ui/compositor/layer_delegate.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_COMPOSITOR_LAYER_DELEGATE_H_
   6 #define UI_COMPOSITOR_LAYER_DELEGATE_H_
   7
   8 #include "base/callback_forward.h"
   9 #include "ui/compositor/compositor_export.h"
  10
  11 namespace gfx {
  12 class Canvas;
  13 class Rect;
  14 }
  15
  16 namespace ui {
  17
  18 // A delegate interface implemented by an object that renders to a Layer.
  19 class COMPOSITOR_EXPORT LayerDelegate {
  20  public:
  21   // Paint content for the layer to the specified canvas. It has already been
  22   // clipped to the Layer's invalid rect.
  23   virtual void OnPaintLayer(gfx::Canvas* canvas) = 0;
  24
  25   // A notification that this layer has had a delegated frame swap and
  26   // will be repainted.
  27   virtual void OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) = 0;
  28
  29   // Called when the layer's device scale factor has changed.
  30   virtual void OnDeviceScaleFactorChanged(float device_scale_factor) = 0;
  31
  32   // Invoked prior to the bounds changing. The returned closured is run after
  33   // the bounds change.
  34   virtual base::Closure PrepareForLayerBoundsChange() = 0;
  35
  36  protected:
  37   virtual ~LayerDelegate() {}
  38 };
  39
  40 }  // namespace ui
  41
  42 #endif  // UI_COMPOSITOR_LAYER_DELEGATE_H_