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Comparing deliantra/server/common/noise.C (file contents):
Revision 1.7 by root, Sat Apr 23 06:35:55 2011 UTC vs.
Revision 1.13 by root, Sat Apr 30 05:41:17 2011 UTC

… …
22 22
23#include "noise.h" 23#include "noise.h"
24 24
25///////////////////////////////////////////////////////////////////////////// 25/////////////////////////////////////////////////////////////////////////////
26 26
27// perl -e 'for(0..255) { $p = (atan2 1,0) / 64 * $_; printf " %10g, %10g,\n", sin $p, cos $p }' | sort -R
28static const float charges2[256][2] = {
29 -.975702, -.219101, .893224, .449611, .870087, -.492898, .595699, -.803208,
30 .14673, .989177, .995185, .0980171, .91421, -.405241, -.514103, .857729,
31 -.985278, -.170962, -.689541, -.724247, -.427555, .903989, .83147, -.55557,
32 .999699, -.0245412, .634393, .77301, -.514103, -.857729, -.0735646, -.99729,
33 .514103, -.857729, -.595699, -.803208, -.290285, .95694, .595699, .803208,
34 .266713, .963776, -.33689, .941544, .492898, -.870087, -.471397, -.881921,
35 -.99729, -.0735646, .615232, -.788346, -.91421, -.405241, -.575808, .817585,
36 .0980171, .995185, -.980785, .19509, -.122411, -.99248, .0735646, .99729,
37 -.634393, .77301, -.91421, .405241, .99248, .122411, .903989, -.427555,
38 -.24298, .970031, -.857729, .514103, -.359895, .932993, .382683, .92388,
39 .740951, -.671559, -.893224, .449611, -.95694, -.290285, -.975702, .219101,
40 -.970031, .24298, .999699, .0245412, -.405241, .91421, .985278, .170962,
41 .382683, -.92388, .95694, -.290285, .707107, -.707107, -.817585, -.575808,
42 -.989177, .14673, -.19509, -.980785, -.359895, -.932993, .313682, .949528,
43 -.0980171, .995185, 1, 6.12323e-17, .963776, -.266713, .998795, -.0490677,
44 -.998795, -.0490677, -.970031, -.24298, -.55557, .83147, -.14673, .989177,
45 -.83147, -.55557, -.995185, -.0980171, .870087, .492898, .941544, -.33689,
46 .575808, -.817585, .33689, .941544, .19509, -.980785, 0, 1,
47 .219101, -.975702, -.83147, .55557, .757209, -.653173, -.95694, .290285,
48 -.266713, .963776, -.0490677, .998795, .405241, .91421, -.405241, -.91421,
49 -.689541, .724247, -.534998, -.844854, -.99248, -.122411, .724247, .689541,
50 .492898, .870087, .817585, -.575808, .740951, .671559, -.33689, -.941544,
51 .95694, .290285, .77301, -.634393, .0245412, -.999699, -.77301, -.634393,
52 -.382683, .92388, -.24298, -.970031, -.893224, -.449611, .449611, .893224,
53 .975702, -.219101, -.382683, -.92388, .844854, .534998, -.803208, -.595699,
54 .941544, .33689, .963776, .266713, .932993, .359895, -.0735646, .99729,
55 .634393, -.77301, .405241, -.91421, .33689, -.941544, .99729, .0735646,
56 1.22465e-16, -1, -.941544, -.33689, .0490677, -.998795, -.313682, .949528,
57 .92388, .382683, -.999699, .0245412, .0245412, .999699, .653173, .757209,
58 -.803208, .595699, .980785, -.19509, .817585, .575808, .975702, .219101,
59 -.615232, -.788346, .99248, -.122411, .998795, .0490677, -.707107, .707107,
60 .803208, -.595699, .671559, .740951, -.757209, -.653173, -.949528, .313682,
61 -.989177, -.14673, -.817585, .575808, -.14673, -.989177, -1, -1.83697e-16,
62 .290285, .95694, -.932993, -.359895, .24298, -.970031, .170962, .985278,
