apps/icp-log-viewer/main.cpp

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/* -------------------------------------------------------------------------
 *  A repertory of multi primitive-to-primitive (MP2P) ICP algorithms in C++
 * Copyright (C) 2018-2024 Jose Luis Blanco, University of Almeria
 * See LICENSE for license information.
 * ------------------------------------------------------------------------- */
 
// The goal is to visualize these guys:
#include <mp2p_icp/LogRecord.h>
// using this:
#include <mrpt/gui/CDisplayWindowGUI.h>
 
// other deps:
#include <mrpt/3rdparty/tclap/CmdLine.h>
#include <mrpt/config.h>
#include <mrpt/config/CConfigFile.h>
#include <mrpt/core/round.h>
#include <mrpt/opengl/CEllipsoid3D.h>
#include <mrpt/opengl/CGridPlaneXY.h>
#include <mrpt/opengl/COpenGLScene.h>
#include <mrpt/opengl/stock_objects.h>
#include <mrpt/poses/CPosePDFGaussian.h>
#include <mrpt/poses/Lie/SO.h>
#include <mrpt/system/CDirectoryExplorer.h>
#include <mrpt/system/filesystem.h>
#include <mrpt/system/os.h>
#include <mrpt/system/progress.h>
#include <mrpt/system/string_utils.h>  // unitsFormat()
 
#include <iostream>
 
#include "../libcfgpath/cfgpath.h"
 
constexpr const char* APP_NAME           = "icp-log-viewer";
constexpr int         MID_FONT_SIZE      = 14;
constexpr int         SMALL_FONT_SIZE    = 12;
constexpr int         WINDOW_FIXED_WIDTH = 400;
 
// =========== Declare supported cli switches ===========
static TCLAP::CmdLine cmd(APP_NAME);
 
static TCLAP::ValueArg<std::string> argExtension(
    "e", "file-extension", "Filename extension to look for. Default is `icplog`", false, "icplog",
    "icplog", cmd);
 
static TCLAP::ValueArg<std::string> argSearchDir(
    "d", "directory", "Directory in which to search for *.icplog files.", false, ".", ".", cmd);
 
static TCLAP::ValueArg<std::string> argSingleFile(
    "f", "file", "Load just this one single log *.icplog file.", false, "log.icplog", "log.icplog",
    cmd);
 
static TCLAP::ValueArg<std::string> arg_plugins(
    "l", "load-plugins", "One or more (comma separated) *.so files to load as plugins", false,
    "foobar.so", "foobar.so", cmd);
 
static TCLAP::ValueArg<double> argAutoPlayPeriod(
    "", "autoplay-period",
    "The period (in seconds) between timestamps to load and show in autoplay "
    "mode.",
    false, 0.1, "period [seconds]", cmd);
 
// =========== Declare global variables ===========
#if MRPT_HAS_NANOGUI
 
auto                              glVizICP = mrpt::opengl::CSetOfObjects::Create();
mrpt::gui::CDisplayWindowGUI::Ptr win;
 
nanogui::Slider* slSelectorICP   = nullptr;
nanogui::Button *btnSelectorBack = nullptr, *btnSelectorForw = nullptr;
nanogui::Button* btnSelectorAutoplay = nullptr;
bool             isAutoPlayActive    = false;
double           lastAutoPlayTime    = .0;
 
std::array<nanogui::TextBox*, 5> lbICPStats         = {nullptr, nullptr, nullptr, nullptr, nullptr};
nanogui::CheckBox*               cbShowInitialPose  = nullptr;
nanogui::Label*                  lbICPIteration     = nullptr;
nanogui::Slider*                 slIterationDetails = nullptr;
 
const size_t                   MAX_VARIABLE_LIST = 100;
std::vector<nanogui::TextBox*> lbDynVariables;
 
nanogui::CheckBox* cbViewOrtho           = nullptr;
nanogui::CheckBox* cbCameraFollowsLocal  = nullptr;
nanogui::CheckBox* cbViewVoxelsAsPoints  = nullptr;
nanogui::CheckBox* cbViewVoxelsFreeSpace = nullptr;
nanogui::CheckBox* cbColorizeLocalMap    = nullptr;
nanogui::CheckBox* cbColorizeGlobalMap   = nullptr;
 
nanogui::CheckBox* cbViewPairings = nullptr;
 
nanogui::CheckBox* cbViewPairings_pt2pt = nullptr;
nanogui::CheckBox* cbViewPairings_pt2pl = nullptr;
nanogui::CheckBox* cbViewPairings_pt2ln = nullptr;
 
nanogui::TextBox *tbLogPose = nullptr, *tbInitialGuess = nullptr, *tbInit2Final = nullptr,
                 *tbCovariance = nullptr, *tbConditionNumber = nullptr, *tbPairings = nullptr;
 
nanogui::Slider* slPairingsPl2PlSize   = nullptr;
nanogui::Slider* slPairingsPl2LnSize   = nullptr;
nanogui::Slider* slGlobalPointSize     = nullptr;
nanogui::Slider* slLocalPointSize      = nullptr;
nanogui::Slider* slMidDepthField       = nullptr;
nanogui::Slider* slThicknessDepthField = nullptr;
nanogui::Label * lbDepthFieldValues = nullptr, *lbDepthFieldMid = nullptr,
               *lbDepthFieldThickness = nullptr;
 
nanogui::Slider* slGTPose[6] = {nullptr, nullptr, nullptr, nullptr, nullptr, nullptr};
 
std::vector<std::string> layerNames_global, layerNames_local;
 
std::map<std::string, nanogui::CheckBox*> cbLayersByName_global;
std::map<std::string, nanogui::CheckBox*> cbLayersByName_local;
 
class DelayedLoadLog
{
   public:
    DelayedLoadLog() = default;
    DelayedLoadLog(const std::string& fileName, const std::string& shortFileName)
        : filename_(fileName), shortFileName_(shortFileName)
    {
    }
 
    mp2p_icp::LogRecord& get()
    {
        if (!log_)
        {
            // Load now:
            log_ = mp2p_icp::LogRecord::LoadFromFile(filename_);
        }
 
