--- /dev/null
+// stb_perlin.h - v0.5 - perlin noise
+// public domain single-file C implementation by Sean Barrett
+//
+// LICENSE
+//
+// See end of file.
+//
+//
+// to create the implementation,
+// #define STB_PERLIN_IMPLEMENTATION
+// in *one* C/CPP file that includes this file.
+//
+//
+// Documentation:
+//
+// float stb_perlin_noise3( float x,
+// float y,
+// float z,
+// int x_wrap=0,
+// int y_wrap=0,
+// int z_wrap=0)
+//
+// This function computes a random value at the coordinate (x,y,z).
+// Adjacent random values are continuous but the noise fluctuates
+// its randomness with period 1, i.e. takes on wholly unrelated values
+// at integer points. Specifically, this implements Ken Perlin's
+// revised noise function from 2002.
+//
+// The "wrap" parameters can be used to create wraparound noise that
+// wraps at powers of two. The numbers MUST be powers of two. Specify
+// 0 to mean "don't care". (The noise always wraps every 256 due
+// details of the implementation, even if you ask for larger or no
+// wrapping.)
+//
+// float stb_perlin_noise3_seed( float x,
+// float y,
+// float z,
+// int x_wrap=0,
+// int y_wrap=0,
+// int z_wrap=0,
+// int seed)
+//
+// As above, but 'seed' selects from multiple different variations of the
+// noise function. The current implementation only uses the bottom 8 bits
+// of 'seed', but possibly in the future more bits will be used.
+//
+//
+// Fractal Noise:
+//
+// Three common fractal noise functions are included, which produce
+// a wide variety of nice effects depending on the parameters
+// provided. Note that each function will call stb_perlin_noise3
+// 'octaves' times, so this parameter will affect runtime.
+//
+// float stb_perlin_ridge_noise3(float x, float y, float z,
+// float lacunarity, float gain, float offset, int octaves)
+//
+// float stb_perlin_fbm_noise3(float x, float y, float z,
+// float lacunarity, float gain, int octaves)
+//
+// float stb_perlin_turbulence_noise3(float x, float y, float z,
+// float lacunarity, float gain, int octaves)
+//
+// Typical values to start playing with:
+// octaves = 6 -- number of "octaves" of noise3() to sum
+// lacunarity = ~ 2.0 -- spacing between successive octaves (use exactly 2.0 for wrapping output)
+// gain = 0.5 -- relative weighting applied to each successive octave
+// offset = 1.0? -- used to invert the ridges, may need to be larger, not sure
+//
+//
+// Contributors:
+// Jack Mott - additional noise functions
+// Jordan Peck - seeded noise
+//
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+extern float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap);
+extern float stb_perlin_noise3_seed(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, int seed);
+extern float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves);
+extern float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves);
