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Comparing deliantra/server/common/noise.C (file contents):
Revision 1.5 by root, Sat Apr 23 04:56:46 2011 UTC vs.
Revision 1.25 by root, Wed Dec 5 19:03:26 2018 UTC

1/* 1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG. 2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 * 3 *
4 * Copyright (©) 2017,2018 Marc Alexander Lehmann / the Deliantra team
4 * Copyright (©) 2010,2011 Marc Alexander Lehmann / Robin Redeker / the Deliantra team 5 * Copyright (©) 2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 * 6 *
6 * Deliantra is free software: you can redistribute it and/or modify it under 7 * Deliantra is free software: you can redistribute it and/or modify it under
7 * the terms of the Affero GNU General Public License as published by the 8 * the terms of the Affero GNU General Public License as published by the
8 * Free Software Foundation, either version 3 of the License, or (at your 9 * Free Software Foundation, either version 3 of the License, or (at your
9 * option) any later version. 10 * option) any later version.
10 * 11 *
11 * This program is distributed in the hope that it will be useful, 12 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details. 15 * GNU General Public License for more details.
15 * 16 *
16 * You should have received a copy of the Affero GNU General Public License 17 * You should have received a copy of the Affero GNU General Public License
17 * and the GNU General Public License along with this program. If not, see 18 * and the GNU General Public License along with this program. If not, see
18 * <http://www.gnu.org/licenses/>. 19 * <http://www.gnu.org/licenses/>.
19 * 20 *
20 * The authors can be reached via e-mail to <support@deliantra.net> 21 * The authors can be reached via e-mail to <support@deliantra.net>
21 */ 22 */
22 23
23#include "noise.h" 24#include "noise.h"
24 25
25///////////////////////////////////////////////////////////////////////////// 26/////////////////////////////////////////////////////////////////////////////
26 27
28// perl -e 'for(0..255) { $p = (atan2 1,0) / 64 * $_; printf " %10g, %10g,\n", sin $p, cos $p }' | sort -R
29static const float charges2[256][2] = {
30 -.975702, -.219101, .893224, .449611, .870087, -.492898, .595699, -.803208,
31 .14673, .989177, .995185, .0980171, .91421, -.405241, -.514103, .857729,
32 -.985278, -.170962, -.689541, -.724247, -.427555, .903989, .83147, -.55557,
33 .999699, -.0245412, .634393, .77301, -.514103, -.857729, -.0735646, -.99729,
34 .514103, -.857729, -.595699, -.803208, -.290285, .95694, .595699, .803208,
35 .266713, .963776, -.33689, .941544, .492898, -.870087, -.471397, -.881921,
36 -.99729, -.0735646, .615232, -.788346, -.91421, -.405241, -.575808, .817585,
37 .0980171, .995185, -.980785, .19509, -.122411, -.99248, .0735646, .99729,
38 -.634393, .77301, -.91421, .405241, .99248, .122411, .903989, -.427555,
39 -.24298, .970031, -.857729, .514103, -.359895, .932993, .382683, .92388,
40 .740951, -.671559, -.893224, .449611, -.95694, -.290285, -.975702, .219101,
41 -.970031, .24298, .999699, .0245412, -.405241, .91421, .985278, .170962,
42 .382683, -.92388, .95694, -.290285, .707107, -.707107, -.817585, -.575808,
43 -.989177, .14673, -.19509, -.980785, -.359895, -.932993, .313682, .949528,
44 -.0980171, .995185, 1, 6.12323e-17, .963776, -.266713, .998795, -.0490677,
