Animated Rotation

views/view.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef VIEWS_VIEW_H_
 #define VIEWS_VIEW_H_
 #pragma once
 
 #include <algorithm>
 #include <map>
@@ skipping 1086 matching lines @@
   // used by the public static method ExceededDragThreshold().
   static int GetHorizontalDragThreshold();
   static int GetVerticalDragThreshold();
 
  private:
   friend class internal::NativeWidgetView;
   friend class internal::RootView;
   friend class FocusManager;
   friend class ViewStorage;
   friend class Widget;
+  friend class PaintLock;
 
   // Used to track a drag. RootView passes this into
   // ProcessMousePressed/Dragged.
   struct DragInfo {
     // Sets possible_drag to false and start_x/y to 0. This is invoked by
     // RootView prior to invoke ProcessMousePressed.
     void Reset();
 
     // Sets possible_drag to true and start_pt to the specified point.
     // This is invoked by the target view if it detects the press may generate
@@ skipping 105 matching lines @@
   bool ConvertPointForAncestor(const View* ancestor, gfx::Point* point) const;
 
   // Convert a point in the ancestor's coordinate system to the view's
   // coordinate system using necessary transformations. Returns whether the
   // point was successfully from the ancestor's coordinate system to the view's
   // coordinate system.
   bool ConvertPointFromAncestor(const View* ancestor, gfx::Point* point) const;
 
   // Accelerated painting ------------------------------------------------------
 
+  // Disables painting during time-critical operations. Used by PaintLock.
+  void set_painting_enabled(bool enabled) { painting_enabled_ = enabled; }

[Ben Goodger (Google), 2011/08/31 20:34:00]

It troubles me that we need this.

It seems like the widget should just not dispatch paints into the hierarchy when
a time critical operation is underway. The widget can know this because it owns
(or has a link to) the compositor.

Can you add a TODO() to revisit this.

+
   // Returns true if this view should paint to layer.
   bool ShouldPaintToLayer() const;
 
   // Creates the layer and related fields for this view.
   void CreateLayer();
 
   // Reparents any descendant layer to our current layer parent and destroys
   // this views layer.
   void DestroyLayerAndReparent();
 
@@ skipping 104 matching lines @@
 
   // This View's bounds in the parent coordinate system.
   gfx::Rect bounds_;
 
   // Whether this view is visible.
   bool visible_;
 
   // Whether this view is enabled.
   bool enabled_;
 
+  // Whether this view is painting.
+  bool painting_enabled_;
+
   // Whether or not RegisterViewForVisibleBoundsNotification on the RootView
   // has been invoked.
   bool registered_for_visible_bounds_notification_;
 
   // List of descendants wanting notification when their visible bounds change.
   scoped_ptr<Views> descendants_to_notify_;
 
   // Transformations -----------------------------------------------------------
 
   // Clipping parameters. skia transformation matrix does not give us clipping.
@@ skipping 74 matching lines @@
 #if defined(OS_WIN)
   scoped_refptr<NativeViewAccessibilityWin> native_view_accessibility_win_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace views
 
 #endif  // VIEWS_VIEW_H_