63 -.671559, -.740951, .427555, .903989, .427555, -.903989, -.941544, .33689,
64 -.492898, -.870087, -.266713, -.963776, .857729, -.514103, -.724247, .689541,
65 .724247, -.689541, -.653173, .757209, .689541, -.724247, .949528, -.313682,
66 -.19509, .980785, -.740951, .671559, -.999699, -.0245412, .689541, .724247,
67 .803208, .595699, -.170962, .985278, .0735646, -.99729, .970031, -.24298,
68 -.170962, -.985278, .471397, .881921, .91421, .405241, .893224, -.449611,
69 .0490677, .998795, -.615232, .788346, -.998795, .0490677, -.427555, -.903989,
70 -.0245412, .999699, -.534998, .844854, -.313682, -.949528, -.55557, -.83147,
71 -.903989, -.427555, -.724247, -.689541, -.740951, -.671559, .985278, -.170962,
72 -.857729, -.514103, -.99729, .0735646, .881921, -.471397, .534998, .844854,
73 .359895, -.932993, .77301, .634393, .99729, -.0735646, .290285, -.95694,
74 .575808, .817585, .757209, .653173, .903989, .427555, -.995185, .0980171,
75 -.903989, .427555, -.844854, .534998, -.707107, -.707107, -.92388, .382683,
76 -.653173, -.757209, -.881921, -.471397, -.219101, .975702, -.595699, .803208,
77 .0980171, -.995185, -.788346, .615232, -.0980171, -.995185, -.985278, .170962,
78 .122411, .99248, -.449611, -.893224, .170962, -.985278, .788346, .615232,
79 -.492898, .870087, .671559, -.740951, .449611, -.893224, -.757209, .653173,
80 .83147, .55557, -.290285, -.95694, -.932993, .359895, -.870087, -.492898,
81 .266713, -.963776, -.881921, .471397, -.77301, .634393, -.471397, .881921,
82 .844854, -.534998, .707107, .707107, .534998, -.844854, .514103, .857729,
83 .14673, -.989177, .980785, .19509, -.122411, .99248, -.449611, .893224,
84 .995185, -.0980171, -.634393, -.77301, .857729, .514103, .55557, .83147,
85 -.92388, -.382683, -.844854, -.534998, -.963776, .266713, .989177, -.14673,
86 .313682, -.949528, .359895, .932993, .24298, .970031, -.949528, -.313682,
87 .932993, -.359895, .55557, -.83147, .615232, .788346, -.788346, -.615232,
88 -.0245412, -.999699, -.219101, -.975702, .788346, -.615232, -.99248, .122411,
89 -.671559, .740951, -.870087, .492898, .970031, .24298, .881921, .471397,
90 .122411, -.99248, .471397, -.881921, .19509, .980785, -.963776, -.266713,
91 .92388, -.382683, .989177, .14673, -.575808, -.817585, .219101, .975702,
92 -.0490677, -.998795, -.980785, -.19509, .949528, .313682, .653173, -.757209,
93};
94
27// http://www-wales.ch.cam.ac.uk/~wales/CCD/Thomson/table.html, random permutation 95// http://www-wales.ch.cam.ac.uk/~wales/CCD/Thomson/table.html, random permutation
28// used as gradient vectors for noise3d 96// used as gradient vectors for noise3d
29static const float charges[256][3] = { 97static const float charges3[256][3] = {
30 6.32096444e-01, -6.11406706e-01, 4.76062943e-01, 5.19172442e-01, 8.08229585e-01, -2.77893708e-01, 98 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, 99 -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, 100 -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, 101 -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, 102 -6.86776297e-01, 5.34610386e-01, -4.92473403e-01, -8.45541961e-01, -2.41708225e-01, 4.76062943e-01,
… …
158}; 226};
159 227