        return log_.value();
    }
 
    void dispose() { log_.reset(); }
 
    const std::string& filename() const { return filename_; }
    const std::string& shortFileName() const { return shortFileName_; }
 
   private:
    std::optional<mp2p_icp::LogRecord> log_;
    std::string                        filename_, shortFileName_;
};
 
std::vector<DelayedLoadLog> logRecords;
 
static void rebuild_3d_view(bool regenerateMaps = true);
 
namespace
{
void rebuild_3d_view_fast() { rebuild_3d_view(false); }
 
void processAutoPlay()
{
    if (!isAutoPlayActive) return;
 
    const double tNow = mrpt::Clock::nowDouble();
    if (tNow - lastAutoPlayTime < argAutoPlayPeriod.getValue()) return;
 
    lastAutoPlayTime = tNow;
 
    if (slSelectorICP->value() < slSelectorICP->range().second - 0.01f)
    {
        slSelectorICP->setValue(slSelectorICP->value() + 1);
        rebuild_3d_view();
    }
}
 
void updateMiniCornerView()
{
    auto gl_view = win->background_scene->getViewport("small-view");
    if (!gl_view) return;
 
    mrpt::opengl::CCamera& view_cam = gl_view->getCamera();
 
    view_cam.setAzimuthDegrees(win->camera().getAzimuthDegrees());
    view_cam.setElevationDegrees(win->camera().getElevationDegrees());
    view_cam.setZoomDistance(5);
}
 
void main_show_gui()
{
    using namespace std::string_literals;
 
    mrpt::system::CDirectoryExplorer::TFileInfoList files;
 
    if (!argSingleFile.isSet())
    {
        const std::string searchDir = argSearchDir.getValue();
        ASSERT_DIRECTORY_EXISTS_(searchDir);
 
        std::cout << "Searching in: '" << searchDir << "' for files with extension '"
                  << argExtension.getValue() << "'" << std::endl;
 
        mrpt::system::CDirectoryExplorer::explore(searchDir, FILE_ATTRIB_ARCHIVE, files);
        mrpt::system::CDirectoryExplorer::filterByExtension(files, argExtension.getValue());
        mrpt::system::CDirectoryExplorer::sortByName(files);
 
        std::cout << "Found " << files.size() << " ICP records." << std::endl;
    }
    else
    {
        // Load one single file:
        std::cout << "Loading one single log file: " << argSingleFile.getValue() << std::endl;
 
        files.resize(1);
        files[0].wholePath = argSingleFile.getValue();
    }
 
    // load files:
    for (const auto& file : files) logRecords.emplace_back(file.wholePath, file.name);
 
    ASSERT_(!logRecords.empty());
 
    // Obtain layer info from first entry:
    {
        const auto& lr = logRecords.front().get();
        if (layerNames_global.empty() && lr.pcGlobal)
        {
            for (const auto& layer : lr.pcGlobal->layers)
            {
                layerNames_global.push_back(layer.first);
                std::cout << "Global point cloud: Found point layer='" << layer.first << "'\n";
            }
        }
        if (layerNames_local.empty() && lr.pcLocal)
        {
            for (const auto& layer : lr.pcLocal->layers)
            {
                layerNames_local.push_back(layer.first);
                std::cout << "Local point cloud: Found point layer='" << layer.first << "'\n";
            }
        }
    }
 
    // Get user app config file
    char appCfgFile[1024];
    ::get_user_config_file(appCfgFile, sizeof(appCfgFile), APP_NAME);
    mrpt::config::CConfigFile appCfg(appCfgFile);
 
    /*
     * -------------------------------------------------------------------
     * GUI
     * --------------------------------------------------------------------
     */
    nanogui::init();
 
    mrpt::gui::CDisplayWindowGUI_Params cp;
    cp.maximized = true;
    win          = mrpt::gui::CDisplayWindowGUI::Create(APP_NAME, 1024, 800, cp);
 
    // Add a background scene:
    auto scene = mrpt::opengl::COpenGLScene::Create();
    {
        auto glGrid = mrpt::opengl::CGridPlaneXY::Create();
        glGrid->setColor_u8(0xff, 0xff, 0xff, 0x10);
        scene->insert(glGrid);
    }
 
    auto gl_base = mrpt::opengl::stock_objects::CornerXYZ(1.0f);
    gl_base->setName("Global");
    gl_base->enableShowName();
    scene->insert(gl_base);
 
    scene->insert(glVizICP);
 
    {
        std::lock_guard<std::mutex> lck(win->background_scene_mtx);
        win->background_scene = std::move(scene);
    }
 
    // Control GUI sub-window:
    auto w = win->createManagedSubWindow("Control");
    w->setPosition({5, 25});
    w->requestFocus();
    w->setLayout(
        new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill, 5, 2));
    w->setFixedWidth(WINDOW_FIXED_WIDTH);
 
    cbShowInitialPose = w->add<nanogui::CheckBox>("Show at INITIAL GUESS pose");
    cbShowInitialPose->setCallback(
        [=](bool v)
        {
            if (slIterationDetails->enabled())
            {
                const auto& r = slIterationDetails->range();
                slIterationDetails->setValue(v ? r.first : r.second);
            }
            rebuild_3d_view_fast();
        });
    lbICPIteration     = w->add<nanogui::Label>("Show ICP iteration:");
    slIterationDetails = w->add<nanogui::Slider>();
    slIterationDetails->setRange({.0f, 1.0f});
    slIterationDetails->setCallback([](float) { rebuild_3d_view_fast(); });
 
    //
    w->add<nanogui::Label>(" ");  // separator
    w->add<nanogui::Label>(mrpt::format(
        "Select ICP record file (N=%u)", static_cast<unsigned int>(logRecords.size())));
    slSelectorICP = w->add<nanogui::Slider>();
    slSelectorICP->setRange({.0f, logRecords.size() - 1});
    slSelectorICP->setValue(0);
    slSelectorICP->setCallback([&](float /*v*/) { rebuild_3d_view(); });
 
    for (auto& lb : lbICPStats)
    {
        lb = w->add<nanogui::TextBox>("  ");
        lb->setFontSize(MID_FONT_SIZE);
        lb->setAlignment(nanogui::TextBox::Alignment::Left);
        lb->setEditable(true);
    }
 
