planning: added reference_line_info id, which is used to distinguish

virtual objects from different reference lines.

modules/planning/common/reference_line_info.cc

@@ -24,8 +24,16 @@
 
 namespace apollo {
 namespace planning {
+
+uint32_t ReferenceLineInfo::s_reference_line_id_ = 0;
+
 ReferenceLineInfo::ReferenceLineInfo(const ReferenceLine& reference_line)
-    : reference_line_(reference_line) {}
+    : reference_line_(reference_line) {
+  id_ = std::to_string(s_reference_line_id_);
+  ++s_reference_line_id_;
+}
+
+const std::string& ReferenceLineInfo::Id() const { return id_; }
 
 bool ReferenceLineInfo::AddObstacle(const Obstacle* obstacle) {
   auto path_obstacle = CreatePathObstacle(obstacle);

modules/planning/common/reference_line_info.h

@@ -36,6 +36,7 @@ namespace planning {
 class ReferenceLineInfo {
  public:
   explicit ReferenceLineInfo(const ReferenceLine& reference_line);
+  const std::string& Id() const;
   bool AddObstacles(const std::vector<const Obstacle*>& obstacles);
   bool AddObstacle(const Obstacle* obstacle);
   // FIXME(all) this interface is temp. solution to make the code work.
@@ -62,6 +63,10 @@ class ReferenceLineInfo {
   std::unique_ptr<PathObstacle> CreatePathObstacle(const Obstacle* obstacle);
   bool InitPerceptionSLBoundary(PathObstacle* path_obstacle);
 
+ private:
+  static uint32_t s_reference_line_id_;
+
+  std::string id_;
   /**
    * @brief this is the number that measures the goodness of this reference
    * line.