Merge lp:~vanvugt/nux/fix-1014610 into lp:nux

[Daniel van Vugt]

Don't allow a View to be queued multiple times on the draw list. It causes
unbounded list growth and the UI to freeze in some cases. (LP: #1014610)

This fix not only eliminates the pauses I experience, but also seems to improve the performance of Unity in general.

For example, opening the dash:
Before the fix: spikes to a DrawList size of around 300
After the fix: spikes to only 30

[lp:~vanvugt/nux/fix-1014610]

624. By Daniel van Vugt on 2012-06-18

Add test for LP: #1014610

[Tim Penhey (thumper)]

Looks good.

review: Approve

=== modified file 'Nux/View.cpp'
--- Nux/View.cpp	2012-06-12 09:13:06 +0000
+++ Nux/View.cpp	2012-06-18 12:43:42 +0000
@@ -216,6 +216,9 @@
 
   void View::QueueDraw()
   {
+    if (draw_cmd_queued_)
+      return;
+
     //GetWindowCompositor()..AddToDrawList(this);
     WindowThread* application = GetWindowThread();
     if (application)

=== modified file 'tests/gtest-nux-view.cpp'
--- tests/gtest-nux-view.cpp	2012-06-12 18:22:56 +0000
+++ tests/gtest-nux-view.cpp	2012-06-18 12:43:42 +0000
@@ -65,6 +65,17 @@
   EXPECT_EQ(test_view2->calls_to_queue_draw_, 1);
   EXPECT_EQ(test_view3->calls_to_queue_draw_, 1);
 
+  int old_size = wnd_thread->GetDrawList().size();
+  main_view->QueueDraw();
+  test_view2->QueueDraw();
+  int new_size = wnd_thread->GetDrawList().size();
+  EXPECT_EQ(old_size, new_size);  // LP: #1014610
+
+  EXPECT_EQ(main_view->calls_to_queue_draw_, 2);
+  EXPECT_EQ(test_view1->calls_to_queue_draw_, 1);
+  EXPECT_EQ(test_view2->calls_to_queue_draw_, 2);
+  EXPECT_EQ(test_view3->calls_to_queue_draw_, 1);
+
   main_view->UnReference();
   delete wnd_thread;
 }