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Comparing deliantra/server/common/noise.C (file contents):
Revision 1.6 by root, Sat Apr 23 05:42:11 2011 UTC vs.
Revision 1.23 by root, Sat Nov 17 23:40:00 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
28// used as gradient vectors for noise3d 97// used as gradient vectors for noise3d
29static const float charges[256][3] = { 98static const float charges3[256][3] = {
30 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,
31 -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,
32 -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,
33 -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,
34 -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,
… …
158}; 227};
159 228
160///////////////////////////////////////////////////////////////////////////// 229/////////////////////////////////////////////////////////////////////////////
161 230
162template<int N, typename T> 231template<int N, typename T>
163template<class random_generator>
164void 232void
165permutation<N,T>::seed (random_generator &rng) 233permutation<N,T>::seed (seedable_rand_gen &rng)
166{ 234{
167 for (int i = 0; i < N; ++i) 235 for (int i = 0; i < N; ++i)
168 pmap[i] = i; 236 pmap[i] = i;
169 237
170 // fisher-yates to randomly perturb 238 // fisher-yates to randomly perturb
… …
174 242
175template class permutation<256, uint8_t>; 243template class permutation<256, uint8_t>;
176 244
177///////////////////////////////////////////////////////////////////////////// 245/////////////////////////////////////////////////////////////////////////////
178 246
179static vec2d 247template<class vec_t>
180floor (vec2d v) 248void
249noise_gen_base<vec_t>::seed (seedable_rand_gen &rng)
181{ 250{
182 return vec2d (std::floor (v[0]), std::floor (v[1])); 251 for (int i = 0; i < array_length (rvmap); ++i)
252 rvmap[i].seed (rng);
183} 253}
184 254
185static vec3d 255template<class vec_t>
186floor (vec3d v) 256void
187{ 257noise_gen_base<vec_t>::seed (seed_t seed)
188 return vec3d (std::floor (v[0]), std::floor (v[1]), std::floor (v[2]));
189}
190
191noise_gen<vec2d>::noise_gen (uint32_t seed)
192{ 258{
193 seedable_rand_gen rng (seed); 259 seedable_rand_gen rng (seed);
194 260
195#if 0 261 this->seed (rng);
196 for (int i = 0; i < 256; ++i)
197 {
198 vec2d rv (rng () - 0.5f, rng () - 0.5f);
199
200 // normalise
201 float mag = 1.f / sqrtf (dot (rv, rv));
202
203 rv[0] *= mag;
204 rv[1] *= mag;
205
206 rvec[i] = rv;
207 }
208#endif
209
210#if 1
211 float offset = rng () * M_PI;
212
213 for (int i = 0; i < 256; ++i)
214 {
215 float phi = i * (M_PI * 2 / 256) + offset;
216
217 rvec[i][0] = sinf (phi);
218 rvec[i][1] = -cosf (phi);
219 }
220
221 // fisher-yates to randomly perturb
222 for (int i = 256; --i; )
223 ::swap (rvec [i], rvec [rng (i + 1)]);
224#endif
225
226 rvmap[0].seed (rng);
227 rvmap[1].seed (rng);
228} 262}
229 263
264template<>
230vec2d::T_numtype 265vec2d::T_numtype
231noise_gen<vec2d>::operator() (vec2d P) 266noise_gen_base<vec2d>::operator() (vec2d P, uint32_t seed)
232{ 267{
233 vec2d I = floor (P); 268 vec2d I = floor (P);
234 vec2d F = P - I; 269 vec2d F = P - I;
235 270
236 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);
237 278
238 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
239 for (int i = -1; i <= 2; ++i) 283 for (int i = -1; i <= 2; ++i)
240 { 284 {
241 vec2d A = F - vec2d (i, j); 285 vec2d A = F - vec2d (i, j);
242
243 float d = dot (A, A); 286 value_t d = dot (A, A);