160///////////////////////////////////////////////////////////////////////////// 228/////////////////////////////////////////////////////////////////////////////
161 229
162template<int N, typename T> 230template<int N, typename T>
163template<class random_generator>
164void 231void
165permutation<N,T>::seed (random_generator &rng) 232permutation<N,T>::seed (seedable_rand_gen &rng)
166{ 233{
167 for (int i = 0; i < N; ++i) 234 for (int i = 0; i < N; ++i)
168 pmap[i] = i; 235 pmap[i] = i;
169 236
170 // fisher-yates to randomly perturb 237 // fisher-yates to randomly perturb
… …
174 241
175template class permutation<256, uint8_t>; 242template class permutation<256, uint8_t>;
176 243
177///////////////////////////////////////////////////////////////////////////// 244/////////////////////////////////////////////////////////////////////////////
178 245
179static vec2d 246template<class vec_t>
180floor (vec2d v) 247void
248noise_gen_base<vec_t>::seed (seedable_rand_gen &rng)
181{ 249{
182 return vec2d (std::floor (v[0]), std::floor (v[1])); 250 for (int i = 0; i < array_length (rvmap); ++i)
251 rvmap[i].seed (rng);
183} 252}
184 253
185static vec3d 254template<class vec_t>
186floor (vec3d v) 255void
187{ 256noise_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{ 257{
193 seedable_rand_gen rng (seed); 258 seedable_rand_gen rng (seed);
194 259
195#if 0 260 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} 261}
229 262
263template<>
230vec2d::T_numtype 264vec2d::T_numtype
231noise_gen<vec2d>::operator() (vec2d P) 265noise_gen_base<vec2d>::operator() (vec2d P, uint32_t seed)
232{ 266{
233 vec2d I = floor (P); 267 vec2d I = floor (P);
234 vec2d F = P - I; 268 vec2d F = P - I;
235 269
236 float v = 0; 270 value_t v = 0;
271
272 uint8_t i1 = uint8_t (I[1]) ^ (seed >> 16);
273 uint8_t i0 = uint8_t (I[0]) ^ (seed >> 8);
237 274
238 for (int j = -1; j <= 2; ++j) 275 for (int j = -1; j <= 2; ++j)
276 {
277 uint8_t h1 = rvmap[1](i1 + j) ^ seed;
278
239 for (int i = -1; i <= 2; ++i) 279 for (int i = -1; i <= 2; ++i)
240 { 280 {
241 vec2d A = F - vec2d (i, j); 281 vec2d A = F - vec2d (i, j);
242
243 float d = dot (A, A); 282 value_t d = dot (A, A);
244 283
245 if (d < 4) 284 if (d < 4)
246 { 285 {
247 float t1 = 1 - d / 4; 286 value_t t1 = 1 - d / 4;
248 float t2 = t1 * t1; 287 value_t t2 = t1 * t1;
249 float t4 = t2 * t2; 288 value_t t4 = t2 * t2;
250 289
251 float p = (4 * t1 - 3) * t4; 290 value_t p = (4 * t1 - 3) * t4;
252 291
253 int h = rvmap [0](I[0] + i) ^ rvmap [1](I[1] + j); 292 uint8_t h = rvmap[0](i0 + i) ^ h1;
254 vec2d G = rvec [h & 0xff]; 293 vec2d G = charges2[h & 0xff];
255 294
256 v += dot (A, G) * p; 295 v += dot (A, G) * p;
257 } 296 }
258 } 297 }
298 }
259 299
260 return clamp (v, -.9999999f, .9999999f); 300 return v;
261} 301}
262 302
263///////////////////////////////////////////////////////////////////////////// 303/////////////////////////////////////////////////////////////////////////////
264 304
265noise_gen<vec3d>::noise_gen (uint32_t seed) 305template<>
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 306vec3d::T_numtype
275noise_gen<vec3d>::operator() (vec3d P) 307noise_gen_base<vec3d>::operator() (vec3d P, uint32_t seed)
276{ 308{
277 vec3d I = floor (P); 309 vec3d I = floor (P);
278 vec3d F = P - I; 310 vec3d F = P - I;