45 -.998795, -.0490677, -.970031, -.24298, -.55557, .83147, -.14673, .989177,
46 -.83147, -.55557, -.995185, -.0980171, .870087, .492898, .941544, -.33689,
47 .575808, -.817585, .33689, .941544, .19509, -.980785, 0, 1,
48 .219101, -.975702, -.83147, .55557, .757209, -.653173, -.95694, .290285,
49 -.266713, .963776, -.0490677, .998795, .405241, .91421, -.405241, -.91421,
50 -.689541, .724247, -.534998, -.844854, -.99248, -.122411, .724247, .689541,
51 .492898, .870087, .817585, -.575808, .740951, .671559, -.33689, -.941544,
52 .95694, .290285, .77301, -.634393, .0245412, -.999699, -.77301, -.634393,
53 -.382683, .92388, -.24298, -.970031, -.893224, -.449611, .449611, .893224,
54 .975702, -.219101, -.382683, -.92388, .844854, .534998, -.803208, -.595699,
55 .941544, .33689, .963776, .266713, .932993, .359895, -.0735646, .99729,
56 .634393, -.77301, .405241, -.91421, .33689, -.941544, .99729, .0735646,
57 1.22465e-16, -1, -.941544, -.33689, .0490677, -.998795, -.313682, .949528,
58 .92388, .382683, -.999699, .0245412, .0245412, .999699, .653173, .757209,
59 -.803208, .595699, .980785, -.19509, .817585, .575808, .975702, .219101,
60 -.615232, -.788346, .99248, -.122411, .998795, .0490677, -.707107, .707107,
61 .803208, -.595699, .671559, .740951, -.757209, -.653173, -.949528, .313682,
62 -.989177, -.14673, -.817585, .575808, -.14673, -.989177, -1, -1.83697e-16,
63 .290285, .95694, -.932993, -.359895, .24298, -.970031, .170962, .985278,
64 -.671559, -.740951, .427555, .903989, .427555, -.903989, -.941544, .33689,
65 -.492898, -.870087, -.266713, -.963776, .857729, -.514103, -.724247, .689541,
66 .724247, -.689541, -.653173, .757209, .689541, -.724247, .949528, -.313682,
67 -.19509, .980785, -.740951, .671559, -.999699, -.0245412, .689541, .724247,
68 .803208, .595699, -.170962, .985278, .0735646, -.99729, .970031, -.24298,
69 -.170962, -.985278, .471397, .881921, .91421, .405241, .893224, -.449611,
70 .0490677, .998795, -.615232, .788346, -.998795, .0490677, -.427555, -.903989,
71 -.0245412, .999699, -.534998, .844854, -.313682, -.949528, -.55557, -.83147,
72 -.903989, -.427555, -.724247, -.689541, -.740951, -.671559, .985278, -.170962,
73 -.857729, -.514103, -.99729, .0735646, .881921, -.471397, .534998, .844854,
74 .359895, -.932993, .77301, .634393, .99729, -.0735646, .290285, -.95694,
75 .575808, .817585, .757209, .653173, .903989, .427555, -.995185, .0980171,
76 -.903989, .427555, -.844854, .534998, -.707107, -.707107, -.92388, .382683,
77 -.653173, -.757209, -.881921, -.471397, -.219101, .975702, -.595699, .803208,
78 .0980171, -.995185, -.788346, .615232, -.0980171, -.995185, -.985278, .170962,
79 .122411, .99248, -.449611, -.893224, .170962, -.985278, .788346, .615232,
80 -.492898, .870087, .671559, -.740951, .449611, -.893224, -.757209, .653173,
81 .83147, .55557, -.290285, -.95694, -.932993, .359895, -.870087, -.492898,
82 .266713, -.963776, -.881921, .471397, -.77301, .634393, -.471397, .881921,
83 .844854, -.534998, .707107, .707107, .534998, -.844854, .514103, .857729,
84 .14673, -.989177, .980785, .19509, -.122411, .99248, -.449611, .893224,
85 .995185, -.0980171, -.634393, -.77301, .857729, .514103, .55557, .83147,
86 -.92388, -.382683, -.844854, -.534998, -.963776, .266713, .989177, -.14673,
87 .313682, -.949528, .359895, .932993, .24298, .970031, -.949528, -.313682,
88 .932993, -.359895, .55557, -.83147, .615232, .788346, -.788346, -.615232,
