From 3b009921ae5de2e8047904c25e671dee33deafa4 Mon Sep 17 00:00:00 2001
From: "r.kuznetsov" <r.kuznetsov@corp.mail.ru>
Date: Wed, 22 Apr 2015 14:21:12 +0300
Subject: [PATCH] Added stop rendering on FR while user is inactive

---
 drape_frontend/frontend_renderer.cpp | 43 +++++++++++++++++++---------
 drape_frontend/frontend_renderer.hpp |  2 +-
 drape_frontend/message_acceptor.cpp  | 18 ++++++++++++
 drape_frontend/message_acceptor.hpp  |  7 +++++
 drape_frontend/message_queue.cpp     |  6 ++++
 drape_frontend/message_queue.hpp     |  1 +
 6 files changed, 62 insertions(+), 15 deletions(-)

diff --git a/drape_frontend/frontend_renderer.cpp b/drape_frontend/frontend_renderer.cpp
index 5184793150..9a4b34787d 100755
--- a/drape_frontend/frontend_renderer.cpp
+++ b/drape_frontend/frontend_renderer.cpp
@@ -458,23 +458,31 @@ void FrontendRenderer::Routine::Do()
     context->setDefaultFramebuffer();
     m_renderer.m_textureManager->UpdateDynamicTextures();
     m_renderer.RenderScene();
-    m_renderer.UpdateScene();
+    bool const viewChanged = m_renderer.UpdateScene();
+    context->present();
 
-    double availableTime = VSyncInterval - (timer.ElapsedSeconds() /*+ avarageMessageTime*/);
-
-    if (availableTime < 0.0)
-      availableTime = 0.01;
-
-    while (availableTime > 0)
+    if (!viewChanged && m_renderer.IsQueueEmpty())
     {
-      m_renderer.ProcessSingleMessage(availableTime * 1000.0);
-      availableTime = VSyncInterval - (timer.ElapsedSeconds() /*+ avarageMessageTime*/);
-      //messageCount++;
+      // process a message or wait for a message
+      m_renderer.ProcessSingleMessage();
+    }
+    else
+    {
+      double availableTime = VSyncInterval - (timer.ElapsedSeconds() /*+ avarageMessageTime*/);
+
+      if (availableTime < 0.0)
+        availableTime = 0.01;
+
+      while (availableTime > 0)
+      {
+        m_renderer.ProcessSingleMessage(availableTime * 1000.0);
+        availableTime = VSyncInterval - (timer.ElapsedSeconds() /*+ avarageMessageTime*/);
+        //messageCount++;
+      }
+
+      //processingTime = (timer.ElapsedSeconds() - processingTime) / messageCount;
     }
 
-    //processingTime = (timer.ElapsedSeconds() - processingTime) / messageCount;
-
-    context->present();
     timer.Reset();
 
     m_renderer.CheckRenderingEnabled();
@@ -499,9 +507,14 @@ void FrontendRenderer::SetModelView(ScreenBase const & screen)
 {
   lock_guard<mutex> lock(m_modelViewMutex);
   m_newView = screen;
+
+  // check if view changed and cancel endless message waiting
+  bool const viewChanged = (m_view != m_newView);
+  if (viewChanged && IsInInfinityWaiting())
+    CancelMessageWaiting();
 }
 
-void FrontendRenderer::UpdateScene()
+bool FrontendRenderer::UpdateScene()
 {
   lock_guard<mutex> lock(m_modelViewMutex);
   if (m_view != m_newView)
@@ -516,7 +529,9 @@ void FrontendRenderer::UpdateScene()
     m_commutator->PostMessage(ThreadsCommutator::ResourceUploadThread,
                               make_unique_dp<UpdateReadManagerMessage>(m_view, move(tiles)),
                               MessagePriority::Normal);
+    return true;
   }
+  return false;
 }
 
