ROS探究（二）Clion编译项目

 1 在beginner_tutorials包中添加测试代码文件，参考cn/ROS/Tutorials/WritingPublisherSubscriber(c++) - ROS Wiki

tzy@ubuntu:~/ROS_Example/catkin_ws/src/beginner_tutorials/src$ ls
listener.cpp  talker.cpp

talker.cpp中我们尝试建立topic传输一个100M大文件内容test.log，代码如下

#include "ros/ros.h"
#include "std_msgs/String.h"

#include 
#include 

// 将整个文件读取出并转化成string
std::string FileToString(const std::string &filePath)
{
    std::ifstream input_stream(filePath.c_str(), std::ifstream::in);
    if (!input_stream.is_open())
    {
        return "";
    }
    std::ostringstream sstr;
    sstr << input_stream.rdbuf();
    return sstr.str();
}

int main(int argc, char **argv)
{
  ros::init(argc, argv, "talker");
  ros::NodeHandle n;

  ros::Publisher chatter_pub = n.advertise("chatter", 5);  // 每个文件100M大小，此处缓存队列不能太大

  ros::Rate loop_rate(10000);  // 加快循环频率 10000HZ，测试发送大字符串速度

  int count = 0;
  while (ros::ok())
  {
    std_msgs::String msg;
    std::stringstream ss;

    auto&& output = FileToString("test.log");  // test.log大概100M，使用右值引用优化内存

    ss<<"    size: "<" count: "<"+++++"<<output;  

    msg.data = ss.str();

    ROS_INFO("%s", msg.data.substr(0, 50).c_str());

    chatter_pub.publish(msg);

//    ros::spinOnce();  // spinonce时publish的信息会发送

    loop_rate.sleep();  //  loop_rate的sleep过程中publish会发送消息
    ++count;

    if(count > 1000)
        break;
  }

  ros::spin();  // 程序会卡在这里
  return 0;
}

listener.cpp进行接收

#include "ros/ros.h"
#include "std_msgs/String.h"

void chatterCallback(const std_msgs::String::ConstPtr& msg)
{
  ROS_INFO("I heard: [%s]", msg->data.substr(0, 50).c_str());
}

int main(int argc, char **argv)
{
  /**
   * The ros::init() function needs to see argc and argv so that it can perform
   * any ROS arguments and name remapping that were provided at the command line.
   * For programmatic remappings you can use a different version of init() which takes
   * remappings directly, but for most command-line programs, passing argc and argv is
   * the easiest way to do it.  The third argument to init() is the name of the node.
   *
   * You must call one of the versions of ros::init() before using any other
   * part of the ROS system.
   */
  ros::init(argc, argv, "listener");

  /**
   * NodeHandle is the main access point to communications with the ROS system.
   * The first NodeHandle constructed will fully initialize this node, and the last
   * NodeHandle destructed will close down the node.
   */
  ros::NodeHandle n;

  /**
   * The subscribe() call is how you tell ROS that you want to receive messages
   * on a given topic.  This invokes a call to the ROS
   * master node, which keeps a registry of who is publishing and who
   * is subscribing.  Messages are passed to a callback function, here
   * called chatterCallback.  subscribe() returns a Subscriber object that you
   * must hold on to until you want to unsubscribe.  When all copies of the Subscriber
   * object go out of scope, this callback will automatically be unsubscribed from
   * this topic.
   *
   * The second parameter to the subscribe() function is the size of the message
   * queue.  If messages are arriving faster than they are being processed, this
   * is the number of messages that will be buffered up before beginning to throw
   * away the oldest ones.
   */
  ros::Subscriber sub = n.subscribe("chatter", 1000, chatterCallback);

  /**
   * ros::spin() will enter a loop, pumping callbacks.  With this version, all
   * callbacks will be called from within this thread (the main one).  ros::spin()
   * will exit when Ctrl-C is pressed, or the node is shutdown by the master.
   */
  ros::spin();

  return 0;
}

在beginner_tutorials包的CMakeList.txt中添加如下内容

tzy@ubuntu:~/ROS_Example/catkin_ws/src/beginner_tutorials/src$ vim ../CMakeLists.txt 

add_executable(talker src/talker.cpp)
target_link_libraries(talker ${catkin_LIBRARIES})

add_executable(listener src/listener.cpp)
target_link_libraries(listener ${catkin_LIBRARIES})

