source/blender/render/intern/source/strand.c

   1 /*
   2  * ***** BEGIN GPL LICENSE BLOCK *****
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  17  *
  18  * Contributors: Brecht Van Lommel.
  19  *
  20  * ***** END GPL LICENSE BLOCK *****
  21  */
  22
  23 /** \file blender/render/intern/source/strand.c
  24  *  \ingroup render
  25  */
  26
  27
  28 #include <math.h>
  29 #include <string.h>
  30 #include <stdlib.h>
  31
  32 #include "MEM_guardedalloc.h"
  33
  34 #include "DNA_key_types.h"
  35 #include "DNA_material_types.h"
  36 #include "DNA_meshdata_types.h"
  37
  38 #include "BLI_math.h"
  39 #include "BLI_blenlib.h"
  40 #include "BLI_utildefines.h"
  41 #include "BLI_ghash.h"
  42 #include "BLI_memarena.h"
  43 #include "BLI_rand.h"
  44
  45 #include "BKE_DerivedMesh.h"
  46 #include "BKE_key.h"
  47
  48
  49 #include "render_types.h"
  50 #include "initrender.h"
  51 #include "rendercore.h"
  52 #include "renderdatabase.h"
  53 #include "renderpipeline.h"
  54 #include "pixelblending.h"
  55 #include "shading.h"
  56 #include "strand.h"
  57 #include "zbuf.h"
  58
  59 /* *************** */
  60
  61 static float strand_eval_width(Material *ma, float strandco)
  62 {
  63         float fac;
  64
  65         strandco= 0.5f*(strandco + 1.0f);
  66
  67         if (ma->strand_ease!=0.0f) {
  68                 if (ma->strand_ease<0.0f)
  69                         fac= pow(strandco, 1.0f+ma->strand_ease);
  70                 else
  71                         fac= pow(strandco, 1.0f/(1.0f-ma->strand_ease));
  72         }
  73         else fac= strandco;
  74
  75         return ((1.0f-fac)*ma->strand_sta + (fac)*ma->strand_end);
  76 }
  77
  78 void strand_eval_point(StrandSegment *sseg, StrandPoint *spoint)
  79 {
  80         Material *ma;
  81         StrandBuffer *strandbuf;
  82         float *simplify;
  83         float p[4][3], data[4], cross[3], w, dx, dy, t;
  84         int type;
  85
  86         strandbuf= sseg->buffer;
  87         ma= sseg->buffer->ma;
  88         t= spoint->t;
  89         type= (strandbuf->flag & R_STRAND_BSPLINE)? KEY_BSPLINE: KEY_CARDINAL;
  90
  91         copy_v3_v3(p[0], sseg->v[0]->co);
  92         copy_v3_v3(p[1], sseg->v[1]->co);
  93         copy_v3_v3(p[2], sseg->v[2]->co);
  94         copy_v3_v3(p[3], sseg->v[3]->co);
  95
  96         if (sseg->obi->flag & R_TRANSFORMED) {
  97                 mul_m4_v3(sseg->obi->mat, p[0]);
  98                 mul_m4_v3(sseg->obi->mat, p[1]);
  99                 mul_m4_v3(sseg->obi->mat, p[2]);
 100                 mul_m4_v3(sseg->obi->mat, p[3]);
 101         }
 102
 103         if (t == 0.0f) {
 104                 copy_v3_v3(spoint->co, p[1]);
 105                 spoint->strandco= sseg->v[1]->strandco;
 106
 107                 spoint->dtstrandco= (sseg->v[2]->strandco - sseg->v[0]->strandco);
 108                 if (sseg->v[0] != sseg->v[1])
 109                         spoint->dtstrandco *= 0.5f;
 110         }
 111         else if (t == 1.0f) {
 112                 copy_v3_v3(spoint->co, p[2]);
 113                 spoint->strandco= sseg->v[2]->strandco;
 114
 115                 spoint->dtstrandco= (sseg->v[3]->strandco - sseg->v[1]->strandco);
 116                 if (sseg->v[3] != sseg->v[2])
 117                         spoint->dtstrandco *= 0.5f;
 118         }
 119         else {
 120                 key_curve_position_weights(t, data, type);
 121                 spoint->co[0]= data[0]*p[0][0] + data[1]*p[1][0] + data[2]*p[2][0] + data[3]*p[3][0];
 122                 spoint->co[1]= data[0]*p[0][1] + data[1]*p[1][1] + data[2]*p[2][1] + data[3]*p[3][1];
 123                 spoint->co[2]= data[0]*p[0][2] + data[1]*p[1][2] + data[2]*p[2][2] + data[3]*p[3][2];
 124                 spoint->strandco= (1.0f-t)*sseg->v[1]->strandco + t*sseg->v[2]->strandco;
 125         }
 126
 127         key_curve_tangent_weights(t, data, type);
 128         spoint->dtco[0]= data[0]*p[0][0] + data[1]*p[1][0] + data[2]*p[2][0] + data[3]*p[3][0];
 129         spoint->dtco[1]= data[0]*p[0][1] + data[1]*p[1][1] + data[2]*p[2][1] + data[3]*p[3][1];
 130         spoint->dtco[2]= data[0]*p[0][2] + data[1]*p[1][2] + data[2]*p[2][2] + data[3]*p[3][2];
 131
 132         normalize_v3_v3(spoint->tan, spoint->dtco);
 133         normalize_v3_v3(spoint->nor, spoint->co);
 134         negate_v3(spoint->nor);
 135
 136         spoint->width= strand_eval_width(ma, spoint->strandco);
 137
 138         /* simplification */
 139         simplify= RE_strandren_get_simplify(strandbuf->obr, sseg->strand, 0);
 140         spoint->alpha= (simplify)? simplify[1]: 1.0f;
 141
 142         /* outer points */
 143         cross_v3_v3v3(cross, spoint->co, spoint->tan);
 144
 145         w= spoint->co[2]*strandbuf->winmat[2][3] + strandbuf->winmat[3][3];
 146         dx= strandbuf->winx*cross[0]*strandbuf->winmat[0][0]/w;
 147         dy= strandbuf->winy*cross[1]*strandbuf->winmat[1][1]/w;
 148         w= sqrt(dx*dx + dy*dy);
 149
 150         if (w > 0.0f) {
 151                 if (strandbuf->flag & R_STRAND_B_UNITS) {
 152                         const float crosslen= len_v3(cross);
 153                         w= 2.0f*crosslen*strandbuf->minwidth/w;
 154
 155                         if (spoint->width < w) {
 156                                 spoint->alpha= spoint->width/w;
 157                                 spoint->width= w;
