,149,56,87,174,20,125,136,171,
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168, 68,175,74,165,71,134,139,48,27,166,77,146,158,
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231,83,111,229,122,60,211,133,230,220,105,92,41,55,
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46,245,40,244,102,143,54,65,25,63,161,1,216,80,73,
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209,76,132,187,208, 89,18,169,200,196,135,130,116,188,
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159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,
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123,5,202,38,147,118,126,255,82,85,212,207,206,59,227,
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47,16,58,17,182,189,28,42,223,183,170,213,119,248,152,
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2,44,154,163, 70,221,153,101,155,167, 43,172,9,129,22,
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39,253, 19,98,108,110,79,113,224,232,178,185,112,104,
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218,246,97,228,251,34,242,193,238,210,144,12,191,179,
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162,241, 81,51,145,235,249,14,239,107,49,192,214,31,
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181,199,106,157,184,84,204,176,115,121,50,45,127,4,150,
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254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,
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78,66,215,61,156,180
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};
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/*
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A lookup table to traverse the simplex around a given point in 4D.
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Details can be found where this table is used, in the 4D noise method.
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*/
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static const int simplex[][4] =
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{
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{0,1,2,3},{0,1,3,2},{0,0,0,0},{0,2,3,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,2,3,0},
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{0,2,1,3},{0,0,0,0},{0,3,1,2},{0,3,2,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,3,2,0},
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{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
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{1,2,0,3},{0,0,0,0},{1,3,0,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,3,0,1},{2,3,1,0},
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{1,0,2,3},{1,0,3,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,0,3,1},{0,0,0,0},{2,1,3,0},
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{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
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{2,0,1,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,0,1,2},{3,0,2,1},{0,0,0,0},{3,1,2,0},
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{2,1,0,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,1,0,2},{0,0,0,0},{3,2,0,1},{3,2,1,0}
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};
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typedef struct
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{
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int perm[512];
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} SST_Simplex_Data_t;
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static int fastfloor(const double x)
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{
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return (int) floor(x);
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}
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static double dot2(const int* g, const double x, const double y)
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{
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return g[0]*x + g[1]*y;
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}
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static double dot3(const int* g, const double x, const double y, const double z)
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{
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return g[0]*x + g[1]*y + g[2]*z;
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}
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static double dot4(const int* g, const double x, const double y, const double z, const double w)
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{
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return g[0]*x + g[1]*y + g[2]*z + g[3]*w;
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}
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SST_SimplexNoise SST_Random_CreateSimplexNoise()
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{
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return SST_Random_CreateSimplexNoiseFromSeed((uint32_t) time(NULL));
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}
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SST_SimplexNoise SST_Random_CreateSimplexNoiseFromSeed(uint32_t _seed)
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{
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SST_Simplex_Data_t* ret = (SST_Simplex_Data_t *)calloc(sizeof(SST_Simplex_Data_t), 1);
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size_t i;
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if (ret == NULL)
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return NULL;
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for(i = 0; i < 512; i++)
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ret->perm[i] = p[i & 255];
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SST_Random_ReseedSimplexNoise(ret, _seed);
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return (SST_SimplexNoise) ret;
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}
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void SST_Random_ReseedSimplexNoise(SST_SimplexNoise _source, uint32_t _seed)
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{
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SST_Simplex_Data_t* temp = (SST_Simplex_Data_t *) _source;
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int i;
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/* reseeding here currently means shifting around the values */
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for(i = 0; i < 512; i++)
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temp->perm[i] = p[ ( (i + _seed) % 256) & 255];
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}
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SST_SimplexNoise SST_Random_CloneSimplexNoise(SST_SimplexNoise _source)
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{
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SST_Simplex_Data_t* ret;
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if (_source == NULL)
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return NULL;
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ret = (SST_Simplex_Data_t*)calloc(sizeof(SST_Simplex_Data_t), 1);
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memcpy(ret,(SST_Simplex_Data_t*)_source, sizeof(SST_Simplex_Data_t));
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return (SST_SimplexNoise) ret;
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}