279 311
280 float v = 0; 312 uint8_t i2 = uint8_t (I[2]) ^ (seed >> 24);
313 uint8_t i1 = uint8_t (I[1]) ^ (seed >> 16);
314 uint8_t i0 = uint8_t (I[0]) ^ (seed >> 8);
281 315
282 for (int j = -1; j <= 2; ++j) 316 value_t v = 0;
283 for (int i = -1; i <= 2; ++i) 317
284 for (int k = -1; k <= 2; ++k) 318 for (int k = -1; k <= 2; ++k)
319 {
320 uint8_t h2 = rvmap[2](i2 + k) ^ seed;
321
322 for (int j = -1; j <= 2; ++j)
285 { 323 {
286 vec3d A = F - vec3d (i, j, k); 324 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
287 float d = dot (A, A);
288 325
289 if (d < 4) 326 for (int i = -1; i <= 2; ++i)
290 { 327 {
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); 328 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); 329 value_t d = dot (A, A);
328 330
329 if (d < 4) 331 if (d < 4)
330 { 332 {
331 float t1 = 1 - d / 4; 333 value_t t1 = 1 - d / 4;
332 float t2 = t1 * t1; 334 value_t t2 = t1 * t1;
333 float t4 = t2 * t2; 335 value_t t4 = t2 * t2;
334 336
335 float o2 = o * o;
336
337 // (4t⁵ - 3t⁴) * (3o³ - 2o²) 337 // (4t⁵ - 3t⁴)
338 // alternative? ((o * 6 - 15) * o + 10) * o³ 338 value_t p = (4 * t1 - 3) * t4;
339 float p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
340 339
341 int h = rvmap[0](I[0] + i) ^ rvmap[1](I[1] + j) ^ rvmap[2](I[2] + k); 340 uint8_t h = rvmap[0](i0 + i) ^ h1;
342 const float *G = charges[h & 0xff]; 341 const value_t *G = charges3[h & 0xff];
343 342
344 v += dot (A, vec3d (G[0], G[1], G[2])) * p; 343 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
345 } 344 }
346 } 345 }
347 } 346 }
347 }
348 348
349 return clamp (v, -.9999999f, .9999999f); 349 return v * 2;
350}
351
352vec3d::T_numtype
353noise_gen<vec3d>::operator() (vec3d P, vec3d N, uint32_t seed)
354{
355 vec3d I = floor (P);
356 vec3d F = P - I;
357
358 uint8_t i2 = uint8_t (I[2]) ^ (seed >> 24);
359 uint8_t i1 = uint8_t (I[1]) ^ (seed >> 16);
360 uint8_t i0 = uint8_t (I[0]) ^ (seed >> 8);
361
362 value_t v = 0;
363
364 for (int k = -1; k <= 2; ++k)
365 {
366 uint8_t h2 = rvmap[2](i2 + k) ^ seed;
367
368 for (int j = -1; j <= 2; ++j)
369 {
370 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
371
372 for (int i = -1; i <= 2; ++i)
373 {
374 vec3d D = F - vec3d (i, j, k);
375 value_t e = dot (D, N);
376 value_t o = 1 - abs (e);
377
378 if (o > 0)
379 {
380 vec3d A = D - e * N;
381 value_t d = dot (A, A);
382
383 if (d < 4)
384 {
385 value_t t1 = 1 - d / 4;
386 value_t t2 = t1 * t1;
387 value_t t4 = t2 * t2;
388
389 value_t o2 = o * o;
390
391 // (4t⁵ - 3t⁴) * (3o³ - 2o²)
392 // alternative? ((o * 6 - 15) * o + 10) * o³
393 value_t p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
394
395 uint8_t h = rvmap[0](i0 + i) ^ h1;
396 const value_t *G = charges3[h & 0xff];
397
398 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
399 }
400 }
401 }
402 }
403 }
404
405 return v;
350} 406}
351 407
352template class noise_gen<vec2d>; 408template class noise_gen<vec2d>;
353template class noise_gen<vec3d>; 409template class noise_gen<vec3d>;
354 410
355///////////////////////////////////////////////////////////////////////////// 411/////////////////////////////////////////////////////////////////////////////
356 412
357template<class vec_t> 413template<class vec_t>