    // navigation panel:
    {
        auto pn = w->add<nanogui::Widget>();
        pn->setLayout(new nanogui::BoxLayout(nanogui::Orientation::Horizontal));
 
        // shortcut:
        auto s = slSelectorICP;
 
        btnSelectorBack = pn->add<nanogui::Button>("", ENTYPO_ICON_CONTROLLER_FAST_BACKWARD);
        btnSelectorBack->setCallback(
            [=]()
            {
                if (s->value() > 0)
                {
                    s->setValue(s->value() - 1);
                    s->callback()(s->value());
                }
            });
 
        btnSelectorForw = pn->add<nanogui::Button>("", ENTYPO_ICON_CONTROLLER_FAST_FORWARD);
        btnSelectorForw->setCallback(
            [=]()
            {
                if (s->value() < s->range().second - 0.01f)
                {
                    s->setValue(s->value() + 1);
                    rebuild_3d_view();
                }
            });
 
        pn->add<nanogui::Label>(" ");  // separator
 
        btnSelectorAutoplay = pn->add<nanogui::Button>("", ENTYPO_ICON_CONTROLLER_PLAY);
        btnSelectorAutoplay->setFlags(nanogui::Button::ToggleButton);
 
        btnSelectorAutoplay->setChangeCallback([&](bool active) { isAutoPlayActive = active; });
    }
 
    //
    w->add<nanogui::Label>(" ");  // separator
 
    auto tabWidget = w->add<nanogui::TabWidget>();
 
    auto* tab1 = tabWidget->createTab("Summary");
    tab1->setLayout(
        new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill));
 
    auto* tab2 = tabWidget->createTab("Variables");
    tab2->setLayout(
        new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill));
 
    auto* tab3 = tabWidget->createTab("Maps");
    tab3->setLayout(new nanogui::GroupLayout());
 
    auto* tab4 = tabWidget->createTab("Pairings");
    tab4->setLayout(new nanogui::GroupLayout());
 
    auto* tab5 = tabWidget->createTab("View");
    tab5->setLayout(new nanogui::GroupLayout());
 
    auto* tab6 = tabWidget->createTab("Manual");
    tab6->setLayout(new nanogui::GroupLayout());
 
    tabWidget->setActiveTab(0);
 
    tab1->add<nanogui::Label>(" ")->setFontSize(SMALL_FONT_SIZE);
    tab1->add<nanogui::Label>("ICP result pose [x y z yaw(deg) pitch(deg) roll(deg)]:")
        ->setFontSize(MID_FONT_SIZE);
    tbLogPose = tab1->add<nanogui::TextBox>();
    tbLogPose->setFontSize(MID_FONT_SIZE);
    tbLogPose->setEditable(true);
    tbLogPose->setAlignment(nanogui::TextBox::Alignment::Left);
    tab1->add<nanogui::Label>(" ")->setFontSize(SMALL_FONT_SIZE);
 
    tab1->add<nanogui::Label>("Initial -> final pose change:")->setFontSize(MID_FONT_SIZE);
    tbInit2Final = tab1->add<nanogui::TextBox>();
    tbInit2Final->setFontSize(MID_FONT_SIZE);
    tbInit2Final->setEditable(false);
    tab1->add<nanogui::Label>(" ")->setFontSize(SMALL_FONT_SIZE);
 
    tab1->add<nanogui::Label>("Uncertainty: diagonal sigmas (x y z yaw pitch roll)")
        ->setFontSize(MID_FONT_SIZE);
    tbCovariance = tab1->add<nanogui::TextBox>();
    tbCovariance->setFontSize(MID_FONT_SIZE);
    tbCovariance->setEditable(false);
    tab1->add<nanogui::Label>(" ")->setFontSize(SMALL_FONT_SIZE);
 
    tab1->add<nanogui::Label>("Uncertainty: Covariance condition numbers")
        ->setFontSize(MID_FONT_SIZE);
    tbConditionNumber = tab1->add<nanogui::TextBox>();
    tbConditionNumber->setFontSize(MID_FONT_SIZE);
    tbConditionNumber->setEditable(false);
    tab1->add<nanogui::Label>(" ");
 
    tab6->add<nanogui::Label>("Manual solution modification:");
    const float handTunedRange[6] = {4.0, 4.0, 10.0, 0.5 * M_PI, 0.25 * M_PI, 0.5};
 
    for (int i = 0; i < 6; i++)
    {
        slGTPose[i] = tab6->add<nanogui::Slider>();
        slGTPose[i]->setRange({-handTunedRange[i], handTunedRange[i]});
        slGTPose[i]->setValue(0.0f);
 
        slGTPose[i]->setCallback(
            [=](float v)
            {
                const size_t idx = mrpt::round(slSelectorICP->value());
                auto&        lr  = logRecords.at(idx).get();
 
                auto p                       = lr.icpResult.optimal_tf.mean.asTPose();
                p[i]                         = v;
                lr.icpResult.optimal_tf.mean = mrpt::poses::CPose3D(p);
 
                rebuild_3d_view_fast();
            });
    }
 
    tab1->add<nanogui::Label>("Initial guess pose:");
    tbInitialGuess = tab1->add<nanogui::TextBox>();
    tbInitialGuess->setFontSize(14);
    tbInitialGuess->setEditable(true);
    tbInitialGuess->setAlignment(nanogui::TextBox::Alignment::Left);
 
    // Save map buttons:
    auto lambdaSave = [&](const mp2p_icp::metric_map_t& m)
    {
        const std::string outFile = nanogui::file_dialog(
            {{"mm", "mp2p_icp::metric_map_t binary serialized object (*.mm)"}}, true /*save*/);
        if (outFile.empty()) return;
        m.save_to_file(outFile);
    };
 