89 -.0245412, -.999699, -.219101, -.975702, .788346, -.615232, -.99248, .122411,
90 -.671559, .740951, -.870087, .492898, .970031, .24298, .881921, .471397,
91 .122411, -.99248, .471397, -.881921, .19509, .980785, -.963776, -.266713,
92 .92388, -.382683, .989177, .14673, -.575808, -.817585, .219101, .975702,
93 -.0490677, -.998795, -.980785, -.19509, .949528, .313682, .653173, -.757209,
94};
95
27// http://www-wales.ch.cam.ac.uk/~wales/CCD/Thomson/table.html, random permutation 96// http://www-wales.ch.cam.ac.uk/~wales/CCD/Thomson/table.html, random permutation
97// used as gradient vectors for noise3d
28static const float charges[256][3] = { 98static const float charges3[256][3] = {
29 6.32096444e-01, -6.11406706e-01, 4.76062943e-01, 5.19172442e-01, 8.08229585e-01, -2.77893708e-01, 99 6.32096444e-01, -6.11406706e-01, 4.76062943e-01, 5.19172442e-01, 8.08229585e-01, -2.77893708e-01,
30 -8.81072422e-01, -4.68301230e-01, 6.63727731e-02, -1.92122323e-01, 9.81341519e-01, -7.60505942e-03, 100 -8.81072422e-01, -4.68301230e-01, 6.63727731e-02, -1.92122323e-01, 9.81341519e-01, -7.60505942e-03,
31 -2.57478265e-01, 9.34157733e-01, -2.47091628e-01, 8.75501090e-01, -1.48087600e-01, -4.59965112e-01, 101 -2.57478265e-01, 9.34157733e-01, -2.47091628e-01, 8.75501090e-01, -1.48087600e-01, -4.59965112e-01,
32 -6.44086082e-01, 3.21868600e-01, 6.93940720e-01, -4.42053435e-01, -1.94962529e-01, -8.75544615e-01, 102 -6.44086082e-01, 3.21868600e-01, 6.93940720e-01, -4.42053435e-01, -1.94962529e-01, -8.75544615e-01,
33 -6.86776297e-01, 5.34610386e-01, -4.92473403e-01, -8.45541961e-01, -2.41708225e-01, 4.76062943e-01, 103 -6.86776297e-01, 5.34610386e-01, -4.92473403e-01, -8.45541961e-01, -2.41708225e-01, 4.76062943e-01,
… …
154 4.98855035e-01, -3.98703643e-01, 7.69531714e-01, 2.55373649e-01, -7.56251592e-02, 9.63880249e-01, 224 4.98855035e-01, -3.98703643e-01, 7.69531714e-01, 2.55373649e-01, -7.56251592e-02, 9.63880249e-01,
155 -1.51053916e-01, 3.85469253e-01, -9.10272580e-01, 6.78644990e-01, -7.26064181e-01, 1.10778074e-01, 225 -1.51053916e-01, 3.85469253e-01, -9.10272580e-01, 6.78644990e-01, -7.26064181e-01, 1.10778074e-01,
156 -3.07350590e-01, -9.14677987e-01, 2.62487703e-01, 5.60298616e-01, 1.74821302e-01, 8.09631381e-01, 226 -3.07350590e-01, -9.14677987e-01, 2.62487703e-01, 5.60298616e-01, 1.74821302e-01, 8.09631381e-01,
157}; 227};
158 228
159static vec2d 229/////////////////////////////////////////////////////////////////////////////
160floor (vec2d v)
161{
162 return vec2d (std::floor (v[0]), std::floor (v[1]));
163}
164 230
165static vec3d 231template<int N, typename T>
166floor (vec3d v) 232void
233permutation<N,T>::seed (seedable_rand_gen &rng)
167{ 234{
168 return vec3d (std::floor (v[0]), std::floor (v[1]), std::floor (v[2])); 235 for (int i = 0; i < N; ++i)
169} 236 pmap[i] = i;
170 237
171noise_gen<vec2d>::noise_gen (uint32_t seed) 238 // fisher-yates to randomly perturb
239 for (int i = N; --i; )
240 ::swap (pmap[i], pmap[rng (i + 1)]);
241}
242
243template class permutation<256, uint8_t>;
244
245/////////////////////////////////////////////////////////////////////////////
246
247template<class vec_t>
248void
249noise_gen_base<vec_t>::seed (seedable_rand_gen &rng)
250{
251 for (int i = 0; i < ecb_array_length (rvmap); ++i)
252 rvmap[i].seed (rng);
253}
254
255template<class vec_t>
256void
257noise_gen_base<vec_t>::seed (seed_t seed)
172{ 258{
