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->finishit) return true;
  69         //if (this->gf()) return true;
  70         // but continue by default
  71         return false;
  72 }
  73
  74 bool RRTS::should_break()
  75 {
  76         // decide break conditions (maybe comment some lines)
  77         //if (this->scnt_ - this->pcnt_ > 2) return true;
  78         // but continue by default
  79         return false;
  80 }
  81
  82 bool RRTS::should_continue()
  83 {
  84         // decide the stop conditions (maybe comment some lines)
  85         // it is exact opposite of `should_stop`
  86         //if (this->icnt_ > 999) return false;
  87         if (this->scnt_ > 10) return false;
  88         if (this->gf()) return false;
  89         // and reset pause counter if should continue
  90         this->pcnt_ = this->scnt_;
  91         return true;
  92 }
  93
  94 void RRTS::store_node(RRTNode n)
  95 {
  96         this->nodes().push_back(n);
  97 }
  98
  99 // RRT procedures
 100 std::tuple<bool, unsigned int, unsigned int>
 101 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
 102 {
 103         for (auto &o: this->obstacles())
 104                 if (std::get<0>(::collide(poly, o.poly())))
 105                         return ::collide(poly, o.poly());
 106         return std::make_tuple(false, 0, 0);
 107 }
 108
 109 std::tuple<bool, unsigned int, unsigned int>
 110 RRTS::collide_steered_from(RRTNode &f)
 111 {
 112         auto fbc = BicycleCar();
 113         fbc.x(f.x());
 114         fbc.y(f.y());
 115         fbc.h(f.h());
 116         std::vector<std::tuple<double, double>> s;
 117         s.push_back(std::make_tuple(fbc.x(), fbc.y()));
 118         for (auto &n: this->steered()) {
 119                 auto nbc = BicycleCar();
 120                 nbc.x(n.x());
 121                 nbc.y(n.y());
 122                 nbc.h(n.h());
 123                 s.push_back(std::make_tuple(nbc.lfx(), nbc.lfy()));
 124                 s.push_back(std::make_tuple(nbc.lrx(), nbc.lry()));
 125                 s.push_back(std::make_tuple(nbc.rrx(), nbc.rry()));
 126                 s.push_back(std::make_tuple(nbc.rfx(), nbc.rfy()));
 127         }
 128         auto col = this->collide(s);
 129         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 130         if (std::get<0>(col) && strip_from > 0) {
 131                 while (strip_from-- > 0) {
 132                         this->steered().pop_back();
 133                 }
 134                 return this->collide_steered_from(f);
 135         }
 136         return col;
 137 }
 138
 139 std::tuple<bool, unsigned int, unsigned int>
 140 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 141 {
 142         auto fbc = BicycleCar();
 143         fbc.x(f.x());
 144         fbc.y(f.y());
 145         fbc.h(f.h());
 146         auto tbc = BicycleCar();
 147         tbc.x(f.x());
 148         tbc.y(f.y());
 149         tbc.h(f.h());
 150         std::vector<std::tuple<double, double>> p;
 151         p.push_back(std::make_tuple(fbc.lfx(), fbc.lfy()));
 152         p.push_back(std::make_tuple(fbc.lrx(), fbc.lry()));
 153         p.push_back(std::make_tuple(fbc.rrx(), fbc.rry()));
 154         p.push_back(std::make_tuple(fbc.rfx(), fbc.rfy()));
 155         p.push_back(std::make_tuple(tbc.lfx(), tbc.lfy()));
 156         p.push_back(std::make_tuple(tbc.lrx(), tbc.lry()));
 157         p.push_back(std::make_tuple(tbc.rrx(), tbc.rry()));
 158         p.push_back(std::make_tuple(tbc.rfx(), tbc.rfy()));
 159         return this->collide(p);
 160 }
 161
 162 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 163 {
 164         double cost = 0;
 165         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 166         return cost;
 167 }
 168
 169 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 170 {
 171         double cost = 0;
 172         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 173         return cost;
 174 }
 175
 176 void RRTS::sample()
 177 {
 178         double x = 0;
 179         double y = 0;
 180         double h = 0;
 181         switch (this->sample_dist_type()) {
 182         case 1: // uniform
 183                 x = this->udx_(this->gen_);
 184                 y = this->udy_(this->gen_);
 185                 h = this->udh_(this->gen_);
 186                 break;
 187         case 2: // uniform circle
 188         {
 189                 // see https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly/50746409#50746409
 190                 double R = sqrt(
 191                         pow(
 192                                 this->nodes().front().x()
 193                                 - this->goals().front().x(),