    // tab 2: variables
    {
        tab2->add<nanogui::Label>("Dynamic variables:");
 
        auto vscroll = tab2->add<nanogui::VScrollPanel>();
        vscroll->setFixedSize({WINDOW_FIXED_WIDTH - 15, 300});
 
        auto wrapper = vscroll->add<nanogui::Widget>();
 
        wrapper->setFixedSize({WINDOW_FIXED_WIDTH - 30, 300});
        wrapper->setLayout(
            new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill));
 
        for (size_t i = 0; i < MAX_VARIABLE_LIST; i++)
        {
            auto* tb = wrapper->add<nanogui::TextBox>("aaaa");
            tb->setAlignment(nanogui::TextBox::Alignment::Left);
            tb->setEditable(true);
            tb->setFontSize(MID_FONT_SIZE);
            lbDynVariables.push_back(tb);
        }
    }
 
    // tab 3: maps
    {
        auto pn = tab3->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Fill));
        pn->add<nanogui::Button>("Export 'local' map...")
            ->setCallback(
                [&]()
                {
                    const size_t idx = mrpt::round(slSelectorICP->value());
                    auto&        lr  = logRecords.at(idx).get();
                    ASSERT_(lr.pcLocal);
                    lambdaSave(*lr.pcLocal);
                });
        pn->add<nanogui::Button>("Export 'global' map...")
            ->setCallback(
                [&]()
                {
                    const size_t idx = mrpt::round(slSelectorICP->value());
                    auto&        lr  = logRecords.at(idx).get();
                    ASSERT_(lr.pcGlobal);
                    lambdaSave(*lr.pcGlobal);
                });
    }
 
    tab3->add<nanogui::Label>("[GLOBAL map] Visible layers:");
 
    for (size_t i = 0; i < layerNames_global.size(); i++)
    {
        auto cb = tab3->add<nanogui::CheckBox>(layerNames_global.at(i));
        cb->setChecked(true);
        cb->setCallback([](bool) { rebuild_3d_view(); });
        cb->setFontSize(13);
 
        cbLayersByName_global[layerNames_global.at(i)] = cb;
    }
 
    tab3->add<nanogui::Label>("[LOCAL map] Visible layers:");
    for (size_t i = 0; i < layerNames_local.size(); i++)
    {
        auto cb = tab3->add<nanogui::CheckBox>(layerNames_local.at(i));
        cb->setChecked(true);
        cb->setCallback([](bool) { rebuild_3d_view(); });
        cb->setFontSize(13);
 
        cbLayersByName_local[layerNames_local.at(i)] = cb;
    }
 
    // tab4: pairings:
    tbPairings = tab4->add<nanogui::TextBox>();
    tbPairings->setFontSize(16);
    tbPairings->setEditable(false);
 
    cbViewPairings = tab4->add<nanogui::CheckBox>("View pairings");
    cbViewPairings->setCallback([](bool) { rebuild_3d_view_fast(); });
 
    cbViewPairings_pt2pt = tab4->add<nanogui::CheckBox>("View: point-to-point");
    cbViewPairings_pt2pt->setChecked(true);
    cbViewPairings_pt2pt->setCallback([](bool) { rebuild_3d_view_fast(); });
 
    {
        auto pn = tab4->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill));
 
        cbViewPairings_pt2pl = pn->add<nanogui::CheckBox>("View: point-to-plane");
        cbViewPairings_pt2pl->setChecked(true);
        cbViewPairings_pt2pl->setCallback([](bool) { rebuild_3d_view_fast(); });
 
        pn->add<nanogui::Label>("Plane size:");
        slPairingsPl2PlSize = pn->add<nanogui::Slider>();
        slPairingsPl2PlSize->setRange({-2.0f, 2.0f});
        slPairingsPl2PlSize->setValue(-1.0f);
        slPairingsPl2PlSize->setCallback([&](float) { rebuild_3d_view_fast(); });
    }
 
    {
        auto pn = tab4->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill));
 
        cbViewPairings_pt2ln = pn->add<nanogui::CheckBox>("View: point-to-line");
        cbViewPairings_pt2ln->setChecked(true);
        cbViewPairings_pt2ln->setCallback([](bool) { rebuild_3d_view_fast(); });
 
        pn->add<nanogui::Label>("Line length:");
        slPairingsPl2LnSize = pn->add<nanogui::Slider>();
        slPairingsPl2LnSize->setRange({-2.0f, 2.0f});
        slPairingsPl2LnSize->setValue(-1.0f);
        slPairingsPl2LnSize->setCallback([&](float) { rebuild_3d_view_fast(); });
    }
 
    // tab5: view
    {
        auto pn = tab5->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill));
 
        pn->add<nanogui::Label>("Global map point size");
 
        slGlobalPointSize = pn->add<nanogui::Slider>();
        slGlobalPointSize->setRange({1.0f, 10.0f});
        slGlobalPointSize->setValue(2.0f);
        slGlobalPointSize->setCallback([&](float) { rebuild_3d_view(); });
    }
    {
        auto pn = tab5->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill));
 
        pn->add<nanogui::Label>("Local map point size");
 
        slLocalPointSize = pn->add<nanogui::Slider>();
        slLocalPointSize->setRange({1.0f, 10.0f});
        slLocalPointSize->setValue(2.0f);
        slLocalPointSize->setCallback([&](float) { rebuild_3d_view(); });
    }
    {
        auto pn = tab5->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill));
 
        lbDepthFieldMid = pn->add<nanogui::Label>("Center depth clip plane:");
        slMidDepthField = pn->add<nanogui::Slider>();
    }
    slMidDepthField->setRange({-2.0, 3.0});
    slMidDepthField->setValue(1.0f);
    slMidDepthField->setCallback([&](float) { rebuild_3d_view_fast(); });
 