358static vec_t 414frac_gen<vec_t>::frac_gen (int octaves, value_t lacunarity, value_t hurst_expo, seed_t seed)
359ith_octave (vec_t P, int i) 415: octaves (octaves), lac (lacunarity), h (hurst_expo)
360{ 416{
361 vec_t r = P; 417 this->seed (seed);
362 r[0] += i;
363 return r;
364}
365 418
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; 419 value_t exsum = 0;
420 value_t phi = noise (vec_t (value_t (0))) * 0.5 + 1;
371 421
372 for (int i = 0; i < MAX_OCTAVES; ++i) 422 for (int i = 0; i < octaves; ++i)
373 { 423 {
374 ex [i] = powf (lac, -h * i); 424 ex [i] = pow (lac, -h * i);
375 exsum += ex [i]; 425 exsum += ex [i];
376 fbm_mul [i] = 0.5f / (exsum * 0.75f); // .75f is a heuristic 426 fbm_mul [i] = 0.5 / (exsum * 0.75); // .75 is a heuristic
377 rot [i].set (0.4488f * i); 427 rot [i].set (phi * i + 1);
378 } 428 }
379} 429}
380 430
381template<class vec_t> 431template<class vec_t>
382typename frac_gen<vec_t>::value_t 432typename frac_gen<vec_t>::value_t
383frac_gen<vec_t>::fBm (vec_t P, int octaves) 433frac_gen<vec_t>::fBm (vec_t P)
384{ 434{
385 value_t v = 0.f; 435 value_t v = 0;
386 436
387 for (int i = 0; i < octaves; ++i) 437 for (int i = 0; i < octaves; ++i)
388 { 438 {
389 rot [i](P); 439 rot [i](P);
390 v += noise (ith_octave (P, i)) * ex [i]; 440 v += noise (P, i) * ex [i];
391 P *= lac; 441 P *= lac;
392 } 442 }
393 443
394 return clamp (v * fbm_mul [octaves - 1] + 0.5f, 0.f, .9999999f); 444 return v * fbm_mul [octaves - 1];
395} 445}
396 446
397template<class vec_t> 447template<class vec_t>
398typename frac_gen<vec_t>::value_t 448typename frac_gen<vec_t>::value_t
399frac_gen<vec_t>::turbulence (vec_t P, int octaves) 449frac_gen<vec_t>::turbulence (vec_t P)
400{ 450{
401 value_t v = 0.f; 451 value_t v = 0;
402 452
403 for (int i = 0; i < octaves; ++i) 453 for (int i = 0; i < octaves; ++i)
404 { 454 {
405 rot [i](P); 455 rot [i](P);
406 v += abs (noise (ith_octave (P, i))) * ex [i]; 456 v += abs (noise (P, i)) * ex [i];
407 P *= lac; 457 P *= lac;
408 } 458 }
409 459
410 return clamp (v * fbm_mul [octaves - 1] * 2.f, 0.f, .9999999f); 460 return v * fbm_mul [octaves - 1] * (0.5 / noise_gen<vec_t>::abs_avg ());
411} 461}
412 462
413template<class vec_t> 463template<class vec_t>
414typename frac_gen<vec_t>::value_t 464typename frac_gen<vec_t>::value_t
415frac_gen<vec_t>::multifractal (vec_t P, int octaves, value_t offset) 465frac_gen<vec_t>::multifractal (vec_t P, value_t offset)
416{ 466{
417 value_t v = 1.f; 467 value_t v = 1;
418 468
419 for (int i = 0; i < octaves; ++i) 469 for (int i = 0; i < octaves; ++i)
420 { 470 {
421 rot [i](P); 471 rot [i](P);
422 v *= noise (P) * ex [i] + offset; 472 v *= noise (P) * ex [i] + offset;
423 P *= lac; 473 P *= lac;
424 } 474 }
425 475
426 return clamp (v * 0.5f, 0.f, .9999999f); 476 return v * value_t (0.5);
427} 477}
428 478
429template<class vec_t> 479template<class vec_t>
430typename frac_gen<vec_t>::value_t 480typename frac_gen<vec_t>::value_t
431frac_gen<vec_t>::heterofractal (vec_t P, int octaves, value_t offset) 481frac_gen<vec_t>::heterofractal (vec_t P, value_t offset)
432{ 482{
433 value_t v = noise (P) + offset; 483 value_t v = noise (P) + offset;
434 int i;
435 484
436 for (i = 1; i < octaves; ++i) 485 for (int i = 1; i < octaves; ++i)