173 seedable_rand_gen rng (seed); 259 seedable_rand_gen rng (seed);
174 260
175#if 1 261 this->seed (rng);
176 for (int i = 0; i < 256; ++i)
177 {
178 vec2d rv (rng () - 0.5f, rng () - 0.5f);
179
180 // normalise
181 float mag = 1.f / sqrtf (dot (rv, rv));
182
183 rv[0] *= mag;
184 rv[1] *= mag;
185
186 rvec[i] = rv;
187 }
188#endif
189
190#if 0
191 float offset = rng () * 3.14159265;
192
193 for (int i = 0; i < 256; ++i)
194 {
195 float phi = i * (3.14159265 * 2 / 256) + offset;
196
197 rvec[i][0] = sinf (phi);
198 rvec[i][1] = -cosf (phi);
199 }
200
201 // fisher-yates to randomly perturb
202 for (int i = 256; --i; )
203 ::swap (rvec [i], rvec [rng (i + 1)]);
204#endif
205
206 rvmap[0].seed (rng);
207 rvmap[1].seed (rng);
208} 262}
209 263
264template<>
210vec2d::T_numtype 265vec2d::T_numtype
211noise_gen<vec2d>::operator() (vec2d P) 266noise_gen_base<vec2d>::operator() (vec2d P, uint32_t seed)
212{ 267{
213 vec2d I = floor (P); 268 vec2d I = floor (P);
214 vec2d F = P - I; 269 vec2d F = P - I;
215 270
216 float v = 0; 271 value_t v = 0;
272
273 seed *= 3039177861;
274 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
275 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
276
277 uint8_t h2 = rvmap[2](seed);
217 278
218 for (int j = -1; j <= 2; ++j) 279 for (int j = -1; j <= 2; ++j)
280 {
281 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
282
219 for (int i = -1; i <= 2; ++i) 283 for (int i = -1; i <= 2; ++i)
220 { 284 {
221 vec2d A = F - vec2d (i, j); 285 vec2d A = F - vec2d (i, j);
222
223 float d = dot (A, A); 286 value_t d = dot (A, A);
224 287
225 if (d < 4) 288 if (d < 4)
226 { 289 {
227 float t1 = 1 - d / 4; 290 value_t t1 = 1 - d / 4;
228 float t2 = t1 * t1; 291 value_t t2 = t1 * t1;
229 float t4 = t2 * t2; 292 value_t t4 = t2 * t2;
230 293
231 float p = (4 * t1 - 3) * t4; 294 value_t p = (4 * t1 - 3) * t4;
232 295
233 int h = rvmap [0](I[0] + i) ^ rvmap [1](I[1] + j); 296 uint8_t h = rvmap[0](i0 + i) ^ h1;
234 vec2d G = rvec [h & 0xff]; 297 vec2d G = charges2[h & 0xff];
235 298
236 v += dot (A, G) * p; 299 v += dot (A, G) * p;
237 } 300 }
238 } 301 }
302 }
239 303
240 return clamp (v, -.9999999f, .9999999f); 304 return v;
241} 305}
242 306
243///////////////////////////////////////////////////////////////////////////// 307/////////////////////////////////////////////////////////////////////////////
244 308
245noise_gen<vec3d>::noise_gen (uint32_t seed) 309template<>
246{
247 seedable_rand_gen rng (seed);
248
249 rvmap [0].seed (rng);
250 rvmap [1].seed (rng);
251 rvmap [2].seed (rng);
252}
253
254vec3d::T_numtype 310vec3d::T_numtype
255noise_gen<vec3d>::operator() (vec3d P) 311noise_gen_base<vec3d>::operator() (vec3d P, uint32_t seed)
256{ 312{
257 vec3d I = floor (P); 313 vec3d I = floor (P);
258 vec3d F = P - I; 314 vec3d F = P - I;
259 315
260 float v = 0; 316 seed *= 3039177861;
317 uint8_t i2 = uint8_t (I[2]) + (seed >> 24);
318 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
319 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
261 320
262 for (int j = -1; j <= 2; ++j) 321 uint8_t h3 = rvmap[3](seed);
263 for (int i = -1; i <= 2; ++i) 322
323 value_t v = 0;
324
264 for (int k = -1; k <= 2; ++k) 325 for (int k = -1; k <= 2; ++k)
326 {
327 uint8_t h2 = rvmap[2](i2 + k) ^ h3;
328
329 for (int j = -1; j <= 2; ++j)
265 { 330 {
266 vec3d A = F - vec3d (i, j, k); 331 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