    {
        auto pn = tab5->add<nanogui::Widget>();
        pn->setLayout(
            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill));
 
        lbDepthFieldThickness = pn->add<nanogui::Label>("Max-Min depth thickness:");
        slThicknessDepthField = pn->add<nanogui::Slider>();
    }
    slThicknessDepthField->setRange({-2.0, 6.0});
    slThicknessDepthField->setValue(3.0);
    slThicknessDepthField->setCallback([&](float) { rebuild_3d_view_fast(); });
    lbDepthFieldValues = tab5->add<nanogui::Label>(" ");
 
    cbViewOrtho = tab5->add<nanogui::CheckBox>("Orthogonal view");
    cbViewOrtho->setCallback([&](bool) { rebuild_3d_view_fast(); });
 
    cbCameraFollowsLocal = tab5->add<nanogui::CheckBox>("Camera follows 'local'");
    cbCameraFollowsLocal->setCallback([&](bool) { rebuild_3d_view_fast(); });
 
    cbViewVoxelsAsPoints = tab5->add<nanogui::CheckBox>("Render voxel maps as point clouds");
    cbViewVoxelsAsPoints->setChecked(true);
    cbViewVoxelsAsPoints->setCallback([&](bool) { rebuild_3d_view(); });
 
    cbViewVoxelsFreeSpace = tab5->add<nanogui::CheckBox>("Render free space of voxel maps");
    cbViewVoxelsFreeSpace->setChecked(false);
    cbViewVoxelsFreeSpace->setCallback([&](bool) { rebuild_3d_view(); });
 
    cbColorizeLocalMap = tab5->add<nanogui::CheckBox>("Recolorize local map");
    cbColorizeLocalMap->setCallback([&](bool) { rebuild_3d_view(); });
 
    cbColorizeGlobalMap = tab5->add<nanogui::CheckBox>("Recolorize global map");
    cbColorizeGlobalMap->setCallback([&](bool) { rebuild_3d_view(); });
 
    // ----
    w->add<nanogui::Label>(" ");  // separator
    w->add<nanogui::Button>("Quit", ENTYPO_ICON_ARROW_BOLD_LEFT)
        ->setCallback([]() { win->setVisible(false); });
 
    win->setKeyboardCallback(
        [&](int key, [[maybe_unused]] int scancode, int action, [[maybe_unused]] int modifiers)
        {
            if (action != GLFW_PRESS && action != GLFW_REPEAT) return false;
 
            int increment = 0;
            switch (key)
            {
                case GLFW_KEY_LEFT:
                    increment = -1;
                    break;
                case GLFW_KEY_RIGHT:
                    increment = +1;
                    break;
                case GLFW_KEY_PAGE_DOWN:
                    increment = +100;
                    break;
                case GLFW_KEY_PAGE_UP:
                    increment = -100;
                    break;
                case GLFW_KEY_SPACE:
                    isAutoPlayActive = !isAutoPlayActive;
                    btnSelectorAutoplay->setPushed(isAutoPlayActive);
                    break;
                case 'i':
                case 'I':
                    cbShowInitialPose->setChecked(!cbShowInitialPose->checked());
                    cbShowInitialPose->callback()(cbShowInitialPose->checked());
                    break;
            };
 
            if (increment != 0)
            {
                nanogui::Slider* sl = slSelectorICP;  // shortcut
                sl->setValue(sl->value() + increment);
                if (sl->value() < 0) sl->setValue(0);
                if (sl->value() > sl->range().second) sl->setValue(sl->range().second);
                rebuild_3d_view();
            }
 
            return false;
        });
 
    win->performLayout();
    win->camera().setCameraPointing(8.0f, .0f, .0f);
    win->camera().setAzimuthDegrees(110.0f);
    win->camera().setElevationDegrees(15.0f);
    win->camera().setZoomDistance(30.0f);
 
    // save and load UI state:
#define LOAD_CB_STATE(CB_NAME__) do_cb(CB_NAME__, #CB_NAME__)
#define SAVE_CB_STATE(CB_NAME__) appCfg.write("", #CB_NAME__, CB_NAME__->checked())
 
#define LOAD_SL_STATE(SL_NAME__) do_sl(SL_NAME__, #SL_NAME__)
#define SAVE_SL_STATE(SL_NAME__) appCfg.write("", #SL_NAME__, SL_NAME__->value())
 
    auto load_UI_state_from_user_config = [&]()
    {
        auto do_cb = [&](nanogui::CheckBox* cb, const std::string& name)
        { cb->setChecked(appCfg.read_bool("", name, cb->checked())); };
        auto do_sl = [&](nanogui::Slider* sl, const std::string& name)
        { sl->setValue(appCfg.read_float("", name, sl->value())); };
 
        LOAD_CB_STATE(cbColorizeLocalMap);
        LOAD_CB_STATE(cbColorizeGlobalMap);
        LOAD_CB_STATE(cbShowInitialPose);
        LOAD_CB_STATE(cbViewOrtho);
        LOAD_CB_STATE(cbCameraFollowsLocal);
        LOAD_CB_STATE(cbViewVoxelsAsPoints);
        LOAD_CB_STATE(cbViewPairings);
        LOAD_CB_STATE(cbViewPairings_pt2pt);
        LOAD_CB_STATE(cbViewPairings_pt2pl);
        LOAD_CB_STATE(cbViewPairings_pt2ln);
 
        LOAD_SL_STATE(slPairingsPl2PlSize);
        LOAD_SL_STATE(slPairingsPl2LnSize);
        LOAD_SL_STATE(slGlobalPointSize);
        LOAD_SL_STATE(slLocalPointSize);
        LOAD_SL_STATE(slMidDepthField);
        LOAD_SL_STATE(slThicknessDepthField);
 
        win->camera().setCameraPointing(
            appCfg.read_float("", "cam_x", win->camera().getCameraPointingX()),
            appCfg.read_float("", "cam_y", win->camera().getCameraPointingY()),
            appCfg.read_float("", "cam_z", win->camera().getCameraPointingZ()));
        win->camera().setAzimuthDegrees(
            appCfg.read_float("", "cam_az", win->camera().getAzimuthDegrees()));
        win->camera().setElevationDegrees(
            appCfg.read_float("", "cam_el", win->camera().getElevationDegrees()));
        win->camera().setZoomDistance(
            appCfg.read_float("", "cam_d", win->camera().getZoomDistance()));
    };
    auto save_UI_state_to_user_config = [&]()
    {
        SAVE_CB_STATE(cbColorizeLocalMap);
        SAVE_CB_STATE(cbColorizeGlobalMap);
        SAVE_CB_STATE(cbShowInitialPose);
        SAVE_CB_STATE(cbViewOrtho);
        SAVE_CB_STATE(cbCameraFollowsLocal);
        SAVE_CB_STATE(cbViewVoxelsAsPoints);
        SAVE_CB_STATE(cbViewPairings);
        SAVE_CB_STATE(cbViewPairings_pt2pt);
        SAVE_CB_STATE(cbViewPairings_pt2pl);
        SAVE_CB_STATE(cbViewPairings_pt2ln);
 