244 287
245 if (d < 4) 288 if (d < 4)
246 { 289 {
247 float t1 = 1 - d / 4; 290 value_t t1 = 1 - d / 4;
248 float t2 = t1 * t1; 291 value_t t2 = t1 * t1;
249 float t4 = t2 * t2; 292 value_t t4 = t2 * t2;
250 293
251 float p = (4 * t1 - 3) * t4; 294 value_t p = (4 * t1 - 3) * t4;
252 295
253 int h = rvmap [0](I[0] + i) ^ rvmap [1](I[1] + j); 296 uint8_t h = rvmap[0](i0 + i) ^ h1;
254 vec2d G = rvec [h & 0xff]; 297 vec2d G = charges2[h & 0xff];
255 298
256 v += dot (A, G) * p; 299 v += dot (A, G) * p;
257 } 300 }
258 } 301 }
302 }
259 303
260 return clamp (v, -.9999999f, .9999999f); 304 return v;
261} 305}
262 306
263///////////////////////////////////////////////////////////////////////////// 307/////////////////////////////////////////////////////////////////////////////
264 308
265noise_gen<vec3d>::noise_gen (uint32_t seed) 309template<>
266{
267 seedable_rand_gen rng (seed);
268
269 rvmap [0].seed (rng);
270 rvmap [1].seed (rng);
271 rvmap [2].seed (rng);
272}
273
274vec3d::T_numtype 310vec3d::T_numtype
275noise_gen<vec3d>::operator() (vec3d P) 311noise_gen_base<vec3d>::operator() (vec3d P, uint32_t seed)
276{ 312{
277 vec3d I = floor (P); 313 vec3d I = floor (P);
278 vec3d F = P - I; 314 vec3d F = P - I;
279 315
280 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);
281 320
282 for (int j = -1; j <= 2; ++j) 321 uint8_t h3 = rvmap[3](seed);
283 for (int i = -1; i <= 2; ++i) 322
323 value_t v = 0;
324
284 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)
285 { 330 {
286 vec3d A = F - vec3d (i, j, k); 331 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
287 float d = dot (A, A);
288 332
289 if (d < 4) 333 for (int i = -1; i <= 2; ++i)
290 { 334 {
291 float t1 = 1 - d / 4;
292 float t2 = t1 * t1;
293 float t4 = t2 * t2;
294
295 // (4t⁵ - 3t⁴)
296 float p = (4 * t1 - 3) * t4;
297
298 int h = rvmap[0](I[0] + i) ^ rvmap[1](I[1] + j) ^ rvmap[2](I[2] + k);
299 const float *G = charges[h & 0xff];
300
301 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
302 }
303 }
304
305 return clamp (v * 2, -.9999999f, .9999999f);
306}
307
308vec3d::T_numtype
309noise_gen<vec3d>::operator() (vec3d P, vec3d N)
310{
311 vec3d I = floor (P);
312 vec3d F = P - I;
313
314 float v = 0;
315
316 for (int j = -1; j <= 2; ++j)
317 for (int i = -1; i <= 2; ++i)
318 for (int k = -1; k <= 2; ++k)
319 {
320 vec3d D = F - vec3d (i, j, k); 335 vec3d A = F - vec3d (i, j, k);
321 float e = dot (D, N);
322 float o = 1 - abs (e);
323
324 if (o > 0)
325 {
326 vec3d A = D - e * N;
327 float d = dot (A, A); 336 value_t d = dot (A, A);
328 337
329 if (d < 4) 338 if (d < 4)
330 { 339 {
331 float t1 = 1 - d / 4; 340 value_t t1 = 1 - d / 4;
332 float t2 = t1 * t1; 341 value_t t2 = t1 * t1;
333 float t4 = t2 * t2; 342 value_t t4 = t2 * t2;
334 343
335 float o2 = o * o;
336
337 // (4t⁵ - 3t⁴) * (3o³ - 2o²) 344 // (4t⁵ - 3t⁴)
338 // alternative? ((o * 6 - 15) * o + 10) * o³ 345 value_t p = (4 * t1 - 3) * t4;
339 float p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
340 346
341 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;
342 const float *G = charges[h & 0xff]; 348 const value_t *G = charges3[h & 0xff];
343 349
344 v += dot (A, vec3d (G[0], G[1], G[2])) * p; 350 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
345 } 351 }
346 } 352 }
347 } 353 }
354 }
348 355
349 return clamp (v, -.9999999f, .9999999f); 356 return v * 2;
357}
358
359vec3d::T_numtype
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;
350} 416}
351 417