267 float d = dot (A, A);
268 332
269 if (d < 4) 333 for (int i = -1; i <= 2; ++i)
270 { 334 {
271 float t1 = 1 - d / 4;
272 float t2 = t1 * t1;
273 float t4 = t2 * t2;
274
275 // (4t⁵ - 3t⁴)
276 float p = (4 * t1 - 3) * t4;
277
278 int h = rvmap[0](I[0] + i) ^ rvmap[1](I[1] + j) ^ rvmap[2](I[2] + k);
279 const float *G = charges[h & 0xff];
280
281 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
282 }
283 }
284
285 return clamp (v * 2, -.9999999f, .9999999f);
286}
287
288vec3d::T_numtype
289noise_gen<vec3d>::operator() (vec3d P, vec3d N)
290{
291 vec3d I = floor (P);
292 vec3d F = P - I;
293
294 float v = 0;
295
296 for (int j = -1; j <= 2; ++j)
297 for (int i = -1; i <= 2; ++i)
298 for (int k = -1; k <= 2; ++k)
299 {
300 vec3d D = F - vec3d (i, j, k); 335 vec3d A = F - vec3d (i, j, k);
301 float e = dot (D, N);
302 float o = 1 - abs (e);
303
304 if (o > 0)
305 {
306 vec3d A = D - e * N;
307 float d = dot (A, A); 336 value_t d = dot (A, A);
308 337
309 if (d < 4) 338 if (d < 4)
310 { 339 {
311 float t1 = 1 - d / 4; 340 value_t t1 = 1 - d / 4;
312 float t2 = t1 * t1; 341 value_t t2 = t1 * t1;
313 float t4 = t2 * t2; 342 value_t t4 = t2 * t2;
314 343
315 float o2 = o * o;
316
317 // (4t⁵ - 3t⁴) * (3o³ - 2o²) 344 // (4t⁵ - 3t⁴)
318 // alternative? ((o * 6 - 15) * o + 10) * o³ 345 value_t p = (4 * t1 - 3) * t4;
319 float p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
320 346
321 int h = rvmap[0](I[0] + i) ^ rvmap[1](I[1] + j) ^ rvmap[2](I[2] + k); 347 uint8_t h = rvmap[0](i0 + i) ^ h1;
322 const float *G = charges[h & 0xff]; 348 const value_t *G = charges3[h & 0xff];
323 349
324 v += dot (A, vec3d (G[0], G[1], G[2])) * p; 350 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
325 } 351 }
326 } 352 }
327 } 353 }
354 }
328 355
329 return clamp (v, -.9999999f, .9999999f); 356 return v * 2;
330} 357}
331 358
332template class noise_gen<vec2d>; 359vec3d::T_numtype
333template class noise_gen<vec3d>; 360noise_gen<vec3d>::operator() (vec3d P, vec3d N, uint32_t seed)
361{
362 vec3d I = floor (P);
363 vec3d F = P - I;
364
365 seed *= 3039177861;
366 uint8_t i2 = uint8_t (I[2]) + (seed >> 24);
367 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
368 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
369
370 uint8_t h3 = rvmap[3](seed);
371
372 value_t v = 0;
373
374 for (int k = -1; k <= 2; ++k)
375 {
376 uint8_t h2 = rvmap[2](i2 + k) ^ h3;
377
378 for (int j = -1; j <= 2; ++j)
379 {
380 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
381
382 for (int i = -1; i <= 2; ++i)
383 {
384 vec3d D = F - vec3d (i, j, k);
385 value_t e = dot (D, N);
386 value_t o = 1 - abs (e);
387
388 if (o > 0)
389 {
390 vec3d A = D - e * N;
391 value_t d = dot (A, A);
392
393 if (d < 4)
394 {
395 value_t t1 = 1 - d / 4;
396 value_t t2 = t1 * t1;
397 value_t t4 = t2 * t2;
398
399 value_t o2 = o * o;
400
401 // (4t⁵ - 3t⁴) * (3o³ - 2o²)
402 // alternative? ((o * 6 - 15) * o + 10) * o³
403 value_t p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
404
405 uint8_t h = rvmap[0](i0 + i) ^ h1;
406 const value_t *G = charges3[h & 0xff];
407
408 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
409 }
410 }
411 }
412 }
413 }
414
415 return v;
416}
334 417
335///////////////////////////////////////////////////////////////////////////// 418/////////////////////////////////////////////////////////////////////////////
336 419