437 { 486 {
438 rot [i](P); 487 rot [i](P);
439 P *= lac; 488 P *= lac;
440 v += v * (noise (P) * ex [i] + offset); 489 v += v * (noise (P) * ex [i] + offset);
441 } 490 }
442 491
443 return v / powf (2., octaves); 492 return v / (1 << octaves);
444} 493}
445 494
446template<class vec_t> 495template<class vec_t>
447typename frac_gen<vec_t>::value_t 496typename frac_gen<vec_t>::value_t
448frac_gen<vec_t>::hybridfractal (vec_t P, int octaves, value_t offset, value_t gain) 497frac_gen<vec_t>::hybridfractal (vec_t P, value_t offset, value_t gain)
449{ 498{
450 value_t v = (noise (P) + offset) * ex [0]; 499 value_t v = (noise (P) + offset) * ex [0];
451 value_t weight = v; 500 value_t weight = v;
452 int i;
453 501
454 for (i = 1; i < octaves; ++i) 502 for (int i = 1; i < octaves; ++i)
455 { 503 {
456 rot [i](P); 504 rot [i](P);
457 P *= lac; 505 P *= lac;
458 506
459 min_it (weight, 1.f); 507 min_it (weight, 1);
460 508
461 value_t sig = (noise (P) + offset) * ex [i]; 509 value_t sig = (noise (P) + offset) * ex [i];
462 v += weight * sig; 510 v += weight * sig;
463 weight *= gain * sig; 511 weight *= gain * sig;
464 } 512 }
465 513
466 return clamp (v * 0.5f + 0.5f, 0.f, .9999999f); 514 return v * value_t (0.5) + value_t (0.5);
467} 515}
468 516
469template<class vec_t> 517template<class vec_t>
470typename frac_gen<vec_t>::value_t 518typename frac_gen<vec_t>::value_t
471frac_gen<vec_t>::ridgedmultifractal (vec_t P, int octaves, value_t offset, value_t gain) 519frac_gen<vec_t>::ridgedmultifractal (vec_t P, value_t offset, value_t gain)
472{ 520{
473 value_t sig = offset - abs (noise (P)); 521 value_t sig = offset - abs (noise (P));
474 sig *= sig; 522 sig *= sig;
475 value_t v = sig; 523 value_t v = sig;
476 524
477 for (int i = 1; i < octaves; ++i) 525 for (int i = 1; i < octaves; ++i)
478 { 526 {
479 rot [i](P); 527 rot [i](P);
480 P *= lac; 528 P *= lac;
481 529
530 // weight higher octaves by previous signal
482 value_t w = clamp (sig * gain, 0.f, 1.f); 531 value_t w = clamp (sig * gain, 0, 1);
483 532
484 sig = offset - abs (noise (P)); 533 sig = offset - abs (noise (P));
485 sig *= sig; 534 sig *= sig;
486 sig *= w; 535 sig *= w;
487 536
488 v += sig * ex [i]; 537 v += sig * ex [i];
489 } 538 }
490 539
491 return clamp (v * 0.25f, 0.f, .9999999f); 540 return v * value_t (0.25);
541}
542
543template<class vec_t>
544typename frac_gen<vec_t>::value_t
545frac_gen<vec_t>::billowfractal (vec_t P, value_t offset, value_t gain)
546{
547 value_t v = 0;
548
549 offset += 2 * noise_gen<vec_t>::abs_avg () - 1;
550
551 for (int i = 0; i < octaves; ++i)
552 {
553 rot [i](P);
554 v += (abs (noise (P, i)) * gain - offset) * ex [i];
555 P *= lac;
556 }
557
558 return v;
492} 559}
493 560
494// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2 561// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2
495template<class vec_t> 562template<class vec_t>
496typename frac_gen<vec_t>::value_t 563typename frac_gen<vec_t>::value_t
497frac_gen<vec_t>::terrain (vec_t P, int octaves) 564frac_gen<vec_t>::terrain (vec_t P)
498{ 565{
499 value_t v = 0.f; 566 value_t v = 0;
500 567
501 for (int i = 0; i < octaves; ++i) 568 for (int i = 0; i < octaves; ++i)
502 { 569 {