352template class noise_gen<vec2d>; 418template class noise_gen<vec2d>;
353template class noise_gen<vec3d>; 419template class noise_gen<vec3d>;
354 420
355///////////////////////////////////////////////////////////////////////////// 421/////////////////////////////////////////////////////////////////////////////
356 422
357template<class vec_t> 423template<class vec_t>
358static vec_t 424frac_gen<vec_t>::frac_gen (int octaves, value_t lacunarity, value_t hurst_expo, seed_t seed)
359ith_octave (vec_t P, int i) 425: octaves (octaves), lac (lacunarity), h (hurst_expo)
360{ 426{
361 vec_t r = P; 427 this->seed (seed);
362 r[0] += i;
363 return r;
364}
365 428
366template<class vec_t>
367frac_gen<vec_t>::frac_gen (value_t hurst_expo, value_t lacunarity)
368: h (hurst_expo), lac (lacunarity), noise_gen<vec_t> (0)
369{
370 value_t exsum = 0; 429 value_t exsum = 0;
430 value_t phi = noise (vec_t (value_t (0))) * 0.5 + 1;
371 431
372 for (int i = 0; i < MAX_OCTAVES; ++i) 432 for (int i = 0; i < octaves; ++i)
373 { 433 {
374 ex [i] = powf (lac, -h * i); 434 ex [i] = pow (lac, -h * i);
375 exsum += ex [i]; 435 exsum += ex [i];
376 fbm_mul [i] = 0.5f / (exsum * 0.75f); // .75f is a heuristic 436 fbm_mul [i] = 0.5 / (exsum * 0.75); // .75 is a heuristic
377 rot [i].set (0.4488f * i); 437 rot [i].set (phi * i + 1);
378 } 438 }
379} 439}
380 440
381template<class vec_t> 441template<class vec_t>
382typename frac_gen<vec_t>::value_t 442typename frac_gen<vec_t>::value_t
383frac_gen<vec_t>::fBm (vec_t P, int octaves) 443frac_gen<vec_t>::fBm (vec_t P)
384{ 444{
385 value_t v = 0.f; 445 value_t v = 0;
386 446
387 for (int i = 0; i < octaves; ++i) 447 for (int i = 0; i < octaves; ++i)
388 { 448 {
389 rot [i](P); 449 rot [i](P);
390 v += noise (ith_octave (P, i)) * ex [i]; 450 v += noise (P, i) * ex [i];
391 P *= lac; 451 P *= lac;
392 } 452 }
393 453
394 return clamp (v * fbm_mul [octaves - 1] + 0.5f, 0.f, .9999999f); 454 return v * fbm_mul [octaves - 1];
395} 455}
396 456
397template<class vec_t> 457template<class vec_t>
398typename frac_gen<vec_t>::value_t 458typename frac_gen<vec_t>::value_t
399frac_gen<vec_t>::turbulence (vec_t P, int octaves) 459frac_gen<vec_t>::turbulence (vec_t P)
400{ 460{
401 value_t v = 0.f; 461 value_t v = 0;
402 462
403 for (int i = 0; i < octaves; ++i) 463 for (int i = 0; i < octaves; ++i)
404 { 464 {
405 rot [i](P); 465 rot [i](P);
406 v += abs (noise (ith_octave (P, i))) * ex [i]; 466 v += abs (noise (P, i)) * ex [i];
407 P *= lac; 467 P *= lac;
408 } 468 }
409 469
410 return clamp (v * fbm_mul [octaves - 1] * 2.f, 0.f, .9999999f); 470 return v * fbm_mul [octaves - 1] * (0.5 / noise_gen<vec_t>::abs_avg ());
411} 471}
412 472
413template<class vec_t> 473template<class vec_t>
414typename frac_gen<vec_t>::value_t 474typename frac_gen<vec_t>::value_t
415frac_gen<vec_t>::multifractal (vec_t P, int octaves, value_t offset) 475frac_gen<vec_t>::multifractal (vec_t P, value_t offset)
416{ 476{
417 value_t v = 1.f; 477 value_t v = 1;
418 478
419 for (int i = 0; i < octaves; ++i) 479 for (int i = 0; i < octaves; ++i)
420 { 480 {
421 rot [i](P); 481 rot [i](P);
422 v *= noise (P) * ex [i] + offset; 482 v *= noise (P) * ex [i] + offset;
423 P *= lac; 483 P *= lac;
424 } 484 }
425 485
426 return clamp (v * 0.5f, 0.f, .9999999f); 486 return v * value_t (0.5);
427} 487}
428 488
429template<class vec_t> 489template<class vec_t>
430typename frac_gen<vec_t>::value_t 490typename frac_gen<vec_t>::value_t