337template<class vec_t> 420template<class vec_t>
338static vec_t 421frac_gen<vec_t>::frac_gen (int octaves, value_t lacunarity, value_t hurst_expo, seed_t seed)
339ith_octave (vec_t P, int i) 422: octaves (octaves), lac (lacunarity), h (hurst_expo)
340{ 423{
341 vec_t r = P; 424 this->seed (seed);
342 r[0] += i;
343 return r;
344}
345 425
346template<class vec_t>
347frac_gen<vec_t>::frac_gen (value_t hurst_expo, value_t lacunarity)
348: h (hurst_expo), lac (lacunarity), noise_gen<vec_t> (0)
349{
350 value_t exsum = 0; 426 value_t exsum = 0;
427 value_t phi = noise (vec_t (value_t (0))) * 0.5 + 1;
351 428
352 for (int i = 0; i < MAX_OCTAVES; ++i) 429 for (int i = 0; i < octaves; ++i)
353 { 430 {
354 ex [i] = powf (lac, -h * i); 431 ex [i] = pow (lac, -h * i);
355 exsum += ex [i]; 432 exsum += ex [i];
356 fbm_mul [i] = 0.5f / (exsum * 0.75f); // .75f is a heuristic 433 fbm_mul [i] = 0.5 / (exsum * 0.75); // .75 is a heuristic
357 rot [i].set (0.4488f * i); 434 rot [i].set (phi * i + 1);
358 } 435 }
359} 436}
360 437
361template<class vec_t> 438template<class vec_t>
362typename frac_gen<vec_t>::value_t 439typename frac_gen<vec_t>::value_t
363frac_gen<vec_t>::fBm (vec_t P, int octaves) 440frac_gen<vec_t>::fBm (vec_t P)
364{ 441{
365 value_t v = 0.f; 442 value_t v = 0;
366 443
367 for (int i = 0; i < octaves; ++i) 444 for (int i = 0; i < octaves; ++i)
368 { 445 {
369 rot [i](P); 446 rot [i](P);
370 v += noise (ith_octave (P, i)) * ex [i]; 447 v += noise (P, i) * ex [i];
371 P *= lac; 448 P *= lac;
372 } 449 }
373 450
374 return clamp (v * fbm_mul [octaves - 1] + 0.5f, 0.f, .9999999f); 451 return v * fbm_mul [octaves - 1];
375} 452}
376 453
377template<class vec_t> 454template<class vec_t>
378typename frac_gen<vec_t>::value_t 455typename frac_gen<vec_t>::value_t
379frac_gen<vec_t>::turbulence (vec_t P, int octaves) 456frac_gen<vec_t>::turbulence (vec_t P)
380{ 457{
381 value_t v = 0.f; 458 value_t v = 0;
382 459
383 for (int i = 0; i < octaves; ++i) 460 for (int i = 0; i < octaves; ++i)
384 { 461 {
385 rot [i](P); 462 rot [i](P);
386 v += abs (noise (ith_octave (P, i))) * ex [i]; 463 v += abs (noise (P, i)) * ex [i];
387 P *= lac; 464 P *= lac;
388 } 465 }
389 466
390 return clamp (v * fbm_mul [octaves - 1] * 2.f, 0.f, .9999999f); 467 return v * fbm_mul [octaves - 1] * (0.5 / noise_gen<vec_t>::abs_avg ());
391} 468}
392 469
393template<class vec_t> 470template<class vec_t>
394typename frac_gen<vec_t>::value_t 471typename frac_gen<vec_t>::value_t
395frac_gen<vec_t>::multifractal (vec_t P, int octaves, value_t offset) 472frac_gen<vec_t>::multifractal (vec_t P, value_t offset)
396{ 473{
397 value_t v = 1.f; 474 value_t v = 1;
398 475
399 for (int i = 0; i < octaves; ++i) 476 for (int i = 0; i < octaves; ++i)
400 { 477 {
401 rot [i](P); 478 rot [i](P);
402 v *= noise (P) * ex [i] + offset; 479 v *= noise (P) * ex [i] + offset;
403 P *= lac; 480 P *= lac;
404 } 481 }
405 482
406 return clamp (v * 0.5f, 0.f, .9999999f); 483 return v * value_t (0.5);
407} 484}
408 485
409template<class vec_t> 486template<class vec_t>
410typename frac_gen<vec_t>::value_t 487typename frac_gen<vec_t>::value_t
411frac_gen<vec_t>::heterofractal (vec_t P, int octaves, value_t offset) 488frac_gen<vec_t>::heterofractal (vec_t P, value_t offset)
412{ 489{
413 value_t v = noise (P) + offset; 490 value_t v = noise (P) + offset;
414 int i;
415 491
416 for (i = 1; i < octaves; ++i) 492 for (int i = 1; i < octaves; ++i)