        SAVE_SL_STATE(slPairingsPl2PlSize);
        SAVE_SL_STATE(slPairingsPl2LnSize);
        SAVE_SL_STATE(slGlobalPointSize);
        SAVE_SL_STATE(slLocalPointSize);
        SAVE_SL_STATE(slMidDepthField);
        SAVE_SL_STATE(slThicknessDepthField);
 
        appCfg.write("", "cam_x", win->camera().getCameraPointingX());
        appCfg.write("", "cam_y", win->camera().getCameraPointingY());
        appCfg.write("", "cam_z", win->camera().getCameraPointingZ());
        appCfg.write("", "cam_az", win->camera().getAzimuthDegrees());
        appCfg.write("", "cam_el", win->camera().getElevationDegrees());
        appCfg.write("", "cam_d", win->camera().getZoomDistance());
    };
 
    // load UI state from last session:
    load_UI_state_from_user_config();
 
    rebuild_3d_view();
 
    // Main loop
    // ---------------------
    win->drawAll();
    win->setVisible(true);
 
    win->addLoopCallback(
        [&]()
        {
            processAutoPlay();
            updateMiniCornerView();
        });
 
    nanogui::mainloop(1000 /*idleLoopPeriod ms*/, 25 /* minRepaintPeriod ms */);
 
    nanogui::shutdown();
 
    // save UI state:
    save_UI_state_to_user_config();
}
 
}  // namespace
 
template <class MATRIX>  //
double conditionNumber(const MATRIX& m)
{
    MATRIX              eVecs;
    std::vector<double> eVals;
    m.eig_symmetric(eVecs, eVals);
    return eVals.back() / eVals.front();
}
 
// ==============================
// rebuild_3d_view
// ==============================
void rebuild_3d_view(bool regenerateMaps)
{
    using namespace std::string_literals;
 
    const size_t idx = mrpt::round(slSelectorICP->value());
 
    btnSelectorBack->setEnabled(!logRecords.empty() && idx > 0);
    btnSelectorForw->setEnabled(!logRecords.empty() && idx < logRecords.size() - 1);
 
    if (idx >= logRecords.size()) return;
 
    glVizICP->clear();
 
    // Free memory
    static std::optional<size_t> lastIdx;
    bool                         mustResetIterationSlider = false;
 
    if (!lastIdx || (lastIdx && idx != *lastIdx))
    {
        // free memory:
        if (lastIdx) logRecords.at(*lastIdx).dispose();
 
        // and note that we should show the first/last ICP iteration:
        mustResetIterationSlider = true;
    }
    lastIdx = idx;
 
    // lazy load from disk happens in the "get()":
    const auto& lr = logRecords.at(idx).get();
 
    lbICPStats[0]->setValue(logRecords.at(idx).shortFileName());
 
    lbICPStats[1]->setValue(mrpt::format(
        "ICP log #%zu | Local: ID:%u%s | Global: ID:%u%s", idx,
        static_cast<unsigned int>(lr.pcLocal->id ? lr.pcLocal->id.value() : 0),
        lr.pcLocal->label ? lr.pcLocal->label.value().c_str() : "",
        static_cast<unsigned int>(lr.pcGlobal->id ? lr.pcGlobal->id.value() : 0),
        lr.pcGlobal->label ? lr.pcGlobal->label.value().c_str() : ""));
 
    lbICPStats[2]->setValue(mrpt::format(
        "Quality: %.02f%% | Iters: %u | Term.Reason: %s", 100.0 * lr.icpResult.quality,
        static_cast<unsigned int>(lr.icpResult.nIterations),
        mrpt::typemeta::enum2str(lr.icpResult.terminationReason).c_str()));
 
    lbICPStats[3]->setValue("Global: "s + lr.pcGlobal->contents_summary());
    lbICPStats[4]->setValue("Local: "s + lr.pcLocal->contents_summary());
 
    tbInitialGuess->setValue(lr.initialGuessLocalWrtGlobal.asString());
 
    tbLogPose->setValue(lr.icpResult.optimal_tf.mean.asString());
 
    // dyn variables:
    {
        for (auto* lb : lbDynVariables) lb->setValue("");
 
        size_t lbIdx = 0;
        for (const auto& [name, value] : lr.dynamicVariables)
        {
            lbDynVariables[lbIdx++]->setValue(mrpt::format("%s = %g", name.c_str(), value));
            if (lbIdx >= MAX_VARIABLE_LIST) break;
        }
    }
 
    {
        const auto poseChange =
            lr.icpResult.optimal_tf.mean - mrpt::poses::CPose3D(lr.initialGuessLocalWrtGlobal);
 
        tbInit2Final->setValue(mrpt::format(
            "|T|=%.03f [m]  |R|=%.03f [deg]", poseChange.norm(),
            mrpt::RAD2DEG(mrpt::poses::Lie::SO<3>::log(poseChange.getRotationMatrix()).norm())));
    }
 
    const auto                      poseFromCorner = mrpt::poses::CPose3D::Identity();
    mrpt::poses::CPose3DPDFGaussian relativePose;
    const mp2p_icp::Pairings*       pairsToViz = nullptr;
 
    if (!lr.iterationsDetails.has_value() || lr.iterationsDetails->empty())
    {
        slIterationDetails->setEnabled(false);
 
        if (cbShowInitialPose->checked())
        {
            relativePose.mean = mrpt::poses::CPose3D(lr.initialGuessLocalWrtGlobal);
            lbICPIteration->setCaption("Show ICP iteration: INITIAL");
        }
        else
        {
            relativePose = lr.icpResult.optimal_tf;
            lbICPIteration->setCaption("Show ICP iteration: FINAL");
        }
 
        if (cbViewPairings->checked()) pairsToViz = &lr.icpResult.finalPairings;
    }
    else
    {
        slIterationDetails->setEnabled(true);
        slIterationDetails->setRange({.0f, static_cast<float>(lr.iterationsDetails->size() - 1)});
 
        if (mustResetIterationSlider)
            slIterationDetails->setValue(
                cbShowInitialPose->checked() ? slIterationDetails->range().first
                                             : slIterationDetails->range().second);
 
