src/rrts.cc

   1 #include <algorithm>
   2 #include "rrts.h"
   3
   4 #include "reeds_shepp.h"
   5 #include <iostream>
   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) : BicycleCar(bc)
  15 {
  16 }
  17
  18 Obstacle::Obstacle()
  19 {
  20 }
  21
  22 double RRTS::elapsed()
  23 {
  24         std::chrono::duration<double> dt;
  25         dt = std::chrono::duration_cast<std::chrono::duration<double>>(
  26                 std::chrono::high_resolution_clock::now()
  27                 - this->tstart_
  28         );
  29         this->scnt_ = dt.count();
  30         return this->scnt_;
  31 }
  32
  33 bool RRTS::should_stop()
  34 {
  35         // the following counters must be updated, do not comment
  36         this->icnt_++;
  37         this->elapsed();
  38         // current iteration stop conditions
  39         if (this->should_finish()) return true;
  40         if (this->should_break()) return true;
  41         // but continue by default
  42         return false;
  43 }
  44
  45 bool RRTS::should_finish()
  46 {
  47         // decide finish conditions (maybe comment some lines)
  48         //if (this->icnt_ > 999) return true;
  49         if (this->scnt_ > 50) return true;
  50         if (this->gf()) return true;
  51         // but continue by default
  52         return false;
  53 }
  54
  55 bool RRTS::should_break()
  56 {
  57         // decide break conditions (maybe comment some lines)
  58         //if (this->scnt_ - this->pcnt_ > 2) return true;
  59         // but continue by default
  60         return false;
  61 }
  62
  63 bool RRTS::should_continue()
  64 {
  65         // decide the stop conditions (maybe comment some lines)
  66         // it is exact opposite of `should_stop`
  67         //if (this->icnt_ > 999) return false;
  68         if (this->scnt_ > 10) return false;
  69         if (this->gf()) return false;
  70         // and reset pause counter if should continue
  71         this->pcnt_ = this->scnt_;
  72         return true;
  73 }
  74
  75 void RRTS::store_node(RRTNode n)
  76 {
  77         this->nodes().push_back(n);
  78 }
  79
  80 // RRT procedures
  81 std::tuple<bool, unsigned int, unsigned int>
  82 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
  83 {
  84         for (auto &o: this->obstacles())
  85                 if (std::get<0>(::collide(poly, o.poly())))
  86                         return ::collide(poly, o.poly());
  87         return std::make_tuple(false, 0, 0);
  88 }
  89
  90 std::tuple<bool, unsigned int, unsigned int>
  91 RRTS::collide_steered_from(RRTNode &f)
  92 {
  93         std::vector<std::tuple<double, double>> s;
  94         s.push_back(std::make_tuple(f.x(), f.y()));
  95         for (auto &n: this->steered()) {
  96                 s.push_back(std::make_tuple(n.lfx(), n.lfy()));
  97                 s.push_back(std::make_tuple(n.lrx(), n.lry()));
  98                 s.push_back(std::make_tuple(n.rrx(), n.rry()));
  99                 s.push_back(std::make_tuple(n.rfx(), n.rfy()));
 100         }
 101         auto col = this->collide(s);
 102         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 103         if (std::get<0>(col) && strip_from > 0) {
 104                 while (strip_from-- > 0) {
 105                         this->steered().pop_back();
 106                 }
 107                 return this->collide_steered_from(f);
 108         }
 109         return col;
 110 }
 111
 112 std::tuple<bool, unsigned int, unsigned int>
 113 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 114 {
 115         std::vector<std::tuple<double, double>> p;
 116         p.push_back(std::make_tuple(f.lfx(), f.lfy()));
 117         p.push_back(std::make_tuple(f.lrx(), f.lry()));
 118         p.push_back(std::make_tuple(f.rrx(), f.rry()));
 119         p.push_back(std::make_tuple(f.rfx(), f.rfy()));
 120         p.push_back(std::make_tuple(t.lfx(), t.lfy()));
 121         p.push_back(std::make_tuple(t.lrx(), t.lry()));
 122         p.push_back(std::make_tuple(t.rrx(), t.rry()));
 123         p.push_back(std::make_tuple(t.rfx(), t.rfy()));
 124         return this->collide(p);
 125 }
 126
 127 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 128 {
 129         double cost = 0;
 130         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 131         return cost;
 132 }
 133
 134 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 135 {
 136         double cost = 0;
 137         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 138         return cost;
 139 }
 140
 141 void RRTS::sample()
 142 {
 143         double x = 0;
 144         double y = 0;
 145         double h = 0;
 146         switch (this->sample_dist_type()) {
 147         case 1:
 148                 x = this->udx_(this->gen_);
 149                 y = this->udy_(this->gen_);
 150                 h = this->udh_(this->gen_);
 151                 break;
 152         default:
 153                 x = this->ndx_(this->gen_);
