1// stb_perlin.h - v0.3 - perlin noise
2// public domain single-file C implementation by Sean Barrett
3//
4// LICENSE
5//
6// See end of file.
7//
8//
9// to create the implementation,
10// #define STB_PERLIN_IMPLEMENTATION
11// in *one* C/CPP file that includes this file.
12//
13//
14// Documentation:
15//
16// float stb_perlin_noise3( float x,
17// float y,
18// float z,
19// int x_wrap=0,
20// int y_wrap=0,
21// int z_wrap=0)
22//
23// This function computes a random value at the coordinate (x,y,z).
24// Adjacent random values are continuous but the noise fluctuates
25// its randomness with period 1, i.e. takes on wholly unrelated values
26// at integer points. Specifically, this implements Ken Perlin's
27// revised noise function from 2002.
28//
29// The "wrap" parameters can be used to create wraparound noise that
30// wraps at powers of two. The numbers MUST be powers of two. Specify
31// 0 to mean "don't care". (The noise always wraps every 256 due
32// details of the implementation, even if you ask for larger or no
33// wrapping.)
34//
35// Fractal Noise:
36//
37// Three common fractal noise functions are included, which produce
38// a wide variety of nice effects depending on the parameters
39// provided. Note that each function will call stb_perlin_noise3
40// 'octaves' times, so this parameter will affect runtime.
41//
42// float stb_perlin_ridge_noise3(float x, float y, float z,
43// float lacunarity, float gain, float offset, int octaves,
44// int x_wrap, int y_wrap, int z_wrap);
45//
46// float stb_perlin_fbm_noise3(float x, float y, float z,
47// float lacunarity, float gain, int octaves,
48// int x_wrap, int y_wrap, int z_wrap);
49//
50// float stb_perlin_turbulence_noise3(float x, float y, float z,
51// float lacunarity, float gain,int octaves,
52// int x_wrap, int y_wrap, int z_wrap);
53//
54// Typical values to start playing with:
55// octaves = 6 -- number of "octaves" of noise3() to sum
56// lacunarity = ~ 2.0 -- spacing between successive octaves (use exactly 2.0 for wrapping output)
57// gain = 0.5 -- relative weighting applied to each successive octave
58// offset = 1.0? -- used to invert the ridges, may need to be larger, not sure
59//
60//
61// Contributors:
62// Jack Mott - additional noise functions
63//
64
65
66#ifdef __cplusplus
67extern "C" {
68#endif
69extern float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap);
70extern float stb_perlin_ridge_noise3(float x, float y, float z,float lacunarity, float gain, float offset, int octaves,int x_wrap, int y_wrap, int z_wrap);
71extern float stb_perlin_fbm_noise3(float x, float y, float z,float lacunarity, float gain, int octaves,int x_wrap, int y_wrap, int z_wrap);
72extern float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves,int x_wrap, int y_wrap, int z_wrap);
73#ifdef __cplusplus
74}
75#endif
76
77#ifdef STB_PERLIN_IMPLEMENTATION
78
79// not same permutation table as Perlin's reference to avoid copyright issues;
80// Perlin's table can be found at http://mrl.nyu.edu/~perlin/noise/
81// @OPTIMIZE: should this be unsigned char instead of int for cache?
