Example: slam_range_only_localization_rej_sampling_example

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2021, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */

#include <mrpt/config/CConfigFile.h>
#include <mrpt/maps/CLandmarksMap.h>
#include <mrpt/maps/CMultiMetricMap.h>
#include <mrpt/obs/CObservationBeaconRanges.h>
#include <mrpt/random.h>
#include <mrpt/slam/CRejectionSamplingRangeOnlyLocalization.h>
#include <mrpt/system/CTicTac.h>
#include <mrpt/system/os.h>

#include <iostream>

using namespace mrpt;
using namespace mrpt::slam;
using namespace mrpt::maps;
using namespace mrpt::system;
using namespace mrpt::random;
using namespace mrpt::poses;
using namespace mrpt::config;
using namespace std;

float SIGMA = 0.03f;

// ------------------------------------------------------
//              TestRS
// ------------------------------------------------------
void TestRS()
{
    getRandomGenerator().randomize();

    // Load the map:
    CMultiMetricMap map;
    mrpt::maps::TSetOfMetricMapInitializers mapInit;
    mapInit.loadFromConfigFile(CConfigFile("_demo_map.ini"), "MetricMap");
    map.setListOfMaps(mapInit);

    // Create a dummy observation:
    mrpt::obs::CObservationBeaconRanges obs;
    mrpt::obs::CObservationBeaconRanges::TMeasurement meas;
    obs.stdError = SIGMA;

    meas.beaconID = 0;
    meas.sensedDistance = 2.1f;
    meas.sensorLocationOnRobot = CPoint3D(0, 0, 0);
    obs.sensedData.push_back(meas);

    meas.beaconID = 1;
    meas.sensedDistance = 3.1f;
    meas.sensorLocationOnRobot = CPoint3D(0, 0, 0);
    obs.sensedData.push_back(meas);

    meas.beaconID = 2;
    meas.sensedDistance = 1.1f;
    meas.sensorLocationOnRobot = CPoint3D(0, 0, 0);
    //  obs.sensedData.push_back( meas );

    // Rejection Sampling:
    CRejectionSamplingRangeOnlyLocalization RS;
    vector<CRejectionSamplingRangeOnlyLocalization::TParticle> samples;
    CTicTac tictac;

    // Set data:
    auto lmMap = map.mapByClass<CLandmarksMap>();
    ASSERT_(lmMap);

    printf("Preparing...");
    tictac.Tic();
    CPose2D dumPose(0, 0, 0);
    RS.setParams(*lmMap, obs, SIGMA, dumPose);
    printf("Ok! %fms\n", 1000 * tictac.Tac());

    printf("Computing...");
    tictac.Tic();
    RS.rejectionSampling(1000, samples, 1000);
    printf("Ok! %fms\n", 1000 * tictac.Tac());

    FILE* f = os::fopen("_out_samples.txt", "wt");
    vector<CRejectionSamplingRangeOnlyLocalization::TParticle>::iterator it;
    for (it = samples.begin(); it != samples.end(); it++)
        os::fprintf(
            f, "%f %f %f %e\n", it->d->x(), it->d->y(), it->d->phi(),
            it->log_w);

    os::fclose(f);
}

// ------------------------------------------------------
//                      MAIN
// ------------------------------------------------------
int main()
{
    try
    {
        TestRS();

        return 0;
    }
    catch (exception& e)
    {
        std::cerr << "MRPT error: " << mrpt::exception_to_str(e) << std::endl;
        return -1;
    }
    catch (...)
    {
        printf("Untyped excepcion!!");
        return -1;
    }
}