ui/compositor/clip_transform_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_CLIP_TRANSFORM_RECORDER_H_
   6 #define UI_COMPOSITOR_CLIP_TRANSFORM_RECORDER_H_
   7
   8 #include <vector>
   9
  10 #include "base/macros.h"
  11 #include "ui/compositor/compositor_export.h"
  12
  13 namespace cc {
  14 class DisplayItem;
  15 class DisplayItemList;
  16 }
  17
  18 namespace gfx {
  19 class Path;
  20 class Rect;
  21 class Transform;
  22 }
  23
  24 namespace ui {
  25 class PaintContext;
  26
  27 // A class to provide scoped clips and transforms of painting to a
  28 // DisplayItemList. The the clip/transform provided will be applied to any
  29 // DisplayItems added to the DisplayItemList while this object is alive. In
  30 // other words, any nested PaintRecorders or other ClipTransformRecorders will
  31 // be clipped/transformed.
  32 class COMPOSITOR_EXPORT ClipTransformRecorder {
  33  public:
  34   explicit ClipTransformRecorder(const PaintContext& context);
  35   ~ClipTransformRecorder();
  36
  37   void ClipRect(const gfx::Rect& clip_rect);
  38   void ClipPath(const gfx::Path& clip_path);
  39   void ClipPathWithAntiAliasing(const gfx::Path& clip_path);
  40   void Transform(const gfx::Transform& transform);
  41
  42  private:
  43   enum Closer {
  44     CLIP_RECT,
  45     CLIP_PATH,
  46     TRANSFORM,
  47   };
  48   const PaintContext& context_;
  49   // If someone needs to do more than this many operations with a single
  50   // ClipTransformRecorder then increase the size of the closers_ array.
  51   Closer closers_[4];
  52   size_t num_closers_;
  53
  54   DISALLOW_COPY_AND_ASSIGN(ClipTransformRecorder);
  55 };
  56
  57 }  // namespace ui
  58
  59 #endif  // UI_COMPOSITOR_CLIP_TRANSFORM_RECORDER_H_