visualization_msgs::MarkerArray markers;示例程序

以下是一个简单的示例程序，使用 `visualization_msgs::MarkerArray` 发布多个可视化标记：

#include <ros/ros.h>
#include <visualization_msgs/MarkerArray.h>

int main(int argc, char** argv)
{
  ros::init(argc, argv, "marker_array_publisher");
  ros::NodeHandle nh;
  ros::Publisher marker_pub = nh.advertise<visualization_msgs::MarkerArray>("markers", 10);

  // 创建多个标记
  visualization_msgs::Marker marker1, marker2, marker3;

  marker1.header.frame_id = "map";
  marker1.header.stamp = ros::Time();
  marker1.ns = "markers";
  marker1.id = 1;
  marker1.type = visualization_msgs::Marker::SPHERE;
  marker1.action = visualization_msgs::Marker::ADD;
  marker1.pose.position.x = 1.0;
  marker1.pose.position.y = 2.0;
  marker1.pose.position.z = 0.0;
  marker1.pose.orientation.x = 0.0;
  marker1.pose.orientation.y = 0.0;
  marker1.pose.orientation.z = 0.0;
  marker1.pose.orientation.w = 1.0;
  marker1.scale.x = 0.5;
  marker1.scale.y = 0.5;
  marker1.scale.z = 0.5;
  marker1.color.r = 1.0;
  marker1.color.g = 0.0;
  marker1.color.b = 0.0;
  marker1.color.a = 1.0;
  marker1.lifetime = ros::Duration();

  marker2.header.frame_id = "map";
  marker2.header.stamp = ros::Time();
  marker2.ns = "markers";
  marker2.id = 2;
  marker2.type = visualization_msgs::Marker::CYLINDER;
  marker2.action = visualization_msgs::Marker::ADD;
  marker2.pose.position.x = 3.0;
  marker2.pose.position.y = 4.0;
  marker2.pose.position.z = 0.0;
  marker2.pose.orientation.x = 0.0;
  marker2.pose.orientation.y = 0.0;
  marker2.pose.orientation.z = 0.0;
  marker2.pose.orientation.w = 1.0;
  marker2.scale.x = 0.5;
  marker2.scale.y = 0.5;
  marker2.scale.z = 1.0;
  marker2.color.r = 0.0;
  marker2.color.g = 1.0;
  marker2.color.b = 0.0;
  marker2.color.a = 1.0;
  marker2.lifetime = ros::Duration();

  marker3.header.frame_id = "map";
  marker3.header.stamp = ros::Time();
  marker3.ns = "markers";
  marker3.id = 3;
  marker3.type = visualization_msgs::Marker::ARROW;
  marker3.action = visualization_msgs::Marker::ADD;
  marker3.pose.position.x = 5.0;
  marker3.pose.position.y = 6.0;
  marker3.pose.position.z = 0.0;
  marker3.pose.orientation.x = 0.0;
  marker3.pose.orientation.y = 0.0;
  marker3.pose.orientation.z = 0.0;
  marker3.pose.orientation.w = 1.0;
  marker3.scale.x = 1.0;
  marker3.scale.y = 0.2;
  marker3.scale.z = 0.2;
  marker3.color.r = 0.0;
  marker3.color.g = 0.0;
  marker3.color.b = 1.0;
  marker3.color.a = 1.0;
  marker3.lifetime = ros::Duration();

  // 把所有的标记打包到单个 MarkerArray 消息中
  visualization_msgs::MarkerArray markers;
  markers.markers.push_back(marker1);
  markers.markers.push_back(marker2);
  markers.markers.push_back(marker3);

  // 发布 MarkerArray 消息
  while (ros::ok())
  {
    marker_pub.publish(markers);
    ros::spinOnce();
    ros::Duration(1).sleep();
  }

  return 0;
}

在这个示例程序中，我们定义了三个不同类型的标记：一个球体，一个圆柱体和一个箭头。每个标记都有其自己的位置，方向，大小和颜色。在程序的最后，我们把这些标记打包到一个单独的 `visualization_msgs::MarkerArray` 消息中，并在一个循环中不断发布它们，每秒发布一次。