src/rrts.cc

   1 #include <algorithm>
   2 #include "rrts.h"
   3
   4 #include "reeds_shepp.h"
   5
   6 template <typename T> int sgn(T val) {
   7         return (T(0) < val) - (val < T(0));
   8 }
   9
  10 RRTNode::RRTNode()
  11 {
  12 }
  13
  14 RRTNode::RRTNode(const BicycleCar &bc)
  15 {
  16     this->x(bc.x());
  17     this->y(bc.y());
  18     this->h(bc.h());
  19     this->sp(bc.sp());
  20     this->st(bc.st());
  21 }
  22
  23 bool RRTNode::operator==(const RRTNode& n)
  24 {
  25         if (this == &n)
  26                 return true;
  27         return false;
  28 }
  29
  30 Obstacle::Obstacle()
  31 {
  32 }
  33
  34 double RRTS::elapsed()
  35 {
  36         std::chrono::duration<double> dt;
  37         dt = std::chrono::duration_cast<std::chrono::duration<double>>(
  38                 std::chrono::high_resolution_clock::now()
  39                 - this->tstart_
  40         );
  41         this->scnt_ = dt.count();
  42         return this->scnt_;
  43 }
  44
  45 void RRTS::log_path_cost()
  46 {
  47         this->log_path_cost_.push_back(cc(this->goals().front()));
  48         this->log_path_time_ += 0.1;
  49 }
  50
  51 bool RRTS::should_stop()
  52 {
  53         // the following counters must be updated, do not comment
  54         this->icnt_++;
  55         this->elapsed();
  56         // current iteration stop conditions
  57         if (this->should_finish()) return true;
  58         if (this->should_break()) return true;
  59         // but continue by default
  60         return false;
  61 }
  62
  63 bool RRTS::should_finish()
  64 {
  65         // decide finish conditions (maybe comment some lines)
  66         //if (this->icnt_ > 999) return true;
  67         if (this->scnt_ > 2) return true;
  68         //if (this->gf()) return true;
  69         // but continue by default
  70         return false;
  71 }
  72
  73 bool RRTS::should_break()
  74 {
  75         // decide break conditions (maybe comment some lines)
  76         //if (this->scnt_ - this->pcnt_ > 2) return true;
  77         // but continue by default
  78         return false;
  79 }
  80
  81 bool RRTS::should_continue()
  82 {
  83         // decide the stop conditions (maybe comment some lines)
  84         // it is exact opposite of `should_stop`
  85         //if (this->icnt_ > 999) return false;
  86         if (this->scnt_ > 10) return false;
  87         if (this->gf()) return false;
  88         // and reset pause counter if should continue
  89         this->pcnt_ = this->scnt_;
  90         return true;
  91 }
  92
  93 void RRTS::store_node(RRTNode n)
  94 {
  95         this->nodes().push_back(n);
  96 }
  97
  98 // RRT procedures
  99 std::tuple<bool, unsigned int, unsigned int>
 100 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
 101 {
 102         for (auto &o: this->obstacles())
 103                 if (std::get<0>(::collide(poly, o.poly())))
 104                         return ::collide(poly, o.poly());
 105         return std::make_tuple(false, 0, 0);
 106 }
 107
 108 std::tuple<bool, unsigned int, unsigned int>
 109 RRTS::collide_steered_from(RRTNode &f)
 110 {
 111         auto fbc = BicycleCar();
 112         fbc.x(f.x());
 113         fbc.y(f.y());
 114         fbc.h(f.h());
 115         std::vector<std::tuple<double, double>> s;
 116         s.push_back(std::make_tuple(fbc.x(), fbc.y()));
 117         for (auto &n: this->steered()) {
 118                 auto nbc = BicycleCar();
 119                 nbc.x(n.x());
 120                 nbc.y(n.y());
 121                 nbc.h(n.h());
 122                 s.push_back(std::make_tuple(nbc.lfx(), nbc.lfy()));
 123                 s.push_back(std::make_tuple(nbc.lrx(), nbc.lry()));
 124                 s.push_back(std::make_tuple(nbc.rrx(), nbc.rry()));
 125                 s.push_back(std::make_tuple(nbc.rfx(), nbc.rfy()));
 126         }
 127         auto col = this->collide(s);
 128         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 129         if (std::get<0>(col) && strip_from > 0) {
 130                 while (strip_from-- > 0) {
 131                         this->steered().pop_back();
 132                 }