2 编译

tzy@ubuntu:~/ROS_Example/catkin_ws$ catkin_make

生成的可执行文件在 ~/ROS_Example/catkin_ws/devel/lib/beginner_tutorials目录下

tzy@ubuntu:~/ROS_Example/catkin_ws/devel/lib/beginner_tutorials$ ls
listener  talker

3 测试

启动roscore

tzy@ubuntu:~/ROS_Example/catkin_ws$ roscore

启动listener

tzy@ubuntu:~/ROS_Example/catkin_ws$ source devel/setup.bash 
tzy@ubuntu:~/ROS_Example/catkin_ws$ rosrun beginner_tutorials listener 

启动talker

tzy@ubuntu:~/ROS_Example/catkin_ws$ source devel/setup.bash 
tzy@ubuntu:~/ROS_Example/catkin_ws$ rosrun beginner_tutorials talker

获得输出为

listener输出：
[ INFO] [1637052110.945022051]: I heard: [    size: 103943090 count: 0+++++618032 robot robo]
[ INFO] [1637052111.305311242]: I heard: [    size: 103943090 count: 1+++++618032 robot robo]
[ INFO] [1637052111.739413760]: I heard: [    size: 103943090 count: 2+++++618032 robot robo]
[ INFO] [1637052112.136378662]: I heard: [    size: 103943090 count: 3+++++618032 robot robo]
[ INFO] [1637052112.573668806]: I heard: [    size: 103943090 count: 4+++++618032 robot robo]
[ INFO] [1637052112.966500051]: I heard: [    size: 103943090 count: 5+++++618032 robot robo]
[ INFO] [1637052113.372856962]: I heard: [    size: 103943090 count: 6+++++618032 robot robo]
[ INFO] [1637052113.752406199]: I heard: [    size: 103943090 count: 7+++++618032 robot robo]
[ INFO] [1637052114.141449330]: I heard: [    size: 103943090 count: 8+++++618032 robot robo]
[ INFO] [1637052114.537786114]: I heard: [    size: 103943090 count: 9+++++618032 robot robo]
[ INFO] [1637052114.901102231]: I heard: [    size: 103943090 count: 10+++++618032 robot rob]
[ INFO] [1637052115.270014135]: I heard: [    size: 103943090 count: 11+++++618032 robot rob]
......

talker输出为：
[ INFO] [1637052110.740766881]:     size: 103943090 count: 0+++++618032 robot robo
[ INFO] [1637052111.161255732]:     size: 103943090 count: 1+++++618032 robot robo
[ INFO] [1637052111.573071874]:     size: 103943090 count: 2+++++618032 robot robo
[ INFO] [1637052111.984516081]:     size: 103943090 count: 3+++++618032 robot robo
[ INFO] [1637052112.409031092]:     size: 103943090 count: 4+++++618032 robot robo
[ INFO] [1637052112.808160636]:     size: 103943090 count: 5+++++618032 robot robo
[ INFO] [1637052113.206262870]:     size: 103943090 count: 6+++++618032 robot robo
[ INFO] [1637052113.598204760]:     size: 103943090 count: 7+++++618032 robot robo
[ INFO] [1637052113.990434510]:     size: 103943090 count: 8+++++618032 robot robo
[ INFO] [1637052114.370096664]:     size: 103943090 count: 9+++++618032 robot robo
[ INFO] [1637052114.748459862]:     size: 103943090 count: 10+++++618032 robot rob
[ INFO] [1637052115.120294768]:     size: 103943090 count: 11+++++618032 robot rob

4 使用clion打开项目

注意先要在命令行引入ROS环境变量并在命令行打开Clion

tzy@ubuntu:~$ source /opt/ros/kinetic/setup.bash 
tzy@ubuntu:~$ cd ide/clion-2019.1.4/bin/
tzy@ubuntu:~/ide/clion-2019.1.4/bin$ ./clion.sh 

项目打开路径为

 项目结构为

 加入Release编译选项

 编译并运行

效果跟在命令行运行相同。