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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 1.15 by root, Sat Apr 30 11:03:46 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
96// used as gradient vectors for noise3d
28static const float charges[256][3] = { 97static const float charges3[256][3] = {
29 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,
30 -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,
31 -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,
32 -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,
33 -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,
154 4.98855035e-01, -3.98703643e-01, 7.69531714e-01, 2.55373649e-01, -7.56251592e-02, 9.63880249e-01, 223 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, 224 -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, 225 -3.07350590e-01, -9.14677987e-01, 2.62487703e-01, 5.60298616e-01, 1.74821302e-01, 8.09631381e-01,
157}; 226};
158 227
159static vec2d 228/////////////////////////////////////////////////////////////////////////////
160floor (vec2d v)
161{
162 return vec2d (std::floor (v[0]), std::floor (v[1]));
163}
164 229
165static vec3d 230template<int N, typename T>
166floor (vec3d v) 231void
232permutation<N,T>::seed (seedable_rand_gen &rng)
167{ 233{
168 return vec3d (std::floor (v[0]), std::floor (v[1]), std::floor (v[2])); 234 for (int i = 0; i < N; ++i)
169} 235 pmap[i] = i;
170 236
171noise_gen<vec2d>::noise_gen (uint32_t seed) 237 // fisher-yates to randomly perturb
238 for (int i = N; --i; )
239 ::swap (pmap[i], pmap[rng (i + 1)]);
240}
241
242template class permutation<256, uint8_t>;
243
244/////////////////////////////////////////////////////////////////////////////
245
246template<class vec_t>
247void
248noise_gen_base<vec_t>::seed (seedable_rand_gen &rng)
249{
250 for (int i = 0; i < array_length (rvmap); ++i)
251 rvmap[i].seed (rng);
252}
253
254template<class vec_t>
255void
256noise_gen_base<vec_t>::seed (seed_t seed)
172{ 257{
173 seedable_rand_gen rng (seed); 258 seedable_rand_gen rng (seed);
174 259
175#if 1 260 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} 261}
209 262
263template<>
210vec2d::T_numtype 264vec2d::T_numtype
211noise_gen<vec2d>::operator() (vec2d P) 265noise_gen_base<vec2d>::operator() (vec2d P, uint32_t seed)
212{ 266{
213 vec2d I = floor (P); 267 vec2d I = floor (P);
214 vec2d F = P - I; 268 vec2d F = P - I;
215 269
216 float v = 0; 270 value_t v = 0;
271
272 seed *= 3039177861;
273 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
274 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
275
276 uint8_t h2 = rvmap[2](seed);
217 277
218 for (int j = -1; j <= 2; ++j) 278 for (int j = -1; j <= 2; ++j)
279 {
280 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
281
219 for (int i = -1; i <= 2; ++i) 282 for (int i = -1; i <= 2; ++i)
220 { 283 {
221 vec2d A = F - vec2d (i, j); 284 vec2d A = F - vec2d (i, j);
222
223 float d = dot (A, A); 285 value_t d = dot (A, A);
224 286
225 if (d < 4) 287 if (d < 4)
226 { 288 {
227 float t1 = 1 - d / 4; 289 value_t t1 = 1 - d / 4;