+extern float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves);
+extern float stb_perlin_noise3_wrap_nonpow2(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed);
+#ifdef __cplusplus
+}
+#endif
+
+#ifdef STB_PERLIN_IMPLEMENTATION
+
+#include <math.h> // fabs()
+
+// not same permutation table as Perlin's reference to avoid copyright issues;
+// Perlin's table can be found at http://mrl.nyu.edu/~perlin/noise/
+static unsigned char stb__perlin_randtab[512] =
+{
+ 23, 125, 161, 52, 103, 117, 70, 37, 247, 101, 203, 169, 124, 126, 44, 123,
+ 152, 238, 145, 45, 171, 114, 253, 10, 192, 136, 4, 157, 249, 30, 35, 72,
+ 175, 63, 77, 90, 181, 16, 96, 111, 133, 104, 75, 162, 93, 56, 66, 240,
+ 8, 50, 84, 229, 49, 210, 173, 239, 141, 1, 87, 18, 2, 198, 143, 57,
+ 225, 160, 58, 217, 168, 206, 245, 204, 199, 6, 73, 60, 20, 230, 211, 233,
+ 94, 200, 88, 9, 74, 155, 33, 15, 219, 130, 226, 202, 83, 236, 42, 172,
+ 165, 218, 55, 222, 46, 107, 98, 154, 109, 67, 196, 178, 127, 158, 13, 243,
+ 65, 79, 166, 248, 25, 224, 115, 80, 68, 51, 184, 128, 232, 208, 151, 122,
+ 26, 212, 105, 43, 179, 213, 235, 148, 146, 89, 14, 195, 28, 78, 112, 76,
+ 250, 47, 24, 251, 140, 108, 186, 190, 228, 170, 183, 139, 39, 188, 244, 246,
+ 132, 48, 119, 144, 180, 138, 134, 193, 82, 182, 120, 121, 86, 220, 209, 3,
+ 91, 241, 149, 85, 205, 150, 113, 216, 31, 100, 41, 164, 177, 214, 153, 231,
+ 38, 71, 185, 174, 97, 201, 29, 95, 7, 92, 54, 254, 191, 118, 34, 221,
+ 131, 11, 163, 99, 234, 81, 227, 147, 156, 176, 17, 142, 69, 12, 110, 62,
+ 27, 255, 0, 194, 59, 116, 242, 252, 19, 21, 187, 53, 207, 129, 64, 135,
+ 61, 40, 167, 237, 102, 223, 106, 159, 197, 189, 215, 137, 36, 32, 22, 5,
+
+ // and a second copy so we don't need an extra mask or static initializer
+ 23, 125, 161, 52, 103, 117, 70, 37, 247, 101, 203, 169, 124, 126, 44, 123,
+ 152, 238, 145, 45, 171, 114, 253, 10, 192, 136, 4, 157, 249, 30, 35, 72,
+ 175, 63, 77, 90, 181, 16, 96, 111, 133, 104, 75, 162, 93, 56, 66, 240,
+ 8, 50, 84, 229, 49, 210, 173, 239, 141, 1, 87, 18, 2, 198, 143, 57,
+ 225, 160, 58, 217, 168, 206, 245, 204, 199, 6, 73, 60, 20, 230, 211, 233,
+ 94, 200, 88, 9, 74, 155, 33, 15, 219, 130, 226, 202, 83, 236, 42, 172,
+ 165, 218, 55, 222, 46, 107, 98, 154, 109, 67, 196, 178, 127, 158, 13, 243,
+ 65, 79, 166, 248, 25, 224, 115, 80, 68, 51, 184, 128, 232, 208, 151, 122,
+ 26, 212, 105, 43, 179, 213, 235, 148, 146, 89, 14, 195, 28, 78, 112, 76,
+ 250, 47, 24, 251, 140, 108, 186, 190, 228, 170, 183, 139, 39, 188, 244, 246,
+ 132, 48, 119, 144, 180, 138, 134, 193, 82, 182, 120, 121, 86, 220, 209, 3,
+ 91, 241, 149, 85, 205, 150, 113, 216, 31, 100, 41, 164, 177, 214, 153, 231,
+ 38, 71, 185, 174, 97, 201, 29, 95, 7, 92, 54, 254, 191, 118, 34, 221,
+ 131, 11, 163, 99, 234, 81, 227, 147, 156, 176, 17, 142, 69, 12, 110, 62,
+ 27, 255, 0, 194, 59, 116, 242, 252, 19, 21, 187, 53, 207, 129, 64, 135,
+ 61, 40, 167, 237, 102, 223, 106, 159, 197, 189, 215, 137, 36, 32, 22, 5,