 194                                 2
 195                         )
 196                         + pow(
 197                                 this->nodes().front().y()
 198                                 - this->goals().front().y(),
 199                                 2
 200                         )
 201                 );
 202                 double a = atan2(
 203                         this->goals().front().y() - this->nodes().front().y(),
 204                         this->goals().front().x() - this->nodes().front().x()
 205                 );
 206                 double cx = this->goals().front().x() - R/2 * cos(a);
 207                 double cy = this->goals().front().y() - R/2 * sin(a);
 208                 double r = R * sqrt(this->udx_(this->gen_));
 209                 double theta = this->udy_(this->gen_) * 2 * M_PI;
 210                 x = cx + r * cos(theta);
 211                 y = cy + r * sin(theta);
 212                 h = this->udh_(this->gen_);
 213         }
 214                 break;
 215         case 3: {
 216                 this->udi_ = std::uniform_int_distribution<unsigned int>(
 217                         0,
 218                         this->nodes().size() - 1
 219                 );
 220                 auto ind = this->udi_(this->gen_);
 221                 auto n = this->nodes()[ind];
 222                 x = n.x();
 223                 y = n.y();
 224                 h = n.h();
 225                 break;
 226                 }
 227         default: // normal
 228                 x = this->ndx_(this->gen_);
 229                 y = this->ndy_(this->gen_);
 230                 h = this->ndh_(this->gen_);
 231         }
 232         this->samples().push_back(RRTNode());
 233         this->samples().back().x(x);
 234         this->samples().back().y(y);
 235         this->samples().back().h(h);
 236 }
 237
 238 RRTNode *RRTS::nn(RRTNode &t)
 239 {
 240         RRTNode *nn = &this->nodes().front();
 241         double cost = this->cost_search(*nn, t);
 242         for (auto &f: this->nodes()) {
 243                 if (this->cost_search(f, t) < cost) {
 244                         nn = &f;
 245                         cost = this->cost_search(f, t);
 246                 }
 247         }
 248         return nn;
 249 }
 250
 251 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 252 {
 253         std::vector<RRTNode *> nv;
 254         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 255         for (auto &f: this->nodes())
 256                 if (this->cost_search(f, t) < cost)
 257                         nv.push_back(&f);
 258         return nv;
 259 }
 260
 261 int cb_rs_steer(double q[4], void *user_data)
 262 {
 263         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 264         nodes->push_back(RRTNode());
 265         nodes->back().x(q[0]);
 266         nodes->back().y(q[1]);
 267         nodes->back().h(q[2]);
 268         nodes->back().sp(q[3]);
 269         if (nodes->back().sp() == 0) {
 270                 nodes->back().set_t(RRTNodeType::cusp);
 271         } else if (nodes->size() >= 2) {
 272                 RRTNode* lln = nodes->back().p();
 273                 RRTNode* ln = &nodes->back();
 274                 if (lln != nullptr && ln != nullptr && sgn(lln->sp()) != sgn(ln->sp()))
 275                         ln->set_t(RRTNodeType::cusp);
 276         }
 277         return 0;
 278 }
 279
 280 void RRTS::steer(RRTNode &f, RRTNode &t)
 281 {
 282         this->steered().clear();
 283         double q0[] = {f.x(), f.y(), f.h()};
 284         double q1[] = {t.x(), t.y(), t.h()};
 285         ReedsSheppStateSpace rsss(this->bc.mtr());
 286         rsss.sample(q0, q1, 0.05, cb_rs_steer, &this->steered());
 287 }
 288
 289 void RRTS::steer1(RRTNode &f, RRTNode &t)
 290 {
 291     return this->steer(f, t);
 292 }
 293
 294 void RRTS::steer2(RRTNode &f, RRTNode &t)
 295 {
 296     return this->steer(f, t);
 297 }
 298
 299 void RRTS::join_steered(RRTNode *f)
 300 {
 301         while (this->steered().size() > 0) {
 302                 this->store_node(this->steered().front());
 303                 RRTNode *t = &this->nodes().back();
 304                 t->p(f);
 305                 t->c(this->cost_build(*f, *t));
 306                 this->steered().erase(this->steered().begin());
 307                 f = t;
 308         }
 309 }
 310
 311 bool RRTS::goal_found(RRTNode &f)
 312 {
 313         auto &g = this->goals().front();
 314         double cost = this->cost_build(f, g);
 315         double edist = sqrt(
 316                 pow(f.x() - g.x(), 2)
 317                 + pow(f.y() - g.y(), 2)
 318         );
 319         double adist = std::abs(f.h() - g.h());
