From 599ccea4a00d4e3b90e8a8eec96fb8e9cba5b64e Mon Sep 17 00:00:00 2001
From: "r.kuznetsov" <r.kuznetsov@corp.mail.ru>
Date: Thu, 25 Feb 2016 13:50:00 +0300
Subject: [PATCH] Optimized render bucket deletion

---
 drape_frontend/frontend_renderer.cpp | 14 ++++++++++++--
 drape_frontend/frontend_renderer.hpp |  1 +
 drape_frontend/render_group.cpp      |  5 ++++-
 drape_frontend/render_group.hpp      |  4 +++-
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/drape_frontend/frontend_renderer.cpp b/drape_frontend/frontend_renderer.cpp
index 7412c87097..5849018998 100755
--- a/drape_frontend/frontend_renderer.cpp
+++ b/drape_frontend/frontend_renderer.cpp
@@ -862,7 +862,8 @@ void FrontendRenderer::RenderScene(ScreenBase const & modelView)
   for (RenderLayer & layer : m_layers)
   {
     for (auto & group : layer.m_renderGroups)
-      layer.m_isDirty |= group->UpdateFeaturesWaitingStatus(isFeaturesWaiting, m_currentZoomLevel, make_ref(m_overlayTree));
+      layer.m_isDirty |= group->UpdateFeaturesWaitingStatus(isFeaturesWaiting, m_currentZoomLevel,
+                                                            make_ref(m_overlayTree), m_bucketsToDelete);
   }
 
   bool const isPerspective = modelView.isPerspective();
@@ -970,6 +971,15 @@ void FrontendRenderer::RenderScene(ScreenBase const & modelView)
 #endif
 
   MergeBuckets();
+
+  size_t const kMinDeletedPerFrame = 10;
+  size_t const kAvgDeletionFrameCount = 30;
+  size_t countToDelete = max(kMinDeletedPerFrame, m_bucketsToDelete.size() / kAvgDeletionFrameCount);
+  while (!m_bucketsToDelete.empty() && countToDelete > 0)
+  {
+    m_bucketsToDelete.pop_front();
+    countToDelete--;
+  }
 }
 
 void FrontendRenderer::Render2dLayer(ScreenBase const & modelView)
@@ -1382,7 +1392,7 @@ void FrontendRenderer::Routine::Do()
       m_renderer.PrepareScene(modelView);
 
     // Check for a frame is active.
-    bool isActiveFrame = modelViewChanged || viewportChanged;
+    bool isActiveFrame = modelViewChanged || viewportChanged || !m_renderer.m_bucketsToDelete.empty();
 
     isActiveFrame |= m_renderer.m_texMng->UpdateDynamicTextures();
     m_renderer.RenderScene(modelView);
diff --git a/drape_frontend/frontend_renderer.hpp b/drape_frontend/frontend_renderer.hpp
index aabfb46d5f..1f565a964b 100755
--- a/drape_frontend/frontend_renderer.hpp
+++ b/drape_frontend/frontend_renderer.hpp
@@ -250,6 +250,7 @@ private:
   array<RenderLayer, RenderLayer::LayerCountID> m_layers;
   vector<drape_ptr<UserMarkRenderGroup>> m_userMarkRenderGroups;
   set<TileKey> m_userMarkVisibility;
+  deque<drape_ptr<dp::RenderBucket>> m_bucketsToDelete;
 
   drape_ptr<gui::LayerRenderer> m_guiRenderer;
   drape_ptr<MyPositionController> m_myPositionController;
diff --git a/drape_frontend/render_group.cpp b/drape_frontend/render_group.cpp
index c9f91dcee4..c7167352d0 100755
--- a/drape_frontend/render_group.cpp
+++ b/drape_frontend/render_group.cpp
@@ -139,7 +139,9 @@ bool RenderGroup::IsLess(RenderGroup const & other) const
   return m_state < other.m_state;
 }
 
-bool RenderGroup::UpdateFeaturesWaitingStatus(TCheckFeaturesWaiting isFeaturesWaiting, int currentZoom, ref_ptr<dp::OverlayTree> tree)
+bool RenderGroup::UpdateFeaturesWaitingStatus(TCheckFeaturesWaiting isFeaturesWaiting,
+                                              int currentZoom, ref_ptr<dp::OverlayTree> tree,
+                                              deque<drape_ptr<dp::RenderBucket>> & bucketsToDelete)
 {
   if (!m_sharedFeaturesWaiting)
     return false;
@@ -156,6 +158,7 @@ bool RenderGroup::UpdateFeaturesWaitingStatus(TCheckFeaturesWaiting isFeaturesWa
     {
       m_renderBuckets[i]->RemoveOverlayHandles(tree);
       swap(m_renderBuckets[i], m_renderBuckets.back());
+      bucketsToDelete.push_back(move(m_renderBuckets.back()));
       m_renderBuckets.pop_back();
     }
     else
diff --git a/drape_frontend/render_group.hpp b/drape_frontend/render_group.hpp
index bff45dcc25..94ca0ff886 100755
--- a/drape_frontend/render_group.hpp
+++ b/drape_frontend/render_group.hpp
@@ -79,7 +79,9 @@ public:
   }
 
   using TCheckFeaturesWaiting = function<bool(m2::RectD const &)>;
-  bool UpdateFeaturesWaitingStatus(TCheckFeaturesWaiting isFeaturesWaiting, int currentZoom, ref_ptr<dp::OverlayTree> tree);
+  bool UpdateFeaturesWaitingStatus(TCheckFeaturesWaiting isFeaturesWaiting,
+                                   int currentZoom, ref_ptr<dp::OverlayTree> tree,
+                                   deque<drape_ptr<dp::RenderBucket>> & bucketsToDelete);
 
   bool IsLess(RenderGroup const & other) const;