ui/compositor/compositing_recorder.h

   1 // Copyright 2015 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_COMPOSITING_RECORDER_H_
   6 #define UI_COMPOSITOR_COMPOSITING_RECORDER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/macros.h"
  10 #include "ui/compositor/compositor_export.h"
  11
  12 namespace ui {
  13 class PaintContext;
  14
  15 // A class to provide scoped compositing filters (eg opacity) of painting to a
  16 // DisplayItemList. The filters provided will be applied to any
  17 // DisplayItems added to the DisplayItemList while this object is alive. In
  18 // other words, any nested PaintRecorders or other such Recorders will
  19 // be filtered by the effect.
  20 class COMPOSITOR_EXPORT CompositingRecorder {
  21  public:
  22   // |alpha| is a value between 0 and 255, where 0 is transparent and 255 is
  23   // opaque.
  24   CompositingRecorder(const PaintContext& context, uint8_t alpha);
  25   ~CompositingRecorder();
  26
  27  private:
  28   const PaintContext& context_;
  29   bool saved_;
  30
  31   DISALLOW_COPY_AND_ASSIGN(CompositingRecorder);
  32 };
  33
  34 }  // namespace ui
  35
  36 #endif  // UI_COMPOSITOR_CLIP_TRANSFORM_RECORDER_H_