CircularGenerator.cpp 21.5 KB
Newer Older
1 2
#include "CircularGenerator.h"

3
#include "JsonHelper.h"
4
#include "QGCLoggingCategory.h"
5
#include "SettingsFact.h"
6 7

#define CLIPPER_SCALE 1000000
8 9 10 11 12 13 14 15
#include "RoutingThread.h"
#include "geometry/GenericCircle.h"
#include "geometry/MeasurementArea.h"
#include "geometry/SafeArea.h"
#include "geometry/clipper/clipper.hpp"
#include "nemo_interface/SnakeTile.h"

QGC_LOGGING_CATEGORY(CircularGeneratorLog, "CircularGeneratorLog")
16 17 18 19 20 21

using namespace ClipperLib;
template <> inline auto get<0>(const IntPoint &p) { return p.X; }
template <> inline auto get<1>(const IntPoint &p) { return p.Y; }

namespace routing {
22 23

namespace {
24 25 26 27
GeneratorBase *creator(QObject *parent) {
  return new CircularGenerator(parent);
}

28 29 30 31 32 33
const char *distanceKey = "TransectDistance";
const char *deltaAlphaKey = "DeltaAlpha";
const char *minLengthKey = "MinLength";
const char *referenceKey = "ReferencePoint";
} // namespace

34 35 36 37 38 39 40
bool circularTransects(const snake::FPoint &reference,
                       const snake::FPolygon &polygon,
                       const std::vector<snake::FPolygon> &tiles,
                       snake::Length deltaR, snake::Angle deltaAlpha,
                       snake::Length minLength, snake::Transects &transects);

const char *CircularGenerator::settingsGroup = "CircularGenerator";
41 42 43
const char *CircularGenerator::typeString = "CircularGenerator";

REGISTER_GENERATOR(CircularGenerator::typeString, creator)
44 45

CircularGenerator::CircularGenerator(QObject *parent)
46 47 48 49 50 51 52 53 54
    : GeneratorBase(parent),
      _metaDataMap(FactMetaData::createMapFromJsonFile(
          QStringLiteral(":/json/CircularGenerator.SettingsGroup.json"), this)),
      _distance(settingsGroup, _metaDataMap[distanceKey]),
      _deltaAlpha(settingsGroup, _metaDataMap[deltaAlphaKey]),
      _minLength(settingsGroup, _metaDataMap[minLengthKey]),
      _measurementArea(nullptr) {
  init();
}
55 56

CircularGenerator::CircularGenerator(GeneratorBase::Data d, QObject *parent)
57
    : GeneratorBase(d, parent),
58 59
      _metaDataMap(FactMetaData::createMapFromJsonFile(
          QStringLiteral(":/json/CircularGenerator.SettingsGroup.json"), this)),
60 61 62
      _distance(settingsGroup, _metaDataMap[distanceKey]),
      _deltaAlpha(settingsGroup, _metaDataMap[deltaAlphaKey]),
      _minLength(settingsGroup, _metaDataMap[minLengthKey]),
63
      _measurementArea(nullptr) {
64
  init();
65 66
}

67
QString CircularGenerator::editorQml() const {
68 69 70
  return QStringLiteral("CircularGeneratorEditor.qml");
}

71
QString CircularGenerator::mapVisualQml() const {
72 73 74
  return QStringLiteral("CircularGeneratorMapVisual.qml");
}

75
QString CircularGenerator::abbreviation() const { return tr("C. Gen."); }
76

77
QString CircularGenerator::type() const { return typeString; }
78 79 80

bool CircularGenerator::get(Generator &generator) {
  if (this->_d) {
81
    if (this->_d->isCorrect()) {
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98
      // Prepare data.
      auto origin = this->_d->origin();
      origin.setAltitude(0);
      if (!origin.isValid()) {
        qCDebug(CircularGeneratorLog) << "get(): origin invalid." << origin;
        return false;
      }

      auto ref = this->_reference;
      ref.setAltitude(0);
      if (!ref.isValid()) {
        qCDebug(CircularGeneratorLog) << "get(): reference invalid." << ref;
        return false;
      }
      snake::FPoint reference;
      snake::toENU(origin, ref, reference);