431frac_gen<vec_t>::heterofractal (vec_t P, int octaves, value_t offset) 491frac_gen<vec_t>::heterofractal (vec_t P, value_t offset)
432{ 492{
433 value_t v = noise (P) + offset; 493 value_t v = noise (P) + offset;
434 int i;
435 494
436 for (i = 1; i < octaves; ++i) 495 for (int i = 1; i < octaves; ++i)
437 { 496 {
438 rot [i](P); 497 rot [i](P);
439 P *= lac; 498 P *= lac;
440 v += v * (noise (P) * ex [i] + offset); 499 v += v * (noise (P) * ex [i] + offset);
441 } 500 }
442 501
443 return v / powf (2., octaves); 502 return v / (1 << octaves);
444} 503}
445 504
446template<class vec_t> 505template<class vec_t>
447typename frac_gen<vec_t>::value_t 506typename frac_gen<vec_t>::value_t
448frac_gen<vec_t>::hybridfractal (vec_t P, int octaves, value_t offset, value_t gain) 507frac_gen<vec_t>::hybridfractal (vec_t P, value_t offset, value_t gain)
449{ 508{
450 value_t v = (noise (P) + offset) * ex [0]; 509 value_t v = (noise (P) + offset) * ex [0];
451 value_t weight = v; 510 value_t weight = v;
452 int i;
453 511
454 for (i = 1; i < octaves; ++i) 512 for (int i = 1; i < octaves; ++i)
455 { 513 {
456 rot [i](P); 514 rot [i](P);
457 P *= lac; 515 P *= lac;
458 516
459 min_it (weight, 1.f); 517 min_it (weight, 1);
460 518
461 value_t sig = (noise (P) + offset) * ex [i]; 519 value_t sig = (noise (P) + offset) * ex [i];
462 v += weight * sig; 520 v += weight * sig;
463 weight *= gain * sig; 521 weight *= gain * sig;
464 } 522 }
465 523
466 return clamp (v * 0.5f + 0.5f, 0.f, .9999999f); 524 return v * value_t (0.5) + value_t (0.5);
467} 525}
468 526
469template<class vec_t> 527template<class vec_t>
470typename frac_gen<vec_t>::value_t 528typename frac_gen<vec_t>::value_t
471frac_gen<vec_t>::ridgedmultifractal (vec_t P, int octaves, value_t offset, value_t gain) 529frac_gen<vec_t>::ridgedmultifractal (vec_t P, value_t offset, value_t gain)
472{ 530{
473 value_t sig = offset - abs (noise (P)); 531 value_t sig = offset - abs (noise (P));
474 sig *= sig; 532 sig *= sig;
475 value_t v = sig; 533 value_t v = sig;
476 534
477 for (int i = 1; i < octaves; ++i) 535 for (int i = 1; i < octaves; ++i)
478 { 536 {
479 rot [i](P); 537 rot [i](P);
480 P *= lac; 538 P *= lac;
481 539
540 // weight higher octaves by previous signal
482 value_t w = clamp (sig * gain, 0.f, 1.f); 541 value_t w = clamp (sig * gain, 0, 1);
483 542
484 sig = offset - abs (noise (P)); 543 sig = offset - abs (noise (P));
485 sig *= sig; 544 sig *= sig;
486 sig *= w; 545 sig *= w;
487 546
488 v += sig * ex [i]; 547 v += sig * ex [i];
489 } 548 }
490 549
491 return clamp (v * 0.25f, 0.f, .9999999f); 550 return v * value_t (0.25);
551}
552
553template<class vec_t>
554typename frac_gen<vec_t>::value_t
555frac_gen<vec_t>::billowfractal (vec_t P, value_t offset, value_t gain)
556{
557 value_t v = 0;
558
559 offset += 2 * noise_gen<vec_t>::abs_avg () - 1;
560
561 for (int i = 0; i < octaves; ++i)
562 {
563 rot [i](P);
564 v += (abs (noise (P, i)) * gain - offset) * ex [i];
565 P *= lac;
566 }
567
568 return v;
492} 569}
493 570
494// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2 571// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2
495template<class vec_t> 572template<class vec_t>
496typename frac_gen<vec_t>::value_t 573typename frac_gen<vec_t>::value_t
497frac_gen<vec_t>::terrain (vec_t P, int octaves) 574frac_gen<vec_t>::terrain (vec_t P)
498{ 575{
499 value_t v = 0.f; 576 value_t v = 0;
500 577
501 for (int i = 0; i < octaves; ++i) 578 for (int i = 0; i < octaves; ++i)
502 { 579 {
503 rot [i](P); 580 rot [i](P);