82static unsigned char stb__perlin_randtab[512] =
83{
84 23, 125, 161, 52, 103, 117, 70, 37, 247, 101, 203, 169, 124, 126, 44, 123,
85 152, 238, 145, 45, 171, 114, 253, 10, 192, 136, 4, 157, 249, 30, 35, 72,
86 175, 63, 77, 90, 181, 16, 96, 111, 133, 104, 75, 162, 93, 56, 66, 240,
87 8, 50, 84, 229, 49, 210, 173, 239, 141, 1, 87, 18, 2, 198, 143, 57,
88 225, 160, 58, 217, 168, 206, 245, 204, 199, 6, 73, 60, 20, 230, 211, 233,
89 94, 200, 88, 9, 74, 155, 33, 15, 219, 130, 226, 202, 83, 236, 42, 172,
90 165, 218, 55, 222, 46, 107, 98, 154, 109, 67, 196, 178, 127, 158, 13, 243,
91 65, 79, 166, 248, 25, 224, 115, 80, 68, 51, 184, 128, 232, 208, 151, 122,
92 26, 212, 105, 43, 179, 213, 235, 148, 146, 89, 14, 195, 28, 78, 112, 76,
93 250, 47, 24, 251, 140, 108, 186, 190, 228, 170, 183, 139, 39, 188, 244, 246,
94 132, 48, 119, 144, 180, 138, 134, 193, 82, 182, 120, 121, 86, 220, 209, 3,
95 91, 241, 149, 85, 205, 150, 113, 216, 31, 100, 41, 164, 177, 214, 153, 231,
96 38, 71, 185, 174, 97, 201, 29, 95, 7, 92, 54, 254, 191, 118, 34, 221,
97 131, 11, 163, 99, 234, 81, 227, 147, 156, 176, 17, 142, 69, 12, 110, 62,
98 27, 255, 0, 194, 59, 116, 242, 252, 19, 21, 187, 53, 207, 129, 64, 135,
99 61, 40, 167, 237, 102, 223, 106, 159, 197, 189, 215, 137, 36, 32, 22, 5,
100
101 // and a second copy so we don't need an extra mask or static initializer
102 23, 125, 161, 52, 103, 117, 70, 37, 247, 101, 203, 169, 124, 126, 44, 123,
103 152, 238, 145, 45, 171, 114, 253, 10, 192, 136, 4, 157, 249, 30, 35, 72,
104 175, 63, 77, 90, 181, 16, 96, 111, 133, 104, 75, 162, 93, 56, 66, 240,
105 8, 50, 84, 229, 49, 210, 173, 239, 141, 1, 87, 18, 2, 198, 143, 57,
106 225, 160, 58, 217, 168, 206, 245, 204, 199, 6, 73, 60, 20, 230, 211, 233,
107 94, 200, 88, 9, 74, 155, 33, 15, 219, 130, 226, 202, 83, 236, 42, 172,
108 165, 218, 55, 222, 46, 107, 98, 154, 109, 67, 196, 178, 127, 158, 13, 243,
109 65, 79, 166, 248, 25, 224, 115, 80, 68, 51, 184, 128, 232, 208, 151, 122,
110 26, 212, 105, 43, 179, 213, 235, 148, 146, 89, 14, 195, 28, 78, 112, 76,
111 250, 47, 24, 251, 140, 108, 186, 190, 228, 170, 183, 139, 39, 188, 244, 246,
112 132, 48, 119, 144, 180, 138, 134, 193, 82, 182, 120, 121, 86, 220, 209, 3,
113 91, 241, 149, 85, 205, 150, 113, 216, 31, 100, 41, 164, 177, 214, 153, 231,
114 38, 71, 185, 174, 97, 201, 29, 95, 7, 92, 54, 254, 191, 118, 34, 221,
115 131, 11, 163, 99, 234, 81, 227, 147, 156, 176, 17, 142, 69, 12, 110, 62,
116 27, 255, 0, 194, 59, 116, 242, 252, 19, 21, 187, 53, 207, 129, 64, 135,
117 61, 40, 167, 237, 102, 223, 106, 159, 197, 189, 215, 137, 36, 32, 22, 5,
118};
119
120static float stb__perlin_lerp(float a, float b, float t)
121{
122 return a + (b-a) * t;
123}
124
125static int stb__perlin_fastfloor(float a)
126{
127 int ai = (int) a;
128 return (a < ai) ? ai-1 : ai;
129}
130
131// different grad function from Perlin's, but easy to modify to match reference
132static float stb__perlin_grad(int hash, float x, float y, float z)
133{
134 static float basis[12][4] =
135 {
136 { 1, 1, 0 },
137 { -1, 1, 0 },
138 { 1,-1, 0 },
139 { -1,-1, 0 },
140 { 1, 0, 1 },
141 { -1, 0, 1 },
142 { 1, 0,-1 },
143 { -1, 0,-1 },
144 { 0, 1, 1 },
145 { 0,-1, 1 },
146 { 0, 1,-1 },
147 { 0,-1,-1 },
148 };
149
150 // perlin's gradient has 12 cases so some get used 1/16th of the time
151 // and some 2/16ths. We reduce bias by changing those fractions
152 // to 5/64ths and 6/64ths, and the same 4 cases get the extra weight.