99 100 101 102 103 104 105
      auto measurementArea =
          getGeoArea<const MeasurementArea *>(*this->_d->areaList());
      if (measurementArea == nullptr) {
        qCDebug(CircularGeneratorLog) << "get(): measurement area == nullptr";
        return false;
      }
      auto geoPolygon = measurementArea->coordinateList();
106 107 108 109 110 111 112 113 114 115 116 117 118 119 120
      for (auto &v : geoPolygon) {
        if (v.isValid()) {
          v.setAltitude(0);
        } else {
          qCDebug(CircularGeneratorLog) << "get(): measurement area invalid.";
          for (const auto &w : geoPolygon) {
            qCDebug(CircularGeneratorLog) << w;
          }
          return false;
        }
      }
      auto pPolygon = std::make_shared<snake::FPolygon>();
      snake::areaToEnu(origin, geoPolygon, *pPolygon);

      // Progress and tiles.
121 122
      const auto &progress = measurementArea->progress();
      const auto *tiles = measurementArea->tiles();
123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
      auto pTiles = std::make_shared<std::vector<snake::FPolygon>>();
      if (progress.size() == tiles->count()) {
        for (int i = 0; i < tiles->count(); ++i) {
          if (progress[i] == 100) {
            const auto *obj = (*tiles)[int(i)];
            const auto *tile = qobject_cast<const SnakeTile *>(obj);

            if (tile != nullptr) {
              snake::FPolygon tileENU;
              snake::areaToEnu(origin, tile->coordinateList(), tileENU);
              pTiles->push_back(std::move(tileENU));
            } else {
              qCDebug(CircularGeneratorLog)
                  << "get(): progress.size() != tiles->count().";
              return false;
            }
          }
        }
      } else {
        qCDebug(CircularGeneratorLog)
            << "get(): progress.size() != tiles->count().";
        return false;
      }

147 148 149 150 151 152
      auto serviceArea = getGeoArea<const SafeArea *>(*this->_d->areaList());
      if (measurementArea == nullptr) {
        qCDebug(CircularGeneratorLog) << "get(): measurement area == nullptr";
        return false;
      }
      auto geoDepot = serviceArea->depot();
153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194
      if (!geoDepot.isValid()) {
        qCDebug(CircularGeneratorLog) << "get(): depot invalid." << geoDepot;
        return false;
      }
      snake::FPoint depot;
      snake::toENU(origin, geoDepot, depot);

      // Fetch transect parameter.
      auto distance =
          snake::Length(this->_distance.rawValue().toDouble() * bu::si::meter);
      auto minLength =
          snake::Length(this->_minLength.rawValue().toDouble() * bu::si::meter);
      auto alpha = snake::Angle(this->_deltaAlpha.rawValue().toDouble() *
                                bu::degree::degree);

      generator = [reference, depot, pPolygon, pTiles, distance, alpha,
                   minLength](snake::Transects &transects) -> bool {
        bool value = circularTransects(reference, *pPolygon, *pTiles, distance,
                                       alpha, minLength, transects);
        transects.insert(transects.begin(), snake::FLineString{depot});
        return value;
      };
      return true;
    } else {
      qCDebug(CircularGeneratorLog) << "get(): data invalid.";
      return false;
    }
  } else {
    qCDebug(CircularGeneratorLog) << "get(): data member not set.";
    return false;
  }
}

QGeoCoordinate CircularGenerator::reference() const { return _reference; }

void CircularGenerator::setReference(const QGeoCoordinate &reference) {
  if (_reference != reference) {
    _reference = reference;
    emit referenceChanged();
  }
}

195
bool CircularGenerator::save(QJsonObject &obj) const {
196 197
  QJsonObject temp;

198 199
  GeneratorBase::save(temp);

