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 bool RRTS::should_stop()
  46 {
  47         // the following counters must be updated, do not comment
  48         this->icnt_++;
  49         this->elapsed();
  50         // current iteration stop conditions
  51         if (this->should_finish()) return true;
  52         if (this->should_break()) return true;
  53         // but continue by default
  54         return false;
  55 }
  56
  57 bool RRTS::should_finish()
  58 {
  59         // decide finish conditions (maybe comment some lines)
  60         //if (this->icnt_ > 999) return true;
  61         if (this->scnt_ > 10) return true;
  62         if (this->gf()) return true;
  63         // but continue by default
  64         return false;
  65 }
  66
  67 bool RRTS::should_break()
  68 {
  69         // decide break conditions (maybe comment some lines)
  70         //if (this->scnt_ - this->pcnt_ > 2) return true;
  71         // but continue by default
  72         return false;
  73 }
  74
  75 bool RRTS::should_continue()
  76 {
  77         // decide the stop conditions (maybe comment some lines)
  78         // it is exact opposite of `should_stop`
  79         //if (this->icnt_ > 999) return false;
  80         if (this->scnt_ > 10) return false;
  81         if (this->gf()) return false;
  82         // and reset pause counter if should continue
  83         this->pcnt_ = this->scnt_;
  84         return true;
  85 }
  86
  87 void RRTS::store_node(RRTNode n)
  88 {
  89         this->nodes().push_back(n);
  90 }
  91
  92 // RRT procedures
  93 std::tuple<bool, unsigned int, unsigned int>
  94 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
  95 {
  96         for (auto &o: this->obstacles())
  97                 if (std::get<0>(::collide(poly, o.poly())))
  98                         return ::collide(poly, o.poly());
  99         return std::make_tuple(false, 0, 0);
 100 }
 101
 102 std::tuple<bool, unsigned int, unsigned int>
 103 RRTS::collide_steered_from(RRTNode &f)
 104 {
 105         auto fbc = BicycleCar();
 106         fbc.x(f.x());
 107         fbc.y(f.y());
 108         fbc.h(f.h());
 109         std::vector<std::tuple<double, double>> s;
 110         s.push_back(std::make_tuple(fbc.x(), fbc.y()));
 111         for (auto &n: this->steered()) {
 112                 auto nbc = BicycleCar();
 113                 nbc.x(n.x());
 114                 nbc.y(n.y());
 115                 nbc.h(n.h());
 116                 s.push_back(std::make_tuple(nbc.lfx(), nbc.lfy()));
 117                 s.push_back(std::make_tuple(nbc.lrx(), nbc.lry()));
 118                 s.push_back(std::make_tuple(nbc.rrx(), nbc.rry()));
 119                 s.push_back(std::make_tuple(nbc.rfx(), nbc.rfy()));
 120         }
 121         auto col = this->collide(s);
 122         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 123         if (std::get<0>(col) && strip_from > 0) {
 124                 while (strip_from-- > 0) {
 125                         this->steered().pop_back();
 126                 }
 127                 return this->collide_steered_from(f);
 128         }
 129         return col;
 130 }
 131
 132 std::tuple<bool, unsigned int, unsigned int>
 133 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 134 {
 135         auto fbc = BicycleCar();
 136         fbc.x(f.x());
 137         fbc.y(f.y());
 138         fbc.h(f.h());
 139         auto tbc = BicycleCar();
 140         tbc.x(f.x());
 141         tbc.y(f.y());
 142         tbc.h(f.h());
 143         std::vector<std::tuple<double, double>> p;
 144         p.push_back(std::make_tuple(fbc.lfx(), fbc.lfy()));
 145         p.push_back(std::make_tuple(fbc.lrx(), fbc.lry()));
 146         p.push_back(std::make_tuple(fbc.rrx(), fbc.rry()));
 147         p.push_back(std::make_tuple(fbc.rfx(), fbc.rfy()));
 148         p.push_back(std::make_tuple(tbc.lfx(), tbc.lfy()));
 149         p.push_back(std::make_tuple(tbc.lrx(), tbc.lry()));
 150         p.push_back(std::make_tuple(tbc.rrx(), tbc.rry()));
 151         p.push_back(std::make_tuple(tbc.rfx(), tbc.rfy()));
 152         return this->collide(p);
 153 }
 154
 155 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 156 {
 157         double cost = 0;