153 static unsigned char indices[64] =
154 {
155 0,1,2,3,4,5,6,7,8,9,10,11,
156 0,9,1,11,
157 0,1,2,3,4,5,6,7,8,9,10,11,
158 0,1,2,3,4,5,6,7,8,9,10,11,
159 0,1,2,3,4,5,6,7,8,9,10,11,
160 0,1,2,3,4,5,6,7,8,9,10,11,
161 };
162
163 // if you use reference permutation table, change 63 below to 15 to match reference
164 // (this is why the ordering of the table above is funky)
165 float *grad = basis[indices[hash & 63]];
166 return grad[0]*x + grad[1]*y + grad[2]*z;
167}
168
169float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap)
170{
171 float u,v,w;
172 float n000,n001,n010,n011,n100,n101,n110,n111;
173 float n00,n01,n10,n11;
174 float n0,n1;
175
176 unsigned int x_mask = (x_wrap-1) & 255;
177 unsigned int y_mask = (y_wrap-1) & 255;
178 unsigned int z_mask = (z_wrap-1) & 255;
179 int px = stb__perlin_fastfloor(x);
180 int py = stb__perlin_fastfloor(y);
181 int pz = stb__perlin_fastfloor(z);
182 int x0 = px & x_mask, x1 = (px+1) & x_mask;
183 int y0 = py & y_mask, y1 = (py+1) & y_mask;
184 int z0 = pz & z_mask, z1 = (pz+1) & z_mask;
185 int r0,r1, r00,r01,r10,r11;
186
187 #define stb__perlin_ease(a) (((a*6-15)*a + 10) * a * a * a)
188
189 x -= px; u = stb__perlin_ease(x);
190 y -= py; v = stb__perlin_ease(y);
191 z -= pz; w = stb__perlin_ease(z);
192
193 r0 = stb__perlin_randtab[x0];
194 r1 = stb__perlin_randtab[x1];
195
196 r00 = stb__perlin_randtab[r0+y0];
197 r01 = stb__perlin_randtab[r0+y1];
198 r10 = stb__perlin_randtab[r1+y0];
199 r11 = stb__perlin_randtab[r1+y1];
200
201 n000 = stb__perlin_grad(stb__perlin_randtab[r00+z0], x , y , z );
202 n001 = stb__perlin_grad(stb__perlin_randtab[r00+z1], x , y , z-1 );
203 n010 = stb__perlin_grad(stb__perlin_randtab[r01+z0], x , y-1, z );
204 n011 = stb__perlin_grad(stb__perlin_randtab[r01+z1], x , y-1, z-1 );
205 n100 = stb__perlin_grad(stb__perlin_randtab[r10+z0], x-1, y , z );
206 n101 = stb__perlin_grad(stb__perlin_randtab[r10+z1], x-1, y , z-1 );
207 n110 = stb__perlin_grad(stb__perlin_randtab[r11+z0], x-1, y-1, z );
208 n111 = stb__perlin_grad(stb__perlin_randtab[r11+z1], x-1, y-1, z-1 );
209
210 n00 = stb__perlin_lerp(n000,n001,w);
211 n01 = stb__perlin_lerp(n010,n011,w);
212 n10 = stb__perlin_lerp(n100,n101,w);
213 n11 = stb__perlin_lerp(n110,n111,w);
214
215 n0 = stb__perlin_lerp(n00,n01,v);
216 n1 = stb__perlin_lerp(n10,n11,v);
217
218 return stb__perlin_lerp(n0,n1,u);
219}
220
221float stb_perlin_ridge_noise3(float x, float y, float z,float lacunarity, float gain, float offset, int octaves,int x_wrap, int y_wrap, int z_wrap)
222{
223 int i;
224 float frequency = 1.0f;
225 float prev = 1.0f;
226 float amplitude = 0.5f;
227 float sum = 0.0f;
228
229 for (i = 0; i < octaves; i++) {
230 float r = (float)(stb_perlin_noise3(x*frequency,y*frequency,z*frequency,x_wrap,y_wrap,z_wrap));
231 r = r<0 ? -r : r; // fabs()
232 r = offset - r;
233 r = r*r;
234 sum += r*amplitude*prev;
235 prev = r;
236 frequency *= lacunarity;
237 amplitude *= gain;
238 }
239 return sum;
240}
241
242float stb_perlin_fbm_noise3(float x, float y, float z,float lacunarity, float gain, int octaves,int x_wrap, int y_wrap, int z_wrap)
243{
244 int i;
245 float frequency = 1.0f;
246 float amplitude = 1.0f;
247 float sum = 0.0f;
248
249 for (i = 0; i < octaves; i++) {
