From 7ea55eff17c28cb688f314e0904c160cba4c8952 Mon Sep 17 00:00:00 2001
From: rachytski <siarhei.rachytski@gmail.com>
Date: Fri, 28 Sep 2012 21:12:14 +0300
Subject: [PATCH] keeping anim::Controller pre-warmed for 5 cycles to allow new
 animations to start without interrupting rendering process.

---
 anim/controller.cpp   | 15 +++++++++++++++
 anim/controller.hpp   |  9 +++++++++
 map/render_policy.cpp | 10 ++++++----
 3 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/anim/controller.cpp b/anim/controller.cpp
index 9e246da4c2..3f217cf48c 100644
--- a/anim/controller.cpp
+++ b/anim/controller.cpp
@@ -10,6 +10,8 @@ namespace anim
   Controller::Controller()
   {
     m_LockCount = 0;
+    m_IdleThreshold = 5;
+    m_IdleFrames = 0;
   }
 
   Controller::~Controller()
@@ -19,6 +21,7 @@ namespace anim
   void Controller::AddTask(shared_ptr<Task> const & task)
   {
     m_tasks.PushBack(task);
+    m_IdleFrames = m_IdleThreshold;
   }
 
   void Controller::CopyAndClearTasks(TTasks & from, TTasks & to)
@@ -56,8 +59,12 @@ namespace anim
 
     TTasks l;
 
+    bool hasTasks = !m_tasksList.empty();
+
     for (TTasks::const_iterator it = m_tasksList.begin(); it != m_tasksList.end(); ++it)
     {
+      m_IdleFrames = m_IdleThreshold;
+
       shared_ptr<Task> const & task = *it;
       if (task->State() == Task::EStarted)
         task->OnStart(ts);
@@ -75,6 +82,14 @@ namespace anim
       }
     }
 
+    if (!hasTasks && m_IdleFrames > 0)
+      m_IdleFrames -= 1;
+
     m_tasks.ProcessList(bind(&Controller::CopyAndClearTasks, ref(l), _1));
   }
+
+  bool Controller::IsPreWarmed() const
+  {
+    return m_IdleFrames > 0;
+  }
 }
diff --git a/anim/controller.hpp b/anim/controller.hpp
index b93b19b71e..ff8a66e863 100644
--- a/anim/controller.hpp
+++ b/anim/controller.hpp
@@ -22,6 +22,8 @@ namespace anim
     TTasks m_tasksList;
 
     int m_LockCount;
+    int m_IdleThreshold;
+    int m_IdleFrames;
 
     static void CopyAndClearTasks(list<shared_ptr<Task> > & from, list<shared_ptr<Task> > & to);
 
@@ -44,5 +46,12 @@ namespace anim
     int LockCount();
     // Perform single animation step
     void PerformStep();
+    // When the last animation is finished, Controller continues
+    // to be considered animating something for some frames to allow
+    // animations that are likely to happen in the next few frames to
+    // catch the Controller up and animate everything smoothly without
+    // interrupting rendering process, which might had happened in these
+    // "frames-in-the-middle".
+    bool IsPreWarmed() const;
   };
 }
diff --git a/map/render_policy.cpp b/map/render_policy.cpp
index 7cc8513412..b182e8a442 100644
--- a/map/render_policy.cpp
+++ b/map/render_policy.cpp
@@ -99,12 +99,13 @@ void RenderPolicy::StopRotate(double a, double)
 
 void RenderPolicy::BeginFrame(shared_ptr<PaintEvent> const & e, ScreenBase const & s)
 {
-  /// processing animations at the beginning of the frame
-  m_controller->PerformStep();
 }
 
 void RenderPolicy::EndFrame(shared_ptr<PaintEvent> const & e, ScreenBase const & s)
-{}
+{
+  /// processing animations at the end of the frame
+  m_controller->PerformStep();
+}
 
 bool RenderPolicy::DoSupportRotation() const
 {
@@ -120,7 +121,8 @@ bool RenderPolicy::NeedRedraw() const
 bool RenderPolicy::IsAnimating() const
 {
   return (m_controller->HasTasks()
-      || (m_controller->LockCount() > 0));
+      || (m_controller->LockCount() > 0)
+      || (m_controller->IsPreWarmed()));
 }
 
 bool RenderPolicy::IsTiling() const