503 rot [i](P); 570 rot [i](P);
504 v += noise (P) * ex [i]; 571 v += noise (P) * ex [i];
505 P *= lac; 572 P *= lac;
506 } 573 }
507 574
508 v *= fbm_mul [octaves - 1]; 575 v *= fbm_mul [octaves - 1];
509 576
510 return v <= 0.f ? - powf (-v, 0.7f) : powf (v, 1. + noise (P) * v); 577 return v <= 0 ? - pow (-v, 0.7) : pow (v, 1 + noise (P) * v);
511} 578}
512 579
513template<class vec_t> 580template<class vec_t>
514typename frac_gen<vec_t>::value_t 581typename frac_gen<vec_t>::value_t
515frac_gen<vec_t>::terrain2 (vec_t P, int octaves) 582frac_gen<vec_t>::terrain2 (vec_t P)
516{ 583{
517 value_t a = fBm (P, octaves); 584 value_t a = fBm (P);
518 value_t b = ridgedmultifractal (P, octaves, 1, 8); 585 value_t b = ridgedmultifractal (P, 1, 8);
519 value_t fade = fBm (P + vec_t(10.3), octaves); 586 value_t fade = fBm (P + vec_t(10.3));
520 587
521 const value_t width = 0.05f; 588 const value_t width = 0.05;
522 589
523 if (fade > 0.5f + width) 590 if (fade > 0.5 + width)
524 return a; 591 return a;
525 else if (fade < 0.5f - width) 592 else if (fade < 0.5 - width)
526 return b; 593 return b;
527 594
528 fade = (fade - 0.5f + width) / (width * 2); 595 fade = (fade - 0.5 + width) / (width * 2);
529 596
530 // sigmoidal curve 597 // sigmoidal curve
531 fade = fade * fade * 2 * (1.5f - fade); 598 fade = fade * fade * 2 * (1.5 - fade);
532 599
533 return a * fade + b * (1 - fade); 600 return a * fade + b * (1 - fade);
534} 601}
535 602
536template class frac_gen<vec2d>; 603template class frac_gen<vec2d>;
… …
539///////////////////////////////////////////////////////////////////////////// 606/////////////////////////////////////////////////////////////////////////////
540 607
541void noise_test (); 608void noise_test ();
542void noise_test () 609void noise_test ()
543{ 610{
544 frac_gen<vec2d> gen (0.5, 1.9); 611 frac2d gen;
545 frac_gen<vec3d> gen3; 612
613 frac2d vec_gen1 (4, 2, 0.5, 1);
614 frac2d vec_gen2 (4, 2, 0.5, 2);
546 615
547#if 1 616#if 1
548 int N = 1024; 617 int N = 1024;
549 618
550 printf ("P5 %d %d 255\n", N, N); 619 printf ("P6 %d %d 255\n", N, N);
551 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm 620 // 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) 621 for (int y = 0; y < N; ++y)
553 { 622 {
554 if (!(y&63))fprintf (stderr, "y %d\n", y);//D 623 if (!(y&63))fprintf (stderr, "y %d\n", y);//D
555 for (int x = 0; x < N; ++x) 624 for (int x = 0; x < N; ++x)
556 { 625 {
626 vec2d P = vec2d (x, y) * (25000.f / N);
627
557 //putc (127 * n.noise (x * 0.1, y * 0.1, 0, 0,0,1) + 128, stdout); 628 //putc (127 * gen.noise (vec2d (x * 0.01, y * 0.01)) + 128, stdout);
558 //putc (256 * gen.terrain2 (x * 0.004, y * 0.004, 8), stdout); 629 //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); 630 //putc (256 * gen.fBm (vec2d(x * 0.01, y * 0.01), 16), stdout);
560 putc (256 * gen.turbulence (vec2d (x * 0.004 - 1, y * 0.004 - 1), 8), stdout); 631 //putc (256 * gen.turbulence (vec2d (x * 0.004 - 1, y * 0.004 - 1), 10), stdout);
561 //putc (256 * gen.heterofractal (x * 0.008, y * 0.008, 8, 0.9), stdout); 632 //putc (256 * gen.heterofractal (vec2d (x * 0.008, y * 0.008), 8, 0.9), stdout);
562 633
563 // mountais or somesuch(?) 634 // mountais or somesuch(?)