250 sum += stb_perlin_noise3(x*frequency,y*frequency,z*frequency,x_wrap,y_wrap,z_wrap)*amplitude;
251 frequency *= lacunarity;
252 amplitude *= gain;
253 }
254 return sum;
255}
256
257float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves,int x_wrap, int y_wrap, int z_wrap)
258{
259 int i;
260 float frequency = 1.0f;
261 float amplitude = 1.0f;
262 float sum = 0.0f;
263
264 for (i = 0; i < octaves; i++) {
265 float r = stb_perlin_noise3(x*frequency,y*frequency,z*frequency,x_wrap,y_wrap,z_wrap)*amplitude;
266 r = r<0 ? -r : r; // fabs()
267 sum += r;
268 frequency *= lacunarity;
269 amplitude *= gain;
270 }
271 return sum;
272}
273
274#endif // STB_PERLIN_IMPLEMENTATION
275
276/*
277------------------------------------------------------------------------------
278This software is available under 2 licenses -- choose whichever you prefer.
279------------------------------------------------------------------------------
280ALTERNATIVE A - MIT License
281Copyright (c) 2017 Sean Barrett
282Permission is hereby granted, free of charge, to any person obtaining a copy of
283this software and associated documentation files (the "Software"), to deal in
284the Software without restriction, including without limitation the rights to
285use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
286of the Software, and to permit persons to whom the Software is furnished to do
287so, subject to the following conditions:
288The above copyright notice and this permission notice shall be included in all
289copies or substantial portions of the Software.
290THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
291IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
292FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
293AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
294LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
295OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
296SOFTWARE.
297------------------------------------------------------------------------------
298ALTERNATIVE B - Public Domain (www.unlicense.org)
299This is free and unencumbered software released into the public domain.
300Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
301software, either in source code form or as a compiled binary, for any purpose,
302commercial or non-commercial, and by any means.
303In jurisdictions that recognize copyright laws, the author or authors of this
304software dedicate any and all copyright interest in the software to the public
305domain. We make this dedication for the benefit of the public at large and to
306the detriment of our heirs and successors. We intend this dedication to be an
307overt act of relinquishment in perpetuity of all present and future rights to
308this software under copyright law.
309THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
310IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
311FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
312AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
313ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
314WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
315------------------------------------------------------------------------------
316*/
317