 154                 y = this->ndy_(this->gen_);
 155                 h = this->ndh_(this->gen_);
 156         }
 157         this->samples().push_back(RRTNode());
 158         this->samples().back().x(x);
 159         this->samples().back().y(y);
 160         this->samples().back().h(h);
 161 }
 162
 163 RRTNode *RRTS::nn(RRTNode &t)
 164 {
 165         RRTNode *nn = &this->nodes().front();
 166         double cost = this->cost_search(*nn, t);
 167         for (auto &f: this->nodes()) {
 168                 if (this->cost_search(f, t) < cost) {
 169                         nn = &f;
 170                         cost = this->cost_search(f, t);
 171                 }
 172         }
 173         return nn;
 174 }
 175
 176 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 177 {
 178         std::vector<RRTNode *> nv;
 179         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 180         for (auto &f: this->nodes())
 181                 if (this->cost_search(f, t) < cost)
 182                         nv.push_back(&f);
 183         return nv;
 184 }
 185
 186 int cb_rs_steer(double q[4], void *user_data)
 187 {
 188         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 189         RRTNode *ln = nullptr;
 190         if (nodes->size() > 0)
 191                 ln = &nodes->back();
 192         nodes->push_back(RRTNode());
 193         nodes->back().x(q[0]);
 194         nodes->back().y(q[1]);
 195         nodes->back().h(q[2]);
 196         nodes->back().sp(q[3]);
 197         if (nodes->back().sp() == 0)
 198                 nodes->back().set_t(RRTNodeType::cusp);
 199         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 200                 ln->set_t(RRTNodeType::cusp);
 201         return 0;
 202 }
 203
 204 void RRTS::steer(RRTNode &f, RRTNode &t)
 205 {
 206         this->steered().clear();
 207         double q0[] = {f.x(), f.y(), f.h()};
 208         double q1[] = {t.x(), t.y(), t.h()};
 209         ReedsSheppStateSpace rsss(f.mtr());
 210         rsss.sample(q0, q1, 0.5, cb_rs_steer, &this->steered());
 211 }
 212
 213 void RRTS::join_steered(RRTNode *f)
 214 {
 215         while (this->steered().size() > 0) {
 216                 this->store_node(this->steered().front());
 217                 RRTNode *t = &this->nodes().back();
 218                 t->p(f);
 219                 t->c(this->cost_build(*f, *t));
 220                 this->steered().erase(this->steered().begin());
 221                 f = t;
 222         }
 223 }
 224
 225 bool RRTS::goal_found(RRTNode &f)
 226 {
 227         bool found = false;
 228         auto &g = this->goals().front();
 229         bool in_zone = false;
 230         double cost = this->cost_build(f, g);
 231         // TODO find if ``f`` in ``g``'s zone.
 232         double h_d = f.h() - g.h();
 233         if (h_d < -M_PI/2 || h_d > M_PI/2)
 234                 return false;
 235         double max_dist = g.mtr() * 2 * sin(M_PI/2 / 2); // mtr circle chord
 236         if (sqrt(pow(f.x() - g.x(), 2) + pow(f.y() - g.y(), 2)) > max_dist)
 237                 return false;
 238         double x_mtr = g.ccr().x();
 239         double y_mtr = g.ccr().y();
 240         if (h_d > 0) {
 241                 x_mtr = g.ccl().x();
 242                 y_mtr = g.ccl().y();
 243         }
 244         BicycleCar zone_border(g);
 245         zone_border.rotate(x_mtr, y_mtr, h_d);
 246         // zone_border.h() == f.h() now
 247         if (in_zone) {
 248                 found = true;
 249                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 250                         g.p(&f);
 251                         g.c(cost);
 252                 }
 253         }
 254         return found;
 255 }
 256
 257 // RRT* procedures
 258 bool RRTS::connect()
 259 {
 260         RRTNode *t = &this->steered().front();
 261         RRTNode *f = this->nn(this->samples().back());
 262         double cost = this->cost_search(*f, *t);
 263         for (auto n: this->nv(*t)) {
 264                 if (
 265                         !std::get<0>(this->collide_two_nodes(*n, *t))
 266                         && this->cost_search(*n, *t) < cost
 267                 ) {
 268                         f = n;
 269                         cost = this->cost_search(*n, *t);
 270                 }
 271         }
 272         this->store_node(this->steered().front());
 273         t = &this->nodes().back();
 274         t->p(f);
 275         t->c(this->cost_build(*f, *t));
 276         t->set_t(RRTNodeType::connected);
 277         return true;
 278 }
 279
 280 void RRTS::rewire()
 281 {
 282         RRTNode *f = &this->nodes().back();
 283         for (auto n: this->nv(*f)) {
 284                 if (
 285                         !std::get<0>(this->collide_two_nodes(*f, *n))
 286                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 287                 ) {
 288                         n->p(f);