 158                         }
 159
 160                         if (simplify)
 161                                 /* squared because we only change width, not length */
 162                                 spoint->width *= simplify[0]*simplify[0];
 163
 164                         mul_v3_fl(cross, spoint->width*0.5f/crosslen);
 165                 }
 166                 else
 167                         mul_v3_fl(cross, spoint->width/w);
 168         }
 169
 170         sub_v3_v3v3(spoint->co1, spoint->co, cross);
 171         add_v3_v3v3(spoint->co2, spoint->co, cross);
 172
 173         copy_v3_v3(spoint->dsco, cross);
 174 }
 175
 176 /* *************** */
 177
 178 static void interpolate_vec1(float *v1, float *v2, float t, float negt, float *v)
 179 {
 180         v[0]= negt*v1[0] + t*v2[0];
 181 }
 182
 183 static void interpolate_vec3(float *v1, float *v2, float t, float negt, float *v)
 184 {
 185         v[0]= negt*v1[0] + t*v2[0];
 186         v[1]= negt*v1[1] + t*v2[1];
 187         v[2]= negt*v1[2] + t*v2[2];
 188 }
 189
 190 static void interpolate_vec4(float *v1, float *v2, float t, float negt, float *v)
 191 {
 192         v[0]= negt*v1[0] + t*v2[0];
 193         v[1]= negt*v1[1] + t*v2[1];
 194         v[2]= negt*v1[2] + t*v2[2];
 195         v[3]= negt*v1[3] + t*v2[3];
 196 }
 197
 198 static void interpolate_shade_result(ShadeResult *shr1, ShadeResult *shr2, float t, ShadeResult *shr, int addpassflag)
 199 {
 200         float negt= 1.0f - t;
 201
 202         interpolate_vec4(shr1->combined, shr2->combined, t, negt, shr->combined);
 203
 204         if (addpassflag & SCE_PASS_VECTOR) {
 205                 interpolate_vec4(shr1->winspeed, shr2->winspeed, t, negt, shr->winspeed);
 206         }
 207         /* optim... */
 208         if (addpassflag & ~(SCE_PASS_VECTOR)) {
 209                 if (addpassflag & SCE_PASS_Z)
 210                         interpolate_vec1(&shr1->z, &shr2->z, t, negt, &shr->z);
 211                 if (addpassflag & SCE_PASS_RGBA)
 212                         interpolate_vec4(shr1->col, shr2->col, t, negt, shr->col);
 213                 if (addpassflag & SCE_PASS_NORMAL) {
 214                         interpolate_vec3(shr1->nor, shr2->nor, t, negt, shr->nor);
 215                         normalize_v3(shr->nor);
 216                 }
 217                 if (addpassflag & SCE_PASS_EMIT)
 218                         interpolate_vec3(shr1->emit, shr2->emit, t, negt, shr->emit);
 219                 if (addpassflag & SCE_PASS_DIFFUSE) {
 220                         interpolate_vec3(shr1->diff, shr2->diff, t, negt, shr->diff);
 221                         interpolate_vec3(shr1->diffshad, shr2->diffshad, t, negt, shr->diffshad);
 222                 }
 223                 if (addpassflag & SCE_PASS_SPEC)
 224                         interpolate_vec3(shr1->spec, shr2->spec, t, negt, shr->spec);
 225                 if (addpassflag & SCE_PASS_SHADOW)
 226                         interpolate_vec3(shr1->shad, shr2->shad, t, negt, shr->shad);
 227                 if (addpassflag & SCE_PASS_AO)
 228                         interpolate_vec3(shr1->ao, shr2->ao, t, negt, shr->ao);
 229                 if (addpassflag & SCE_PASS_ENVIRONMENT)
 230                         interpolate_vec3(shr1->env, shr2->env, t, negt, shr->env);
 231                 if (addpassflag & SCE_PASS_INDIRECT)
 232                         interpolate_vec3(shr1->indirect, shr2->indirect, t, negt, shr->indirect);
 233                 if (addpassflag & SCE_PASS_REFLECT)
 234                         interpolate_vec3(shr1->refl, shr2->refl, t, negt, shr->refl);
 235                 if (addpassflag & SCE_PASS_REFRACT)
 236                         interpolate_vec3(shr1->refr, shr2->refr, t, negt, shr->refr);
 237                 if (addpassflag & SCE_PASS_MIST)
 238                         interpolate_vec1(&shr1->mist, &shr2->mist, t, negt, &shr->mist);
 239         }
 240 }
 241
 242 static void strand_apply_shaderesult_alpha(ShadeResult *shr, float alpha)
 243 {
 244         if (alpha < 1.0f) {
 245                 shr->combined[0] *= alpha;
 246                 shr->combined[1] *= alpha;
 247                 shr->combined[2] *= alpha;
 248                 shr->combined[3] *= alpha;
 249
 250                 shr->col[0] *= alpha;
 251                 shr->col[1] *= alpha;
 252                 shr->col[2] *= alpha;
 253                 shr->col[3] *= alpha;
 254
 255                 shr->alpha *= alpha;
 256         }
 257 }
 258
 259 static void strand_shade_point(Render *re, ShadeSample *ssamp, StrandSegment *sseg, StrandVert *svert, StrandPoint *spoint)
 260 {
 261         ShadeInput *shi= ssamp->shi;
 262         ShadeResult *shr= ssamp->shr;
 263         VlakRen vlr;
 264         int seed;
 265
 266         memset(&vlr, 0, sizeof(vlr));
 267         vlr.flag= R_SMOOTH;
 268         if (sseg->buffer->ma->mode & MA_TANGENT_STR)
 269                 vlr.flag |= R_TANGENT;
 270
 271         shi->vlr= &vlr;
 272         shi->v1= NULL;
 273         shi->v2= NULL;
 274         shi->v3= NULL;
 275         shi->strand= sseg->strand;
 276         shi->obi= sseg->obi;
 277         shi->obr= sseg->obi->obr;
 278
 279         /* cache for shadow */
 280         shi->samplenr= re->shadowsamplenr[shi->thread]++;
 281
 282         /* all samples */
 283         shi->mask= 0xFFFF;
 284
 285         /* seed RNG for consistent results across tiles */