228 float t2 = t1 * t1; 290 value_t t2 = t1 * t1;
229 float t4 = t2 * t2; 291 value_t t4 = t2 * t2;
230 292
231 float p = (4 * t1 - 3) * t4; 293 value_t p = (4 * t1 - 3) * t4;
232 294
233 int h = rvmap [0](I[0] + i) ^ rvmap [1](I[1] + j); 295 uint8_t h = rvmap[0](i0 + i) ^ h1;
234 vec2d G = rvec [h & 0xff]; 296 vec2d G = charges2[h & 0xff];
235 297
236 v += dot (A, G) * p; 298 v += dot (A, G) * p;
237 } 299 }
238 } 300 }
301 }
239 302
240 return clamp (v, -.9999999f, .9999999f); 303 return v;
241} 304}
242 305
243///////////////////////////////////////////////////////////////////////////// 306/////////////////////////////////////////////////////////////////////////////
244 307
245noise_gen<vec3d>::noise_gen (uint32_t seed) 308template<>
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 309vec3d::T_numtype
255noise_gen<vec3d>::operator() (vec3d P) 310noise_gen_base<vec3d>::operator() (vec3d P, uint32_t seed)
256{ 311{
257 vec3d I = floor (P); 312 vec3d I = floor (P);
258 vec3d F = P - I; 313 vec3d F = P - I;
259 314
260 float v = 0; 315 seed *= 3039177861;
316 uint8_t i2 = uint8_t (I[2]) + (seed >> 24);
317 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
318 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
261 319
262 for (int j = -1; j <= 2; ++j) 320 uint8_t h3 = rvmap[3](seed);
263 for (int i = -1; i <= 2; ++i) 321
322 value_t v = 0;
323
264 for (int k = -1; k <= 2; ++k) 324 for (int k = -1; k <= 2; ++k)
325 {
326 uint8_t h2 = rvmap[2](i2 + k) ^ h3;
327
328 for (int j = -1; j <= 2; ++j)
265 { 329 {
266 vec3d A = F - vec3d (i, j, k); 330 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
267 float d = dot (A, A);
268 331
269 if (d < 4) 332 for (int i = -1; i <= 2; ++i)
270 { 333 {
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); 334 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); 335 value_t d = dot (A, A);
308 336
309 if (d < 4) 337 if (d < 4)
310 { 338 {
311 float t1 = 1 - d / 4; 339 value_t t1 = 1 - d / 4;
312 float t2 = t1 * t1; 340 value_t t2 = t1 * t1;
313 float t4 = t2 * t2; 341 value_t t4 = t2 * t2;
314 342
315 float o2 = o * o;
316
317 // (4t⁵ - 3t⁴) * (3o³ - 2o²) 343 // (4t⁵ - 3t⁴)
318 // alternative? ((o * 6 - 15) * o + 10) * o³ 344 value_t p = (4 * t1 - 3) * t4;
319 float p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
320 345
321 int h = rvmap[0](I[0] + i) ^ rvmap[1](I[1] + j) ^ rvmap[2](I[2] + k); 346 uint8_t h = rvmap[0](i0 + i) ^ h1;
322 const float *G = charges[h & 0xff]; 347 const value_t *G = charges3[h & 0xff];
323 348
324 v += dot (A, vec3d (G[0], G[1], G[2])) * p; 349 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
325 } 350 }
326 } 351 }
327 } 352 }
353 }
328 354
329 return clamp (v, -.9999999f, .9999999f); 355 return v * 2;
356}
357
358vec3d::T_numtype
359noise_gen<vec3d>::operator() (vec3d P, vec3d N, uint32_t seed)
360{
361 vec3d I = floor (P);
362 vec3d F = P - I;
363
364 seed *= 3039177861;
365 uint8_t i2 = uint8_t (I[2]) + (seed >> 24);
366 uint8_t i1 = uint8_t (I[1]) + (seed >> 16);
367 uint8_t i0 = uint8_t (I[0]) + (seed >> 8);
368
369 uint8_t h3 = rvmap[3](seed);