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void SST_Random_DestroySimplexNoise(SST_SimplexNoise _instance)
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{
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free(_instance);
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}
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float SST_Random_MapSimplexNoise1D( SST_SimplexNoise _instance, float _x)
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{
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/* HACKHACK */
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return SST_Random_MapSimplexNoise2D(_instance,_x,0);
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}
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void SST_Random_MapSimplexNoise1DFromArray( SST_SimplexNoise _instance, float* _destination, float* _sourceX, size_t _numElements)
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{
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size_t i;
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if (_destination == NULL || _sourceX == NULL)
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return;
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for (i = 0; i < _numElements; i++)
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_destination[i] = SST_Random_MapSimplexNoise1D(_instance, _sourceX[i]);
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}
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float SST_Random_MapSimplexNoise2D( SST_SimplexNoise _instance, float _x, float _y)
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{
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int* perm;
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int i, j;
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int i1, j1; /* Offsets for second (middle) corner of simplex in (i,j) coords */
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double n0, n1, n2; /* Noise contributions from the three corners */
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double s, t,x0,X0,y0,Y0;
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double x1,y1,x2,y2;
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double t0,t1,t2;
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int ii, jj, gi0, gi1, gi2;
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/* Skew the input space to determine which simplex cell we're in */
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const double F2 = 0.5*(sqrtf(3.0)-1.0);
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const double G2 = (3.0-sqrtf(3.0))/6.0;
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s = (_x+_y)*F2; // Hairy factor for 2D
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i = fastfloor(_x+s);
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j = fastfloor(_y+s);
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t = (i+j)*G2;
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X0 = i-t; /* Unskew the cell origin back to (x,y) space */
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Y0 = j-t;
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x0 = _x-X0; /* The x,y distances from the cell origin */
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y0 = _y-Y0;
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/*
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For the 2D case, the simplex shape is an equilateral triangle.
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Determine which simplex we are in.
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*/
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perm = ((SST_Simplex_Data_t*)_instance)->perm;
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if(x0>y0)
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{
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i1=1;
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j1=0;
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} /* lower triangle, XY order: (0,0)->(1,0)->(1,1) */
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else
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{
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i1=0;
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j1=1;
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} /* upper triangle, YX order: (0,0)->(0,1)->(1,1) */
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/*
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A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
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a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
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c = (3-sqrt(3))/6
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*/
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x1 = x0 - i1 + G2; /* Offsets for middle corner in (x,y) unskewed coords */
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y1 = y0 - j1 + G2;
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x2 = x0 - 1.0 + 2.0 * G2; /* Offsets for last corner in (x,y) unskewed coords */
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y2 = y0 - 1.0 + 2.0 * G2;
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/* Work out the hashed gradient indices of the three simplex corners */
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ii = i & 255;
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jj = j & 255;
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gi0 = perm[ii+perm[jj]] % 12;
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gi1 = perm[ii+i1+perm[jj+j1]] % 12;
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gi2 = perm[ii+1+perm[jj+1]] % 12;
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/* Calculate the contribution from the three corners */
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t0 = 0.5 - x0*x0-y0*y0;
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if(t0<0)
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n0 = 0.0;
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else
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{
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t0 *= t0;
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n0 = t0 * t0 * dot2(grad3[gi0], x0, y0); /* (x,y) of grad3 used for 2D gradient */
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}
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t1 = 0.5 - x1*x1-y1*y1;
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if(t1<0)
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n1 = 0.0;
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else
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{
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t1 *= t1;
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n1 = t1 * t1 * dot2(grad3[gi1], x1, y1);
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}
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t2 = 0.5 - x2*x2-y2*y2;
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if (t2<0)
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n2 = 0.0;
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else
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{
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t2 *= t2;
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n2 = t2 * t2 * dot2(grad3[gi2], x2, y2);
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}
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/*
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Add contributions from each corner to get the final noise value.