200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
  bool ok = false;
  auto variant = _distance.rawValue();
  auto val = variant.toDouble(&ok);
  if (!ok) {
    qCDebug(CircularGeneratorLog)
        << "save(): not able to save distance. Not a double: "
        << variant.typeName();
    return false;
  } else {
    temp[distanceKey] = val;
  }

  variant = _deltaAlpha.rawValue();
  val = variant.toDouble(&ok);
  if (!ok) {
    qCDebug(CircularGeneratorLog)
        << "save(): not able to save deltaAlpha. Not a double: "
        << variant.typeName();
    return false;
  } else {
    temp[deltaAlphaKey] = val;
  }

  variant = _minLength.rawValue();
  val = variant.toDouble(&ok);
  if (!ok) {
    qCDebug(CircularGeneratorLog)
        << "save(): not able to save minLength. Not a double: "
        << variant.typeName();
    return false;
  } else {
    temp[minLengthKey] = val;
  }

  QJsonValue jsonReference;
  JsonHelper::saveGeoCoordinate(_reference, false, jsonReference);
  temp[referenceKey] = jsonReference;

  obj = std::move(temp);
239 240 241
  return true;
}

242 243 244
bool CircularGenerator::load(const QJsonObject &obj, QString &errorString) {
  bool returnValue = true;

245 246 247 248 249 250 251 252
  {
    QString e;
    if (!GeneratorBase::load(obj, e)) {
      returnValue = false;
      errorString.append(e);
    }
  }

253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320
  // load distance
  {
    QString e;
    QList<JsonHelper::KeyValidateInfo> keyInfo = {
        {distanceKey, QJsonValue::Double, true},
    };
    if (JsonHelper::validateKeys(obj, keyInfo, e)) {
      _distance.setRawValue(obj[distanceKey]);
    } else {
      returnValue = false;
      errorString.append(e);
      errorString.append("\n");
    }
  }

  // load deltaAlpha
  {
    QString e;
    QList<JsonHelper::KeyValidateInfo> keyInfo = {
        {deltaAlphaKey, QJsonValue::Double, true},
    };
    if (JsonHelper::validateKeys(obj, keyInfo, e)) {
      _deltaAlpha.setRawValue(obj[deltaAlphaKey]);
    } else {
      returnValue = false;
      errorString.append(e);
      errorString.append("\n");
    }
  }

  // load distance
  {
    QString e;
    QList<JsonHelper::KeyValidateInfo> keyInfo = {
        {minLengthKey, QJsonValue::Double, true},
    };
    if (JsonHelper::validateKeys(obj, keyInfo, e)) {
      _minLength.setRawValue(obj[minLengthKey]);
    } else {
      returnValue = false;
      errorString.append(e);
      errorString.append("\n");
    }
  }

  // load reference
  {
    QString e;
    QList<JsonHelper::KeyValidateInfo> keyInfo = {
        {referenceKey, QJsonValue::Array, true},
    };
    if (JsonHelper::validateKeys(obj, keyInfo, e)) {
      QGeoCoordinate ref;
      if (JsonHelper::loadGeoCoordinate(obj[referenceKey], false, ref, e)) {
        setReference(ref);
      } else {
        returnValue = false;
        errorString.append(e);
        errorString.append("\n");
      }
    } else {
      returnValue = false;
      errorString.append(e);
      errorString.append("\n");
    }
  }

  return returnValue;
321
}
322 323 324 325 326 327 328
void CircularGenerator::resetReferenceIfInvalid() {
  if (!this->_reference.isValid()) {
    resetReference();
  }
}

void CircularGenerator::resetReference() {
329 330 331
  if (this->_d != nullptr) {
    auto measurementArea =
        getGeoArea<const MeasurementArea *>(*this->_d->areaList());
332

333 334 335 336 337 338 339
    if (measurementArea != nullptr) {
      if (measurementArea->center().isValid()) {
        setReference(measurementArea->center());
      } else {
        qCWarning(CircularGeneratorLog)
            << "measurement area center" << measurementArea->center();
      }
340
    } else {
341 342
      qCDebug(CircularGeneratorLog)
          << "resetReference(): measurement area == nullptr";
343
    }
344 345 346
  }
}

347
Fact *CircularGenerator::distance() { return &_distance; }
348

349 350 351 352 353
Fact *CircularGenerator::deltaAlpha() { return &_deltaAlpha; }