370
371 value_t v = 0;
372
373 for (int k = -1; k <= 2; ++k)
374 {
375 uint8_t h2 = rvmap[2](i2 + k) ^ h3;
376
377 for (int j = -1; j <= 2; ++j)
378 {
379 uint8_t h1 = rvmap[1](i1 + j) ^ h2;
380
381 for (int i = -1; i <= 2; ++i)
382 {
383 vec3d D = F - vec3d (i, j, k);
384 value_t e = dot (D, N);
385 value_t o = 1 - abs (e);
386
387 if (o > 0)
388 {
389 vec3d A = D - e * N;
390 value_t d = dot (A, A);
391
392 if (d < 4)
393 {
394 value_t t1 = 1 - d / 4;
395 value_t t2 = t1 * t1;
396 value_t t4 = t2 * t2;
397
398 value_t o2 = o * o;
399
400 // (4t⁵ - 3t⁴) * (3o³ - 2o²)
401 // alternative? ((o * 6 - 15) * o + 10) * o³
402 value_t p = (4 * t1 - 3) * t4 * (3 * o2 - 2 * o2 * o);
403
404 uint8_t h = rvmap[0](i0 + i) ^ h1;
405 const value_t *G = charges3[h & 0xff];
406
407 v += dot (A, vec3d (G[0], G[1], G[2])) * p;
408 }
409 }
410 }
411 }
412 }
413
414 return v;
330} 415}
331 416
332template class noise_gen<vec2d>; 417template class noise_gen<vec2d>;
333template class noise_gen<vec3d>; 418template class noise_gen<vec3d>;
334 419
335///////////////////////////////////////////////////////////////////////////// 420/////////////////////////////////////////////////////////////////////////////
336 421
337template<class vec_t> 422template<class vec_t>
338static vec_t 423frac_gen<vec_t>::frac_gen (int octaves, value_t lacunarity, value_t hurst_expo, seed_t seed)
339ith_octave (vec_t P, int i) 424: octaves (octaves), lac (lacunarity), h (hurst_expo)
340{ 425{
341 vec_t r = P; 426 this->seed (seed);
342 r[0] += i;
343 return r;
344}
345 427
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; 428 value_t exsum = 0;
429 value_t phi = noise (vec_t (value_t (0))) * 0.5 + 1;
351 430
352 for (int i = 0; i < MAX_OCTAVES; ++i) 431 for (int i = 0; i < octaves; ++i)
353 { 432 {
354 ex [i] = powf (lac, -h * i); 433 ex [i] = pow (lac, -h * i);
355 exsum += ex [i]; 434 exsum += ex [i];
356 fbm_mul [i] = 0.5f / (exsum * 0.75f); // .75f is a heuristic 435 fbm_mul [i] = 0.5 / (exsum * 0.75); // .75 is a heuristic
357 rot [i].set (0.4488f * i); 436 rot [i].set (phi * i + 1);
358 } 437 }
359} 438}
360 439
361template<class vec_t> 440template<class vec_t>
362typename frac_gen<vec_t>::value_t 441typename frac_gen<vec_t>::value_t
363frac_gen<vec_t>::fBm (vec_t P, int octaves) 442frac_gen<vec_t>::fBm (vec_t P)
364{ 443{
365 value_t v = 0.f; 444 value_t v = 0;
366 445
367 for (int i = 0; i < octaves; ++i) 446 for (int i = 0; i < octaves; ++i)
368 { 447 {
369 rot [i](P); 448 rot [i](P);
370 v += noise (ith_octave (P, i)) * ex [i]; 449 v += noise (P, i) * ex [i];
371 P *= lac; 450 P *= lac;
372 } 451 }
373 452
374 return clamp (v * fbm_mul [octaves - 1] + 0.5f, 0.f, .9999999f); 453 return v * fbm_mul [octaves - 1];
375} 454}
376 455
377template<class vec_t> 456template<class vec_t>
378typename frac_gen<vec_t>::value_t 457typename frac_gen<vec_t>::value_t
379frac_gen<vec_t>::turbulence (vec_t P, int octaves) 458frac_gen<vec_t>::turbulence (vec_t P)
380{ 459{
381 value_t v = 0.f; 460 value_t v = 0;
382 461
383 for (int i = 0; i < octaves; ++i) 462 for (int i = 0; i < octaves; ++i)