        // final or partial solution?
        auto it = lr.iterationsDetails->begin();
 
        size_t nIter = mrpt::round(slIterationDetails->value());
        mrpt::keep_min(nIter, lr.iterationsDetails->size() - 1);
 
        std::advance(it, nIter);
 
        relativePose.mean = it->second.optimalPose;
        if (cbViewPairings->checked()) pairsToViz = &it->second.pairings;
 
        lbICPIteration->setCaption(
            "Show ICP iteration: "s + std::to_string(it->first) + "/"s +
            std::to_string(lr.iterationsDetails->rbegin()->first));
    }
 
    {
        std::string s;
        for (int i = 0; i < 6; i++) s += mrpt::format("%.02f ", std::sqrt(relativePose.cov(i, i)));
 
        s += mrpt::format(
            " det(XYZ)=%.02e det(rot)=%.02e", relativePose.cov.blockCopy<3, 3>(0, 0).det(),
            relativePose.cov.blockCopy<3, 3>(3, 3).det());
 
        tbCovariance->setValue(s);
    }
 
    // Extract SE(2) covariance:
    const mrpt::poses::CPosePDFGaussian pose2D(relativePose);
 
    // Condition numbers:
    tbConditionNumber->setValue(mrpt::format(
        " cn{XYZ}=%.02f cn{SO(3)}=%.02f cn{SE(2)}=%.02f "
        "cn{SE(3)}=%.02f",
        conditionNumber(relativePose.cov.blockCopy<3, 3>(0, 0)),
        conditionNumber(relativePose.cov.blockCopy<3, 3>(3, 3)), conditionNumber(pose2D.cov),
        conditionNumber(relativePose.cov)));
 
    // 3D objects -------------------
    auto glCornerFrom = mrpt::opengl::stock_objects::CornerXYZSimple(0.75f, 3.0f);
    glCornerFrom->setPose(poseFromCorner);
    glVizICP->insert(glCornerFrom);
 
    auto glCornerLocal = mrpt::opengl::stock_objects::CornerXYZSimple(0.85f, 5.0f);
    glCornerLocal->setPose(relativePose.mean);
    glCornerLocal->setName("Local");
    glCornerLocal->enableShowName(true);
    glVizICP->insert(glCornerLocal);
 
    auto glCornerToCov = mrpt::opengl::CEllipsoid3D::Create();
    glCornerToCov->set3DsegmentsCount(16);
    glCornerToCov->enableDrawSolid3D(true);
    glCornerToCov->setColor_u8(0xff, 0x00, 0x00, 0x40);
    //  std::cout << "cov:\n" << relativePose.cov << "\n";
    glCornerToCov->setCovMatrixAndMean(
        relativePose.cov.blockCopy<3, 3>(0, 0), relativePose.mean.asVectorVal().head<3>());
    glVizICP->insert(glCornerToCov);
 
    // GLOBAL PC:
    mp2p_icp::render_params_t rpGlobal;
 
    rpGlobal.points.visible = false;
    for (const auto& [lyName, cb] : cbLayersByName_global)
    {
        // Update stats in the cb label:
        cb->setCaption(lyName);  // default
        if (auto itL = lr.pcGlobal->layers.find(lyName); itL != lr.pcGlobal->layers.end())
        {
            if (auto pc = std::dynamic_pointer_cast<mrpt::maps::CPointsMap>(itL->second); pc)
            {
                cb->setCaption(
                    lyName + " | "s + mrpt::system::unitsFormat(static_cast<double>(pc->size())) +
                    " points"s + " | class="s + pc->GetRuntimeClass()->className);
            }
            else
            {
                cb->setCaption(lyName + " | class="s + itL->second->GetRuntimeClass()->className);
            }
        }
 
        // show/hide:
        if (!cb->checked()) continue;  // hidden
        rpGlobal.points.visible = true;
 
        auto& rpL                       = rpGlobal.points.perLayer[lyName];
        rpL.pointSize                   = slGlobalPointSize->value();
        rpL.render_voxelmaps_as_points  = cbViewVoxelsAsPoints->checked();
        rpL.render_voxelmaps_free_space = cbViewVoxelsFreeSpace->checked();
 
        if (cbColorizeGlobalMap->checked())
        {
            auto& cm                  = rpL.colorMode.emplace();
            cm.colorMap               = mrpt::img::TColormap::cmHOT;
            cm.recolorizeByCoordinate = mp2p_icp::Coordinate::Z;
        }
    }
 
    static mrpt::opengl::CSetOfObjects::Ptr lastGlobalPts;
 
    if (!lastGlobalPts || regenerateMaps)
    {
        // Show all or selected layers:
        for (auto& rpL : rpGlobal.points.perLayer)
            rpL.second.color = mrpt::img::TColor(0xff, 0x00, 0x00, 0xff);
 
        auto glPts    = lr.pcGlobal->get_visualization(rpGlobal);
        lastGlobalPts = glPts;
 
        // Show all or selected layers:
        rpGlobal.points.allLayers.color = mrpt::img::TColor(0xff, 0x00, 0x00, 0xff);
 
        glVizICP->insert(glPts);
    }
    else
    {
        // avoid the costly method of re-rendering maps, if possible:
        glVizICP->insert(lastGlobalPts);
    }
 