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The result is scaled to return values in the interval [-1,1].
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TODO check accuracy of this
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*/
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return (float) (70.0 * (n0 + n1 + n2));
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}
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void SST_Random_MapSimplexNoise2DFromArray( SST_SimplexNoise _instance, float* _destination, float* _sourceX, float* _sourceY, size_t _numElements)
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{
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size_t i;
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if (_destination == NULL || _sourceX == NULL || _sourceY == NULL)
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return;
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for (i = 0; i < _numElements; i++)
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_destination[i] = SST_Random_MapSimplexNoise2D(_instance, _sourceX[i], _sourceY[i]);
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}
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float SST_Random_MapSimplexNoise3D( SST_SimplexNoise _instance, float _x, float _y, float _z)
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{
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double n0, n1, n2, n3; /* Noise contributions from the four corners */
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/* Skew the input space to determine which simplex cell we're in */
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const double F3 = 1.0/3.0;
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const double G3 = 1.0/6.0; /* Very nice and simple unskew factor, too */
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double s = (_x+_y+_z)*F3; /* Very nice and simple skew factor for 3D */
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int i = (int)floor(_x+s);
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int j = (int)floor(_y+s);
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int k = (int)floor(_z+s);
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double t = (i+j+k)*G3;
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double X0 = i-t; /* Unskew the cell origin back to (x,y,z) space */
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double Y0 = j-t;
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double Z0 = k-t;
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double x0 = _x-X0; /* The x,y,z distances from the cell origin */
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double y0 = _y-Y0;
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double z0 = _z-Z0;
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double x1,y1,z1,x2,y2,z2,x3,y3,z3;
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double t0,t1,t2,t3;
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/*
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For the 3D case, the simplex shape is a slightly irregular tetrahedron.
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Determine which simplex we are in.
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*/
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int i1, j1, k1; /* Offsets for second corner of simplex in (i,j,k) coords */
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int i2, j2, k2; /* Offsets for third corner of simplex in (i,j,k) coords */
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int ii,jj,kk,gi0,gi1,gi2,gi3;
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int* perm = ((SST_Simplex_Data_t*)_instance)->perm;
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if(x0>=y0)
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{
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if(y0>=z0)
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{
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i1=1;
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j1=0;
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k1=0;
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i2=1;
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j2=1;
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k2=0;
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} /* X Y Z order */
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else if(x0>=z0)
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{
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i1=1;
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j1=0;
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k1=0;
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i2=1;
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j2=0;
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k2=1;
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} /* X Z Y order */
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else
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{
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i1=0;
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j1=0;
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k1=1;
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i2=1;
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j2=0;
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k2=1;
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} /* Z X Y order */
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}
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else
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{ /* x0<y0 */
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if(y0<z0)
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{
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i1=0;
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j1=0;
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k1=1;
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i2=0;
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j2=1;
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k2=1;
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} /* Z Y X order */
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else if(x0<z0)
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{
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i1=0;
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j1=1;
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k1=0;
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i2=0;
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j2=1;
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k2=1;
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} /* Y Z X order */
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else
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{
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i1=0;
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j1=1;
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k1=0;
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i2=1;
