Adds multi-trajectory support to offline mapping. (#204)

cartographer_ros/cartographer_ros/map_builder_bridge.cc

@@ -59,7 +59,7 @@ void MapBuilderBridge::WriteAssets(const string& stem) {
   if (trajectory_nodes.empty()) {
     LOG(WARNING) << "No data was collected and no assets will be written.";
   } else {
-    LOG(INFO) << "Writing assets to '" << stem << "'...";
+    LOG(INFO) << "Writing assets with stem '" << stem << "'...";
     cartographer_ros::WriteAssets(trajectory_nodes, options_, stem);
   }
 }

cartographer_ros/cartographer_ros/offline_node_main.cc

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include <sstream>
 #include <string>
 #include <vector>
 
@@ -37,8 +38,7 @@ DEFINE_string(configuration_directory, "",
 DEFINE_string(configuration_basename, "",
               "Basename, i.e. not containing any directory prefix, of the "
               "configuration file.");
-// TODO(damonkohler): Support multi-trajectory.
-DEFINE_string(bag_filename, "", "Bag to process.");
+DEFINE_string(bag_filenames, "", "Comma-separated list of bags to process.");
 DEFINE_string(
     urdf_filename, "",
     "URDF file that contains static links for your sensor configuration.");
@@ -49,8 +49,17 @@ namespace {
 constexpr int kLatestOnlyPublisherQueueSize = 1;
 constexpr char kClockTopic[] = "clock";
 
-void Run() {
-  // TODO(damonkohler): Pull out this common code across binaries.
+std::vector<string> SplitString(const string& input, const char delimiter) {
+  std::stringstream stream(input);
+  string token;
+  std::vector<string> tokens;
+  while (std::getline(stream, token, delimiter)) {
+    tokens.push_back(token);
+  }
+  return tokens;
+}
+
+void Run(std::vector<string> bag_filenames) {
   auto file_resolver = cartographer::common::make_unique<
       cartographer::common::ConfigurationFileResolver>(
       std::vector<string>{FLAGS_configuration_directory});
@@ -106,24 +115,27 @@ void Run() {
         node.node_handle()->resolveName(kOdometryTopic, false /* remap */));
   }
 
-  // TODO(damonkohler): Support multi-trajectory.
-  const int trajectory_id = node.map_builder_bridge()->AddTrajectory(
-      expected_sensor_ids, options.tracking_frame);
-
   ::ros::Publisher clock_publisher =
       node.node_handle()->advertise<rosgraph_msgs::Clock>(
           kClockTopic, kLatestOnlyPublisherQueueSize);
 
-  rosbag::Bag bag;
-  bag.open(FLAGS_bag_filename, rosbag::bagmode::Read);
-  for (const rosbag::MessageInstance& msg : rosbag::View(bag)) {
+  for (const string& bag_filename : bag_filenames) {
     if (!::ros::ok()) {
-      break;
+      return;
     }
 
-    const string& topic = node.node_handle()->resolveName(msg.getTopic());
-    if (expected_sensor_ids.count(
-            node.node_handle()->resolveName(msg.getTopic())) == 0) {
+    const int trajectory_id = node.map_builder_bridge()->AddTrajectory(
+        expected_sensor_ids, options.tracking_frame);
+    rosbag::Bag bag;
+    bag.open(bag_filename, rosbag::bagmode::Read);
+
+    for (const rosbag::MessageInstance& msg : rosbag::View(bag)) {
+      if (!::ros::ok()) {
+        return;
+      }
+
+      const string topic = node.node_handle()->resolveName(msg.getTopic());
+      if (expected_sensor_ids.count(topic) == 0) {
         continue;
       }
       if (msg.isType<sensor_msgs::LaserScan>()) {
@@ -148,7 +160,8 @@ void Run() {
       } else if (msg.isType<nav_msgs::Odometry>()) {
         node.map_builder_bridge()
             ->sensor_bridge(trajectory_id)
-          ->HandleOdometryMessage(topic, msg.instantiate<nav_msgs::Odometry>());
+            ->HandleOdometryMessage(topic,
+                                    msg.instantiate<nav_msgs::Odometry>());
       }
 
       rosgraph_msgs::Clock clock;
@@ -157,10 +170,12 @@ void Run() {
 
       ::ros::spinOnce();
     }
-  bag.close();
 
+    bag.close();
     node.map_builder_bridge()->FinishTrajectory(trajectory_id);
-  node.map_builder_bridge()->WriteAssets(FLAGS_bag_filename);
+  }
+
+  node.map_builder_bridge()->WriteAssets(bag_filenames.front());
 }
 
 }  // namespace
@@ -174,14 +189,15 @@ int main(int argc, char** argv) {
       << "-configuration_directory is missing.";
   CHECK(!FLAGS_configuration_basename.empty())
       << "-configuration_basename is missing.";
-  CHECK(!FLAGS_bag_filename.empty()) << "-bag_filename is missing.";
+  CHECK(!FLAGS_bag_filenames.empty()) << "-bag_filenames is missing.";
   CHECK(!FLAGS_urdf_filename.empty()) << "-urdf_filename is missing.";
 
   ::ros::init(argc, argv, "cartographer_offline_node");
   ::ros::start();
 
   cartographer_ros::ScopedRosLogSink ros_log_sink;
-  cartographer_ros::Run();
+  cartographer_ros::Run(
+      cartographer_ros::SplitString(FLAGS_bag_filenames, ','));
 
   ::ros::shutdown();
 }