From b9d212427c51e2e0c36829eb79edeee32b5ca985 Mon Sep 17 00:00:00 2001
From: "r.kuznetsov" <r.kuznetsov@corp.mail.ru>
Date: Fri, 5 Aug 2016 15:09:59 -0700
Subject: [PATCH] Fixed follow-and-rotate animation jittering

---
 drape_frontend/animation/animation.hpp        | 6 ++++++
 drape_frontend/animation/follow_animation.cpp | 4 ++++
 drape_frontend/animation_system.cpp           | 8 +++++---
 drape_frontend/user_event_stream.cpp          | 2 ++
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/drape_frontend/animation/animation.hpp b/drape_frontend/animation/animation.hpp
index 3153dcf37b..8d788e55f6 100644
--- a/drape_frontend/animation/animation.hpp
+++ b/drape_frontend/animation/animation.hpp
@@ -76,6 +76,7 @@ public:
     : m_couldBeInterrupted(couldBeInterrupted)
     , m_couldBeBlended(couldBeBlended)
     , m_interruptedOnCombine(false)
+    , m_couldBeRewinded(true)
   {}
 
   virtual void OnStart() { if (m_onStartAction != nullptr) m_onStartAction(this); }
@@ -114,6 +115,9 @@ public:
 
   void SetCouldBeInterrupted(bool enable) { m_couldBeInterrupted = enable; }
   void SetCouldBeBlended(bool enable) { m_couldBeBlended = enable; }
+  
+  void SetCouldBeRewinded(bool enable) { m_couldBeRewinded = enable; }
+  bool CouldBeRewinded() const { return m_couldBeRewinded; }
 
 protected:
   TAction m_onStartAction;
@@ -126,6 +130,8 @@ protected:
   bool m_couldBeBlended;
   // Animation must be interrupted in case of combining another animation.
   bool m_interruptedOnCombine;
+  // Animation could be rewinded in case of finishing.
+  bool m_couldBeRewinded;
 };
 
 } // namespace df
diff --git a/drape_frontend/animation/follow_animation.cpp b/drape_frontend/animation/follow_animation.cpp
index 9054257fd0..d8da05fe65 100644
--- a/drape_frontend/animation/follow_animation.cpp
+++ b/drape_frontend/animation/follow_animation.cpp
@@ -41,6 +41,10 @@ MapFollowAnimation::MapFollowAnimation(ScreenBase const & screen,
     m_properties.insert(Animation::Angle);
   if (m_offsetInterpolator.IsActive() || m_scaleInterpolator.IsActive() || m_angleInterpolator.IsActive())
     m_properties.insert(Animation::Position);
+
+  // If MapFollowAnimation affects only angles, disable rewinding.
+  SetCouldBeRewinded(!m_angleInterpolator.IsActive() || m_scaleInterpolator.IsActive() ||
+                     m_offsetInterpolator.IsActive());
 }
 
 Animation::TObjectProperties const & MapFollowAnimation::GetProperties(TObject object) const
diff --git a/drape_frontend/animation_system.cpp b/drape_frontend/animation_system.cpp
index fd8e6b039b..b1acd5c1ff 100644
--- a/drape_frontend/animation_system.cpp
+++ b/drape_frontend/animation_system.cpp
@@ -270,7 +270,8 @@ void AnimationSystem::FinishAnimations(function<bool(shared_ptr<Animation> const
     if (predicate(anim))
     {
 #ifdef DEBUG_ANIMATIONS
-      LOG(LINFO, ("Finish animation", anim->GetType(), ", rewind:", rewind));
+      LOG(LINFO, ("Finish animation", anim->GetType(), ", rewind:", rewind,
+                  ", couldBeRewinded:", anim->CouldBeRewinded()));
       changed = true;
 #endif
       finishAnimations.splice(finishAnimations.end(), frontList, it++);
@@ -291,7 +292,8 @@ void AnimationSystem::FinishAnimations(function<bool(shared_ptr<Animation> const
         if (predicate(*it))
         {
 #ifdef DEBUG_ANIMATIONS
-          LOG(LINFO, ("Finish animation", (*it)->GetType(), ", rewind:", rewind));
+          LOG(LINFO, ("Finish animation", (*it)->GetType(), ", rewind:", rewind,
+                      ", couldBeRewinded:", anim->CouldBeRewinded()));
           changed = true;
 #endif
           it = lst.erase(it);
@@ -306,7 +308,7 @@ void AnimationSystem::FinishAnimations(function<bool(shared_ptr<Animation> const
 
   for (auto & anim : finishAnimations)
   {
-    if (rewind)
+    if (rewind && anim->CouldBeRewinded())
       anim->Finish();
     SaveAnimationResult(*anim);
   }
diff --git a/drape_frontend/user_event_stream.cpp b/drape_frontend/user_event_stream.cpp
index 63572d3a52..cd13b1ba52 100644
--- a/drape_frontend/user_event_stream.cpp
+++ b/drape_frontend/user_event_stream.cpp
@@ -390,7 +390,9 @@ bool UserEventStream::InterruptFollowAnimations(bool force)
         ResetAnimations(Animation::Arrow);
     }
     else
+    {
       return false;
+    }
   }
   return true;
 }