Function trackingCallback

opt_utils/apps/ros2udp_converter_objects.cpp:66–123

void
trackingCallback(const opt_msgs::TrackArray::ConstPtr& tracking_msg)
{
    /// Create JSON-formatted message:
    Jzon::Object root, header, stamp;

    /// Add header (84 characters):
    header.Add("seq", int(tracking_msg->header.seq));
    stamp.Add("sec", int(tracking_msg->header.stamp.sec));
    stamp.Add("nsec", int(tracking_msg->header.stamp.nsec));
    header.Add("stamp", stamp);
    header.Add("frame_id", tracking_msg->header.frame_id);
    root.Add("header", header);

    /// Add tracks array:
    // >50 characters for every track
    Jzon::Array tracks;


    for (unsigned int i = 0; i < tracking_msg->tracks.size(); i++)
    {
        Jzon::Object current_track;
        int index_roiname=tracking_msg->tracks[i].id;
        current_track.Add("id", index_roiname);
        current_track.Add("object_name",tracking_msg->tracks[i].object_name);
        current_track.Add("x", tracking_msg->tracks[i].x);
        current_track.Add("y", tracking_msg->tracks[i].y);
        current_track.Add("height", tracking_msg->tracks[i].height);
        current_track.Add("age", tracking_msg->tracks[i].age);
        current_track.Add("confidence", 0.0);
        tracks.Add(current_track);
    }
    root.Add("object_tracks", tracks);

    /// Convert JSON object to string:
    Jzon::Format message_format = Jzon::StandardFormat;
    message_format.indentSize = json_indent_size;
    message_format.newline = json_newline;
    message_format.spacing = json_spacing;
    message_format.useTabs = json_use_tabs;
    Jzon::Writer writer(root, message_format);
    writer.Write();
    std::string json_string = writer.GetResult();
    //  std::cout << "String sent: " << json_string << std::endl;

    /// Copy string to message buffer:
    udp_data.si_num_byte_ = json_string.length()+1;
    char buf[udp_data.si_num_byte_];
    for (unsigned int i = 0; i < udp_data.si_num_byte_; i++)
    {
        buf[i] = 0;
    }
    sprintf(buf, "%s", json_string.c_str());
    udp_data.pc_pck_ = buf;         // buffer where the message is written

    /// Send message:
    udp_messaging.sendFromSocketUDP(&udp_data);
}