 133                 return this->collide_steered_from(f);
 134         }
 135         return col;
 136 }
 137
 138 std::tuple<bool, unsigned int, unsigned int>
 139 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 140 {
 141         auto fbc = BicycleCar();
 142         fbc.x(f.x());
 143         fbc.y(f.y());
 144         fbc.h(f.h());
 145         auto tbc = BicycleCar();
 146         tbc.x(f.x());
 147         tbc.y(f.y());
 148         tbc.h(f.h());
 149         std::vector<std::tuple<double, double>> p;
 150         p.push_back(std::make_tuple(fbc.lfx(), fbc.lfy()));
 151         p.push_back(std::make_tuple(fbc.lrx(), fbc.lry()));
 152         p.push_back(std::make_tuple(fbc.rrx(), fbc.rry()));
 153         p.push_back(std::make_tuple(fbc.rfx(), fbc.rfy()));
 154         p.push_back(std::make_tuple(tbc.lfx(), tbc.lfy()));
 155         p.push_back(std::make_tuple(tbc.lrx(), tbc.lry()));
 156         p.push_back(std::make_tuple(tbc.rrx(), tbc.rry()));
 157         p.push_back(std::make_tuple(tbc.rfx(), tbc.rfy()));
 158         return this->collide(p);
 159 }
 160
 161 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 162 {
 163         double cost = 0;
 164         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 165         return cost;
 166 }
 167
 168 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 169 {
 170         double cost = 0;
 171         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 172         return cost;
 173 }
 174
 175 void RRTS::sample()
 176 {
 177         double x = 0;
 178         double y = 0;
 179         double h = 0;
 180         switch (this->sample_dist_type()) {
 181         case 1: // uniform
 182                 x = this->udx_(this->gen_);
 183                 y = this->udy_(this->gen_);
 184                 h = this->udh_(this->gen_);
 185                 break;
 186         case 2: // uniform circle
 187         {
 188                 // see https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly/50746409#50746409
 189                 double R = sqrt(
 190                         pow(
 191                                 this->nodes().front().x()
 192                                 - this->goals().front().x(),
 193                                 2
 194                         )
 195                         + pow(
 196                                 this->nodes().front().y()
 197                                 - this->goals().front().y(),
 198                                 2
 199                         )
 200                 );
 201                 double a = atan2(
 202                         this->goals().front().y() - this->nodes().front().y(),
 203                         this->goals().front().x() - this->nodes().front().x()
 204                 );
 205                 double cx = this->goals().front().x() + R/2 * cos(a);
 206                 double cy = this->goals().front().y() + R/2 * sin(a);
 207                 double r = R * sqrt(this->udx_(this->gen_));
 208                 double theta = this->udy_(this->gen_) * 2 * M_PI;
 209                 x = cx + r * cos(theta);
 210                 y = cy + r * sin(theta);
 211                 h = this->udh_(this->gen_);
 212         }
 213                 break;
 214         case 3: {
 215                 this->udi_ = std::uniform_int_distribution<unsigned int>(
 216                         0,
 217                         this->nodes().size() - 1
 218                 );
 219                 auto ind = this->udi_(this->gen_);
 220                 auto n = this->nodes()[ind];
 221                 x = n.x();
 222                 y = n.y();
 223                 h = n.h();
 224                 break;
 225                 }
 226         default: // normal
 227                 x = this->ndx_(this->gen_);
 228                 y = this->ndy_(this->gen_);
 229                 h = this->ndh_(this->gen_);
 230         }
 231         this->samples().push_back(RRTNode());
 232         this->samples().back().x(x);
 233         this->samples().back().y(y);
 234         this->samples().back().h(h);
 235 }
 236
 237 RRTNode *RRTS::nn(RRTNode &t)
 238 {
 239         RRTNode *nn = &this->nodes().front();