 289                         n->c(this->cost_build(*f, *n));
 290                 }
 291         }
 292 }
 293
 294 // API
 295 void RRTS::init()
 296 {
 297 }
 298
 299 void RRTS::deinit()
 300 {
 301         this->nodes().clear();
 302         this->samples().clear();
 303         this->steered().clear();
 304         this->store_node(RRTNode()); // root
 305         this->icnt_ = 0;
 306         this->scnt_ = 0;
 307         this->pcnt_ = 0;
 308         this->gf_ = false;
 309 }
 310
 311 std::vector<RRTNode *> RRTS::path()
 312 {
 313         std::vector<RRTNode *> path;
 314         if (this->goals().size() == 0)
 315                 return path;
 316         RRTNode *goal = &this->goals().front();
 317         if (goal->p() == nullptr)
 318                 return path;
 319         while (goal != nullptr) {
 320                 path.push_back(goal);
 321                 goal = goal->p();
 322         }
 323         std::reverse(path.begin(), path.end());
 324         return path;
 325 }
 326
 327 bool RRTS::next()
 328 {
 329         if (this->icnt_ == 0)
 330                 this->tstart_ = std::chrono::high_resolution_clock::now();
 331         bool next = true;
 332         if (this->should_stop())
 333                 return false;
 334         this->sample();
 335         this->steer(
 336                 *this->nn(this->samples().back()),
 337                 this->samples().back()
 338         );
 339         if (std::get<0>(this->collide_steered_from(
 340                 *this->nn(this->samples().back())
 341         )))
 342                 return next;
 343         if (!this->connect())
 344                 return next;
 345         this->rewire();
 346         unsigned scnt = this->steered().size();
 347         this->steered().erase(this->steered().begin());
 348         this->join_steered(&this->nodes().back());
 349         RRTNode *just_added = &this->nodes().back();
 350         while (scnt > 0) {
 351                 scnt--;
 352                 auto &g = this->goals().front();
 353                 this->steer(*just_added, g);
 354                 if (std::get<0>(this->collide_steered_from(
 355                         *just_added
 356                 )))
 357                         continue;
 358                 this->join_steered(just_added);
 359                 this->gf(this->goal_found(this->nodes().back()));
 360                 just_added = just_added->p();
 361         }
 362         return next;
 363 }
 364
 365 void RRTS::set_sample_normal(
 366         double mx, double dx,
 367         double my, double dy,
 368         double mh, double dh
 369 )
 370 {
 371         this->ndx_ = std::normal_distribution<double>(mx, dx);
 372         this->ndy_ = std::normal_distribution<double>(my, dy);
 373         this->ndh_ = std::normal_distribution<double>(mh, dh);
 374 }
 375 void RRTS::set_sample_uniform(
 376         double xmin, double xmax,
 377         double ymin, double ymax,
 378         double hmin, double hmax
 379 )
 380 {
 381         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 382         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 383         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 384 }
 385 void RRTS::set_sample(
 386         double x1, double x2,
 387         double y1, double y2,
 388         double h1, double h2
 389 )
 390 {
 391         switch (this->sample_dist_type()) {
 392         case 1:
 393                 x1 += this->nodes().front().x();
 394                 x2 += this->nodes().front().x();
 395                 y1 += this->nodes().front().y();
 396                 y2 += this->nodes().front().y();
 397                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 398                 break;
 399         default:
 400                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 401         }
 402 }
 403
 404 Json::Value RRTS::json()
 405 {
 406         Json::Value jvo;
 407         {
 408                 jvo["time"] = this->scnt();
 409         }
 410         {
 411                 jvo["iterations"] = this->icnt();
 412         }
 413         {
 414                 jvo["init"][0] = this->nodes().front().x();
 415                 jvo["init"][1] = this->nodes().front().y();
 416                 jvo["init"][2] = this->nodes().front().h();
 417         }
 418         {
 419                 if (this->path().size() > 0) {
 420                         jvo["cost"] = cc(*this->path().back());
 421                         jvo["goal"][0] = this->path().back()->x();
 422                         jvo["goal"][1] = this->path().back()->y();
 423                         jvo["goal"][2] = this->path().back()->h();
 424                 }
 425         }
 426         {
 427                 unsigned int cu = 0;
 428                 unsigned int co = 0;
 429                 unsigned int pcnt = 0;
 430                 for (auto n: this->path()) {
 431                         jvo["path"][pcnt][0] = n->x();
 432                         jvo["path"][pcnt][1] = n->y();