504 v += noise (P) * ex [i]; 581 v += noise (P) * ex [i];
505 P *= lac; 582 P *= lac;
506 } 583 }
507 584
508 v *= fbm_mul [octaves - 1]; 585 v *= fbm_mul [octaves - 1];
509 586
510 return v <= 0.f ? - powf (-v, 0.7f) : powf (v, 1. + noise (P) * v); 587 return v <= 0 ? - pow (-v, 0.7) : pow (v, 1 + noise (P) * v);
511} 588}
512 589
513template<class vec_t> 590template<class vec_t>
514typename frac_gen<vec_t>::value_t 591typename frac_gen<vec_t>::value_t
515frac_gen<vec_t>::terrain2 (vec_t P, int octaves) 592frac_gen<vec_t>::terrain2 (vec_t P)
516{ 593{
517 value_t a = fBm (P, octaves); 594 value_t a = fBm (P);
518 value_t b = ridgedmultifractal (P, octaves, 1, 8); 595 value_t b = ridgedmultifractal (P, 1, 8);
519 value_t fade = fBm (P + vec_t(10.3), octaves); 596 value_t fade = fBm (P + vec_t(10.3));
520 597
521 const value_t width = 0.05f; 598 const value_t width = 0.05;
522 599
523 if (fade > 0.5f + width) 600 if (fade > 0.5 + width)
524 return a; 601 return a;
525 else if (fade < 0.5f - width) 602 else if (fade < 0.5 - width)
526 return b; 603 return b;
527 604
528 fade = (fade - 0.5f + width) / (width * 2); 605 fade = (fade - 0.5 + width) / (width * 2);
529 606
530 // sigmoidal curve 607 // sigmoidal curve
531 fade = fade * fade * 2 * (1.5f - fade); 608 fade = fade * fade * 2 * (1.5 - fade);
532 609
533 return a * fade + b * (1 - fade); 610 return a * fade + b * (1 - fade);
534} 611}
535 612
536template class frac_gen<vec2d>; 613template class frac_gen<vec2d>;
537template class frac_gen<vec3d>; 614template class frac_gen<vec3d>;
538 615
539/////////////////////////////////////////////////////////////////////////////
540
541#if 0
542void hack(); void hack()
543{
544 frac_gen<vec2d> gen (0.5, 2);
545 frac_gen<vec3d> gen3;
546
547#if 0
548 int N = 1024;
549
550 printf ("P5 %d %d 255\n", N, N);
551 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
552 for (int y = 0; y < N; ++y)
553 {
554 if (!(y&63))fprintf (stderr, "y %d\n", y);//D
555 for (int x = 0; x < N; ++x)
556 {
557 //putc (127 * n.noise (x * 0.1, y * 0.1, 0, 0,0,1) + 128, stdout);
558 //putc (256 * gen.terrain2 (x * 0.004, y * 0.004, 8), stdout);
559 //putc (256 * gen.fBm (x * 0.01, y * 0.01, 3), stdout);
560 //putc (256 * gen.turbulence (x * 0.004 - 1, y * 0.004 - 1, 8), stdout);
561 //putc (256 * gen.heterofractal (x * 0.008, y * 0.008, 8, 0.9), stdout);
562
563 // mountais or somesuch(?)
564 //putc (256 * gen.hybridfractal (x * 0.01, y * 0.01, 8, -.4, -4), stdout);
565
566 // temperature
567 //putc (256 * gen.fBm (x * 0.002, y * 0.002, 2), stdout);
568 // rain
569 //putc (256 * gen.ridgedmultifractal (x * 0.01, y * 0.01, 3, 1.03, 2), stdout);
570 }
571 }
572#else
573 int N = 512;
574
575 //printf ("P6 %d %d 255\n", N, N);
576 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
577 for (int z = 0; z < N; ++z)
578 {
579 if (!(z&7))fprintf (stderr, "z %d\n", z);//D
580 for (int y = 0; y < N; ++y)
581 for (int x = 0; x < N; ++x)
582 {
583 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;
584
585#if 0
586 if (z < 64)
587 v = v * (z * z) / (64 * 64);
588#endif
589
590 if (v <= 0.9999)
591 continue;
592
593 float r[4];
594 int i[4];
595
596 r[0] = x;
597 r[1] = y;
598 r[2] = z;
599 r[3] = v;
600
601 memcpy (i, r, 16);
602
603 i[0] = htonl (i[0]);
604 i[1] = htonl (i[1]);
605 i[2] = htonl (i[2]);
606 i[3] = htonl (i[3]);
607
608 fwrite (i, 4*4, 1, stdout);
609 }
610 }
611#endif
612
613 exit (0);
614}
615#endif

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