 240         double cost = this->cost_search(*nn, t);
 241         for (auto &f: this->nodes()) {
 242                 if (this->cost_search(f, t) < cost) {
 243                         nn = &f;
 244                         cost = this->cost_search(f, t);
 245                 }
 246         }
 247         return nn;
 248 }
 249
 250 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 251 {
 252         std::vector<RRTNode *> nv;
 253         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 254         for (auto &f: this->nodes())
 255                 if (this->cost_search(f, t) < cost)
 256                         nv.push_back(&f);
 257         return nv;
 258 }
 259
 260 int cb_rs_steer(double q[4], void *user_data)
 261 {
 262         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 263         RRTNode *ln = nullptr;
 264         if (nodes->size() > 0)
 265                 ln = &nodes->back();
 266         nodes->push_back(RRTNode());
 267         nodes->back().x(q[0]);
 268         nodes->back().y(q[1]);
 269         nodes->back().h(q[2]);
 270         nodes->back().sp(q[3]);
 271         if (nodes->back().sp() == 0)
 272                 nodes->back().set_t(RRTNodeType::cusp);
 273         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 274                 ln->set_t(RRTNodeType::cusp);
 275         return 0;
 276 }
 277
 278 void RRTS::steer(RRTNode &f, RRTNode &t)
 279 {
 280         this->steered().clear();
 281         double q0[] = {f.x(), f.y(), f.h()};
 282         double q1[] = {t.x(), t.y(), t.h()};
 283         ReedsSheppStateSpace rsss(this->bc.mtr());
 284         rsss.sample(q0, q1, 0.05, cb_rs_steer, &this->steered());
 285 }
 286
 287 void RRTS::steer1(RRTNode &f, RRTNode &t)
 288 {
 289     return this->steer(f, t);
 290 }
 291
 292 void RRTS::steer2(RRTNode &f, RRTNode &t)
 293 {
 294     return this->steer(f, t);
 295 }
 296
 297 void RRTS::join_steered(RRTNode *f)
 298 {
 299         while (this->steered().size() > 0) {
 300                 this->store_node(this->steered().front());
 301                 RRTNode *t = &this->nodes().back();
 302                 t->p(f);
 303                 t->c(this->cost_build(*f, *t));
 304                 this->steered().erase(this->steered().begin());
 305                 f = t;
 306         }
 307 }
 308
 309 bool RRTS::goal_found(RRTNode &f)
 310 {
 311         auto &g = this->goals().front();
 312         double cost = this->cost_build(f, g);
 313         double edist = sqrt(
 314                 pow(f.x() - g.x(), 2)
 315                 + pow(f.y() - g.y(), 2)
 316         );
 317         double adist = std::abs(f.h() - g.h());
 318         if (edist < 0.05 && adist < M_PI / 32) {
 319                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 320                         g.p(&f);
 321                         g.c(cost);
 322                 }
 323                 return true;
 324         }
 325         return false;
 326 }
 327
 328 // RRT* procedures
 329 bool RRTS::connect()
 330 {
 331         RRTNode *t = &this->steered().front();
 332         RRTNode *f = this->nn(this->samples().back());
 333         double cost = this->cost_search(*f, *t);
 334         for (auto n: this->nv(*t)) {
 335                 if (
 336                         !std::get<0>(this->collide_two_nodes(*n, *t))
 337                         && this->cost_search(*n, *t) < cost
 338                 ) {
 339                         f = n;
 340                         cost = this->cost_search(*n, *t);
 341                 }
 342         }
 343         this->store_node(this->steered().front());
 344         t = &this->nodes().back();
 345         t->p(f);
 346         t->c(this->cost_build(*f, *t));
 347         t->set_t(RRTNodeType::connected);
 348         return true;
 349 }
 350
 351 void RRTS::rewire()
 352 {
 353         RRTNode *f = &this->nodes().back();
 354         for (auto n: this->nv(*f)) {
 355                 if (
 356                         !std::get<0>(this->collide_two_nodes(*f, *n))
 357                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 358                 ) {
 359                         n->p(f);
 360                         n->c(this->cost_build(*f, *n));
