plotTrajectory.cpp

#include <pangolin/pangolin.h>
#include <Eigen/Core>
#include <unistd.h>

using namespace std;
using namespace Eigen;

string trajectory_file = "./examples/data/trajectory.txt";

void DrawTrajectory(vector<Isometry3d, Eigen::aligned_allocator<Isometry3d>>);

int main(int argc, char **argv)
{
    vector<Isometry3d, Eigen::aligned_allocator<Isometry3d>> poses;

    ifstream fin(trajectory_file);
    if (!fin)
    {
        cerr << "Cannot open file: " << trajectory_file << endl;
        return 1;
    }

    while (!fin.eof())
    {
        double time, tx, ty, tz, qx, qy, qz, qw;

        fin >> time >> tx >> ty >> tz >> qx >> qy >> qz >> qw;

        Isometry3d Twr(Quaterniond(qw, qx, qy, qz));
        Twr.pretranslate(Vector3d(tx, ty, tz));
        poses.push_back(Twr);
    }

    cout << "Read " << poses.size() << " poses." << endl;

    DrawTrajectory(poses);

    return 0;
}

void DrawTrajectory(vector<Isometry3d, Eigen::aligned_allocator<Isometry3d>> poses)
{
    pangolin::CreateWindowAndBind("Trajectory Viewer", 1024, 768);

    glEnable(GL_DEPTH_TEST);
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    pangolin::OpenGlRenderState s_cam(
        pangolin::ProjectionMatrix(1024, 768, 500, 500, 512, 389, 0.1, 1000),
        pangolin::ModelViewLookAt(0, -0.1, -1.8, 0, 0, 0, 0.0, -1.0, 0.0));

    pangolin::View &d_cam = pangolin::CreateDisplay()
                                .SetBounds(0.0, 1.0, pangolin::Attach::Pix(175), 1.0, -1024.0f / 768.0f)
                                .SetHandler(new pangolin::Handler3D(s_cam));

    while (!pangolin::ShouldQuit())
    {
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        d_cam.Activate(s_cam);
        glClearColor(1.0f, 1.0f, 1.0f, 1.0f);

        glLineWidth(2);
        for (size_t i = 0; i < poses.size(); i++)
        {
            Vector3d Ow = poses[i].translation();
            Vector3d Xw = poses[i] * (0.1 * Vector3d(1, 0, 0));
            Vector3d Yw = poses[i] * (0.1 * Vector3d(0, 1, 0));
            Vector3d Zw = poses[i] * (0.1 * Vector3d(0, 0, 1));

            glBegin(GL_LINES);

            glColor3f(1.0f, 0.0f, 0.0f);
            glVertex3d(Ow[0], Ow[1], Ow[2]);
            glVertex3d(Xw[0], Xw[1], Xw[2]);
            glColor3f(0.0, 1.0, 0.0);
            glVertex3d(Ow[0], Ow[1], Ow[2]);
            glVertex3d(Yw[0], Yw[1], Yw[2]);
            glColor3f(0.0, 0.0, 1.0);
            glVertex3d(Ow[0], Ow[1], Ow[2]);
            glVertex3d(Zw[0], Zw[1], Zw[2]);
            glEnd();
        }

#draw a connection

        for (size_t i = 0; i < poses.size() - 1; i++)
        {
            glColor3f(0.0f, 0.0f, 0.0f);
            glBegin(GL_LINES);

            auto p1 = poses[i], p2 = poses[i + 1];
            glVertex3d(p1.translation()[0], p1.translation()[1], p1.translation()[2]);
            glVertex3d(p2.translation()[0], p2.translation()[1], p2.translation()[2]);
            glEnd();
        }

        pangolin::FinishFrame();
        usleep(5000); // sleep 5 ms
    }
}