384 { 463 {
385 rot [i](P); 464 rot [i](P);
386 v += abs (noise (ith_octave (P, i))) * ex [i]; 465 v += abs (noise (P, i)) * ex [i];
387 P *= lac; 466 P *= lac;
388 } 467 }
389 468
390 return clamp (v * fbm_mul [octaves - 1] * 2.f, 0.f, .9999999f); 469 return v * fbm_mul [octaves - 1] * (0.5 / noise_gen<vec_t>::abs_avg ());
391} 470}
392 471
393template<class vec_t> 472template<class vec_t>
394typename frac_gen<vec_t>::value_t 473typename frac_gen<vec_t>::value_t
395frac_gen<vec_t>::multifractal (vec_t P, int octaves, value_t offset) 474frac_gen<vec_t>::multifractal (vec_t P, value_t offset)
396{ 475{
397 value_t v = 1.f; 476 value_t v = 1;
398 477
399 for (int i = 0; i < octaves; ++i) 478 for (int i = 0; i < octaves; ++i)
400 { 479 {
401 rot [i](P); 480 rot [i](P);
402 v *= noise (P) * ex [i] + offset; 481 v *= noise (P) * ex [i] + offset;
403 P *= lac; 482 P *= lac;
404 } 483 }
405 484
406 return clamp (v * 0.5f, 0.f, .9999999f); 485 return v * value_t (0.5);
407} 486}
408 487
409template<class vec_t> 488template<class vec_t>
410typename frac_gen<vec_t>::value_t 489typename frac_gen<vec_t>::value_t
411frac_gen<vec_t>::heterofractal (vec_t P, int octaves, value_t offset) 490frac_gen<vec_t>::heterofractal (vec_t P, value_t offset)
412{ 491{
413 value_t v = noise (P) + offset; 492 value_t v = noise (P) + offset;
414 int i;
415 493
416 for (i = 1; i < octaves; ++i) 494 for (int i = 1; i < octaves; ++i)
417 { 495 {
418 rot [i](P); 496 rot [i](P);
419 P *= lac; 497 P *= lac;
420 v += v * (noise (P) * ex [i] + offset); 498 v += v * (noise (P) * ex [i] + offset);
421 } 499 }
422 500
423 return v / powf (2., octaves); 501 return v / (1 << octaves);
424} 502}
425 503
426template<class vec_t> 504template<class vec_t>
427typename frac_gen<vec_t>::value_t 505typename frac_gen<vec_t>::value_t
428frac_gen<vec_t>::hybridfractal (vec_t P, int octaves, value_t offset, value_t gain) 506frac_gen<vec_t>::hybridfractal (vec_t P, value_t offset, value_t gain)
429{ 507{
430 value_t v = (noise (P) + offset) * ex [0]; 508 value_t v = (noise (P) + offset) * ex [0];
431 value_t weight = v; 509 value_t weight = v;
432 int i;
433 510
434 for (i = 1; i < octaves; ++i) 511 for (int i = 1; i < octaves; ++i)
435 { 512 {
436 rot [i](P); 513 rot [i](P);
437 P *= lac; 514 P *= lac;
438 515
439 min_it (weight, 1.f); 516 min_it (weight, 1);
440 517
441 value_t sig = (noise (P) + offset) * ex [i]; 518 value_t sig = (noise (P) + offset) * ex [i];
442 v += weight * sig; 519 v += weight * sig;
443 weight *= gain * sig; 520 weight *= gain * sig;
444 } 521 }
445 522
446 return clamp (v * 0.5f + 0.5f, 0.f, .9999999f); 523 return v * value_t (0.5) + value_t (0.5);
447} 524}
448 525
449template<class vec_t> 526template<class vec_t>
450typename frac_gen<vec_t>::value_t 527typename frac_gen<vec_t>::value_t
451frac_gen<vec_t>::ridgedmultifractal (vec_t P, int octaves, value_t offset, value_t gain) 528frac_gen<vec_t>::ridgedmultifractal (vec_t P, value_t offset, value_t gain)
452{ 529{
453 value_t sig = offset - abs (noise (P)); 530 value_t sig = offset - abs (noise (P));
