Example: gui_nanogui_demo

See: Tutorial: 3D scenes

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/core/exceptions.h>
#include <mrpt/core/lock_helper.h>
#include <mrpt/gui/CDisplayWindowGUI.h>
#include <mrpt/opengl/CGridPlaneXY.h>
#include <mrpt/opengl/stock_objects.h>

#include <iostream>

#if MRPT_HAS_NANOGUI
void TestGUI()
{
    nanogui::init();

    {
        // Create main window:
        mrpt::gui::CDisplayWindowGUI_Params cp;
        // cp.fullscreen = true;

        mrpt::gui::CDisplayWindowGUI win(
            "CDisplayWindowGUI demo", 800, 600, cp);

        nanogui::FormHelper* fh = new nanogui::FormHelper(&win);

        // Add subwindow:
        nanogui::ref<nanogui::Window> subWin2 =
            fh->addWindow({300, 400}, "Test");
        subWin2->setLayout(new nanogui::GroupLayout());

        mrpt::gui::MRPT2NanoguiGLCanvas* glControl =
            subWin2->add<mrpt::gui::MRPT2NanoguiGLCanvas>();
        subWin2->setPosition({10, 300});

        {
            auto scene = mrpt::opengl::COpenGLScene::Create();
            scene->insert(mrpt::opengl::stock_objects::CornerXYZSimple());

            glControl->camera().setZoomDistance(5.0f);

            auto lck = mrpt::lockHelper(glControl->scene_mtx);
            glControl->scene = std::move(scene);
        }

        // Add subwindow:
        nanogui::ref<nanogui::Window> subWin =
            fh->addWindow({300, 400}, "Test");
        bool show_corner = true;

        fh->addGroup("Visualization");
        fh->addVariable("Show XYZ corner", show_corner)
            ->setCallback([&](const bool& c) { subWin2->setVisible(c); });

        fh->addButton("Quit", [&]() { win.setVisible(false); });

        subWin->setPosition({10, 10});

        // add a background scene:
        {
            auto scene = mrpt::opengl::COpenGLScene::Create();
            scene->insert(mrpt::opengl::CGridPlaneXY::Create());

            std::lock_guard<std::mutex> lck(win.background_scene_mtx);
            win.background_scene = std::move(scene);
        }

        win.performLayout();

        win.camera().setZoomDistance(10.0f);

        // Update view and process events:
        win.drawAll();
        win.setVisible(true);
        nanogui::mainloop();
    }

    nanogui::shutdown();
}
#endif

int main()
{
    try
    {
#if MRPT_HAS_NANOGUI
        TestGUI();
#else
        std::cerr << "This example requires MRPT built with NANOGUI.\n";
#endif
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << mrpt::exception_to_str(e) << std::endl;
        return -1;
    }
}