Example: opengl_ray_trace_example

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2023, 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/opengl/CAngularObservationMesh.h>
#include <mrpt/opengl/CAxis.h>
#include <mrpt/opengl/CCylinder.h>
#include <mrpt/opengl/CDisk.h>
#include <mrpt/opengl/CEllipsoid3D.h>
#include <mrpt/opengl/CGridPlaneXY.h>
#include <mrpt/opengl/CPolyhedron.h>
#include <mrpt/opengl/CSphere.h>
#include <mrpt/opengl/CTexturedPlane.h>
#include <mrpt/poses/CPoint3D.h>
#include <mrpt/poses/CPose3D.h>
#include <mrpt/random.h>
#include <mrpt/system/CTicTac.h>
#include <mrpt/system/os.h>

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

#define COLORR 1.0f
#define COLORG 0.0f
#define COLORB 0.0f

#define GRID_R 1.0f
#define GRID_G 1.0f
#define GRID_B 1.0f

using namespace std;
using namespace mrpt;
using namespace mrpt::gui;
using namespace mrpt::opengl;
using namespace mrpt::poses;
using namespace mrpt::math;
using namespace mrpt::random;
using namespace mrpt::serialization;
using namespace mrpt::system;

using mrpt::opengl::CAngularObservationMesh;

// Increase this values to get more precision. It will also increase run time.
const size_t HOW_MANY_YAWS = 150;
const size_t HOW_MANY_PITCHS = 75;

const float RANDOM_POSE_DISTANCE = 10;

inline double MYRAND1()
{
    //  return static_cast<float>(rand()%prec)/prec;
    return getRandomGenerator().drawUniform(0, 1);
}

inline double MYRANDG(double scale, double shift = 0)
{
    //  return shift+(static_cast<float>(rand()%prec)/prec)*scale;
    return shift + scale * getRandomGenerator().drawUniform(0, 1);
}

CPose3D randomPose()
{
    return CPose3D(
        MYRANDG(2 * RANDOM_POSE_DISTANCE, -RANDOM_POSE_DISTANCE),
        MYRANDG(2 * RANDOM_POSE_DISTANCE, -RANDOM_POSE_DISTANCE),
        MYRANDG(2 * RANDOM_POSE_DISTANCE, -RANDOM_POSE_DISTANCE), MYRAND1(),
        MYRAND1(), MYRAND1());
}

void configRandom(const CRenderizable::Ptr& obj)
{
    obj->setColor(MYRAND1(), MYRAND1(), MYRAND1(), MYRANDG(0.75, 0.25));
    obj->setPose(randomPose());
}

void guideLines(const CPose3D& base, CSetOfLines::Ptr& lines, float dist)
{
    CPoint3D pDist = CPoint3D(dist, 0, 0);
    CPoint3D pps[4];
    pps[0] = base + pDist;
    pps[1] = base + CPose3D(0, 0, 0, 0, -M_PI / 2, 0) + pDist;
    pps[2] = base + CPose3D(0, 0, 0, -M_PI / 2, 0, 0) + pDist;
    pps[3] = base + CPose3D(0, 0, 0, M_PI / 2, 0, 0) + pDist;
    for (size_t i = 0; i < 4; i++)
        lines->appendLine(
            base.x(), base.y(), base.z(), pps[i].x(), pps[i].y(), pps[i].z());
    lines->setLineWidth(5);
    lines->setColor(0, 0, 1);
}

// Add objects at your will to check results
void generateObjects(CSetOfObjects::Ptr& world)
{
    // create object, give it a random pose/color, insert it in the world
    CDisk::Ptr dsk = CDisk::Create();
    dsk->setDiskRadius(MYRANDG(5, 5), MYRANDG(5));
    configRandom(dsk);
    world->insert(dsk);

    CSphere::Ptr sph = CSphere::Create(MYRANDG(5, 1));
    configRandom(sph);
    world->insert(sph);

    CTexturedPlane::Ptr pln = CTexturedPlane::Create(
        MYRANDG(10, -10), MYRANDG(10), MYRANDG(10, -10), MYRANDG(10));
    configRandom(pln);
    world->insert(pln);

    for (size_t i = 0; i < 5; i++)
    {
        CPolyhedron::Ptr poly =
            CPolyhedron::CreateRandomPolyhedron(MYRANDG(2, 2));
        configRandom(poly);
        world->insert(poly);
    }

