From 9e54a981c6bf2e836a093647b2050ad19dc0c57d Mon Sep 17 00:00:00 2001
From: Arno Fleck <38908098+CodeArno@users.noreply.github.com>
Date: Mon, 9 Jul 2018 20:13:17 +0200
Subject: [PATCH] Introduce common::ToSeconds for
 std::chrono::steady_clock::duration. (#1244)

Introduce a new overload of ToSeconds for std::chrono::steady_clock and use it for the work queue delay metric.
---
 cartographer/common/time.cc                       | 5 +++++
 cartographer/common/time.h                        | 1 +
 cartographer/mapping/internal/2d/pose_graph_2d.cc | 4 +---
 cartographer/mapping/internal/3d/pose_graph_3d.cc | 4 +---
 4 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/cartographer/common/time.cc b/cartographer/common/time.cc
index 6874de2..8c2882d 100644
--- a/cartographer/common/time.cc
+++ b/cartographer/common/time.cc
@@ -31,6 +31,11 @@ double ToSeconds(const Duration duration) {
       .count();
 }
 
+double ToSeconds(const std::chrono::steady_clock::duration duration) {
+  return std::chrono::duration_cast<std::chrono::duration<double>>(duration)
+      .count();
+}
+
 Time FromUniversal(const int64 ticks) { return Time(Duration(ticks)); }
 
 int64 ToUniversal(const Time time) { return time.time_since_epoch().count(); }
diff --git a/cartographer/common/time.h b/cartographer/common/time.h
index 4939741..7fffcb9 100644
--- a/cartographer/common/time.h
+++ b/cartographer/common/time.h
@@ -49,6 +49,7 @@ Duration FromMilliseconds(int64 milliseconds);
 
 // Returns the given duration in seconds.
 double ToSeconds(Duration duration);
+double ToSeconds(std::chrono::steady_clock::duration duration);
 
 // Creates a time from a Universal Time Scale.
 Time FromUniversal(int64 ticks);
diff --git a/cartographer/mapping/internal/2d/pose_graph_2d.cc b/cartographer/mapping/internal/2d/pose_graph_2d.cc
index 7982d08..5319bb4 100644
--- a/cartographer/mapping/internal/2d/pose_graph_2d.cc
+++ b/cartographer/mapping/internal/2d/pose_graph_2d.cc
@@ -151,9 +151,7 @@ void PoseGraph2D::AddWorkItem(const std::function<void()>& work_item) {
     const auto now = std::chrono::steady_clock::now();
     work_queue_->push_back({now, work_item});
     kWorkQueueDelayMetric->Set(
-        std::chrono::duration_cast<std::chrono::duration<double>>(
-            now - work_queue_->front().time)
-            .count());
+        common::ToSeconds(now - work_queue_->front().time));
   }
 }
 
diff --git a/cartographer/mapping/internal/3d/pose_graph_3d.cc b/cartographer/mapping/internal/3d/pose_graph_3d.cc
index e29b193..5913669 100644
--- a/cartographer/mapping/internal/3d/pose_graph_3d.cc
+++ b/cartographer/mapping/internal/3d/pose_graph_3d.cc
@@ -149,9 +149,7 @@ void PoseGraph3D::AddWorkItem(const std::function<void()>& work_item) {
     const auto now = std::chrono::steady_clock::now();
     work_queue_->push_back({now, work_item});
     kWorkQueueDelayMetric->Set(
-        std::chrono::duration_cast<std::chrono::duration<double>>(
-            now - work_queue_->front().time)
-            .count());
+        common::ToSeconds(now - work_queue_->front().time));
   }
 }