417 { 493 {
418 rot [i](P); 494 rot [i](P);
419 P *= lac; 495 P *= lac;
420 v += v * (noise (P) * ex [i] + offset); 496 v += v * (noise (P) * ex [i] + offset);
421 } 497 }
422 498
423 return v / powf (2., octaves); 499 return v / (1 << octaves);
424} 500}
425 501
426template<class vec_t> 502template<class vec_t>
427typename frac_gen<vec_t>::value_t 503typename frac_gen<vec_t>::value_t
428frac_gen<vec_t>::hybridfractal (vec_t P, int octaves, value_t offset, value_t gain) 504frac_gen<vec_t>::hybridfractal (vec_t P, value_t offset, value_t gain)
429{ 505{
430 value_t v = (noise (P) + offset) * ex [0]; 506 value_t v = (noise (P) + offset) * ex [0];
431 value_t weight = v; 507 value_t weight = v;
432 int i;
433 508
434 for (i = 1; i < octaves; ++i) 509 for (int i = 1; i < octaves; ++i)
435 { 510 {
436 rot [i](P); 511 rot [i](P);
437 P *= lac; 512 P *= lac;
438 513
439 min_it (weight, 1.f); 514 min_it (weight, 1);
440 515
441 value_t sig = (noise (P) + offset) * ex [i]; 516 value_t sig = (noise (P) + offset) * ex [i];
442 v += weight * sig; 517 v += weight * sig;
443 weight *= gain * sig; 518 weight *= gain * sig;
444 } 519 }
445 520
446 return clamp (v * 0.5f + 0.5f, 0.f, .9999999f); 521 return v * value_t (0.5) + value_t (0.5);
447} 522}
448 523
449template<class vec_t> 524template<class vec_t>
450typename frac_gen<vec_t>::value_t 525typename frac_gen<vec_t>::value_t
451frac_gen<vec_t>::ridgedmultifractal (vec_t P, int octaves, value_t offset, value_t gain) 526frac_gen<vec_t>::ridgedmultifractal (vec_t P, value_t offset, value_t gain)
452{ 527{
453 value_t sig = offset - abs (noise (P)); 528 value_t sig = offset - abs (noise (P));
454 sig *= sig; 529 sig *= sig;
455 value_t v = sig; 530 value_t v = sig;
456 531
457 for (int i = 1; i < octaves; ++i) 532 for (int i = 1; i < octaves; ++i)
458 { 533 {
459 rot [i](P); 534 rot [i](P);
460 P *= lac; 535 P *= lac;
461 536
537 // weight higher octaves by previous signal
462 value_t w = clamp (sig * gain, 0.f, 1.f); 538 value_t w = clamp (sig * gain, 0, 1);
463 539
464 sig = offset - abs (noise (P)); 540 sig = offset - abs (noise (P));
465 sig *= sig; 541 sig *= sig;
466 sig *= w; 542 sig *= w;
467 543
468 v += sig * ex [i]; 544 v += sig * ex [i];
469 } 545 }
470 546
471 return clamp (v * 0.25f, 0.f, .9999999f); 547 return v * value_t (0.25);
548}
549
550template<class vec_t>
551typename frac_gen<vec_t>::value_t
552frac_gen<vec_t>::billowfractal (vec_t P, value_t offset, value_t gain)
553{
554 value_t v = 0;
555
556 offset += 2 * noise_gen<vec_t>::abs_avg () - 1;
557
558 for (int i = 0; i < octaves; ++i)
559 {
560 rot [i](P);
561 v += (abs (noise (P, i)) * gain - offset) * ex [i];
562 P *= lac;
563 }
564
565 return v;
472} 566}
473 567
474// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2 568// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2
475template<class vec_t> 569template<class vec_t>
476typename frac_gen<vec_t>::value_t 570typename frac_gen<vec_t>::value_t
477frac_gen<vec_t>::terrain (vec_t P, int octaves) 571frac_gen<vec_t>::terrain (vec_t P)
478{ 572{
479 value_t v = 0.f; 573 value_t v = 0;
480 574
481 for (int i = 0; i < octaves; ++i) 575 for (int i = 0; i < octaves; ++i)
482 { 576 {
483 rot [i](P); 577 rot [i](P);
484 v += noise (P) * ex [i]; 578 v += noise (P) * ex [i];
485 P *= lac; 579 P *= lac;
486 } 580 }
487 581
488 v *= fbm_mul [octaves - 1]; 582 v *= fbm_mul [octaves - 1];