 286         seed = shi->strand->index + (svert - shi->strand->vert);
 287         BLI_thread_srandom(shi->thread, seed);
 288
 289         shade_input_set_strand(shi, sseg->strand, spoint);
 290         shade_input_set_strand_texco(shi, sseg->strand, sseg->v[1], spoint);
 291
 292         /* init material vars */
 293         shade_input_init_material(shi);
 294
 295         /* shade */
 296         shade_samples_do_AO(ssamp);
 297         shade_input_do_shade(shi, shr);
 298
 299         /* apply simplification */
 300         strand_apply_shaderesult_alpha(shr, spoint->alpha);
 301
 302         /* include lamphalos for strand, since halo layer was added already */
 303         if (re->flag & R_LAMPHALO)
 304                 if (shi->layflag & SCE_LAY_HALO)
 305                         renderspothalo(shi, shr->combined, shr->combined[3]);
 306
 307         shi->strand= NULL;
 308 }
 309
 310 /* *************** */
 311
 312 struct StrandShadeCache {
 313         GHash *resulthash;
 314         GHash *refcounthash;
 315         MemArena *memarena;
 316 };
 317
 318 typedef struct StrandCacheEntry {
 319         GHashPair pair;
 320         ShadeResult shr;
 321 } StrandCacheEntry;
 322
 323 StrandShadeCache *strand_shade_cache_create(void)
 324 {
 325         StrandShadeCache *cache;
 326
 327         cache= MEM_callocN(sizeof(StrandShadeCache), "StrandShadeCache");
 328         cache->resulthash= BLI_ghash_pair_new("strand_shade_cache_create1 gh");
 329         cache->refcounthash= BLI_ghash_pair_new("strand_shade_cache_create2 gh");
 330         cache->memarena= BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, "strand shade cache arena");
 331
 332         return cache;
 333 }
 334
 335 void strand_shade_cache_free(StrandShadeCache *cache)
 336 {
 337         BLI_ghash_free(cache->refcounthash, NULL, NULL);
 338         BLI_ghash_free(cache->resulthash, MEM_freeN, NULL);
 339         BLI_memarena_free(cache->memarena);
 340         MEM_freeN(cache);
 341 }
 342
 343 static GHashPair strand_shade_hash_pair(ObjectInstanceRen *obi, StrandVert *svert)
 344 {
 345         GHashPair pair = {obi, svert};
 346         return pair;
 347 }
 348
 349 static void strand_shade_get(Render *re, StrandShadeCache *cache, ShadeSample *ssamp, StrandSegment *sseg, StrandVert *svert)
 350 {
 351         StrandCacheEntry *entry;
 352         StrandPoint p;
 353         int *refcount;
 354         GHashPair pair = strand_shade_hash_pair(sseg->obi, svert);
 355
 356         entry= BLI_ghash_lookup(cache->resulthash, &pair);
 357         refcount= BLI_ghash_lookup(cache->refcounthash, &pair);
 358
 359         if (!entry) {
 360                 /* not shaded yet, shade and insert into hash */
 361                 p.t= (sseg->v[1] == svert)? 0.0f: 1.0f;
 362                 strand_eval_point(sseg, &p);
 363                 strand_shade_point(re, ssamp, sseg, svert, &p);
 364
 365                 entry= MEM_callocN(sizeof(StrandCacheEntry), "StrandCacheEntry");
 366                 entry->pair = pair;
 367                 entry->shr = ssamp->shr[0];
 368                 BLI_ghash_insert(cache->resulthash, entry, entry);
 369         }
 370         else
 371                 /* already shaded, just copy previous result from hash */
 372                 ssamp->shr[0]= entry->shr;
 373
 374         /* lower reference count and remove if not needed anymore by any samples */
 375         (*refcount)--;
 376         if (*refcount == 0) {
 377                 BLI_ghash_remove(cache->resulthash, &pair, MEM_freeN, NULL);
 378                 BLI_ghash_remove(cache->refcounthash, &pair, NULL, NULL);
 379         }
 380 }
 381
 382 void strand_shade_segment(Render *re, StrandShadeCache *cache, StrandSegment *sseg, ShadeSample *ssamp, float t, float s, int addpassflag)
 383 {
 384         ShadeResult shr1, shr2;
 385
 386         /* get shading for two endpoints and interpolate */
 387         strand_shade_get(re, cache, ssamp, sseg, sseg->v[1]);
 388         shr1= ssamp->shr[0];
 389         strand_shade_get(re, cache, ssamp, sseg, sseg->v[2]);
 390         shr2= ssamp->shr[0];
 391
 392         interpolate_shade_result(&shr1, &shr2, t, ssamp->shr, addpassflag);
 393
 394         /* apply alpha along width */
 395         if (sseg->buffer->widthfade != -1.0f) {
 396                 s = 1.0f - powf(fabsf(s), sseg->buffer->widthfade);
 397
 398                 strand_apply_shaderesult_alpha(ssamp->shr, s);
 399         }
 400 }
 401
 402 void strand_shade_unref(StrandShadeCache *cache, ObjectInstanceRen *obi, StrandVert *svert)
 403 {
 404         GHashPair pair = strand_shade_hash_pair(obi, svert);
 405         int *refcount;
 406
 407         /* lower reference count and remove if not needed anymore by any samples */
 408         refcount= BLI_ghash_lookup(cache->refcounthash, &pair);
 409
 410         (*refcount)--;
 411         if (*refcount == 0) {
 412                 BLI_ghash_remove(cache->resulthash, &pair, MEM_freeN, NULL);
 413                 BLI_ghash_remove(cache->refcounthash, &pair, NULL, NULL);
 414         }
 415 }
 416
 417 static void strand_shade_refcount(StrandShadeCache *cache, StrandSegment *sseg, StrandVert *svert)
 418 {
 419         GHashPair pair = strand_shade_hash_pair(sseg->obi, svert);
 420         GHashPair *key;
 421         int *refcount= BLI_ghash_lookup(cache->refcounthash, &pair);