 158         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 159         return cost;
 160 }
 161
 162 double RRTS::cost_search(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 void RRTS::sample()
 170 {
 171         double x = 0;
 172         double y = 0;
 173         double h = 0;
 174         switch (this->sample_dist_type()) {
 175         case 1: // uniform
 176                 x = this->udx_(this->gen_);
 177                 y = this->udy_(this->gen_);
 178                 h = this->udh_(this->gen_);
 179                 break;
 180         case 2: // uniform circle
 181         {
 182                 // see https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly/50746409#50746409
 183                 double R = sqrt(
 184                         pow(
 185                                 this->nodes().front().x()
 186                                 - this->goals().front().x(),
 187                                 2
 188                         )
 189                         + pow(
 190                                 this->nodes().front().y()
 191                                 - this->goals().front().y(),
 192                                 2
 193                         )
 194                 );
 195                 double a = atan2(
 196                         this->goals().front().y() - this->nodes().front().y(),
 197                         this->goals().front().x() - this->nodes().front().x()
 198                 );
 199                 double cx = this->goals().front().x() + R/2 * cos(a);
 200                 double cy = this->goals().front().y() + R/2 * sin(a);
 201                 double r = R * sqrt(this->udx_(this->gen_));
 202                 double theta = this->udy_(this->gen_) * 2 * M_PI;
 203                 x = cx + r * cos(theta);
 204                 y = cy + r * sin(theta);
 205                 h = this->udh_(this->gen_);
 206         }
 207                 break;
 208         default: // normal
 209                 x = this->ndx_(this->gen_);
 210                 y = this->ndy_(this->gen_);
 211                 h = this->ndh_(this->gen_);
 212         }
 213         this->samples().push_back(RRTNode());
 214         this->samples().back().x(x);
 215         this->samples().back().y(y);
 216         this->samples().back().h(h);
 217 }
 218
 219 RRTNode *RRTS::nn(RRTNode &t)
 220 {
 221         RRTNode *nn = &this->nodes().front();
 222         double cost = this->cost_search(*nn, t);
 223         for (auto &f: this->nodes()) {
 224                 if (this->cost_search(f, t) < cost) {
 225                         nn = &f;
 226                         cost = this->cost_search(f, t);
 227                 }
 228         }
 229         return nn;
 230 }
 231
 232 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 233 {
 234         std::vector<RRTNode *> nv;
 235         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 236         for (auto &f: this->nodes())
 237                 if (this->cost_search(f, t) < cost)
 238                         nv.push_back(&f);
 239         return nv;
 240 }
 241
 242 int cb_rs_steer(double q[4], void *user_data)
 243 {
 244         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 245         RRTNode *ln = nullptr;
 246         if (nodes->size() > 0)
 247                 ln = &nodes->back();
 248         nodes->push_back(RRTNode());
 249         nodes->back().x(q[0]);
 250         nodes->back().y(q[1]);
 251         nodes->back().h(q[2]);
 252         nodes->back().sp(q[3]);
 253         if (nodes->back().sp() == 0)
 254                 nodes->back().set_t(RRTNodeType::cusp);
 255         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 256                 ln->set_t(RRTNodeType::cusp);
 257         return 0;
 258 }
 259
 260 void RRTS::steer(RRTNode &f, RRTNode &t)
 261 {
 262         this->steered().clear();
 263         double q0[] = {f.x(), f.y(), f.h()};
 264         double q1[] = {t.x(), t.y(), t.h()};
 265         ReedsSheppStateSpace rsss(this->bc.mtr());
 266         rsss.sample(q0, q1, 0.5, cb_rs_steer, &this->steered());
 267 }
 268
 269 void RRTS::join_steered(RRTNode *f)
 270 {
 271         while (this->steered().size() > 0) {
 272                 this->store_node(this->steered().front());