564 //putc (256 * gen.hybridfractal (x * 0.01, y * 0.01, 8, -.4, -4), stdout); 635 //putc (256 * gen.hybridfractal (vec2d (x * 0.01, y * 0.01), 8, -.4, -4), stdout);
565 636
566 // temperature 637 // temperature
567 //putc (256 * gen.fBm (x * 0.002, y * 0.002, 2), stdout); 638 //putc (256 * gen.fBm (vec2d (x * 0.002, y * 0.002), 2), stdout);
568 // rain 639 // rain
569 640
641 float continent;
642
643 {
644 const float continent_scale = 0.00008;
645
646 vec2d perturb (
647 vec_gen1.fBm (P * 0.0004),
648 vec_gen2.fBm (P * 0.0004)
649 );
650
651 const float W = 1000 * continent_scale;
652 const float N = (25000 - 1) * continent_scale;
653
654 static frac2d perturb_gen (4, 2, 0.5, 3);
655 float perturb_perturb = gen.fBm (P * 0.0004);
656 perturb_perturb = perturb_perturb * perturb_perturb * 0.004;
657
658 vec2d P_perturb = P * continent_scale + perturb * min (W, gen.noise (P * perturb_perturb) * W * 8);
659
660 static frac2d continent_gen (13, 2.13, 0.5);
661 continent = continent_gen.fBm (P_perturb) + 0.05f;
662
663 float border = W; // within n places of the border
664
665 min_it (border, P_perturb [0]);
666 min_it (border, N - P_perturb [0]);
667 min_it (border, P_perturb [1]);
668 min_it (border, N - P_perturb [1]);
669
670 continent = blend (-1.f, continent, border, 0.f, W);
671 }
672
673 vec3d c (1, 1, 1);
674 float v;
675
676 if (continent < 0)
677 {
678 // ocean
679
680 v = min (continent * 10, -0.2f);
681 c = vec3d (0, 0, 1);
682 }
683 else
684 {
685 // continent
686
687 // big rivers
688 static frac2d river_gen (2);
689 float river1 = river_gen.fBm (P * 0.0004);// - (P[0] / 25000) * 0.18 + 0.06;
690 float river2 = river_gen.ridgedmultifractal (P * 0.04 + vec2d (3, 5), 0.8, 10) - (P[1] / 25000) * 0.1;
691
692 if (river1 > 0.05f)
693 {
694 v = -0.1f;
695 c = vec3d (0.4, 0.4, 1);
696 }
697 else if (river1 > 0.08f && river2 > 0.1f)
698 {
699 v = -0.05f;
700 c = vec3d (0.4, 0.4, 1);
701 }
702 else
703 {
704 river1 -= 0.07f;
705
706 //c = river1 > 0 ? vec3d (0.8, 0.8, 0) : vec3d (0.8, 0, 0);
707 c = blend0 (vec3d (0.8, 0, 0), vec3d (0.8, 0.8, 0), river1, 0.01f);;
708
709 static frac2d mountain_gen (8, 2.14, 0.5);
710 float mountain = mountain_gen.ridgedmultifractal (P * 0.004);
711 v = blend0 (mountain * 3 - 1, continent, river1, 0.05f);
712 }
713
714 v=abs(river1) < 0.1;
715 c=vec3d(1,1,1);
716 }
717
718 c *= v * 0.5 + 0.5;
719
720 putc (clamp<int> (255 * c[0], 0, 255), stdout);
721 putc (clamp<int> (255 * c[1], 0, 255), stdout);
722 putc (clamp<int> (255 * c[2], 0, 255), stdout);
723
570 //cells 724 //cells
571 //putc (256 * gen.ridgedmultifractal (vec2d (x * 0.01, y * 0.01), 3, 0.5 + gen.noise(vec2d(x*0.01,y*0.01)), 2), stdout); 725 //putc (127.49 * gen.billowfractal (vec2d (x * 0.01, y * 0.01), 9) + 128, stdout);
572 } 726 }
573 } 727 }
574#else 728#else
575 int N = 512; 729 int N = 128;
576 730
577 //printf ("P6 %d %d 255\n", N, N); 731 //printf ("P6 %d %d 255\n", N, N);
578 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm 732 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
733 frac3d gen3 (3);;
579 for (int z = 0; z < N; ++z) 734 for (int z = 0; z < N; ++z)
580 { 735 {
581 if (!(z&7))fprintf (stderr, "z %d\n", z);//D 736 if (!(z&7))fprintf (stderr, "z %d\n", z);//D
582 for (int y = 0; y < N; ++y) 737 for (int y = 0; y < N; ++y)
583 for (int x = 0; x < N; ++x) 738 for (int x = 0; x < N; ++x)
584 { 739 {
585 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; 740 float v = gen3.ridgedmultifractal (vec3d (x * 0.001 + 0.2, y * 0.001 + 0.2, z * 0.01 + 0.2), 1.03, 2) * 2;
586 741
587#if 0 742#if 0
588 if (z < 64) 743 if (z < 64)
589 v = v * (z * z) / (64 * 64); 744 v = v * (z * z) / (64 * 64);
590#endif 745#endif
591 746
592 if (v <= 0.9999) 747 if (v <= 0.9)
593 continue; 748 continue;
594 749
595 float r[4]; 750 float r[4];
596 int i[4]; 751 int i[4];
597 752

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