 422
 423         if (!refcount) {
 424                 key= BLI_memarena_alloc(cache->memarena, sizeof(GHashPair));
 425                 *key = pair;
 426                 refcount= BLI_memarena_alloc(cache->memarena, sizeof(int));
 427                 *refcount= 1;
 428                 BLI_ghash_insert(cache->refcounthash, key, refcount);
 429         }
 430         else
 431                 (*refcount)++;
 432 }
 433
 434 /* *************** */
 435
 436 typedef struct StrandPart {
 437         Render *re;
 438         ZSpan *zspan;
 439
 440         APixstrand *apixbuf;
 441         int *totapixbuf;
 442         int *rectz;
 443         int *rectmask;
 444         intptr_t *rectdaps;
 445         int rectx, recty;
 446         int sample;
 447         int shadow;
 448         float (*jit)[2];
 449         int samples;
 450
 451         StrandSegment *segment;
 452         float t[3], s[3];
 453
 454         StrandShadeCache *cache;
 455 } StrandPart;
 456
 457 typedef struct StrandSortSegment {
 458         struct StrandSortSegment *next;
 459         int obi, strand, segment;
 460         float z;
 461 } StrandSortSegment;
 462
 463 static int compare_strand_segment(const void *poin1, const void *poin2)
 464 {
 465         const StrandSortSegment *seg1= (const StrandSortSegment*)poin1;
 466         const StrandSortSegment *seg2= (const StrandSortSegment*)poin2;
 467
 468         if (seg1->z < seg2->z)
 469                 return -1;
 470         else if (seg1->z == seg2->z)
 471                 return 0;
 472         else
 473                 return 1;
 474 }
 475
 476 static void do_strand_point_project(float winmat[4][4], ZSpan *zspan, float *co, float *hoco, float *zco)
 477 {
 478         projectvert(co, winmat, hoco);
 479         hoco_to_zco(zspan, zco, hoco);
 480 }
 481
 482 static void strand_project_point(float winmat[4][4], float winx, float winy, StrandPoint *spoint)
 483 {
 484         float div;
 485
 486         projectvert(spoint->co, winmat, spoint->hoco);
 487
 488         div= 1.0f/spoint->hoco[3];
 489         spoint->x= spoint->hoco[0]*div*winx*0.5f;
 490         spoint->y= spoint->hoco[1]*div*winy*0.5f;
 491 }
 492
 493 static APixstrand *addpsmainAstrand(ListBase *lb)
 494 {
 495         APixstrMain *psm;
 496
 497         psm= MEM_mallocN(sizeof(APixstrMain), "addpsmainA");
 498         BLI_addtail(lb, psm);
 499         psm->ps = MEM_callocN(4096 * sizeof(APixstrand), "pixstr");
 500
 501         return psm->ps;
 502 }
 503
 504 static APixstrand *addpsAstrand(ZSpan *zspan)
 505 {
 506         /* make new PS */
 507         if (zspan->apstrandmcounter==0) {
 508                 zspan->curpstrand= addpsmainAstrand(zspan->apsmbase);
 509                 zspan->apstrandmcounter= 4095;
 510         }
 511         else {
 512                 zspan->curpstrand++;
 513                 zspan->apstrandmcounter--;
 514         }
 515         return zspan->curpstrand;
 516 }
 517
 518 #define MAX_ZROW        2000
 519
 520 static void do_strand_fillac(void *handle, int x, int y, float u, float v, float z)
 521 {
 522         StrandPart *spart= (StrandPart *)handle;
 523         StrandShadeCache *cache= spart->cache;
 524         StrandSegment *sseg= spart->segment;
 525         APixstrand *apn, *apnew;
 526         float t, s;
 527         int offset, mask, obi, strnr, seg, zverg, bufferz, maskz=0;
 528
 529         offset = y*spart->rectx + x;
 530         obi= sseg->obi - spart->re->objectinstance;
 531         strnr= sseg->strand->index + 1;
 532         seg= sseg->v[1] - sseg->strand->vert;
 533         mask= (1<<spart->sample);
 534
 535         /* check against solid z-buffer */
 536         zverg= (int)z;
 537
 538         if (spart->rectdaps) {
 539                 /* find the z of the sample */
 540                 PixStr *ps;
 541                 intptr_t *rd= spart->rectdaps + offset;
 542
 543                 bufferz= 0x7FFFFFFF;
 544                 if (spart->rectmask) maskz= 0x7FFFFFFF;
 545
 546                 if (*rd) {
 547                         for (ps= (PixStr *)(*rd); ps; ps= ps->next) {
 548                                 if (mask & ps->mask) {
 549                                         bufferz= ps->z;
 550                                         if (spart->rectmask)
 551                                                 maskz= ps->maskz;
 552                                         break;
 553                                 }
 554                         }
 555                 }
 556         }
 557         else {
 558                 bufferz= (spart->rectz)? spart->rectz[offset]: 0x7FFFFFFF;
 559                 if (spart->rectmask)
 560                         maskz= spart->rectmask[offset];
 561         }
 562
 563 #define CHECK_ADD(n) \
 564         if (apn->p[n]==strnr && apn->obi[n]==obi && apn->seg[n]==seg) \
 565         { if (!(apn->mask[n] & mask)) { apn->mask[n] |= mask; apn->v[n] += t; apn->u[n] += s; } break; } (void)0
 566 #define CHECK_ASSIGN(n) \
 567         if (apn->p[n]==0) \
 568         {apn->obi[n]= obi; apn->p[n]= strnr; apn->z[n]= zverg; apn->mask[n]= mask; apn->v[n]= t; apn->u[n]= s; apn->seg[n]= seg; break; } (void)0
 569
 570         /* add to pixel list */
 571         if (zverg < bufferz && (spart->totapixbuf[offset] < MAX_ZROW)) {
 572                 if (!spart->rectmask || zverg > maskz) {
 573                         t = u * spart->t[0] + v * spart->t[1] + (1.0f - u - v) * spart->t[2];