 320         if (edist < 0.05 && adist < M_PI / 32) {
 321                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 322                         g.p(&f);
 323                         g.c(cost);
 324                 }
 325                 return true;
 326         }
 327         return false;
 328 }
 329
 330 // RRT* procedures
 331 bool RRTS::connect()
 332 {
 333         RRTNode *t = &this->steered().front();
 334         RRTNode *f = this->nn(this->samples().back());
 335         double cost = this->cost_search(*f, *t);
 336         for (auto n: this->nv(*t)) {
 337                 if (
 338                         !std::get<0>(this->collide_two_nodes(*n, *t))
 339                         && this->cost_search(*n, *t) < cost
 340                 ) {
 341                         f = n;
 342                         cost = this->cost_search(*n, *t);
 343                 }
 344         }
 345         this->store_node(this->steered().front());
 346         t = &this->nodes().back();
 347         t->p(f);
 348         t->c(this->cost_build(*f, *t));
 349         t->set_t(RRTNodeType::connected);
 350         return true;
 351 }
 352
 353 void RRTS::rewire()
 354 {
 355         RRTNode *f = &this->nodes().back();
 356         for (auto n: this->nv(*f)) {
 357                 if (
 358                         !std::get<0>(this->collide_two_nodes(*f, *n))
 359                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 360                 ) {
 361                         n->p(f);
 362                         n->c(this->cost_build(*f, *n));
 363                 }
 364         }
 365 }
 366
 367 // API
 368 void RRTS::init()
 369 {
 370 }
 371
 372 void RRTS::deinit()
 373 {
 374         this->nodes().clear();
 375         this->samples().clear();
 376         this->steered().clear();
 377         this->store_node(RRTNode()); // root
 378         this->icnt_ = 0;
 379         this->scnt_ = 0;
 380         this->pcnt_ = 0;
 381         this->gf_ = false;
 382 }
 383
 384 std::vector<RRTNode *> RRTS::path()
 385 {
 386         std::vector<RRTNode *> path;
 387         if (this->goals().size() == 0)
 388                 return path;
 389         RRTNode *goal = &this->goals().back();
 390         if (goal->p() == nullptr)
 391                 return path;
 392         while (goal != nullptr) {
 393                 path.push_back(goal);
 394                 goal = goal->p();
 395         }
 396         std::reverse(path.begin(), path.end());
 397         return path;
 398 }
 399
 400 bool RRTS::next()
 401 {
 402         if (this->icnt_ == 0)
 403                 this->tstart_ = std::chrono::high_resolution_clock::now();
 404         bool next = true;
 405         if (this->scnt_ > this->log_path_time_)
 406             this->log_path_cost();
 407         if (this->should_stop())
 408                 return false;
 409         if (this->samples().size() == 0) {
 410                 this->samples().push_back(RRTNode());
 411                 this->samples().back().x(this->goals().front().x());
 412                 this->samples().back().y(this->goals().front().y());
 413                 this->samples().back().h(this->goals().front().h());
 414         } else {
 415                 this->sample();
 416         }
 417         this->steer1(
 418                 *this->nn(this->samples().back()),
 419                 this->samples().back()
 420         );
 421         if (this->steered().size() == 0)
 422                 return next;
 423         auto col = this->collide_steered_from(
 424                 *this->nn(this->samples().back())
 425         );
 426         if (std::get<0>(col)) {
 427                 auto rcnt = this->steered().size() - std::get<1>(col);
 428                 while (rcnt-- > 0) {
 429                         this->steered().pop_back();
 430                 }
 431         }
 432         if (!this->connect())
 433                 return next;
 434         this->rewire();
 435         unsigned scnt = this->steered().size();
 436         this->join_steered(&this->nodes().back());
 437         RRTNode *just_added = &this->nodes().back();
 438         while (scnt > 0) {
 439                 scnt--;
 440                 auto &g = this->goals().front();
 441                 this->steer2(*just_added, g);
 442                 if (std::get<0>(this->collide_steered_from(
 443                         *just_added
 444                 )))
 445                         continue;
 446                 this->join_steered(just_added);
 447                 this->gf(this->goal_found(this->nodes().back()));
 448                 just_added = just_added->p();
 449         }
 450         return next;
 451 }
 452
