Example: maps_voxelmap_simple

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2024, 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/gui/CDisplayWindow3D.h>
#include <mrpt/maps/CVoxelMap.h>
#include <mrpt/obs/CObservation2DRangeScan.h>
#include <mrpt/obs/stock_observations.h>
#include <mrpt/opengl/CGridPlaneXY.h>
#include <mrpt/opengl/COctoMapVoxels.h>
#include <mrpt/opengl/stock_objects.h>
#include <mrpt/system/os.h>

#include <chrono>
#include <iostream>
#include <thread>

// ------------------------------------------------------
//              TestVoxelMap
// ------------------------------------------------------
void TestVoxelMap()
{
    mrpt::maps::CVoxelMap map(0.1);

    // map.insertionOptions.max_range = 5.0;  // [m]

    // Manually update voxels:
    if (false)
    {
        map.updateVoxel(1, 1, 1, true);  // integrate 'occupied' measurement

        map.updateVoxel(1.5, 1, 1, true);  // integrate 'occupied' measurement
        map.updateVoxel(1.5, 1, 1, true);  // integrate 'occupied' measurement
        map.updateVoxel(1.5, 1, 1, true);  // integrate 'occupied' measurement

        map.updateVoxel(-1, -1, 1, false);  // integrate 'free' measurement

        double occup;
        bool is_mapped;
        mrpt::math::TPoint3D pt;

        pt = mrpt::math::TPoint3D(1, 1, 1);
        is_mapped = map.getPointOccupancy(pt.x, pt.y, pt.z, occup);
        std::cout << "pt: " << pt
                  << " is mapped?: " << (is_mapped ? "YES" : "NO")
                  << " occupancy: " << occup << std::endl;

        pt = mrpt::math::TPoint3D(-1, -1, 1);
        is_mapped = map.getPointOccupancy(pt.x, pt.y, pt.z, occup);
        std::cout << "pt: " << pt
                  << " is mapped?: " << (is_mapped ? "YES" : "NO")
                  << " occupancy: " << occup << std::endl;
    }

    // Insert 2D scan:
    if (true)
    {
        mrpt::obs::CObservation2DRangeScan scan1;
        mrpt::obs::stock_observations::example2DRangeScan(scan1);
        map.insertObservation(scan1);
    }

    mrpt::gui::CDisplayWindow3D win("VoxelMap demo", 640, 480);

    auto gl_map = mrpt::opengl::COctoMapVoxels::Create();

    {
        mrpt::opengl::Scene::Ptr& scene = win.get3DSceneAndLock();

        {
            auto gl_grid =
                mrpt::opengl::CGridPlaneXY::Create(-20, 20, -20, 20, 0, 1);
            gl_grid->setColor_u8(mrpt::img::TColor(0x80, 0x80, 0x80));
            scene->insert(gl_grid);
        }
        scene->insert(mrpt::opengl::stock_objects::CornerXYZSimple());

        map.getAsOctoMapVoxels(*gl_map);

        // View occupied points:
        {
            auto mapPts = map.getOccupiedVoxels();
            mapPts->renderOptions.point_size = 5.0;
            scene->insert(mapPts->getVisualization());
        }

        gl_map->showGridLines(false);
        gl_map->showVoxels(mrpt::opengl::VOXEL_SET_OCCUPIED, true);
        gl_map->showVoxels(mrpt::opengl::VOXEL_SET_FREESPACE, true);
        scene->insert(gl_map);

        win.unlockAccess3DScene();
    }

    std::cout << "Close the window to exit" << std::endl;

    bool update_msg = true;

    while (win.isOpen())
    {
        if (win.keyHit())
        {
            const unsigned int k = win.getPushedKey();

            switch (k)
            {
                case 'g':
                case 'G':
                    gl_map->showGridLines(!gl_map->areGridLinesVisible());
                    break;
                case 'f':
                case 'F':
                    gl_map->showVoxels(
                        mrpt::opengl::VOXEL_SET_FREESPACE,
                        !gl_map->areVoxelsVisible(
                            mrpt::opengl::VOXEL_SET_FREESPACE));
                    break;
                case 'o':
                case 'O':
                    gl_map->showVoxels(
                        mrpt::opengl::VOXEL_SET_OCCUPIED,
                        !gl_map->areVoxelsVisible(
                            mrpt::opengl::VOXEL_SET_OCCUPIED));
                    break;
                case 'l':
                case 'L':
                    gl_map->enableLights(!gl_map->areLightsEnabled());
                    break;
            };
            update_msg = true;
        }

        if (update_msg)
        {
            update_msg = false;

            win.addTextMessage(
                5, 5,
                mrpt::format(
                    "Commands: 'f' (freespace=%s) | 'o' (occupied=%s) | 'l' "
                    "(lights=%s)",
                    gl_map->areVoxelsVisible(mrpt::opengl::VOXEL_SET_FREESPACE)
                        ? "YES"
                        : "NO",
                    gl_map->areVoxelsVisible(mrpt::opengl::VOXEL_SET_OCCUPIED)
                        ? "YES"
                        : "NO",
                    gl_map->areLightsEnabled() ? "YES" : "NO"));

            win.repaint();
        }

        using namespace std::chrono_literals;
        std::this_thread::sleep_for(10ms);
    };
}

int main([[maybe_unused]] int argc, [[maybe_unused]] char** argv)
{
    try
    {
        TestVoxelMap();
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cout << "Exception: " << e.what() << std::endl;
        return -1;
    }
}