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j2=1;
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k2=0;
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} /* Y X Z order */
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}
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/*
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A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
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a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
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a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
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c = 1/6
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*/
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x1 = x0 - i1 + G3; /* Offsets for second corner in (x,y,z) coords */
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y1 = y0 - j1 + G3;
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z1 = z0 - k1 + G3;
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x2 = x0 - i2 + 2.0*G3; /* Offsets for third corner in (x,y,z) coords */
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y2 = y0 - j2 + 2.0*G3;
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z2 = z0 - k2 + 2.0*G3;
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x3 = x0 - 1.0 + 3.0*G3; /* Offsets for last corner in (x,y,z) coords */
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y3 = y0 - 1.0 + 3.0*G3;
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z3 = z0 - 1.0 + 3.0*G3;
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/* Work out the hashed gradient indices of the four simplex corners */
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ii = i & 255;
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jj = j & 255;
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kk = k & 255;
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gi0 = perm[ii+perm[jj+perm[kk]]] % 12;
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gi1 = perm[ii+i1+perm[jj+j1+perm[kk+k1]]] % 12;
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gi2 = perm[ii+i2+perm[jj+j2+perm[kk+k2]]] % 12;
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gi3 = perm[ii+1+perm[jj+1+perm[kk+1]]] % 12;
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/* Calculate the contribution from the four corners */
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t0 = 0.6 - x0*x0 - y0*y0 - z0*z0;
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if(t0<0)
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n0 = 0.0;
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else
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{
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t0 *= t0;
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n0 = t0 * t0 * dot3(grad3[gi0], x0, y0, z0);
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}
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t1 = 0.6 - x1*x1 - y1*y1 - z1*z1;
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if(t1<0) n1 = 0.0;
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else
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{
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t1 *= t1;
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n1 = t1 * t1 * dot3(grad3[gi1], x1, y1, z1);
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}
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t2 = 0.6 - x2*x2 - y2*y2 - z2*z2;
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if(t2<0)
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n2 = 0.0;
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else
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{
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t2 *= t2;
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n2 = t2 * t2 * dot3(grad3[gi2], x2, y2, z2);
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}
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t3 = 0.6 - x3*x3 - y3*y3 - z3*z3;
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if(t3<0)
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n3 = 0.0;
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else
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{
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t3 *= t3;
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n3 = t3 * t3 * dot3(grad3[gi3], x3, y3, z3);
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}
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/*
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Add contributions from each corner to get the final noise value.
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The result is scaled to stay just inside [-1,1]
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*/
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return (float)(32.0*(n0 + n1 + n2 + n3));
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}
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void SST_Random_MapSimplexNoise3DFromArray( SST_SimplexNoise _instance, float* _destination, float* _sourceX, float* _sourceY, float* _sourceZ, size_t _numElements)
|
||
{
|
||
size_t i;
|
||
|
||
if (_destination == NULL || _sourceX == NULL || _sourceY == NULL || _sourceZ == NULL)
|
||
return;
|
||
|
||
for (i = 0; i < _numElements; i++)
|
||
_destination[i] = SST_Random_MapSimplexNoise3D(_instance, _sourceX[i], _sourceY[i], _sourceZ[i]);
|
||
}
|
||
|
||
float SST_Random_MapSimplexNoise4D( SST_SimplexNoise _instance, float _x, float _y, float _z, float _w)
|
||
{
|
||
/* The skewing and unskewing factors are hairy again for the 4D case */
|
||
const double F4 = (sqrtf(5.0)-1.0)/4.0;
|
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const double G4 = (5.0-sqrtf(5.0))/20.0;
|
||
double n0, n1, n2, n3, n4; /* Noise contributions from the five corners */
|
||
|
||
/* Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in */
|
||
double s = (_x + _y + _z + _w) * F4; /* Factor for 4D skewing */
|
||
int i = fastfloor(_x + s);
|
||
int j = fastfloor(_y + s);
|
||
int k = fastfloor(_z + s);
|
||
int l = fastfloor(_w + s);
|
||
double t = (i + j + k + l) * G4; /* Factor for 4D unskewing */
|
||
double X0 = i - t; /* Unskew the cell origin back to (x,y,z,w) space */
|
||
double Y0 = j - t;
|
||
double Z0 = k - t;
|
||
double W0 = l - t;
|
||
double x0,x1,x2,x3,x4,y0,y1,y2,y3,y4,z0,z1,z2,z3,z4,w0,w1,w2,w3,w4;
|
||
int c,c1,c2,c3,c4,c5,c6;
|
||
double t0,t1,t2,t3,t4;
|
||
int i1, j1, k1, l1; /* The integer offsets for the second simplex corner */
|
||
int i2, j2, k2, l2; /* The integer offsets for the third simplex corner */
|
||
int i3, j3, k3, l3; /* The integer offsets for the fourth simplex corner */
|
||
int ii,jj,kk,ll,gi0,gi1,gi2,gi3,gi4;
|
||
int* perm = ((SST_Simplex_Data_t*)_instance)->perm;
|
||
|
||
x0 = _x - X0; /* The x,y,z,w distances from the cell origin */
|
||
y0 = _y - Y0;
|
||
z0 = _z - Z0;
|
||
w0 = _w - W0;
|
||
|
||
/*
|
||
For the 4D case, the simplex is a 4D shape I won't even try to describe.
