From 8efdddde39a70cd76c2aef5b6cecb9237d202054 Mon Sep 17 00:00:00 2001
From: Emil Axelsson <emil.axelsson@liu.se>
Date: Fri, 23 Sep 2016 00:27:06 +0200
Subject: [PATCH] avoid oversampling in time sync

---
 include/openspace/util/timemanager.h |  1 -
 src/util/timemanager.cpp             | 22 ++++++++++++++--------
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/include/openspace/util/timemanager.h b/include/openspace/util/timemanager.h
index 9e3d7dcc4b..5f863d22b9 100644
--- a/include/openspace/util/timemanager.h
+++ b/include/openspace/util/timemanager.h
@@ -35,7 +35,6 @@ public:
     void preSynchronization(double dt);
     void addKeyframe(const network::datamessagestructures::TimeKeyframe& kf);
     void removeKeyframesBefore(double timestamp);
-    void removeKeyframesAfter(double timestamp);
     void clearKeyframes();
 private:
     void consumeKeyframes(double dt);
diff --git a/src/util/timemanager.cpp b/src/util/timemanager.cpp
index ed619af340..bba05e72a8 100644
--- a/src/util/timemanager.cpp
+++ b/src/util/timemanager.cpp
@@ -26,6 +26,10 @@
 #include <openspace/engine/openspaceengine.h>
 #include <openspace/util/time.h>
 
+namespace {
+    double SecondsOffTolerance = 0.1;
+}
+
 namespace openspace {
 
 using network::datamessagestructures::TimeKeyframe;
@@ -73,10 +77,10 @@ void TimeManager::consumeKeyframes(double dt) {
 
             time.setPause(latest._paused);
             time.setTimeJumped(consumingTimeJump);
+            time.setDeltaTime(latest._dt);
 
             if (consumingTimeJump || latest._paused) {
                 time.setTime(latest._time, consumingTimeJump);
-                time.setDeltaTime(latest._dt);
             }
             _latestConsumedTimestamp = latest._timestamp;
         }
@@ -92,6 +96,14 @@ void TimeManager::consumeKeyframes(double dt) {
             return;
         }
 
+        double predictedTime = time.j2000Seconds() + time.deltaTime() * (next._timestamp - now);
+        bool withinTolerance = std::abs(predictedTime - next._time) < std::abs(next._dt * SecondsOffTolerance);
+        
+        if (next._dt == time.deltaTime() && withinTolerance) {
+            Time::ref().advanceTime(dt);
+            return;
+        }
+
         double t0 = now - dt;
         double t1 = now;
         double t2 = next._timestamp;
@@ -123,17 +135,11 @@ void TimeManager::addKeyframe(const TimeKeyframe& kf) {
     _keyframes.insert(iter, kf);
 }
 
-void TimeManager::removeKeyframesAfter(double timestamp) {
-    network::datamessagestructures::TimeKeyframe kf;
-    kf._timestamp = timestamp;
-    auto iter = std::upper_bound(_keyframes.begin(), _keyframes.end(), kf, &TimeManager::compareKeyframeTimes);
-    _keyframes.erase(iter, _keyframes.end());
-}
 
 void TimeManager::removeKeyframesBefore(double timestamp) {
     network::datamessagestructures::TimeKeyframe kf;
     kf._timestamp = timestamp;
-    auto iter = std::lower_bound(_keyframes.begin(), _keyframes.end(), kf, &TimeManager::compareKeyframeTimes);
+    auto iter = std::upper_bound(_keyframes.begin(), _keyframes.end(), kf, &TimeManager::compareKeyframeTimes);
     _keyframes.erase(_keyframes.begin(), iter);
 }