489 583
490 return v <= 0.f ? - powf (-v, 0.7f) : powf (v, 1. + noise (P) * v); 584 return v <= 0 ? - pow (-v, 0.7) : pow (v, 1 + noise (P) * v);
491} 585}
492 586
493template<class vec_t> 587template<class vec_t>
494typename frac_gen<vec_t>::value_t 588typename frac_gen<vec_t>::value_t
495frac_gen<vec_t>::terrain2 (vec_t P, int octaves) 589frac_gen<vec_t>::terrain2 (vec_t P)
496{ 590{
497 value_t a = fBm (P, octaves); 591 value_t a = fBm (P);
498 value_t b = ridgedmultifractal (P, octaves, 1, 8); 592 value_t b = ridgedmultifractal (P, 1, 8);
499 value_t fade = fBm (P + vec_t(10.3), octaves); 593 value_t fade = fBm (P + vec_t(10.3));
500 594
501 const value_t width = 0.05f; 595 const value_t width = 0.05;
502 596
503 if (fade > 0.5f + width) 597 if (fade > 0.5 + width)
504 return a; 598 return a;
505 else if (fade < 0.5f - width) 599 else if (fade < 0.5 - width)
506 return b; 600 return b;
507 601
508 fade = (fade - 0.5f + width) / (width * 2); 602 fade = (fade - 0.5 + width) / (width * 2);
509 603
510 // sigmoidal curve 604 // sigmoidal curve
511 fade = fade * fade * 2 * (1.5f - fade); 605 fade = fade * fade * 2 * (1.5 - fade);
512 606
513 return a * fade + b * (1 - fade); 607 return a * fade + b * (1 - fade);
514} 608}
515 609
516template class frac_gen<vec2d>; 610template class frac_gen<vec2d>;
517template class frac_gen<vec3d>; 611template class frac_gen<vec3d>;
518 612
519/////////////////////////////////////////////////////////////////////////////
520
521#if 0
522void hack(); void hack()
523{
524 frac_gen<vec2d> gen (0.5, 2);
525 frac_gen<vec3d> gen3;
526
527#if 0
528 int N = 1024;
529
530 printf ("P5 %d %d 255\n", N, N);
531 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
532 for (int y = 0; y < N; ++y)
533 {
534 if (!(y&63))fprintf (stderr, "y %d\n", y);//D
535 for (int x = 0; x < N; ++x)
536 {
537 //putc (127 * n.noise (x * 0.1, y * 0.1, 0, 0,0,1) + 128, stdout);
538 //putc (256 * gen.terrain2 (x * 0.004, y * 0.004, 8), stdout);
539 //putc (256 * gen.fBm (x * 0.01, y * 0.01, 3), stdout);
540 //putc (256 * gen.turbulence (x * 0.004 - 1, y * 0.004 - 1, 8), stdout);
541 //putc (256 * gen.heterofractal (x * 0.008, y * 0.008, 8, 0.9), stdout);
542
543 // mountais or somesuch(?)
544 //putc (256 * gen.hybridfractal (x * 0.01, y * 0.01, 8, -.4, -4), stdout);
545
546 // temperature
547 //putc (256 * gen.fBm (x * 0.002, y * 0.002, 2), stdout);
548 // rain
549 //putc (256 * gen.ridgedmultifractal (x * 0.01, y * 0.01, 3, 1.03, 2), stdout);
550 }
551 }
552#else
553 int N = 512;
554
555 //printf ("P6 %d %d 255\n", N, N);
556 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
557 for (int z = 0; z < N; ++z)
558 {
559 if (!(z&7))fprintf (stderr, "z %d\n", z);//D
560 for (int y = 0; y < N; ++y)
561 for (int x = 0; x < N; ++x)
562 {
563 float v = gen3.ridgedmultifractal (vec3d (x * 0.01 + 0.2, y * 0.01 + 0.2, z * 0.01 + 0.2), 3, 1.03, 2) * 2;
564
565#if 0
566 if (z < 64)
567 v = v * (z * z) / (64 * 64);
568#endif
569
570 if (v <= 0.9999)
571 continue;
572
573 float r[4];
574 int i[4];
575
576 r[0] = x;
577 r[1] = y;
578 r[2] = z;
579 r[3] = v;
580
581 memcpy (i, r, 16);
582
583 i[0] = htonl (i[0]);
584 i[1] = htonl (i[1]);
585 i[2] = htonl (i[2]);
586 i[3] = htonl (i[3]);
587
588 fwrite (i, 4*4, 1, stdout);
589 }
590 }
591#endif
592
593 exit (0);
594}
595#endif

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