Fact *CircularGenerator::minLength() { return &_minLength; }

void CircularGenerator::onAreaListChanged() {
354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381
  if (this->_d != nullptr) {
    auto *measurementArea =
        getGeoArea<MeasurementArea *>(*this->_d->areaList());
    setMeasurementArea(measurementArea);
  }
}

void CircularGenerator::onDataChanged() {
  if (this->_d != nullptr) {
    connect(this->_d, &AreaData::areaListChanged, this,
            &CircularGenerator::onAreaListChanged);
    onAreaListChanged();
  }
}

void CircularGenerator::init() {
  connect(this->distance(), &Fact::rawValueChanged, this,
          &GeneratorBase::generatorChanged);
  connect(this->deltaAlpha(), &Fact::rawValueChanged, this,
          &GeneratorBase::generatorChanged);
  connect(this->minLength(), &Fact::rawValueChanged, this,
          &GeneratorBase::generatorChanged);
  connect(this, &CircularGenerator::referenceChanged, this,
          &GeneratorBase::generatorChanged);
  connect(this, &CircularGenerator::dataChanged, this,
          &CircularGenerator::onDataChanged);
  onDataChanged();
  setName(tr("Circular Generator"));
382 383
}

384 385
void CircularGenerator::setMeasurementArea(MeasurementArea *area) {
  if (_measurementArea != area) {
386

387 388
    if (_measurementArea != nullptr) {
      disconnect(_measurementArea, &MeasurementArea::progressChanged, this,
389
                 &GeneratorBase::generatorChanged);
390
      disconnect(_measurementArea, &MeasurementArea::tilesChanged, this,
391
                 &GeneratorBase::generatorChanged);
392
      disconnect(_measurementArea, &MeasurementArea::centerChanged, this,
393
                 &CircularGenerator::resetReferenceIfInvalid);
394
      disconnect(_measurementArea, &MeasurementArea::pathChanged, this,
395 396
                 &GeneratorBase::generatorChanged);
    }
397

398
    _measurementArea = area;
399

400 401 402 403 404 405 406 407 408 409
    if (_measurementArea != nullptr) {
      connect(_measurementArea, &MeasurementArea::progressChanged, this,
              &GeneratorBase::generatorChanged);
      connect(_measurementArea, &MeasurementArea::tilesChanged, this,
              &GeneratorBase::generatorChanged);
      connect(_measurementArea, &MeasurementArea::centerChanged, this,
              &CircularGenerator::resetReferenceIfInvalid);
      connect(_measurementArea, &MeasurementArea::pathChanged, this,
              &GeneratorBase::generatorChanged);
    }
410

411 412 413
    emit generatorChanged();
  }
}
414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632

bool circularTransects(const snake::FPoint &reference,
                       const snake::FPolygon &polygon,
                       const std::vector<snake::FPolygon> &tiles,
                       snake::Length deltaR, snake::Angle deltaAlpha,
                       snake::Length minLength, snake::Transects &transects) {
  auto s1 = std::chrono::high_resolution_clock::now();

  // Check preconitions
  if (polygon.outer().size() >= 3) {
    using namespace boost::units;
    // Convert geo polygon to ENU polygon.
    std::string error;
    // Check validity.
    if (!bg::is_valid(polygon, error)) {
      qCDebug(CircularGeneratorLog) << "circularTransects(): "
                                       "invalid polygon.";
      qCDebug(CircularGeneratorLog) << error.c_str();
      std::stringstream ss;
      ss << bg::wkt(polygon);
      qCDebug(CircularGeneratorLog) << ss.str().c_str();
    } else {
      // Calculate polygon distances and angles.
      std::vector<snake::Length> distances;
      distances.reserve(polygon.outer().size());
      std::vector<snake::Angle> angles;
      angles.reserve(polygon.outer().size());
      //#ifdef DEBUG_CIRCULAR_SURVEY
      //      qCDebug(CircularGeneratorLog) << "circularTransects():";
      //#endif
      for (const auto &p : polygon.outer()) {
        snake::Length distance = bg::distance(reference, p) * si::meter;
        distances.push_back(distance);
        snake::Angle alpha = (std::atan2(p.get<1>(), p.get<0>())) * si::radian;
        alpha = alpha < 0 * si::radian ? alpha + 2 * M_PI * si::radian : alpha;
        angles.push_back(alpha);
        //#ifdef DEBUG_CIRCULAR_SURVEY
        //        qCDebug(CircularGeneratorLog) << "distances, angles,
        //        coordinates:"; qCDebug(CircularGeneratorLog) <<
        //        to_string(distance).c_str(); qCDebug(CircularGeneratorLog)
        //        << to_string(snake::Degree(alpha)).c_str();
        //        qCDebug(CircularGeneratorLog) << "x = " << p.get<0>() << "y
        //        = "
        //        << p.get<1>();
        //#endif
      }