 } // namespace df
diff --git a/drape_frontend/frontend_renderer.hpp b/drape_frontend/frontend_renderer.hpp
index 74f9ff4c72..4c76a18cd9 100755
--- a/drape_frontend/frontend_renderer.hpp
+++ b/drape_frontend/frontend_renderer.hpp
@@ -89,7 +89,7 @@ private:
 
 private:
   // it applies new model-view matrix to the scene (this matrix will be used on next frame)
-  void UpdateScene();
+  bool UpdateScene();
 
   void AddToRenderGroup(vector<drape_ptr<RenderGroup>> & groups,
                         dp::GLState const & state,
diff --git a/drape_frontend/message_acceptor.cpp b/drape_frontend/message_acceptor.cpp
index 09996d8aa1..adc5df902d 100644
--- a/drape_frontend/message_acceptor.cpp
+++ b/drape_frontend/message_acceptor.cpp
@@ -5,9 +5,17 @@
 namespace df
 {
 
+MessageAcceptor::MessageAcceptor()
+  : m_infinityWaiting(false)
+{
+}
+
 void MessageAcceptor::ProcessSingleMessage(unsigned maxTimeWait)
 {
+  m_infinityWaiting = (maxTimeWait == -1);
   drape_ptr<Message> message = m_messageQueue.PopMessage(maxTimeWait);
+  m_infinityWaiting = false;
+
   if (message == nullptr)
     return;
 
@@ -31,4 +39,14 @@ void MessageAcceptor::CancelMessageWaiting()
   m_messageQueue.CancelWait();
 }
 
+bool MessageAcceptor::IsInInfinityWaiting() const
+{
+  return m_infinityWaiting;
+}
+
+bool MessageAcceptor::IsQueueEmpty()
+{
+  return m_messageQueue.IsEmpty();
+}
+
 } // namespace df
diff --git a/drape_frontend/message_acceptor.hpp b/drape_frontend/message_acceptor.hpp
index 621055e0d3..06b10f551e 100644
--- a/drape_frontend/message_acceptor.hpp
+++ b/drape_frontend/message_acceptor.hpp
@@ -4,6 +4,8 @@
 
 #include "drape/pointers.hpp"
 
+#include "std/atomic.hpp"
+
 namespace df
 {
 
@@ -12,6 +14,7 @@ class Message;
 class MessageAcceptor
 {
 protected:
+  MessageAcceptor();
   virtual ~MessageAcceptor(){}
 
   virtual void AcceptMessage(ref_ptr<Message> message) = 0;
@@ -24,6 +27,9 @@ protected:
 
   void CloseQueue();
 
+  bool IsInInfinityWaiting() const;
+  bool IsQueueEmpty();
+
 private:
   friend class ThreadsCommutator;
 
@@ -31,6 +37,7 @@ private:
 
 private:
   MessageQueue m_messageQueue;
+  atomic<bool> m_infinityWaiting;
 };
 
 } // namespace df
diff --git a/drape_frontend/message_queue.cpp b/drape_frontend/message_queue.cpp
index 8f68a2bc0f..b1033c695b 100644
--- a/drape_frontend/message_queue.cpp
+++ b/drape_frontend/message_queue.cpp
@@ -53,6 +53,12 @@ void MessageQueue::PushMessage(drape_ptr<Message> && message, MessagePriority pr
     guard.Signal();
 }
 
+bool MessageQueue::IsEmpty()
+{
+  threads::ConditionGuard guard(m_condition);
+  return m_messages.empty();
+}
+
 void MessageQueue::WaitMessage(unsigned maxTimeWait)
 {
   if (m_messages.empty())
diff --git a/drape_frontend/message_queue.hpp b/drape_frontend/message_queue.hpp
index e6029ed655..2c8884f529 100644
--- a/drape_frontend/message_queue.hpp
+++ b/drape_frontend/message_queue.hpp
@@ -21,6 +21,7 @@ public:
   void PushMessage(drape_ptr<Message> && message, MessagePriority priority);
   void CancelWait();
   void ClearQuery();
+  bool IsEmpty();
 
 private:
   void WaitMessage(unsigned maxTimeWait);