 361                 }
 362         }
 363 }
 364
 365 // API
 366 void RRTS::init()
 367 {
 368 }
 369
 370 void RRTS::deinit()
 371 {
 372         this->nodes().clear();
 373         this->samples().clear();
 374         this->steered().clear();
 375         this->store_node(RRTNode()); // root
 376         this->icnt_ = 0;
 377         this->scnt_ = 0;
 378         this->pcnt_ = 0;
 379         this->gf_ = false;
 380 }
 381
 382 std::vector<RRTNode *> RRTS::path()
 383 {
 384         std::vector<RRTNode *> path;
 385         if (this->goals().size() == 0)
 386                 return path;
 387         RRTNode *goal = &this->goals().back();
 388         if (goal->p() == nullptr)
 389                 return path;
 390         while (goal != nullptr) {
 391                 path.push_back(goal);
 392                 goal = goal->p();
 393         }
 394         std::reverse(path.begin(), path.end());
 395         return path;
 396 }
 397
 398 bool RRTS::next()
 399 {
 400         if (this->icnt_ == 0)
 401                 this->tstart_ = std::chrono::high_resolution_clock::now();
 402         bool next = true;
 403         if (this->scnt_ > this->log_path_time_)
 404             this->log_path_cost();
 405         if (this->should_stop())
 406                 return false;
 407         if (this->samples().size() == 0) {
 408                 this->samples().push_back(RRTNode());
 409                 this->samples().back().x(this->goals().front().x());
 410                 this->samples().back().y(this->goals().front().y());
 411                 this->samples().back().h(this->goals().front().h());
 412         } else {
 413                 this->sample();
 414         }
 415         this->steer1(
 416                 *this->nn(this->samples().back()),
 417                 this->samples().back()
 418         );
 419         if (this->steered().size() == 0)
 420                 return next;
 421         auto col = this->collide_steered_from(
 422                 *this->nn(this->samples().back())
 423         );
 424         if (std::get<0>(col)) {
 425                 auto rcnt = this->steered().size() - std::get<1>(col);
 426                 while (rcnt-- > 0) {
 427                         this->steered().pop_back();
 428                 }
 429         }
 430         if (!this->connect())
 431                 return next;
 432         this->rewire();
 433         unsigned scnt = this->steered().size();
 434         this->join_steered(&this->nodes().back());
 435         RRTNode *just_added = &this->nodes().back();
 436         while (scnt > 0) {
 437                 scnt--;
 438                 auto &g = this->goals().front();
 439                 this->steer2(*just_added, g);
 440                 if (std::get<0>(this->collide_steered_from(
 441                         *just_added
 442                 )))
 443                         continue;
 444                 this->join_steered(just_added);
 445                 this->gf(this->goal_found(this->nodes().back()));
 446                 just_added = just_added->p();
 447         }
 448         return next;
 449 }
 450
 451 void RRTS::set_sample_normal(
 452         double mx, double dx,
 453         double my, double dy,
 454         double mh, double dh
 455 )
 456 {
 457         this->ndx_ = std::normal_distribution<double>(mx, dx);
 458         this->ndy_ = std::normal_distribution<double>(my, dy);
 459         this->ndh_ = std::normal_distribution<double>(mh, dh);
 460 }
 461 void RRTS::set_sample_uniform(
 462         double xmin, double xmax,
 463         double ymin, double ymax,
 464         double hmin, double hmax
 465 )
 466 {
 467         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 468         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 469         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 470 }
 471 void RRTS::set_sample_uniform_circle()
 472 {
 473         this->udx_ = std::uniform_real_distribution<double>(0, 1);
 474         this->udy_ = std::uniform_real_distribution<double>(0, 1);
 475         this->udh_ = std::uniform_real_distribution<double>(0, 2 * M_PI);
 476 }
 477 void RRTS::set_sample(