 273                 RRTNode *t = &this->nodes().back();
 274                 t->p(f);
 275                 t->c(this->cost_build(*f, *t));
 276                 this->steered().erase(this->steered().begin());
 277                 f = t;
 278         }
 279 }
 280
 281 bool RRTS::goal_found(RRTNode &f)
 282 {
 283         auto &g = this->goals().front();
 284         double cost = this->cost_build(f, g);
 285         double edist = sqrt(
 286                 pow(f.x() - g.x(), 2)
 287                 + pow(f.y() - g.y(), 2)
 288         );
 289         double adist = std::abs(f.h() - g.h());
 290         if (edist < 0.05 && adist < M_PI / 32) {
 291                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 292                         g.p(&f);
 293                         g.c(cost);
 294                 }
 295                 return true;
 296         }
 297         return false;
 298 }
 299
 300 // RRT* procedures
 301 bool RRTS::connect()
 302 {
 303         RRTNode *t = &this->steered().front();
 304         RRTNode *f = this->nn(this->samples().back());
 305         double cost = this->cost_search(*f, *t);
 306         for (auto n: this->nv(*t)) {
 307                 if (
 308                         !std::get<0>(this->collide_two_nodes(*n, *t))
 309                         && this->cost_search(*n, *t) < cost
 310                 ) {
 311                         f = n;
 312                         cost = this->cost_search(*n, *t);
 313                 }
 314         }
 315         this->store_node(this->steered().front());
 316         t = &this->nodes().back();
 317         t->p(f);
 318         t->c(this->cost_build(*f, *t));
 319         t->set_t(RRTNodeType::connected);
 320         return true;
 321 }
 322
 323 void RRTS::rewire()
 324 {
 325         RRTNode *f = &this->nodes().back();
 326         for (auto n: this->nv(*f)) {
 327                 if (
 328                         !std::get<0>(this->collide_two_nodes(*f, *n))
 329                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 330                 ) {
 331                         n->p(f);
 332                         n->c(this->cost_build(*f, *n));
 333                 }
 334         }
 335 }
 336
 337 // API
 338 void RRTS::init()
 339 {
 340 }
 341
 342 void RRTS::deinit()
 343 {
 344         this->nodes().clear();
 345         this->samples().clear();
 346         this->steered().clear();
 347         this->store_node(RRTNode()); // root
 348         this->icnt_ = 0;
 349         this->scnt_ = 0;
 350         this->pcnt_ = 0;
 351         this->gf_ = false;
 352 }
 353
 354 std::vector<RRTNode *> RRTS::path()
 355 {
 356         std::vector<RRTNode *> path;
 357         if (this->goals().size() == 0)
 358                 return path;
 359         RRTNode *goal = &this->goals().front();
 360         if (goal->p() == nullptr)
 361                 return path;
 362         while (goal != nullptr) {
 363                 path.push_back(goal);
 364                 goal = goal->p();
 365         }
 366         std::reverse(path.begin(), path.end());
 367         return path;
 368 }
 369
 370 bool RRTS::next()
 371 {
 372         if (this->icnt_ == 0)
 373                 this->tstart_ = std::chrono::high_resolution_clock::now();
 374         bool next = true;
 375         if (this->should_stop())
 376                 return false;
 377         if (this->samples().size() == 0) {
 378                 this->samples().push_back(RRTNode());
 379                 this->samples().back().x(this->goals().front().x());
 380                 this->samples().back().y(this->goals().front().y());
 381                 this->samples().back().h(this->goals().front().h());
 382         } else {
 383                 this->sample();
 384         }
 385         this->steer(
 386                 *this->nn(this->samples().back()),
 387                 this->samples().back()
 388         );
 389         if (std::get<0>(this->collide_steered_from(
 390                 *this->nn(this->samples().back())
 391         )))
 392                 return next;
 393         if (!this->connect())
 394                 return next;
 395         this->rewire();
 396         unsigned scnt = this->steered().size();
 397         this->join_steered(&this->nodes().back());