 574                         s = fabsf(u * spart->s[0] + v * spart->s[1] + (1.0f - u - v) * spart->s[2]);
 575
 576                         apn= spart->apixbuf + offset;
 577                         while (apn) {
 578                                 CHECK_ADD(0);
 579                                 CHECK_ADD(1);
 580                                 CHECK_ADD(2);
 581                                 CHECK_ADD(3);
 582                                 CHECK_ASSIGN(0);
 583                                 CHECK_ASSIGN(1);
 584                                 CHECK_ASSIGN(2);
 585                                 CHECK_ASSIGN(3);
 586
 587                                 apnew= addpsAstrand(spart->zspan);
 588                                 SWAP(APixstrand, *apnew, *apn);
 589                                 apn->next= apnew;
 590                                 CHECK_ASSIGN(0);
 591                         }
 592
 593                         if (cache) {
 594                                 strand_shade_refcount(cache, sseg, sseg->v[1]);
 595                                 strand_shade_refcount(cache, sseg, sseg->v[2]);
 596                         }
 597                         spart->totapixbuf[offset]++;
 598                 }
 599         }
 600 }
 601
 602 /* width is calculated in hoco space, to ensure strands are visible */
 603 static int strand_test_clip(float winmat[4][4], ZSpan *UNUSED(zspan), float *bounds, float *co, float *zcomp, float widthx, float widthy)
 604 {
 605         float hoco[4];
 606         int clipflag= 0;
 607
 608         projectvert(co, winmat, hoco);
 609
 610         /* we compare z without perspective division for segment sorting */
 611         *zcomp= hoco[2];
 612
 613         if (hoco[0]+widthx < bounds[0]*hoco[3]) clipflag |= 1;
 614         else if (hoco[0]-widthx > bounds[1]*hoco[3]) clipflag |= 2;
 615
 616         if (hoco[1]-widthy > bounds[3]*hoco[3]) clipflag |= 4;
 617         else if (hoco[1]+widthy < bounds[2]*hoco[3]) clipflag |= 8;
 618
 619         clipflag |= testclip(hoco);
 620
 621         return clipflag;
 622 }
 623
 624 static void do_scanconvert_strand(Render *UNUSED(re), StrandPart *spart, ZSpan *zspan, float t, float dt, float *co1, float *co2, float *co3, float *co4, int sample)
 625 {
 626         float jco1[3], jco2[3], jco3[3], jco4[3], jx, jy;
 627
 628         copy_v3_v3(jco1, co1);
 629         copy_v3_v3(jco2, co2);
 630         copy_v3_v3(jco3, co3);
 631         copy_v3_v3(jco4, co4);
 632
 633         if (spart->jit) {
 634                 jx= -spart->jit[sample][0];
 635                 jy= -spart->jit[sample][1];
 636
 637                 jco1[0] += jx; jco1[1] += jy;
 638                 jco2[0] += jx; jco2[1] += jy;
 639                 jco3[0] += jx; jco3[1] += jy;
 640                 jco4[0] += jx; jco4[1] += jy;
 641
 642                 /* XXX mblur? */
 643         }
 644
 645         spart->sample= sample;
 646
 647         spart->t[0]= t-dt;
 648         spart->s[0]= -1.0f;
 649         spart->t[1]= t-dt;
 650         spart->s[1]= 1.0f;
 651         spart->t[2]= t;
 652         spart->s[2]= 1.0f;
 653         zspan_scanconvert_strand(zspan, spart, jco1, jco2, jco3, do_strand_fillac);
 654         spart->t[0]= t-dt;
 655         spart->s[0]= -1.0f;
 656         spart->t[1]= t;
 657         spart->s[1]= 1.0f;
 658         spart->t[2]= t;
 659         spart->s[2]= -1.0f;
 660         zspan_scanconvert_strand(zspan, spart, jco1, jco3, jco4, do_strand_fillac);
 661 }
 662
 663 static void strand_render(Render *re, StrandSegment *sseg, float winmat[4][4], StrandPart *spart, ZSpan *zspan, int totzspan, StrandPoint *p1, StrandPoint *p2)
 664 {
 665         if (spart) {
 666                 float t= p2->t;
 667                 float dt= p2->t - p1->t;
 668                 int a;
 669
 670                 for (a=0; a<spart->samples; a++)
 671                         do_scanconvert_strand(re, spart, zspan, t, dt, p1->zco2, p1->zco1, p2->zco1, p2->zco2, a);
 672         }
 673         else {
 674                 float hoco1[4], hoco2[4];
 675                 int a, obi, index;
 676
 677                 obi= sseg->obi - re->objectinstance;
 678                 index= sseg->strand->index;
 679
 680                 projectvert(p1->co, winmat, hoco1);
 681                 projectvert(p2->co, winmat, hoco2);
 682
 683
 684                 for (a=0; a<totzspan; a++) {
 685 #if 0
 686                         /* render both strand and single pixel wire to counter aliasing */
 687                         zbufclip4(re, &zspan[a], obi, index, p1->hoco2, p1->hoco1, p2->hoco1, p2->hoco2, p1->clip2, p1->clip1, p2->clip1, p2->clip2);
 688 #endif
 689                         /* only render a line for now, which makes the shadow map more
 690                          * similar across frames, and so reduces flicker */
 691                         zbufsinglewire(&zspan[a], obi, index, hoco1, hoco2);
 692                 }
 693         }
 694 }
 695
 696 static int strand_segment_recursive(Render *re, float winmat[4][4], StrandPart *spart, ZSpan *zspan, int totzspan, StrandSegment *sseg, StrandPoint *p1, StrandPoint *p2, int depth)
 697 {
 698         StrandPoint p;
 699         StrandBuffer *buffer= sseg->buffer;
 700         float dot, d1[2], d2[2], len1, len2;
 701
 702         if (depth == buffer->maxdepth)