+};
+
+
+// perlin's gradient has 12 cases so some get used 1/16th of the time
+// and some 2/16ths. We reduce bias by changing those fractions
+// to 5/64ths and 6/64ths
+
+// this array is designed to match the previous implementation
+// of gradient hash: indices[stb__perlin_randtab[i]&63]
+static unsigned char stb__perlin_randtab_grad_idx[512] =
+{
+ 7, 9, 5, 0, 11, 1, 6, 9, 3, 9, 11, 1, 8, 10, 4, 7,
+ 8, 6, 1, 5, 3, 10, 9, 10, 0, 8, 4, 1, 5, 2, 7, 8,
+ 7, 11, 9, 10, 1, 0, 4, 7, 5, 0, 11, 6, 1, 4, 2, 8,
+ 8, 10, 4, 9, 9, 2, 5, 7, 9, 1, 7, 2, 2, 6, 11, 5,
+ 5, 4, 6, 9, 0, 1, 1, 0, 7, 6, 9, 8, 4, 10, 3, 1,
+ 2, 8, 8, 9, 10, 11, 5, 11, 11, 2, 6, 10, 3, 4, 2, 4,
+ 9, 10, 3, 2, 6, 3, 6, 10, 5, 3, 4, 10, 11, 2, 9, 11,
+ 1, 11, 10, 4, 9, 4, 11, 0, 4, 11, 4, 0, 0, 0, 7, 6,
+ 10, 4, 1, 3, 11, 5, 3, 4, 2, 9, 1, 3, 0, 1, 8, 0,
+ 6, 7, 8, 7, 0, 4, 6, 10, 8, 2, 3, 11, 11, 8, 0, 2,
+ 4, 8, 3, 0, 0, 10, 6, 1, 2, 2, 4, 5, 6, 0, 1, 3,
+ 11, 9, 5, 5, 9, 6, 9, 8, 3, 8, 1, 8, 9, 6, 9, 11,
+ 10, 7, 5, 6, 5, 9, 1, 3, 7, 0, 2, 10, 11, 2, 6, 1,
+ 3, 11, 7, 7, 2, 1, 7, 3, 0, 8, 1, 1, 5, 0, 6, 10,
+ 11, 11, 0, 2, 7, 0, 10, 8, 3, 5, 7, 1, 11, 1, 0, 7,
+ 9, 0, 11, 5, 10, 3, 2, 3, 5, 9, 7, 9, 8, 4, 6, 5,
+
+ // and a second copy so we don't need an extra mask or static initializer
+ 7, 9, 5, 0, 11, 1, 6, 9, 3, 9, 11, 1, 8, 10, 4, 7,
+ 8, 6, 1, 5, 3, 10, 9, 10, 0, 8, 4, 1, 5, 2, 7, 8,
+ 7, 11, 9, 10, 1, 0, 4, 7, 5, 0, 11, 6, 1, 4, 2, 8,
+ 8, 10, 4, 9, 9, 2, 5, 7, 9, 1, 7, 2, 2, 6, 11, 5,
+ 5, 4, 6, 9, 0, 1, 1, 0, 7, 6, 9, 8, 4, 10, 3, 1,
+ 2, 8, 8, 9, 10, 11, 5, 11, 11, 2, 6, 10, 3, 4, 2, 4,
+ 9, 10, 3, 2, 6, 3, 6, 10, 5, 3, 4, 10, 11, 2, 9, 11,
+ 1, 11, 10, 4, 9, 4, 11, 0, 4, 11, 4, 0, 0, 0, 7, 6,
+ 10, 4, 1, 3, 11, 5, 3, 4, 2, 9, 1, 3, 0, 1, 8, 0,
+ 6, 7, 8, 7, 0, 4, 6, 10, 8, 2, 3, 11, 11, 8, 0, 2,
+ 4, 8, 3, 0, 0, 10, 6, 1, 2, 2, 4, 5, 6, 0, 1, 3,
+ 11, 9, 5, 5, 9, 6, 9, 8, 3, 8, 1, 8, 9, 6, 9, 11,
+ 10, 7, 5, 6, 5, 9, 1, 3, 7, 0, 2, 10, 11, 2, 6, 1,
+ 3, 11, 7, 7, 2, 1, 7, 3, 0, 8, 1, 1, 5, 0, 6, 10,
+ 11, 11, 0, 2, 7, 0, 10, 8, 3, 5, 7, 1, 11, 1, 0, 7,
+ 9, 0, 11, 5, 10, 3, 2, 3, 5, 9, 7, 9, 8, 4, 6, 5,
+};
+
+static float stb__perlin_lerp(float a, float b, float t)
+{
+ return a + (b-a) * t;
+}
+
+static int stb__perlin_fastfloor(float a)
+{
+ int ai = (int) a;
+ return (a < ai) ? ai-1 : ai;
+}
+
+// different grad function from Perlin's, but easy to modify to match reference
+static float stb__perlin_grad(int grad_idx, float x, float y, float z)
+{
+ static float basis[12][4] =
+ {
+ { 1, 1, 0 },
+ { -1, 1, 0 },
+ { 1,-1, 0 },
+ { -1,-1, 0 },
+ { 1, 0, 1 },
+ { -1, 0, 1 },
+ { 1, 0,-1 },
+ { -1, 0,-1 },
+ { 0, 1, 1 },
+ { 0,-1, 1 },
+ { 0, 1,-1 },
+ { 0,-1,-1 },
+ };
+
+ float *grad = basis[grad_idx];
+ return grad[0]*x + grad[1]*y + grad[2]*z;
+}
+
+float stb_perlin_noise3_internal(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed)
+{
+ float u,v,w;