      auto rMin = deltaR; // minimal circle radius
      snake::Angle alpha1(0 * degree::degree);
      snake::Angle alpha2(360 * degree::degree);
      // Determine r_min by successive approximation
      if (!bg::within(reference, polygon.outer())) {
        rMin = bg::distance(reference, polygon) * si::meter;
      }

      auto rMax = (*std::max_element(distances.begin(),
                                     distances.end())); // maximal circle radius

      // Scale parameters and coordinates.
      const auto rMinScaled =
          ClipperLib::cInt(std::round(rMin.value() * CLIPPER_SCALE));
      const auto deltaRScaled =
          ClipperLib::cInt(std::round(deltaR.value() * CLIPPER_SCALE));
      auto referenceScaled = ClipperLib::IntPoint{
          ClipperLib::cInt(std::round(reference.get<0>() * CLIPPER_SCALE)),
          ClipperLib::cInt(std::round(reference.get<1>() * CLIPPER_SCALE))};

      // Generate circle sectors.
      auto rScaled = rMinScaled;
      const auto nTran = long(std::ceil(((rMax - rMin) / deltaR).value()));
      vector<ClipperLib::Path> sectors(nTran, ClipperLib::Path());
      const auto nSectors =
          long(std::round(((alpha2 - alpha1) / deltaAlpha).value()));
      //#ifdef DEBUG_CIRCULAR_SURVEY
      //      qCDebug(CircularGeneratorLog) << "circularTransects(): sector
      //      parameres:"; qCDebug(CircularGeneratorLog) << "alpha1: " <<
      //      to_string(snake::Degree(alpha1)).c_str();
      //      qCDebug(CircularGeneratorLog) << "alpha2:
      //      "
      //      << to_string(snake::Degree(alpha2)).c_str();
      //      qCDebug(CircularGeneratorLog) << "n: "
      //      << to_string((alpha2 - alpha1) / deltaAlpha).c_str();
      //      qCDebug(CircularGeneratorLog)
      //      << "nSectors: " << nSectors; qCDebug(CircularGeneratorLog) <<
      //      "rMin: " << to_string(rMin).c_str();
      //      qCDebug(CircularGeneratorLog)
      //      << "rMax: " << to_string(rMax).c_str();
      //      qCDebug(CircularGeneratorLog) << "nTran: " << nTran;
      //#endif
      using ClipperCircle =
          GenericCircle<ClipperLib::cInt, ClipperLib::IntPoint>;
      for (auto &sector : sectors) {
        ClipperCircle circle(rScaled, referenceScaled);
        approximate(circle, nSectors, sector);
        rScaled += deltaRScaled;
      }
      // Clip sectors to polygonENU.
      ClipperLib::Path polygonClipper;
      snake::FPolygon shrinked;
      snake::offsetPolygon(polygon, shrinked, -0.3);
      auto &outer = shrinked.outer();
      polygonClipper.reserve(outer.size());
      for (auto it = outer.begin(); it < outer.end() - 1; ++it) {
        auto x = ClipperLib::cInt(std::round(it->get<0>() * CLIPPER_SCALE));
        auto y = ClipperLib::cInt(std::round(it->get<1>() * CLIPPER_SCALE));
        polygonClipper.push_back(ClipperLib::IntPoint{x, y});
      }
      ClipperLib::Clipper clipper;
      clipper.AddPath(polygonClipper, ClipperLib::ptClip, true);
      clipper.AddPaths(sectors, ClipperLib::ptSubject, false);
      ClipperLib::PolyTree transectsClipper;
      clipper.Execute(ClipperLib::ctIntersection, transectsClipper,
                      ClipperLib::pftNonZero, ClipperLib::pftNonZero);