 703                 return 0;
 704
 705         p.t= (p1->t + p2->t)*0.5f;
 706         strand_eval_point(sseg, &p);
 707         strand_project_point(buffer->winmat, buffer->winx, buffer->winy, &p);
 708
 709         d1[0]= (p.x - p1->x);
 710         d1[1]= (p.y - p1->y);
 711         len1= d1[0]*d1[0] + d1[1]*d1[1];
 712
 713         d2[0]= (p2->x - p.x);
 714         d2[1]= (p2->y - p.y);
 715         len2= d2[0]*d2[0] + d2[1]*d2[1];
 716
 717         if (len1 == 0.0f || len2 == 0.0f)
 718                 return 0;
 719
 720         dot= d1[0]*d2[0] + d1[1]*d2[1];
 721         if (dot*dot > sseg->sqadaptcos*len1*len2)
 722                 return 0;
 723
 724         if (spart) {
 725                 do_strand_point_project(winmat, zspan, p.co1, p.hoco1, p.zco1);
 726                 do_strand_point_project(winmat, zspan, p.co2, p.hoco2, p.zco2);
 727         }
 728         else {
 729 #if 0
 730                 projectvert(p.co1, winmat, p.hoco1);
 731                 projectvert(p.co2, winmat, p.hoco2);
 732                 p.clip1= testclip(p.hoco1);
 733                 p.clip2= testclip(p.hoco2);
 734 #endif
 735         }
 736
 737         if (!strand_segment_recursive(re, winmat, spart, zspan, totzspan, sseg, p1, &p, depth+1))
 738                 strand_render(re, sseg, winmat, spart, zspan, totzspan, p1, &p);
 739         if (!strand_segment_recursive(re, winmat, spart, zspan, totzspan, sseg, &p, p2, depth+1))
 740                 strand_render(re, sseg, winmat, spart, zspan, totzspan, &p, p2);
 741
 742         return 1;
 743 }
 744
 745 void render_strand_segment(Render *re, float winmat[4][4], StrandPart *spart, ZSpan *zspan, int totzspan, StrandSegment *sseg)
 746 {
 747         StrandBuffer *buffer= sseg->buffer;
 748         StrandPoint *p1= &sseg->point1;
 749         StrandPoint *p2= &sseg->point2;
 750
 751         p1->t= 0.0f;
 752         p2->t= 1.0f;
 753
 754         strand_eval_point(sseg, p1);
 755         strand_project_point(buffer->winmat, buffer->winx, buffer->winy, p1);
 756         strand_eval_point(sseg, p2);
 757         strand_project_point(buffer->winmat, buffer->winx, buffer->winy, p2);
 758
 759         if (spart) {
 760                 do_strand_point_project(winmat, zspan, p1->co1, p1->hoco1, p1->zco1);
 761                 do_strand_point_project(winmat, zspan, p1->co2, p1->hoco2, p1->zco2);
 762                 do_strand_point_project(winmat, zspan, p2->co1, p2->hoco1, p2->zco1);
 763                 do_strand_point_project(winmat, zspan, p2->co2, p2->hoco2, p2->zco2);
 764         }
 765         else {
 766 #if 0
 767                 projectvert(p1->co1, winmat, p1->hoco1);
 768                 projectvert(p1->co2, winmat, p1->hoco2);
 769                 projectvert(p2->co1, winmat, p2->hoco1);
 770                 projectvert(p2->co2, winmat, p2->hoco2);
 771                 p1->clip1= testclip(p1->hoco1);
 772                 p1->clip2= testclip(p1->hoco2);
 773                 p2->clip1= testclip(p2->hoco1);
 774                 p2->clip2= testclip(p2->hoco2);
 775 #endif
 776         }
 777
 778         if (!strand_segment_recursive(re, winmat, spart, zspan, totzspan, sseg, p1, p2, 0))
 779                 strand_render(re, sseg, winmat, spart, zspan, totzspan, p1, p2);
 780 }
 781
 782 /* render call to fill in strands */
 783 int zbuffer_strands_abuf(Render *re, RenderPart *pa, APixstrand *apixbuf, ListBase *apsmbase, unsigned int lay, int UNUSED(negzmask), float winmat[4][4], int winx, int winy, int samples, float (*jit)[2], float clipcrop, int shadow, StrandShadeCache *cache)
 784 {
 785         ObjectRen *obr;
 786         ObjectInstanceRen *obi;
 787         ZSpan zspan;
 788         StrandRen *strand = NULL;
 789         StrandVert *svert;
 790         StrandBound *sbound;
 791         StrandPart spart;
 792         StrandSegment sseg;
 793         StrandSortSegment *sortsegments = NULL, *sortseg, *firstseg;
 794         MemArena *memarena;
 795         float z[4], bounds[4], obwinmat[4][4];
 796         int a, b, c, i, totsegment, clip[4];
 797
 798         if (re->test_break(re->tbh))
 799                 return 0;
 800         if (re->totstrand == 0)
 801                 return 0;
 802
 803         /* setup StrandPart */
 804         memset(&spart, 0, sizeof(spart));
 805
 806         spart.re= re;
 807         spart.rectx= pa->rectx;
 808         spart.recty= pa->recty;
 809         spart.apixbuf= apixbuf;
 810         spart.zspan= &zspan;
 811         spart.rectdaps= pa->rectdaps;
 812         spart.rectz= pa->rectz;
 813         spart.rectmask= pa->rectmask;
 814         spart.cache= cache;
 815         spart.shadow= shadow;
 816         spart.jit= jit;
 817         spart.samples= samples;
 818
 819         zbuf_alloc_span(&zspan, pa->rectx, pa->recty, clipcrop);
 820
 821         /* needed for transform from hoco to zbuffer co */
 822         zspan.zmulx= ((float)winx)/2.0f;
 823         zspan.zmuly= ((float)winy)/2.0f;
 824
 825         zspan.zofsx= -pa->disprect.xmin;
 826         zspan.zofsy= -pa->disprect.ymin;
 827
 828         /* to center the sample position */
 829         if (!shadow) {
 830                 zspan.zofsx -= 0.5f;
 831                 zspan.zofsy -= 0.5f;
 832         }
 833
 834         zspan.apsmbase= apsmbase;
 835
 836         /* clipping setup */
 837         bounds[0]= (2*pa->disprect.xmin - winx-1)/(float)winx;