 433                         jvo["path"][pcnt][2] = n->h();
 434                         if (n->t(RRTNodeType::cusp))
 435                                 cu++;
 436                         if (n->t(RRTNodeType::connected))
 437                                 co++;
 438                         pcnt++;
 439                 }
 440                 jvo["cusps-in-path"] = cu;
 441                 jvo["connecteds-in-path"] = co;
 442         }
 443         {
 444                 unsigned int gcnt = 0;
 445                 for (auto g: this->goals()) {
 446                         jvo["goals"][gcnt][0] = g.x();
 447                         jvo["goals"][gcnt][1] = g.y();
 448                         jvo["goals"][gcnt][2] = g.h();
 449                         gcnt++;
 450                 }
 451         }
 452         {
 453                 unsigned int ocnt = 0;
 454                 for (auto o: this->obstacles()) {
 455                         unsigned int ccnt = 0;
 456                         for (auto c: o.poly()) {
 457                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 458                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 459                                 ccnt++;
 460                         }
 461                         ocnt++;
 462                 }
 463         }
 464         {
 465                 jvo["nodes"] = (unsigned int) this->nodes().size();
 466         }
 467         //{
 468         //        unsigned int ncnt = 0;
 469         //        for (auto n: this->nodes()) {
 470         //                jvo["nodes_x"][ncnt] = n.x();
 471         //                jvo["nodes_y"][ncnt] = n.y();
 472         //                //jvo["nodes_h"][ncnt] = n.h();
 473         //                ncnt++;
 474         //        }
 475         //}
 476         return jvo;
 477 }
 478
 479 void RRTS::json(Json::Value jvi)
 480 {
 481         assert(jvi["init"] != Json::nullValue);
 482         assert(jvi["goal"] != Json::nullValue);
 483         assert(jvi["goals"] != Json::nullValue);
 484         assert(jvi["obst"] != Json::nullValue);
 485
 486         this->nodes().front().x(jvi["init"][0].asDouble());
 487         this->nodes().front().y(jvi["init"][1].asDouble());
 488         this->nodes().front().h(jvi["init"][2].asDouble());
 489         {
 490                 RRTNode tmp_node;
 491                 tmp_node.x(jvi["goal"][0].asDouble());
 492                 tmp_node.y(jvi["goal"][1].asDouble());
 493                 tmp_node.h(jvi["goal"][2].asDouble());
 494                 this->goals().push_back(tmp_node);
 495                 for (auto g: jvi["goals"]) {
 496                         tmp_node.x(g[0].asDouble());
 497                         tmp_node.y(g[1].asDouble());
 498                         tmp_node.h(g[2].asDouble());
 499                         this->goals().push_back(tmp_node);
 500                 }
 501         }
 502         {
 503                 Obstacle tmp_obstacle;
 504                 for (auto o: jvi["obst"]) {
 505                         tmp_obstacle.poly().clear();
 506                         for (auto c: o) {
 507                                 double tmp_x = c[0].asDouble();
 508                                 double tmp_y = c[1].asDouble();
 509                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 510                                 tmp_obstacle.poly().push_back(tmp_tuple);
 511                         }
 512                         this->obstacles().push_back(tmp_obstacle);
 513                 }
 514         }
 515         {
 516                 double edist_init_goal = sqrt(
 517                         pow(
 518                                 this->nodes().front().x()
 519                                 - this->goals().front().x(),
 520                                 2
 521                         )
 522                         + pow(
 523                                 this->nodes().front().y()
 524                                 - this->goals().front().y(),
 525                                 2
 526                         )
 527                 );
 528                 this->set_sample(
 529                         this->nodes().front().x(), edist_init_goal,
 530                         this->nodes().front().y(), edist_init_goal,
 531                         0, 2 * M_PI
 532                 );
 533         }
 534 }
 535
 536 RRTS::RRTS()
 537         : gen_(std::random_device{}())
 538 {
 539         this->goals().reserve(100);
 540         this->nodes().reserve(4000000);
 541         this->samples().reserve(1000);
 542         this->steered().reserve(20000);
 543         this->store_node(RRTNode()); // root
 544 }
 545
 546 double cc(RRTNode &t)
 547 {
 548         RRTNode *n = &t;
 549         double cost = 0;
 550         while (n != nullptr) {
 551                 cost += n->c();
 552                 n = n->p();
 553         }
 554         return cost;
 555 }