    CCylinder::Ptr cil = CCylinder::Create(
        MYRANDG(3.0, 3.0), MYRANDG(3.0, 1.0), MYRANDG(2.0f, 3.0f), 50);
    configRandom(cil);
    world->insert(cil);

    CEllipsoid3D::Ptr ell = CEllipsoid3D::Create();
    CMatrixDouble md = CMatrixDouble(3, 3);
    for (size_t i = 0; i < 3; i++)
        md(i, i) = MYRANDG(8.0, 1.0);
    for (size_t i = 0; i < 3; i++)
    {
        size_t ii = (i + 1) % 3;
        md(i, ii) = md(ii, i) = MYRANDG(sqrt(md(i, i) * md(ii, ii)));
    }
    ell->setCovMatrix(md);
    configRandom(std::dynamic_pointer_cast<CRenderizable>(ell));
    world->insert(ell);
}

void display()
{
    CDisplayWindow3D window("Ray trace demo", 640, 480);
    window.setPos(10, 10);
    std::this_thread::sleep_for(20ms);
    Scene::Ptr scene1 = Scene::Create();
    // Scene::Ptr &scene1=window.get3DSceneAndLock();
    opengl::CGridPlaneXY::Ptr plane1 =
        CGridPlaneXY::Create(-20, 20, -20, 20, 0, 1);
    plane1->setColor(GRID_R, GRID_G, GRID_B);
    scene1->insert(plane1);
    scene1->insert(CAxis::Create(-5, -5, -5, 5, 5, 5, 2.5, 3, true));
    CSetOfObjects::Ptr world = CSetOfObjects::Create();
    generateObjects(world);
    scene1->insert(world);
    CPose3D basePose = randomPose();
    CAngularObservationMesh::Ptr aom = CAngularObservationMesh::Create();
    CTicTac t;
    t.Tic();
    CAngularObservationMesh::trace2DSetOfRays(
        scene1, basePose, aom,
        CAngularObservationMesh::TDoubleRange::CreateFromAmount(
            -M_PI / 2, 0, HOW_MANY_PITCHS),
        CAngularObservationMesh::TDoubleRange::CreateFromAperture(
            M_PI, HOW_MANY_YAWS));
    cout << "Elapsed time: " << t.Tac() << " seconds.\n";
    aom->setColor(0, 1, 0);
    aom->setWireframe(true);
    // Comment to stop showing traced rays and scan range guidelines.
    CSetOfLines::Ptr traced = CSetOfLines::Create();
    CSetOfLines::Ptr guides = CSetOfLines::Create();
    aom->getTracedRays(traced);
    traced->setLineWidth(1.5);
    traced->setColor(1, 0, 0);
    guideLines(basePose, guides, 10);
    scene1->insert(traced);
    scene1->insert(guides);

    // Uncomment to show also traced rays who got lost.
    /*
    CSetOfLines::Ptr untraced=CSetOfLines::Create();
    aom->getUntracedRays(untraced,20);
    untraced->setLineWidth(1);
    untraced->setColor(1,1,1,0.5);
    scene1->insert(untraced);
    */
    CSphere::Ptr point = CSphere::Create(0.2);
    point->setColor(0, 1, 0);
    point->setPose(basePose);
    scene1->insert(point);
    CDisplayWindow3D window2("Observed mesh", 640, 480);
    window2.setPos(660, 10);
    std::this_thread::sleep_for(20ms);
    window.get3DSceneAndLock() = scene1;
    window.unlockAccess3DScene();
    window.setCameraElevationDeg(25.0f);
    Scene::Ptr& scene2 = window2.get3DSceneAndLock();
    scene2->insert(aom);
    opengl::CGridPlaneXY::Ptr plane2 =
        CGridPlaneXY::Create(-20, 20, -20, 20, 0, 1);
    plane2->setColor(GRID_R, GRID_G, GRID_B);
    scene2->insert(plane2);
    scene2->insert(CAxis::Create(-5, -5, -5, 5, 5, 5, 2.5, 3, true));
    window2.unlockAccess3DScene();
    window2.setCameraElevationDeg(25.0f);

    window.waitForKey();
}

int main()
{
    mrpt::random::getRandomGenerator().randomize();
    try
    {
        display();
        return 0;
    }
    catch (const exception& e)
    {
        cout << "Error: " << e.what() << '.' << endl;
        mrpt::system::pause();
        return -1;
    }
    catch (...)
    {
        cout << "Unknown Error.\n";
        return -1;
    }
}