 398         RRTNode *just_added = &this->nodes().back();
 399         while (scnt > 0) {
 400                 scnt--;
 401                 auto &g = this->goals().front();
 402                 this->steer(*just_added, g);
 403                 if (std::get<0>(this->collide_steered_from(
 404                         *just_added
 405                 )))
 406                         continue;
 407                 this->join_steered(just_added);
 408                 this->gf(this->goal_found(this->nodes().back()));
 409                 just_added = just_added->p();
 410         }
 411         return next;
 412 }
 413
 414 void RRTS::set_sample_normal(
 415         double mx, double dx,
 416         double my, double dy,
 417         double mh, double dh
 418 )
 419 {
 420         this->ndx_ = std::normal_distribution<double>(mx, dx);
 421         this->ndy_ = std::normal_distribution<double>(my, dy);
 422         this->ndh_ = std::normal_distribution<double>(mh, dh);
 423 }
 424 void RRTS::set_sample_uniform(
 425         double xmin, double xmax,
 426         double ymin, double ymax,
 427         double hmin, double hmax
 428 )
 429 {
 430         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 431         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 432         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 433 }
 434 void RRTS::set_sample_uniform_circle()
 435 {
 436         this->udx_ = std::uniform_real_distribution<double>(0, 1);
 437         this->udy_ = std::uniform_real_distribution<double>(0, 1);
 438         this->udh_ = std::uniform_real_distribution<double>(0, 2 * M_PI);
 439 }
 440 void RRTS::set_sample(
 441         double x1, double x2,
 442         double y1, double y2,
 443         double h1, double h2
 444 )
 445 {
 446         switch (this->sample_dist_type()) {
 447         case 1: // uniform
 448                 x1 += this->nodes().front().x();
 449                 x2 += this->nodes().front().x();
 450                 y1 += this->nodes().front().y();
 451                 y2 += this->nodes().front().y();
 452                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 453                 break;
 454         case 2: // uniform circle
 455                 this->set_sample_uniform_circle();
 456                 break;
 457         default: // normal
 458                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 459         }
 460 }
 461
 462 Json::Value RRTS::json()
 463 {
 464         Json::Value jvo;
 465         {
 466                 jvo["time"] = this->scnt();
 467         }
 468         {
 469                 jvo["iterations"] = this->icnt();
 470         }
 471         {
 472                 jvo["init"][0] = this->nodes().front().x();
 473                 jvo["init"][1] = this->nodes().front().y();
 474                 jvo["init"][2] = this->nodes().front().h();
 475         }
 476         {
 477                 if (this->path().size() > 0) {
 478                         jvo["cost"] = cc(*this->path().back());
 479                         jvo["goal"][0] = this->path().back()->x();
 480                         jvo["goal"][1] = this->path().back()->y();
 481                         jvo["goal"][2] = this->path().back()->h();
 482                 }
 483         }
 484         {
 485                 unsigned int cu = 0;
 486                 unsigned int co = 0;
 487                 unsigned int pcnt = 0;
 488                 for (auto n: this->path()) {
 489                         jvo["path"][pcnt][0] = n->x();
 490                         jvo["path"][pcnt][1] = n->y();
 491                         jvo["path"][pcnt][2] = n->h();
 492                         if (n->t(RRTNodeType::cusp))
 493                                 cu++;
 494                         if (n->t(RRTNodeType::connected))
 495                                 co++;
 496                         pcnt++;
 497                 }
 498                 jvo["cusps-in-path"] = cu;
 499                 jvo["connecteds-in-path"] = co;
 500         }
 501         {
 502                 unsigned int gcnt = 0;
 503                 for (auto g: this->goals()) {
 504                         jvo["goals"][gcnt][0] = g.x();
 505                         jvo["goals"][gcnt][1] = g.y();
