Example: hwdrivers_openni2_driver_demo

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2022, 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.h>
#include <mrpt/hwdrivers/COpenNI2Sensor.h>
#include <mrpt/img/TColor.h>
#include <mrpt/opengl.h>
#include <mrpt/system/CTicTac.h>

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

using namespace mrpt;
using namespace mrpt::obs;
using namespace mrpt::opengl;
using namespace mrpt::hwdrivers;
using namespace mrpt::system;
using namespace mrpt::img;
using namespace std;

// This simple demo records form an OpenNI2 device into a rawlog as 3D
// observations. It's meant as a temporary workaround before OpenNI2 is
// integrated as a generic sensor so that it works with rawlog-grabber.

int main(int argc, char** argv)
{
    try
    {
        if (argc > 2)
        {
            cerr << "Usage: " << argv[0] << " <sensor_id/sensor_serial\n";
            cerr << "Example: " << argv[0] << " 0 \n";
            return 1;
        }

        // const unsigned sensor_id = 0;
        COpenNI2Sensor rgbd_sensor;
        //    rgbd_sensor.loadConfig_sensorSpecific(const
        //    mrpt::config::CConfigFileBase &configSource,  const std::string
        //    &iniSection );

        unsigned sensor_id_or_serial = 0;
        //      const string configFile = std::string( argv[2] );
        if (argc == 2)
        {
            sensor_id_or_serial = atoi(argv[1]);
            if (sensor_id_or_serial > 10)
                rgbd_sensor.setSerialToOpen(sensor_id_or_serial);
            else
                rgbd_sensor.setSensorIDToOpen(sensor_id_or_serial);
        }

        // Open:
        // cout << "Calling COpenNI2Sensor::initialize()...";
        rgbd_sensor.initialize();

        if (rgbd_sensor.getNumDevices() == 0) return 0;

        cout << "OK " << rgbd_sensor.getNumDevices() << " available devices."
             << endl;
        cout << "\nUse device " << sensor_id_or_serial << endl << endl;

        bool showImages = false;
        if (showImages)
        {
            mrpt::gui::CDisplayWindow win("Video");

            CTicTac tictac;
            tictac.Tic();
            unsigned int nFrames = 0;
            CObservation3DRangeScan newObs;
            bool bObs = false, bError = true;
            rgbd_sensor.getNextObservation(newObs, bObs, bError);

            while (!system::os::kbhit())
            {
                cout << "Get a new frame\n";
                rgbd_sensor.getNextObservation(newObs, bObs, bError);

                double fps = ++nFrames / tictac.Tac();
                //      newObs->intensityImage.textOut(5,5,format("%.02f
                //      fps",fps),TColor(0x80,0x80,0x80) );
                cout << "FPS: " << fps << endl;

                if (nFrames > 100)
                {
                    tictac.Tic();
                    nFrames = 0;
                }

                win.showImage(newObs.intensityImage);
                std::this_thread::sleep_for(10ms);
            }
        }
        else  // Show point cloud and images
        {
            // Create window and prepare OpenGL object in the scene:
            // --------------------------------------------------------
            mrpt::gui::CDisplayWindow3D win3D("OpenNI2 3D view", 800, 600);

            win3D.setCameraAzimuthDeg(140);
            win3D.setCameraElevationDeg(20);
            win3D.setCameraZoom(8.0);
            win3D.setFOV(90);
            win3D.setCameraPointingToPoint(2.5, 0, 0);

            mrpt::opengl::CPointCloudColoured::Ptr gl_points =
                mrpt::opengl::CPointCloudColoured::Create();
            gl_points->setPointSize(2.5);

            opengl::COpenGLViewport::Ptr
                viewInt;  // Extra viewports for the RGB images.
            {
                mrpt::opengl::COpenGLScene::Ptr& scene =
                    win3D.get3DSceneAndLock();

                // Create the Opengl object for the point cloud:
                scene->insert(gl_points);
                scene->insert(mrpt::opengl::CGridPlaneXY::Create());
                scene->insert(mrpt::opengl::stock_objects::CornerXYZ());

                const double aspect_ratio = 480.0 / 640.0;
                const int VW_WIDTH = 400;  // Size of the viewport into the
                // window, in pixel units.
                const int VW_HEIGHT = aspect_ratio * VW_WIDTH;

                // Create an extra opengl viewport for the RGB image:
                viewInt = scene->createViewport("view2d_int");
                viewInt->setViewportPosition(5, 30, VW_WIDTH, VW_HEIGHT);
                win3D.addTextMessage(
                    10, 30 + VW_HEIGHT + 10, "Intensity data", 2);

                win3D.addTextMessage(
                    5, 5, "'o'/'i'-zoom out/in, ESC: quit", 110);

                win3D.unlockAccess3DScene();
                win3D.repaint();
            }

            //                          Grab frames continuously and show
            //========================================================================================

            bool bObs = false, bError = true;
            mrpt::system::TTimeStamp last_obs_tim = INVALID_TIMESTAMP;

            while (!win3D.keyHit())  // Push any key to exit // win3D.isOpen()
            {
                //    cout << "Get new observation\n";
                CObservation3DRangeScan::Ptr newObs =
                    CObservation3DRangeScan::Create();
                rgbd_sensor.getNextObservation(*newObs, bObs, bError);

                if (bObs && !bError && newObs &&
                    newObs->timestamp != INVALID_TIMESTAMP &&
                    newObs->timestamp != last_obs_tim)
                {
                    // It IS a new observation:
                    last_obs_tim = newObs->timestamp;

                    // Update visualization
                    // ---------------------------------------

                    win3D.get3DSceneAndLock();

                    // Estimated grabbing rate:
                    win3D.addTextMessage(
                        -350, -13,
                        format(
                            "Timestamp: %s",
                            mrpt::system::dateTimeLocalToString(last_obs_tim)
                                .c_str()),
                        100);

                    // Show intensity image:
                    if (newObs->hasIntensityImage)
                    {
                        viewInt->setImageView(
                            newObs->intensityImage);  // This is not "_fast"
                        // since the intensity
                        // image may be needed
                        // later on.
                    }
                    win3D.unlockAccess3DScene();

                    // -------------------------------------------------------
                    //           Create 3D points from RGB+D data
                    //
                    // There are several methods to do this.
                    //  Switch the #if's to select among the options:
                    // See also:
                    // https://www.mrpt.org/Generating_3D_point_clouds_from_RGB_D_observations
                    // -------------------------------------------------------
                    if (newObs->hasRangeImage)
                    {
#if 0
            static pcl::PointCloud<pcl::PointXYZRGB> cloud;
            newObs->unprojectInto(cloud, false /* without obs.sensorPose */);

            win3D.get3DSceneAndLock();
              gl_points->loadFromPointsMap(&cloud);
            win3D.unlockAccess3DScene();
#endif

// Pathway: RGB+D --> XYZ+RGB opengl
#if 1
                        win3D.get3DSceneAndLock();
                        mrpt::obs::T3DPointsProjectionParams pp;
                        pp.takeIntoAccountSensorPoseOnRobot = false;
                        newObs->unprojectInto(
                            *gl_points, pp /* without obs.sensorPose */);
                        win3D.unlockAccess3DScene();
#endif
                    }

                    win3D.repaint();
                }  // end update visualization:
            }
        }

        cout << "\nClosing RGBD sensor...\n";

        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << "MRPT error: " << mrpt::exception_to_str(e) << std::endl;
        return -1;
    }
}