 453 void RRTS::set_sample_normal(
 454         double mx, double dx,
 455         double my, double dy,
 456         double mh, double dh
 457 )
 458 {
 459         this->ndx_ = std::normal_distribution<double>(mx, dx);
 460         this->ndy_ = std::normal_distribution<double>(my, dy);
 461         this->ndh_ = std::normal_distribution<double>(mh, dh);
 462 }
 463 void RRTS::set_sample_uniform(
 464         double xmin, double xmax,
 465         double ymin, double ymax,
 466         double hmin, double hmax
 467 )
 468 {
 469         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 470         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 471         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 472 }
 473 void RRTS::set_sample_uniform_circle()
 474 {
 475         this->udx_ = std::uniform_real_distribution<double>(0, 1);
 476         this->udy_ = std::uniform_real_distribution<double>(0, 1);
 477         this->udh_ = std::uniform_real_distribution<double>(0, 2 * M_PI);
 478 }
 479 void RRTS::set_sample(
 480         double x1, double x2,
 481         double y1, double y2,
 482         double h1, double h2
 483 )
 484 {
 485         switch (this->sample_dist_type()) {
 486         case 1: // uniform
 487                 x1 += this->nodes().front().x();
 488                 x2 += this->nodes().front().x();
 489                 y1 += this->nodes().front().y();
 490                 y2 += this->nodes().front().y();
 491                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 492                 break;
 493         case 2: // uniform circle
 494                 this->set_sample_uniform_circle();
 495                 break;
 496         case 3: // uniform index of node in nodes
 497                 this->set_sample_uniform_circle();
 498                 break;
 499         default: // normal
 500                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 501         }
 502 }
 503
 504 Json::Value RRTS::json()
 505 {
 506         Json::Value jvo;
 507         {
 508                 jvo["time"] = this->scnt();
 509         }
 510         {
 511                 jvo["iterations"] = this->icnt();
 512         }
 513         {
 514                 jvo["init"][0] = this->nodes().front().x();
 515                 jvo["init"][1] = this->nodes().front().y();
 516                 jvo["init"][2] = this->nodes().front().h();
 517         }
 518         {
 519                 jvo["path_cost_before_opt"] = this->path_cost_before_opt_;
 520         }
 521         {
 522                 if (this->path().size() > 0) {
 523                         jvo["cost"] = cc(*this->path().back());
 524                         jvo["entry"][0] = this->goals().front().x();
 525                         jvo["entry"][1] = this->goals().front().y();
 526                         jvo["entry"][2] = this->goals().front().h();
 527                         jvo["goal"][0] = this->goals().back().x();
 528                         jvo["goal"][1] = this->goals().back().y();
 529                         jvo["goal"][2] = this->goals().back().h();
 530                 }
 531         }
 532         {
 533                 unsigned int cu = 0;
 534                 unsigned int co = 0;
 535                 unsigned int pcnt = 0;
 536                 for (auto n: this->path()) {
 537                         jvo["path"][pcnt][0] = n->x();
 538                         jvo["path"][pcnt][1] = n->y();
 539                         jvo["path"][pcnt][2] = n->h();
 540                         if (n->t(RRTNodeType::cusp))
 541                                 cu++;
 542                         if (n->t(RRTNodeType::connected))
 543                                 co++;
 544                         pcnt++;
 545                 }
 546                 jvo["cusps-in-path"] = cu;
 547                 jvo["connecteds-in-path"] = co;
 548         }
 549         {
 550                 unsigned int gcnt = 0;
 551                 for (auto g: this->goals()) {
 552                         jvo["goals"][gcnt][0] = g.x();
 553                         jvo["goals"][gcnt][1] = g.y();
 554                         jvo["goals"][gcnt][2] = g.h();
 555                         gcnt++;
 556                 }
 557         }
 558         {
 559                 unsigned int ocnt = 0;
 560                 for (auto o: this->obstacles()) {
 561                         unsigned int ccnt = 0;
 562                         for (auto c: o.poly()) {
 563                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 564                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 565                                 ccnt++;
 566                         }
 567                         ocnt++;