454 sig *= sig; 531 sig *= sig;
455 value_t v = sig; 532 value_t v = sig;
456 533
457 for (int i = 1; i < octaves; ++i) 534 for (int i = 1; i < octaves; ++i)
458 { 535 {
459 rot [i](P); 536 rot [i](P);
460 P *= lac; 537 P *= lac;
461 538
539 // weight higher octaves by previous signal
462 value_t w = clamp (sig * gain, 0.f, 1.f); 540 value_t w = clamp (sig * gain, 0, 1);
463 541
464 sig = offset - abs (noise (P)); 542 sig = offset - abs (noise (P));
465 sig *= sig; 543 sig *= sig;
466 sig *= w; 544 sig *= w;
467 545
468 v += sig * ex [i]; 546 v += sig * ex [i];
469 } 547 }
470 548
471 return clamp (v * 0.25f, 0.f, .9999999f); 549 return v * value_t (0.25);
550}
551
552template<class vec_t>
553typename frac_gen<vec_t>::value_t
554frac_gen<vec_t>::billowfractal (vec_t P, value_t offset, value_t gain)
555{
556 value_t v = 0;
557
558 offset += 2 * noise_gen<vec_t>::abs_avg () - 1;
559
560 for (int i = 0; i < octaves; ++i)
561 {
562 rot [i](P);
563 v += (abs (noise (P, i)) * gain - offset) * ex [i];
564 P *= lac;
565 }
566
567 return v;
472} 568}
473 569
474// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2 570// http://www.gamasutra.com/view/feature/3098/a_realtime_procedural_universe_.php?page=2
475template<class vec_t> 571template<class vec_t>
476typename frac_gen<vec_t>::value_t 572typename frac_gen<vec_t>::value_t
477frac_gen<vec_t>::terrain (vec_t P, int octaves) 573frac_gen<vec_t>::terrain (vec_t P)
478{ 574{
479 value_t v = 0.f; 575 value_t v = 0;
480 576
481 for (int i = 0; i < octaves; ++i) 577 for (int i = 0; i < octaves; ++i)
482 { 578 {
483 rot [i](P); 579 rot [i](P);
484 v += noise (P) * ex [i]; 580 v += noise (P) * ex [i];
485 P *= lac; 581 P *= lac;
486 } 582 }
487 583
488 v *= fbm_mul [octaves - 1]; 584 v *= fbm_mul [octaves - 1];
489 585
490 return v <= 0.f ? - powf (-v, 0.7f) : powf (v, 1. + noise (P) * v); 586 return v <= 0 ? - pow (-v, 0.7) : pow (v, 1 + noise (P) * v);
491} 587}
492 588
493template<class vec_t> 589template<class vec_t>
494typename frac_gen<vec_t>::value_t 590typename frac_gen<vec_t>::value_t
495frac_gen<vec_t>::terrain2 (vec_t P, int octaves) 591frac_gen<vec_t>::terrain2 (vec_t P)
496{ 592{
497 value_t a = fBm (P, octaves); 593 value_t a = fBm (P);
498 value_t b = ridgedmultifractal (P, octaves, 1, 8); 594 value_t b = ridgedmultifractal (P, 1, 8);
499 value_t fade = fBm (P + vec_t(10.3), octaves); 595 value_t fade = fBm (P + vec_t(10.3));
500 596
501 const value_t width = 0.05f; 597 const value_t width = 0.05;
502 598
503 if (fade > 0.5f + width) 599 if (fade > 0.5 + width)
504 return a; 600 return a;
505 else if (fade < 0.5f - width) 601 else if (fade < 0.5 - width)
506 return b; 602 return b;
507 603
508 fade = (fade - 0.5f + width) / (width * 2); 604 fade = (fade - 0.5 + width) / (width * 2);
509 605
510 // sigmoidal curve 606 // sigmoidal curve
511 fade = fade * fade * 2 * (1.5f - fade); 607 fade = fade * fade * 2 * (1.5 - fade);
512 608
513 return a * fade + b * (1 - fade); 609 return a * fade + b * (1 - fade);
514} 610}
515 611
516template class frac_gen<vec2d>; 612template class frac_gen<vec2d>;