    // LOCAL PC:
    mp2p_icp::render_params_t rpLocal;
 
    rpLocal.points.visible = false;
    for (const auto& [lyName, cb] : cbLayersByName_local)
    {
        // Update stats in the cb label:
        cb->setCaption(lyName);  // default
        if (auto itL = lr.pcLocal->layers.find(lyName); itL != lr.pcLocal->layers.end())
        {
            if (auto pc = std::dynamic_pointer_cast<mrpt::maps::CPointsMap>(itL->second); pc)
            {
                cb->setCaption(
                    lyName + " | "s +
                    mrpt::system::unitsFormat(static_cast<double>(pc->size()), 2, false) +
                    " points"s + " | class="s + pc->GetRuntimeClass()->className);
            }
            else
            {
                cb->setCaption(lyName + " | class="s + itL->second->GetRuntimeClass()->className);
            }
        }
 
        // show/hide:
        if (!cb->checked()) continue;  // hidden
        rpLocal.points.visible = true;
 
        auto& rpL                       = rpLocal.points.perLayer[lyName];
        rpL.pointSize                   = slLocalPointSize->value();
        rpL.render_voxelmaps_as_points  = cbViewVoxelsAsPoints->checked();
        rpL.render_voxelmaps_free_space = cbViewVoxelsFreeSpace->checked();
        if (cbColorizeLocalMap->checked())
        {
            auto& cm                  = rpL.colorMode.emplace();
            cm.colorMap               = mrpt::img::TColormap::cmHOT;
            cm.recolorizeByCoordinate = mp2p_icp::Coordinate::Z;
        }
    }
 
    static mrpt::opengl::CSetOfObjects::Ptr lastLocalPts;
 
    if (!lastLocalPts || regenerateMaps)
    {
        // Show all or selected layers:
        for (auto& rpL : rpLocal.points.perLayer)
            rpL.second.color = mrpt::img::TColor(0x00, 0x00, 0xff, 0xff);
 
        auto glPts   = lr.pcLocal->get_visualization(rpLocal);
        lastLocalPts = glPts;
 
        glVizICP->insert(glPts);
    }
    else
    {
        // avoid the costly method of re-rendering maps, if possible:
        glVizICP->insert(lastLocalPts);
    }
    lastLocalPts->setPose(relativePose.mean);
 
    // Global view options:
    {
        std::lock_guard<std::mutex> lck(win->background_scene_mtx);
        win->camera().setCameraProjective(!cbViewOrtho->checked());
 
        if (cbCameraFollowsLocal->checked())
        {
            win->camera().setCameraPointing(
                relativePose.mean.x(), relativePose.mean.y(), relativePose.mean.z());
        }
 
        // clip planes:
        const auto depthFieldMid       = std::pow(10.0, slMidDepthField->value());
        const auto depthFieldThickness = std::pow(10.0, slThicknessDepthField->value());
 
        const auto clipNear = std::max(1e-2, depthFieldMid - 0.5 * depthFieldThickness);
        const auto clipFar  = depthFieldMid + 0.5 * depthFieldThickness;
 
        lbDepthFieldMid->setCaption(mrpt::format("Frustrum depth center: %.03f", depthFieldMid));
        lbDepthFieldThickness->setCaption(
            mrpt::format("Frustum depth thickness: %.03f", depthFieldThickness));
        lbDepthFieldValues->setCaption(
            mrpt::format("Frustum: near=%.02f far=%.02f", clipNear, clipFar));
 
        win->background_scene->getViewport()->setViewportClipDistances(clipNear, clipFar);
        win->camera().setMaximumZoom(std::max<double>(1000, 3.0 * clipFar));
    }
 
    // Pairings ------------------
 
    // viz pairings:
    if (pairsToViz)
    {
        mp2p_icp::pairings_render_params_t rp;
 
        rp.pt2pt.visible        = cbViewPairings_pt2pt->checked();
        rp.pt2pl.visible        = cbViewPairings_pt2pl->checked();
        rp.pt2pl.planePatchSize = std::pow(10.0, slPairingsPl2PlSize->value());
 
        rp.pt2ln.visible    = cbViewPairings_pt2ln->checked();
        rp.pt2ln.lineLength = std::pow(10.0, slPairingsPl2LnSize->value());
 
        glVizICP->insert(pairsToViz->get_visualization(relativePose.mean, rp));
 
        tbPairings->setValue(pairsToViz->contents_summary());
    }
    else
    {
        tbPairings->setValue("None selected (mark one of the checkboxes below)");
    }
 
    // XYZ corner overlay viewport:
    {
        auto gl_view = win->background_scene->createViewport("small-view");
 
        gl_view->setViewportPosition(0, 0, 0.1, 0.1 * 16.0 / 9.0);
        gl_view->setTransparent(true);
        {
            mrpt::opengl::CText::Ptr obj = mrpt::opengl::CText::Create("X");
            obj->setLocation(1.1, 0, 0);
            gl_view->insert(obj);
        }
        {
            mrpt::opengl::CText::Ptr obj = mrpt::opengl::CText::Create("Y");
            obj->setLocation(0, 1.1, 0);
            gl_view->insert(obj);
        }
        {
            mrpt::opengl::CText::Ptr obj = mrpt::opengl::CText::Create("Z");
            obj->setLocation(0, 0, 1.1);
            gl_view->insert(obj);
        }
        gl_view->insert(mrpt::opengl::stock_objects::CornerXYZ());
    }
}
 
#else  // MRPT_HAS_NANOGUI
static void main_show_gui()
{
    THROW_EXCEPTION(
        "This application requires a version of MRPT built with nanogui "
        "support.");
}
 
#endif  // MRPT_HAS_NANOGUI
 
int main(int argc, char** argv)
{
    try
    {
        // Parse arguments:
        if (!cmd.parse(argc, argv)) return 1;  // should exit.
 
        // Load plugins:
        if (arg_plugins.isSet())
        {
            std::string errMsg;
            const auto  plugins = arg_plugins.getValue();
            std::cout << "Loading plugin(s): " << plugins << std::endl;
            if (!mrpt::system::loadPluginModules(plugins, errMsg))
            {
                std::cerr << errMsg << std::endl;
                return 1;
            }
        }
 
        main_show_gui();
        return 0;
    }
    catch (std::exception& e)
    {
        std::cerr << "Exit due to exception:\n" << mrpt::exception_to_str(e) << std::endl;
        return 1;
    }
}