 506                         jvo["goals"][gcnt][2] = g.h();
 507                         gcnt++;
 508                 }
 509         }
 510         {
 511                 unsigned int ocnt = 0;
 512                 for (auto o: this->obstacles()) {
 513                         unsigned int ccnt = 0;
 514                         for (auto c: o.poly()) {
 515                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 516                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 517                                 ccnt++;
 518                         }
 519                         ocnt++;
 520                 }
 521         }
 522         {
 523                 jvo["nodes"] = (unsigned int) this->nodes().size();
 524         }
 525         //{
 526         //        unsigned int ncnt = 0;
 527         //        for (auto n: this->nodes()) {
 528         //                jvo["nodes_x"][ncnt] = n.x();
 529         //                jvo["nodes_y"][ncnt] = n.y();
 530         //                //jvo["nodes_h"][ncnt] = n.h();
 531         //                ncnt++;
 532         //        }
 533         //}
 534         return jvo;
 535 }
 536
 537 void RRTS::json(Json::Value jvi)
 538 {
 539         assert(jvi["init"] != Json::nullValue);
 540         assert(jvi["goal"] != Json::nullValue);
 541         assert(jvi["goals"] != Json::nullValue);
 542         assert(jvi["obst"] != Json::nullValue);
 543
 544         this->nodes().front().x(jvi["init"][0].asDouble());
 545         this->nodes().front().y(jvi["init"][1].asDouble());
 546         this->nodes().front().h(jvi["init"][2].asDouble());
 547         {
 548                 RRTNode tmp_node;
 549                 tmp_node.x(jvi["goal"][0].asDouble());
 550                 tmp_node.y(jvi["goal"][1].asDouble());
 551                 tmp_node.h(jvi["goal"][2].asDouble());
 552                 this->goals().push_back(tmp_node);
 553                 for (auto g: jvi["goals"]) {
 554                         tmp_node.x(g[0].asDouble());
 555                         tmp_node.y(g[1].asDouble());
 556                         tmp_node.h(g[2].asDouble());
 557                         this->goals().push_back(tmp_node);
 558                 }
 559         }
 560         {
 561                 Obstacle tmp_obstacle;
 562                 for (auto o: jvi["obst"]) {
 563                         tmp_obstacle.poly().clear();
 564                         for (auto c: o) {
 565                                 double tmp_x = c[0].asDouble();
 566                                 double tmp_y = c[1].asDouble();
 567                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 568                                 tmp_obstacle.poly().push_back(tmp_tuple);
 569                         }
 570                         this->obstacles().push_back(tmp_obstacle);
 571                 }
 572         }
 573         {
 574                 double edist_init_goal = sqrt(
 575                         pow(
 576                                 this->nodes().front().x()
 577                                 - this->goals().front().x(),
 578                                 2
 579                         )
 580                         + pow(
 581                                 this->nodes().front().y()
 582                                 - this->goals().front().y(),
 583                                 2
 584                         )
 585                 );
 586                 this->set_sample(
 587                         this->nodes().front().x(), edist_init_goal,
 588                         this->nodes().front().y(), edist_init_goal,
 589                         0, 2 * M_PI
 590                 );
 591         }
 592 }
 593
 594 RRTS::RRTS()
 595         : gen_(std::random_device{}())
 596 {
 597         this->goals().reserve(100);
 598         this->nodes().reserve(4000000);
 599         this->samples().reserve(1000);
 600         this->steered().reserve(20000);
 601         this->store_node(RRTNode()); // root
 602 }
 603
 604 double cc(RRTNode &t)
 605 {
 606         RRTNode *n = &t;
 607         double cost = 0;
 608         while (n != nullptr) {
 609                 cost += n->c();
 610                 n = n->p();
 611         }
 612         return cost;
 613 }