|
||
To find out which of the 24 possible simplices we're in, we need to
|
||
determine the magnitude ordering of x0, y0, z0 and w0.
|
||
The method below is a good way of finding the ordering of x,y,z,w and
|
||
then find the correct traversal order for the simplex we<77>re in.
|
||
First, six pair-wise comparisons are performed between each possible pair
|
||
of the four coordinates, and the results are used to add up binary bits
|
||
for an integer index.
|
||
*/
|
||
c1 = (x0 > y0) ? 32 : 0;
|
||
c2 = (x0 > z0) ? 16 : 0;
|
||
c3 = (y0 > z0) ? 8 : 0;
|
||
c4 = (x0 > w0) ? 4 : 0;
|
||
c5 = (y0 > w0) ? 2 : 0;
|
||
c6 = (z0 > w0) ? 1 : 0;
|
||
c = c1 + c2 + c3 + c4 + c5 + c6;
|
||
|
||
/*
|
||
simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order.
|
||
Many values of c will never occur, since e.g. x>y>z>w makes x<z, y<w and x<w
|
||
impossible. Only the 24 indices which have non-zero entries make any sense.
|
||
We use a thresholding to set the coordinates in turn from the largest magnitude.
|
||
The number 3 in the "simplex" array is at the position of the largest coordinate.
|
||
*/
|
||
i1 = simplex[c][0]>=3 ? 1 : 0;
|
||
j1 = simplex[c][1]>=3 ? 1 : 0;
|
||
k1 = simplex[c][2]>=3 ? 1 : 0;
|
||
l1 = simplex[c][3]>=3 ? 1 : 0;
|
||
|
||
/* The number 2 in the "simplex" array is at the second largest coordinate. */
|
||
i2 = simplex[c][0]>=2 ? 1 : 0;
|
||
j2 = simplex[c][1]>=2 ? 1 : 0;
|
||
k2 = simplex[c][2]>=2 ? 1 : 0;
|
||
l2 = simplex[c][3]>=2 ? 1 : 0;
|
||
|
||
/* The number 1 in the "simplex" array is at the second smallest coordinate. */
|
||
i3 = simplex[c][0]>=1 ? 1 : 0;
|
||
j3 = simplex[c][1]>=1 ? 1 : 0;
|
||
k3 = simplex[c][2]>=1 ? 1 : 0;
|
||
l3 = simplex[c][3]>=1 ? 1 : 0;
|
||
|
||
/* The fifth corner has all coordinate offsets = 1, so no need to look that up. */
|
||
x1 = x0 - i1 + G4; /* Offsets for second corner in (x,y,z,w) coords */
|
||
y1 = y0 - j1 + G4;
|
||
z1 = z0 - k1 + G4;
|
||
w1 = w0 - l1 + G4;
|
||
x2 = x0 - i2 + 2.0*G4; /* Offsets for third corner in (x,y,z,w) coords */
|
||
y2 = y0 - j2 + 2.0*G4;
|
||
z2 = z0 - k2 + 2.0*G4;
|
||
w2 = w0 - l2 + 2.0*G4;
|
||
x3 = x0 - i3 + 3.0*G4; /* Offsets for fourth corner in (x,y,z,w) coords */
|
||
y3 = y0 - j3 + 3.0*G4;
|
||