 838         bounds[1]= (2*pa->disprect.xmax - winx+1)/(float)winx;
 839         bounds[2]= (2*pa->disprect.ymin - winy-1)/(float)winy;
 840         bounds[3]= (2*pa->disprect.ymax - winy+1)/(float)winy;
 841
 842         memarena= BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, "strand sort arena");
 843         firstseg= NULL;
 844         totsegment= 0;
 845
 846         /* for all object instances */
 847         for (obi=re->instancetable.first, i=0; obi; obi=obi->next, i++) {
 848                 Material *ma;
 849                 float widthx, widthy;
 850
 851                 obr= obi->obr;
 852
 853                 if (!obr->strandbuf || !(obr->strandbuf->lay & lay))
 854                         continue;
 855
 856                 /* compute matrix and try clipping whole object */
 857                 if (obi->flag & R_TRANSFORMED)
 858                         mul_m4_m4m4(obwinmat, winmat, obi->mat);
 859                 else
 860                         copy_m4_m4(obwinmat, winmat);
 861
 862                 /* test if we should skip it */
 863                 ma = obr->strandbuf->ma;
 864
 865                 if (shadow && !(ma->mode & MA_SHADBUF))
 866                         continue;
 867                 else if (!shadow && (ma->mode & MA_ONLYCAST))
 868                         continue;
 869
 870                 if (clip_render_object(obi->obr->boundbox, bounds, obwinmat))
 871                         continue;
 872
 873                 widthx= obr->strandbuf->maxwidth*obwinmat[0][0];
 874                 widthy= obr->strandbuf->maxwidth*obwinmat[1][1];
 875
 876                 /* for each bounding box containing a number of strands */
 877                 sbound= obr->strandbuf->bound;
 878                 for (c=0; c<obr->strandbuf->totbound; c++, sbound++) {
 879                         if (clip_render_object(sbound->boundbox, bounds, obwinmat))
 880                                 continue;
 881
 882                         /* for each strand in this bounding box */
 883                         for (a=sbound->start; a<sbound->end; a++) {
 884                                 strand= RE_findOrAddStrand(obr, a);
 885                                 svert= strand->vert;
 886
 887                                 /* keep clipping and z depth for 4 control points */
 888                                 clip[1]= strand_test_clip(obwinmat, &zspan, bounds, svert->co, &z[1], widthx, widthy);
 889                                 clip[2]= strand_test_clip(obwinmat, &zspan, bounds, (svert+1)->co, &z[2], widthx, widthy);
 890                                 clip[0]= clip[1]; z[0]= z[1];
 891
 892                                 for (b=0; b<strand->totvert-1; b++, svert++) {
 893                                         /* compute 4th point clipping and z depth */
 894                                         if (b < strand->totvert-2) {
 895                                                 clip[3]= strand_test_clip(obwinmat, &zspan, bounds, (svert+2)->co, &z[3], widthx, widthy);
 896                                         }
 897                                         else {
 898                                                 clip[3]= clip[2]; z[3]= z[2];
 899                                         }
 900
 901                                         /* check clipping and add to sortsegments buffer */
 902                                         if (!(clip[0] & clip[1] & clip[2] & clip[3])) {
 903                                                 sortseg= BLI_memarena_alloc(memarena, sizeof(StrandSortSegment));
 904                                                 sortseg->obi= i;
 905                                                 sortseg->strand= strand->index;
 906                                                 sortseg->segment= b;
 907
 908                                                 sortseg->z= 0.5f*(z[1] + z[2]);
 909
 910                                                 sortseg->next= firstseg;
 911                                                 firstseg= sortseg;
 912                                                 totsegment++;
 913                                         }
 914
 915                                         /* shift clipping and z depth */
 916                                         clip[0]= clip[1]; z[0]= z[1];
 917                                         clip[1]= clip[2]; z[1]= z[2];
 918                                         clip[2]= clip[3]; z[2]= z[3];
 919                                 }
 920                         }
 921                 }
 922         }
 923
 924         if (!re->test_break(re->tbh)) {
 925                 /* convert list to array and sort */
 926                 sortsegments= MEM_mallocN(sizeof(StrandSortSegment)*totsegment, "StrandSortSegment");
 927                 for (a=0, sortseg=firstseg; a<totsegment; a++, sortseg=sortseg->next)
 928                         sortsegments[a]= *sortseg;
 929                 qsort(sortsegments, totsegment, sizeof(StrandSortSegment), compare_strand_segment);
 930         }
 931
 932         BLI_memarena_free(memarena);
 933
 934         spart.totapixbuf= MEM_callocN(sizeof(int)*pa->rectx*pa->recty, "totapixbuf");
 935
 936         if (!re->test_break(re->tbh)) {
 937                 /* render segments in sorted order */
 938                 sortseg= sortsegments;
 939                 for (a=0; a<totsegment; a++, sortseg++) {