517template class frac_gen<vec3d>; 613template class frac_gen<vec3d>;
518 614
519///////////////////////////////////////////////////////////////////////////// 615/////////////////////////////////////////////////////////////////////////////
520 616
617template<typename T, typename U>
618T
619inline border_blend (T a, T b, vec2d P, U N, U W)
620{
621 U border = W; // within n places of the border
622
623 min_it (border, P [0]);
624 min_it (border, N - P [0]);
625 min_it (border, P [1]);
626 min_it (border, N - P [1]);
627
628 return blend (a, b,border, U(0), W);
629}
630
631static void
632gen_height (int x, int y)
633{
634 vec2d P = vec2d (x, y);
635
636 static frac2d gen(13);
637
638 static frac2d vec_gen1 (6, 2, 0.5, 1);
639 static frac2d vec_gen2 (6, 2, 0.5, 2);
640
641 const float continent_scale = 0.00008;
642
643 vec2d perturb_pos = pow (P, 1.4) * 1e-5;
644
645 vec2d perturb (
646 vec_gen1.fBm (perturb_pos),
647 vec_gen2.fBm (perturb_pos)
648 );
649
650 float perturb_perturb = 1 - (P[1] - P[0]) * (1. / 25000 / 2);
651 perturb_perturb = perturb_perturb * perturb_perturb * 0.4;
652 perturb *= perturb_perturb;
653
654 vec2d P_continent = P * continent_scale + perturb;
655
656 static frac2d continent_gen (13, 2.13, 0.5);
657 float continent = continent_gen.fBm (P_continent) + 0.05f;
658
659 float land_gradient = sigmoid1 (P[0] * (1. / 25000));
660
661 const float W = 1000 * continent_scale;
662 const float N = (25000 - 1) * continent_scale;
663
664 continent = border_blend (-1.f, continent, P_continent , N, 400 * continent_scale);
665 continent = border_blend (-1.f, continent, P * continent_scale + perturb * 0.1, N, 100 * continent_scale);
666
667 vec3d c;
668 float v;
669
670 if (continent < 0)
671 {
672 // ocean
673
674 v = min (continent * 10, -0.2f);
675 c = vec3d (0, 0, 1);
676 }
677 else
678 {
679 // continent
680
681 // big rivers
682 static frac2d river_gen (1);
683 float river1 = abs (river_gen.fBm (P * 0.001 + perturb * 4));
684 float river2 = river_gen.ridgedmultifractal (P * 0.04 + vec2d (3, 5), 0.8, 10) - (P[1] / 25000) * 0.1;
685
686 if (river1 < 0.03f)
687 {
688 v = min (-0.1f, -river1);
689 c = vec3d (0.2, 0.2, 1);
690 }
691 else if (river1 < 0.2f && river2 > 0.1f)
692 {
693 v = -0.05f;
694 c = vec3d (0.4, 0.4, 1);
695 }
696 else
697 {
698 //c = river1 > 0 ? vec3d (0.8, 0.8, 0) : vec3d (0.8, 0, 0);
699 c = blend0 (vec3d (0.8, 0, 0), vec3d (0.8, 0.8, 0), 0.01f, river1);
700
701 static frac2d mountain_gen (8, 2.14, 0.5);
702 float mountain = mountain_gen.ridgedmultifractal (P * 0.004);
703 v = blend0 (mountain * 3 - 1, continent, 0.05f, river1);
704 }
705 }
706
707 c *= v * 0.5 + 0.5;
708
709 putc (clamp<int> (255 * c[0], 0, 255), stdout);
710 putc (clamp<int> (255 * c[1], 0, 255), stdout);
711 putc (clamp<int> (255 * c[2], 0, 255), stdout);
712}
713
714void noise_test ();
715void noise_test ()
716{
521#if 0 717#if 1
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; 718 int Nw = 700;
529 719
530 printf ("P5 %d %d 255\n", N, N); 720 printf ("P6 %d %d 255\n", Nw * 3, Nw * 2);