 568                 }
 569         }
 570         {
 571                 jvo["nodes"] = (unsigned int) this->nodes().size();
 572         }
 573         {
 574                 unsigned int cnt = 0;
 575                 for (auto i: this->log_path_cost_)
 576                         jvo["log_path_cost"][cnt++] = i;
 577         }
 578         //{
 579         //        unsigned int ncnt = 0;
 580         //        for (auto n: this->nodes()) {
 581         //                jvo["nodes_x"][ncnt] = n.x();
 582         //                jvo["nodes_y"][ncnt] = n.y();
 583         //                //jvo["nodes_h"][ncnt] = n.h();
 584         //                ncnt++;
 585         //        }
 586         //}
 587         return jvo;
 588 }
 589
 590 void RRTS::json(Json::Value jvi)
 591 {
 592         assert(jvi["init"] != Json::nullValue);
 593         assert(jvi["goals"] != Json::nullValue);
 594         assert(jvi["obst"] != Json::nullValue);
 595
 596         this->nodes().front().x(jvi["init"][0].asDouble());
 597         this->nodes().front().y(jvi["init"][1].asDouble());
 598         this->nodes().front().h(jvi["init"][2].asDouble());
 599         {
 600                 RRTNode* gp = nullptr;
 601                 if (jvi["entry"] != Json::nullValue) {
 602                         this->entry_set = true;
 603                         this->entry.x = jvi["entry"][0].asDouble();
 604                         this->entry.y = jvi["entry"][1].asDouble();
 605                         this->entry.b = jvi["entry"][2].asDouble();
 606                         this->entry.e = jvi["entry"][3].asDouble();
 607                         RRTNode tmp_node;
 608                         tmp_node.x(this->entry.x);
 609                         tmp_node.y(this->entry.y);
 610                         tmp_node.h((this->entry.b + this->entry.e) / 2.0);
 611                         this->goals().push_back(tmp_node);
 612                         this->goals().back().p(gp);
 613                         gp = &this->goals().back();
 614                 }
 615                 for (auto g: jvi["goals"]) {
 616                         RRTNode tmp_node;
 617                         tmp_node.x(g[0].asDouble());
 618                         tmp_node.y(g[1].asDouble());
 619                         tmp_node.h(g[2].asDouble());
 620                         this->goals().push_back(tmp_node);
 621                         this->goals().back().p(gp);
 622                         gp = &this->goals().back();
 623                 }
 624                 this->goals().front().set_t(RRTNodeType::cusp);
 625                 this->goals().back().set_t(RRTNodeType::cusp);
 626         }
 627         {
 628                 Obstacle tmp_obstacle;
 629                 for (auto o: jvi["obst"]) {
 630                         tmp_obstacle.poly().clear();
 631                         for (auto c: o) {
 632                                 double tmp_x = c[0].asDouble();
 633                                 double tmp_y = c[1].asDouble();
 634                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 635                                 tmp_obstacle.poly().push_back(tmp_tuple);
 636                         }
 637                         this->obstacles().push_back(tmp_obstacle);
 638                 }
 639         }
 640         {
 641                 double edist_init_goal = sqrt(
 642                         pow(
 643                                 this->nodes().front().x()
 644                                 - this->goals().front().x(),
 645                                 2
 646                         )
 647                         + pow(
 648                                 this->nodes().front().y()
 649                                 - this->goals().front().y(),
 650                                 2
 651                         )
 652                 );
 653                 this->set_sample(
 654                         this->nodes().front().x(), edist_init_goal,
 655                         this->nodes().front().y(), edist_init_goal,
 656                         0, 2 * M_PI
 657                 );
 658         }
 659 }
 660
 661 RRTS::RRTS()
 662         : gen_(std::random_device{}())
 663 {
 664         this->goals().reserve(100);
 665         this->nodes().reserve(4000000);
 666         this->samples().reserve(1000);
 667         this->steered().reserve(20000);
 668         this->store_node(RRTNode()); // root
 669 }
 670
 671 double cc(RRTNode &t)
 672 {
 673         RRTNode *n = &t;
 674         double cost = 0;
 675         while (n != nullptr) {
 676                 cost += n->c();
 677                 n = n->p();
 678         }
 679         return cost;
 680 }