 478         double x1, double x2,
 479         double y1, double y2,
 480         double h1, double h2
 481 )
 482 {
 483         switch (this->sample_dist_type()) {
 484         case 1: // uniform
 485                 x1 += this->nodes().front().x();
 486                 x2 += this->nodes().front().x();
 487                 y1 += this->nodes().front().y();
 488                 y2 += this->nodes().front().y();
 489                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 490                 break;
 491         case 2: // uniform circle
 492                 this->set_sample_uniform_circle();
 493                 break;
 494         case 3: // uniform index of node in nodes
 495                 this->set_sample_uniform_circle();
 496                 break;
 497         default: // normal
 498                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 499         }
 500 }
 501
 502 Json::Value RRTS::json()
 503 {
 504         Json::Value jvo;
 505         {
 506                 jvo["time"] = this->scnt();
 507         }
 508         {
 509                 jvo["iterations"] = this->icnt();
 510         }
 511         {
 512                 jvo["init"][0] = this->nodes().front().x();
 513                 jvo["init"][1] = this->nodes().front().y();
 514                 jvo["init"][2] = this->nodes().front().h();
 515         }
 516         {
 517                 jvo["path_cost_before_opt"] = this->path_cost_before_opt_;
 518         }
 519         {
 520                 if (this->path().size() > 0) {
 521                         jvo["cost"] = cc(*this->path().back());
 522                         jvo["entry"][0] = this->goals().front().x();
 523                         jvo["entry"][1] = this->goals().front().y();
 524                         jvo["entry"][2] = this->goals().front().h();
 525                         jvo["goal"][0] = this->goals().back().x();
 526                         jvo["goal"][1] = this->goals().back().y();
 527                         jvo["goal"][2] = this->goals().back().h();
 528                 }
 529         }
 530         {
 531                 unsigned int cu = 0;
 532                 unsigned int co = 0;
 533                 unsigned int pcnt = 0;
 534                 for (auto n: this->path()) {
 535                         jvo["path"][pcnt][0] = n->x();
 536                         jvo["path"][pcnt][1] = n->y();
 537                         jvo["path"][pcnt][2] = n->h();
 538                         if (n->t(RRTNodeType::cusp))
 539                                 cu++;
 540                         if (n->t(RRTNodeType::connected))
 541                                 co++;
 542                         pcnt++;
 543                 }
 544                 jvo["cusps-in-path"] = cu;
 545                 jvo["connecteds-in-path"] = co;
 546         }
 547         {
 548                 unsigned int gcnt = 0;
 549                 for (auto g: this->goals()) {
 550                         jvo["goals"][gcnt][0] = g.x();
 551                         jvo["goals"][gcnt][1] = g.y();
 552                         jvo["goals"][gcnt][2] = g.h();
 553                         gcnt++;
 554                 }
 555         }
 556         {
 557                 unsigned int ocnt = 0;
 558                 for (auto o: this->obstacles()) {
 559                         unsigned int ccnt = 0;
 560                         for (auto c: o.poly()) {
 561                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 562                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 563                                 ccnt++;
 564                         }
 565                         ocnt++;
 566                 }
 567         }
 568         {
 569                 jvo["nodes"] = (unsigned int) this->nodes().size();
 570         }
 571         {
 572                 unsigned int cnt = 0;
 573                 for (auto i: this->log_path_cost_)
 574                         jvo["log_path_cost"][cnt++] = i;
 575         }
 576         //{
 577         //        unsigned int ncnt = 0;
 578         //        for (auto n: this->nodes()) {
 579         //                jvo["nodes_x"][ncnt] = n.x();