+ float n000,n001,n010,n011,n100,n101,n110,n111;
+ float n00,n01,n10,n11;
+ float n0,n1;
+
+ unsigned int x_mask = (x_wrap-1) & 255;
+ unsigned int y_mask = (y_wrap-1) & 255;
+ unsigned int z_mask = (z_wrap-1) & 255;
+ int px = stb__perlin_fastfloor(x);
+ int py = stb__perlin_fastfloor(y);
+ int pz = stb__perlin_fastfloor(z);
+ int x0 = px & x_mask, x1 = (px+1) & x_mask;
+ int y0 = py & y_mask, y1 = (py+1) & y_mask;
+ int z0 = pz & z_mask, z1 = (pz+1) & z_mask;
+ int r0,r1, r00,r01,r10,r11;
+
+ #define stb__perlin_ease(a) (((a*6-15)*a + 10) * a * a * a)
+
+ x -= px; u = stb__perlin_ease(x);
+ y -= py; v = stb__perlin_ease(y);
+ z -= pz; w = stb__perlin_ease(z);
+
+ r0 = stb__perlin_randtab[x0+seed];
+ r1 = stb__perlin_randtab[x1+seed];
+
+ r00 = stb__perlin_randtab[r0+y0];
+ r01 = stb__perlin_randtab[r0+y1];
+ r10 = stb__perlin_randtab[r1+y0];
+ r11 = stb__perlin_randtab[r1+y1];
+
+ n000 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z0], x , y , z );
+ n001 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z1], x , y , z-1 );
+ n010 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z0], x , y-1, z );
+ n011 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z1], x , y-1, z-1 );
+ n100 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z0], x-1, y , z );
+ n101 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z1], x-1, y , z-1 );
+ n110 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z0], x-1, y-1, z );
+ n111 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z1], x-1, y-1, z-1 );
+
+ n00 = stb__perlin_lerp(n000,n001,w);
+ n01 = stb__perlin_lerp(n010,n011,w);
+ n10 = stb__perlin_lerp(n100,n101,w);
+ n11 = stb__perlin_lerp(n110,n111,w);
+
+ n0 = stb__perlin_lerp(n00,n01,v);
+ n1 = stb__perlin_lerp(n10,n11,v);
+
+ return stb__perlin_lerp(n0,n1,u);
+}
+
+float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap)
+{
+ return stb_perlin_noise3_internal(x,y,z,x_wrap,y_wrap,z_wrap,0);
+}
+
+float stb_perlin_noise3_seed(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, int seed)
+{
+ return stb_perlin_noise3_internal(x,y,z,x_wrap,y_wrap,z_wrap, (unsigned char) seed);
+}
+
+float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves)
+{
+ int i;
+ float frequency = 1.0f;
+ float prev = 1.0f;
+ float amplitude = 0.5f;
+ float sum = 0.0f;
+
+ for (i = 0; i < octaves; i++) {
+ float r = stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i);
+ r = offset - (float) fabs(r);
+ r = r*r;
+ sum += r*amplitude*prev;
+ prev = r;
+ frequency *= lacunarity;
+ amplitude *= gain;
+ }
+ return sum;
+}
+
+float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves)
+{
+ int i;
+ float frequency = 1.0f;
+ float amplitude = 1.0f;
+ float sum = 0.0f;
+
+ for (i = 0; i < octaves; i++) {
+ sum += stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i)*amplitude;
+ frequency *= lacunarity;
+ amplitude *= gain;
+ }
+ return sum;
+}
+