      // Subtract holes.
      if (tiles.size() > 0) {
        vector<ClipperLib::Path> processedTiles;
        for (const auto &tile : tiles) {
          ClipperLib::Path path;
          for (const auto &v : tile.outer()) {
            path.push_back(ClipperLib::IntPoint{
                static_cast<ClipperLib::cInt>(v.get<0>() * CLIPPER_SCALE),
                static_cast<ClipperLib::cInt>(v.get<1>() * CLIPPER_SCALE)});
          }
          processedTiles.push_back(std::move(path));
        }

        clipper.Clear();
        for (const auto &child : transectsClipper.Childs) {
          clipper.AddPath(child->Contour, ClipperLib::ptSubject, false);
        }
        clipper.AddPaths(processedTiles, ClipperLib::ptClip, true);
        transectsClipper.Clear();
        clipper.Execute(ClipperLib::ctDifference, transectsClipper,
                        ClipperLib::pftNonZero, ClipperLib::pftNonZero);
      }

      // Extract transects from  PolyTree and convert them to
      // BoostLineString
      for (const auto &child : transectsClipper.Childs) {
        snake::FLineString transect;
        transect.reserve(child->Contour.size());
        for (const auto &vertex : child->Contour) {
          auto x = static_cast<double>(vertex.X) / CLIPPER_SCALE;
          auto y = static_cast<double>(vertex.Y) / CLIPPER_SCALE;
          transect.push_back(snake::FPoint(x, y));
        }
        transects.push_back(transect);
      }

      // Join sectors which where slit due to clipping.
      const double th = 0.01;
      for (auto ito = transects.begin(); ito < transects.end(); ++ito) {
        for (auto iti = ito + 1; iti < transects.end(); ++iti) {
          auto dist1 = bg::distance(ito->front(), iti->front());
          if (dist1 < th) {
            snake::FLineString temp;
            for (auto it = iti->end() - 1; it >= iti->begin(); --it) {
              temp.push_back(*it);
            }
            temp.insert(temp.end(), ito->begin(), ito->end());
            *ito = temp;
            transects.erase(iti);
            break;
          }
          auto dist2 = bg::distance(ito->front(), iti->back());
          if (dist2 < th) {
            snake::FLineString temp;
            temp.insert(temp.end(), iti->begin(), iti->end());
            temp.insert(temp.end(), ito->begin(), ito->end());
            *ito = temp;
            transects.erase(iti);
            break;
          }
          auto dist3 = bg::distance(ito->back(), iti->front());
          if (dist3 < th) {
            snake::FLineString temp;
            temp.insert(temp.end(), ito->begin(), ito->end());
            temp.insert(temp.end(), iti->begin(), iti->end());
            *ito = temp;
            transects.erase(iti);
            break;
          }
          auto dist4 = bg::distance(ito->back(), iti->back());
          if (dist4 < th) {
            snake::FLineString temp;
            temp.insert(temp.end(), ito->begin(), ito->end());
            for (auto it = iti->end() - 1; it >= iti->begin(); --it) {
              temp.push_back(*it);
            }
            *ito = temp;
            transects.erase(iti);
            break;
          }
        }
      }

      // Remove short transects
      for (auto it = transects.begin(); it < transects.end();) {
        if (bg::length(*it) < minLength.value()) {
          it = transects.erase(it);
        } else {
          ++it;
        }
      }

      qCDebug(CircularGeneratorLog)
          << "circularTransects(): transect gen. time: "
          << std::chrono::duration_cast<std::chrono::milliseconds>(
                 std::chrono::high_resolution_clock::now() - s1)
                 .count()
          << " ms";
      return true;
    }
  }
  return false;
}

} // namespace routing