 940                         if (re->test_break(re->tbh))
 941                                 break;
 942
 943                         obi= &re->objectinstance[sortseg->obi];
 944                         obr= obi->obr;
 945
 946                         sseg.obi= obi;
 947                         sseg.strand= RE_findOrAddStrand(obr, sortseg->strand);
 948                         sseg.buffer= sseg.strand->buffer;
 949                         sseg.sqadaptcos= sseg.buffer->adaptcos;
 950                         sseg.sqadaptcos *= sseg.sqadaptcos;
 951
 952                         svert= sseg.strand->vert + sortseg->segment;
 953                         sseg.v[0]= (sortseg->segment > 0)? (svert-1): svert;
 954                         sseg.v[1]= svert;
 955                         sseg.v[2]= svert+1;
 956                         sseg.v[3]= (sortseg->segment < sseg.strand->totvert-2)? svert+2: svert+1;
 957                         sseg.shaded= 0;
 958
 959                         spart.segment= &sseg;
 960
 961                         render_strand_segment(re, winmat, &spart, &zspan, 1, &sseg);
 962                 }
 963         }
 964
 965         if (sortsegments)
 966                 MEM_freeN(sortsegments);
 967         MEM_freeN(spart.totapixbuf);
 968
 969         zbuf_free_span(&zspan);
 970
 971         return totsegment;
 972 }
 973
 974 /* *************** */
 975
 976 StrandSurface *cache_strand_surface(Render *re, ObjectRen *obr, DerivedMesh *dm, float mat[4][4], int timeoffset)
 977 {
 978         StrandSurface *mesh;
 979         MFace *mface;
 980         MVert *mvert;
 981         float (*co)[3];
 982         int a, totvert, totface;
 983
 984         totvert= dm->getNumVerts(dm);
 985         totface= dm->getNumTessFaces(dm);
 986
 987         for (mesh = re->strandsurface.first; mesh; mesh = mesh->next) {
 988                 if ((mesh->obr.ob    == obr->ob) &&
 989                     (mesh->obr.par   == obr->par) &&
 990                     (mesh->obr.index == obr->index) &&
 991                     (mesh->totvert   == totvert) &&
 992                     (mesh->totface   == totface))
 993                 {
 994                         break;
 995                 }
 996         }
 997
 998         if (!mesh) {
 999                 mesh= MEM_callocN(sizeof(StrandSurface), "StrandSurface");
1000                 mesh->obr= *obr;
1001                 mesh->totvert= totvert;
1002                 mesh->totface= totface;
1003                 mesh->face= MEM_callocN(sizeof(int)*4*mesh->totface, "StrandSurfFaces");
1004                 mesh->ao= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfAO");
1005                 mesh->env= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfEnv");
1006                 mesh->indirect= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfIndirect");
1007                 BLI_addtail(&re->strandsurface, mesh);
1008         }
1009
1010         if (timeoffset == -1 && !mesh->prevco)
1011                 mesh->prevco= co= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfCo");
1012         else if (timeoffset == 0 && !mesh->co)
1013                 mesh->co= co= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfCo");
1014         else if (timeoffset == 1 && !mesh->nextco)
1015                 mesh->nextco= co= MEM_callocN(sizeof(float)*3*mesh->totvert, "StrandSurfCo");
1016         else
1017                 return mesh;
1018
1019         mvert= dm->getVertArray(dm);
1020         for (a=0; a<mesh->totvert; a++, mvert++) {
1021                 copy_v3_v3(co[a], mvert->co);
1022                 mul_m4_v3(mat, co[a]);
1023         }
1024
1025         mface= dm->getTessFaceArray(dm);
1026         for (a=0; a<mesh->totface; a++, mface++) {
1027                 mesh->face[a][0]= mface->v1;
1028                 mesh->face[a][1]= mface->v2;
1029                 mesh->face[a][2]= mface->v3;
1030                 mesh->face[a][3]= mface->v4;
1031         }
1032
1033         return mesh;
1034 }
1035
1036 void free_strand_surface(Render *re)
1037 {
1038         StrandSurface *mesh;
1039
1040         for (mesh=re->strandsurface.first; mesh; mesh=mesh->next) {
1041                 if (mesh->co) MEM_freeN(mesh->co);
1042                 if (mesh->prevco) MEM_freeN(mesh->prevco);
1043                 if (mesh->nextco) MEM_freeN(mesh->nextco);
1044                 if (mesh->ao) MEM_freeN(mesh->ao);
1045                 if (mesh->env) MEM_freeN(mesh->env);
1046                 if (mesh->indirect) MEM_freeN(mesh->indirect);
1047                 if (mesh->face) MEM_freeN(mesh->face);
1048         }
1049
1050         BLI_freelistN(&re->strandsurface);
1051 }
1052
1053 void strand_minmax(StrandRen *strand, float min[3], float max[3], const float width)
1054 {
1055         StrandVert *svert;
1056         const float width2 = width * 2.0f;
1057         float vec[3];
1058         int a;
1059
1060         for (a=0, svert=strand->vert; a<strand->totvert; a++, svert++) {
1061                 copy_v3_v3(vec, svert->co);
1062                 minmax_v3v3_v3(min, max, vec);
1063
1064                 if (width!=0.0f) {
1065                         add_v3_fl(vec, width);
1066                         minmax_v3v3_v3(min, max, vec);
1067                         add_v3_fl(vec, -width2);
1068                         minmax_v3v3_v3(min, max, vec);
1069                 }
1070         }
1071 }
1072