+float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves)
+{
+ int i;
+ float frequency = 1.0f;
+ float amplitude = 1.0f;
+ float sum = 0.0f;
+
+ for (i = 0; i < octaves; i++) {
+ float r = stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i)*amplitude;
+ sum += (float) fabs(r);
+ frequency *= lacunarity;
+ amplitude *= gain;
+ }
+ return sum;
+}
+
+float stb_perlin_noise3_wrap_nonpow2(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed)
+{
+ float u,v,w;
+ float n000,n001,n010,n011,n100,n101,n110,n111;
+ float n00,n01,n10,n11;
+ float n0,n1;
+
+ int px = stb__perlin_fastfloor(x);
+ int py = stb__perlin_fastfloor(y);
+ int pz = stb__perlin_fastfloor(z);
+ int x_wrap2 = (x_wrap ? x_wrap : 256);
+ int y_wrap2 = (y_wrap ? y_wrap : 256);
+ int z_wrap2 = (z_wrap ? z_wrap : 256);
+ int x0 = px % x_wrap2, x1;
+ int y0 = py % y_wrap2, y1;
+ int z0 = pz % z_wrap2, z1;
+ int r0,r1, r00,r01,r10,r11;
+
+ if (x0 < 0) x0 += x_wrap2;
+ if (y0 < 0) y0 += y_wrap2;
+ if (z0 < 0) z0 += z_wrap2;
+ x1 = (x0+1) % x_wrap2;
+ y1 = (y0+1) % y_wrap2;
+ z1 = (z0+1) % z_wrap2;
+
+ #define stb__perlin_ease(a) (((a*6-15)*a + 10) * a * a * a)
+
+ x -= px; u = stb__perlin_ease(x);
+ y -= py; v = stb__perlin_ease(y);
+ z -= pz; w = stb__perlin_ease(z);
+
+ r0 = stb__perlin_randtab[x0];
+ r0 = stb__perlin_randtab[r0+seed];
+ r1 = stb__perlin_randtab[x1];
+ r1 = stb__perlin_randtab[r1+seed];
+
+ r00 = stb__perlin_randtab[r0+y0];
+ r01 = stb__perlin_randtab[r0+y1];
+ r10 = stb__perlin_randtab[r1+y0];
+ r11 = stb__perlin_randtab[r1+y1];
+
+ n000 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z0], x , y , z );
+ n001 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z1], x , y , z-1 );
+ n010 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z0], x , y-1, z );
+ n011 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z1], x , y-1, z-1 );
+ n100 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z0], x-1, y , z );
+ n101 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z1], x-1, y , z-1 );
+ n110 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z0], x-1, y-1, z );
+ n111 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z1], x-1, y-1, z-1 );
+
+ n00 = stb__perlin_lerp(n000,n001,w);
+ n01 = stb__perlin_lerp(n010,n011,w);
+ n10 = stb__perlin_lerp(n100,n101,w);
+ n11 = stb__perlin_lerp(n110,n111,w);
+
+ n0 = stb__perlin_lerp(n00,n01,v);
+ n1 = stb__perlin_lerp(n10,n11,v);
+
+ return stb__perlin_lerp(n0,n1,u);
+}
+#endif // STB_PERLIN_IMPLEMENTATION
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
+software, either in source code form or as a compiled binary, for any purpose,
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and to
+the detriment of our heirs and successors. We intend this dedication to be an
+overt act of relinquishment in perpetuity of all present and future rights to
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/
projects / pistorm / blobdiff