 580         //                jvo["nodes_y"][ncnt] = n.y();
 581         //                //jvo["nodes_h"][ncnt] = n.h();
 582         //                ncnt++;
 583         //        }
 584         //}
 585         return jvo;
 586 }
 587
 588 void RRTS::json(Json::Value jvi)
 589 {
 590         assert(jvi["init"] != Json::nullValue);
 591         assert(jvi["goals"] != Json::nullValue);
 592         assert(jvi["obst"] != Json::nullValue);
 593
 594         this->nodes().front().x(jvi["init"][0].asDouble());
 595         this->nodes().front().y(jvi["init"][1].asDouble());
 596         this->nodes().front().h(jvi["init"][2].asDouble());
 597         {
 598                 RRTNode* gp = nullptr;
 599                 if (jvi["entry"] != Json::nullValue) {
 600                         this->entry_set = true;
 601                         this->entry.x = jvi["entry"][0].asDouble();
 602                         this->entry.y = jvi["entry"][1].asDouble();
 603                         this->entry.b = jvi["entry"][2].asDouble();
 604                         this->entry.e = jvi["entry"][3].asDouble();
 605                         RRTNode tmp_node;
 606                         tmp_node.x(this->entry.x);
 607                         tmp_node.y(this->entry.y);
 608                         tmp_node.h((this->entry.b + this->entry.e) / 2.0);
 609                         this->goals().push_back(tmp_node);
 610                         this->goals().back().p(gp);
 611                         gp = &this->goals().back();
 612                 }
 613                 for (auto g: jvi["goals"]) {
 614                         RRTNode tmp_node;
 615                         tmp_node.x(g[0].asDouble());
 616                         tmp_node.y(g[1].asDouble());
 617                         tmp_node.h(g[2].asDouble());
 618                         this->goals().push_back(tmp_node);
 619                         this->goals().back().p(gp);
 620                         gp = &this->goals().back();
 621                 }
 622                 this->goals().front().set_t(RRTNodeType::cusp);
 623                 this->goals().back().set_t(RRTNodeType::cusp);
 624         }
 625         {
 626                 Obstacle tmp_obstacle;
 627                 for (auto o: jvi["obst"]) {
 628                         tmp_obstacle.poly().clear();
 629                         for (auto c: o) {
 630                                 double tmp_x = c[0].asDouble();
 631                                 double tmp_y = c[1].asDouble();
 632                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 633                                 tmp_obstacle.poly().push_back(tmp_tuple);
 634                         }
 635                         this->obstacles().push_back(tmp_obstacle);
 636                 }
 637         }
 638         {
 639                 double edist_init_goal = sqrt(
 640                         pow(
 641                                 this->nodes().front().x()
 642                                 - this->goals().front().x(),
 643                                 2
 644                         )
 645                         + pow(
 646                                 this->nodes().front().y()
 647                                 - this->goals().front().y(),
 648                                 2
 649                         )
 650                 );
 651                 this->set_sample(
 652                         this->nodes().front().x(), edist_init_goal,
 653                         this->nodes().front().y(), edist_init_goal,
 654                         0, 2 * M_PI
 655                 );
 656         }
 657 }
 658
 659 RRTS::RRTS()
 660         : gen_(std::random_device{}())
 661 {
 662         this->goals().reserve(100);
 663         this->nodes().reserve(4000000);
 664         this->samples().reserve(1000);
 665         this->steered().reserve(20000);
 666         this->store_node(RRTNode()); // root
 667 }
 668
 669 double cc(RRTNode &t)
 670 {
 671         RRTNode *n = &t;
 672         double cost = 0;
 673         while (n != nullptr) {
 674                 cost += n->c();
 675                 n = n->p();
 676         }
 677         return cost;
 678 }