z3 = z0 - k3 + 3.0*G4;
|
||
w3 = w0 - l3 + 3.0*G4;
|
||
x4 = x0 - 1.0 + 4.0*G4; /* Offsets for last corner in (x,y,z,w) coords */
|
||
y4 = y0 - 1.0 + 4.0*G4;
|
||
z4 = z0 - 1.0 + 4.0*G4;
|
||
w4 = w0 - 1.0 + 4.0*G4;
|
||
|
||
/* Work out the hashed gradient indices of the five simplex corners */
|
||
ii = i & 255;
|
||
jj = j & 255;
|
||
kk = k & 255;
|
||
ll = l & 255;
|
||
gi0 = perm[ii+perm[jj+perm[kk+perm[ll]]]] % 32;
|
||
gi1 = perm[ii+i1+perm[jj+j1+perm[kk+k1+perm[ll+l1]]]] % 32;
|
||
gi2 = perm[ii+i2+perm[jj+j2+perm[kk+k2+perm[ll+l2]]]] % 32;
|
||
gi3 = perm[ii+i3+perm[jj+j3+perm[kk+k3+perm[ll+l3]]]] % 32;
|
||
gi4 = perm[ii+1+perm[jj+1+perm[kk+1+perm[ll+1]]]] % 32;
|
||
|
||
/* Calculate the contribution from the five corners */
|
||
t0 = 0.6 - x0*x0 - y0*y0 - z0*z0 - w0*w0;
|
||
if(t0<0)
|
||
n0 = 0.0;
|
||
else
|
||
{
|
||
t0 *= t0;
|
||
n0 = t0 * t0 * dot4(grad4[gi0], x0, y0, z0, w0);
|
||
}
|
||
t1 = 0.6 - x1*x1 - y1*y1 - z1*z1 - w1*w1;
|
||
if(t1<0)
|
||
n1 = 0.0;
|
||
else
|
||
{
|
||
t1 *= t1;
|
||
n1 = t1 * t1 * dot4(grad4[gi1], x1, y1, z1, w1);
|
||
}
|
||
t2 = 0.6 - x2*x2 - y2*y2 - z2*z2 - w2*w2;
|
||
if(t2<0)
|
||
n2 = 0.0;
|
||
else
|
||
{
|
||
t2 *= t2;
|
||
n2 = t2 * t2 * dot4(grad4[gi2], x2, y2, z2, w2);
|
||
}
|
||
|
||
t3 = 0.6 - x3*x3 - y3*y3 - z3*z3 - w3*w3;
|
||
|
||
if(t3<0)
|
||
n3 = 0.0;
|
||
else
|
||
{
|
||
t3 *= t3;
|
||
n3 = t3 * t3 * dot4(grad4[gi3], x3, y3, z3, w3);
|
||
}
|
||
t4 = 0.6 - x4*x4 - y4*y4 - z4*z4 - w4*w4;
|
||
if(t4<0)
|
||
n4 = 0.0;
|
||
else
|
||
{
|
||
t4 *= t4;
|
||
n4 = t4 * t4 * dot4(grad4[gi4], x4, y4, z4, w4);
|
||
}
|
||
|
||
/* Sum up and scale the result to cover the range [-1,1] */
|
||
return (float)(27.0 * (n0 + n1 + n2 + n3 + n4));
|
||
}
|
||
|
||
void SST_Random_MapSimplexNoise4DFromArray( SST_SimplexNoise _instance, float* _destination, float* _sourceX, float* _sourceY, float* _sourceZ, float* _sourceW, size_t _numElements)
|
||
{
|
||
size_t i;
|
||
|
||
if (_destination == NULL || _sourceX == NULL || _sourceY == NULL || _sourceZ == NULL || _sourceW == NULL)
|
||
return;
|
||
|
||
for (i = 0; i < _numElements; i++)
|
||
_destination[i] = SST_Random_MapSimplexNoise4D(_instance, _sourceX[i], _sourceY[i], _sourceZ[i], _sourceW[i]);
|
||
}
|