531 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm 721 // 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) 722 for (int y = 0; y < Nw; ++y)
533 { 723 {
534 if (!(y&63))fprintf (stderr, "y %d\n", y);//D 724 if (!(y&63))fprintf (stderr, "y %d\n", y * 50 / Nw);//D
725
726 for (int x = 0; x < Nw; ++x) gen_height (x * 25000 / Nw, y * 25000 / Nw);
727
728 for (int x = 0; x < Nw; ++x) gen_height (x, y);
729 for (int x = 0; x < Nw; ++x) gen_height (x + 22000, y + 2000);
730 }
535 for (int x = 0; x < N; ++x) 731 for (int y = 0; y < Nw; ++y)
536 { 732 {
733 if (!(y&63))fprintf (stderr, "y %d\n", y * 50 / Nw+50);//D
734
735 for (int x = 0; x < Nw; ++x) gen_height (x + 1000, y + 22000);
736 for (int x = 0; x < Nw; ++x) gen_height (x + 12000, y + 12000);
737 for (int x = 0; x < Nw; ++x) gen_height (x + 22000, y + 22000);
738 }
739
537 //putc (127 * n.noise (x * 0.1, y * 0.1, 0, 0,0,1) + 128, stdout); 740 //putc (127 * gen.noise (vec2d (x * 0.01, y * 0.01)) + 128, stdout);
538 //putc (256 * gen.terrain2 (x * 0.004, y * 0.004, 8), stdout); 741 //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); 742 //putc (256 * gen.fBm (vec2d(x * 0.01, y * 0.01), 16), stdout);
540 //putc (256 * gen.turbulence (x * 0.004 - 1, y * 0.004 - 1, 8), stdout); 743 //putc (256 * gen.turbulence (vec2d (x * 0.004 - 1, y * 0.004 - 1), 10), stdout);
541 //putc (256 * gen.heterofractal (x * 0.008, y * 0.008, 8, 0.9), stdout); 744 //putc (256 * gen.heterofractal (vec2d (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); 745 //putc (256 * gen.hybridfractal (vec2d (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); 746 //putc (256 * gen.fBm (vec2d (x * 0.002, y * 0.002), 2), stdout);
548 // rain 747 //putc (127.49 * gen.billowfractal (vec2d (x * 0.01, y * 0.01), 9) + 128, stdout);
549 //putc (256 * gen.ridgedmultifractal (x * 0.01, y * 0.01, 3, 1.03, 2), stdout);
550 }
551 }
552#else 748#else
553 int N = 512; 749 int N = 128;
554 750
555 //printf ("P6 %d %d 255\n", N, N); 751 //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 752 // pmake&&server/deliantra-server >x&&convert -depth 8 -size 512xx512 gray:x x.ppm&& cv x.ppm
753 frac3d gen3 (3);;
557 for (int z = 0; z < N; ++z) 754 for (int z = 0; z < N; ++z)
558 { 755 {
559 if (!(z&7))fprintf (stderr, "z %d\n", z);//D 756 if (!(z&7))fprintf (stderr, "z %d\n", z);//D
560 for (int y = 0; y < N; ++y) 757 for (int y = 0; y < N; ++y)
561 for (int x = 0; x < N; ++x) 758 for (int x = 0; x < N; ++x)
562 { 759 {
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; 760 float v = gen3.ridgedmultifractal (vec3d (x * 0.001 + 0.2, y * 0.001 + 0.2, z * 0.01 + 0.2), 1.03, 2) * 2;
564 761
565#if 0 762#if 0
566 if (z < 64) 763 if (z < 64)
567 v = v * (z * z) / (64 * 64); 764 v = v * (z * z) / (64 * 64);
568#endif 765#endif
569 766
570 if (v <= 0.9999) 767 if (v <= 0.9)
571 continue; 768 continue;
572 769
573 float r[4]; 770 float r[4];
574 int i[4]; 771 int i[4];
575 772
590 } 787 }
591#endif 788#endif
592 789
593 exit (0); 790 exit (0);
594} 791}
595#endif

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