cc/debug/debug_rect_history.h

// Copyright 2012 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 CC_DEBUG_DEBUG_RECT_HISTORY_H_
#define CC_DEBUG_DEBUG_RECT_HISTORY_H_

#include <vector>
#include "base/basictypes.h"
#include "base/memory/scoped_ptr.h"
#include "cc/layers/layer_lists.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/rect_f.h"

namespace cc {

class LayerImpl;
class LayerTreeDebugState;

// There are currently six types of debug rects:
//
// - Paint rects (update rects): regions of a layer that needed to be
// re-uploaded to the texture resource; in most cases implying that they had to
// be repainted, too.
//
// - Property-changed rects: enclosing bounds of layers that cause changes to
// the screen even if the layer did not change internally. (For example, if the
// layer's opacity or position changes.)
//
// - Surface damage rects: the aggregate damage on a target surface that is
// caused by all layers and surfaces that contribute to it. This includes (1)
// paint rects, (2) property- changed rects, and (3) newly exposed areas.
//
// - Screen space rects: this is the region the contents occupy in screen space.
//
// - Replica screen space rects: this is the region the replica's contents
// occupy in screen space.
//
// - Occluding rects: these are the regions that contribute to the occluded
// region.
//
// - Non-Occluding rects: these are the regions of composited layers that do not
//   contribute to the occluded region.
//
enum DebugRectType {
  PAINT_RECT_TYPE,
  PROPERTY_CHANGED_RECT_TYPE,
  SURFACE_DAMAGE_RECT_TYPE,
  SCREEN_SPACE_RECT_TYPE,
  REPLICA_SCREEN_SPACE_RECT_TYPE,
  OCCLUDING_RECT_TYPE,
  NONOCCLUDING_RECT_TYPE,
  TOUCH_EVENT_HANDLER_RECT_TYPE,
  WHEEL_EVENT_HANDLER_RECT_TYPE,
  NON_FAST_SCROLLABLE_RECT_TYPE,
  ANIMATION_BOUNDS_RECT_TYPE,
};

struct DebugRect {
  DebugRect(DebugRectType new_type, gfx::RectF new_rect)
      : type(new_type), rect(new_rect) {}

  DebugRectType type;
  gfx::RectF rect;
};

// This class maintains a history of rects of various types that can be used
// for debugging purposes. The overhead of collecting rects is performed only if
// the appropriate LayerTreeSettings are enabled.
class DebugRectHistory {
 public:
  static scoped_ptr<DebugRectHistory> Create();

  ~DebugRectHistory();

  // Note: Saving debug rects must happen before layers' change tracking is
  // reset.
  void SaveDebugRectsForCurrentFrame(
      LayerImpl* root_layer,
      const LayerImplList& render_surface_layer_list,
      const std::vector<gfx::Rect>& occluding_screen_space_rects,
      const std::vector<gfx::Rect>& non_occluding_screen_space_rects,
      const LayerTreeDebugState& debug_state);

  const std::vector<DebugRect>& debug_rects() { return debug_rects_; }

 private:
  DebugRectHistory();

  void SavePaintRects(LayerImpl* layer);
  void SavePropertyChangedRects(
      const LayerImplList& render_surface_layer_list);
  void SaveSurfaceDamageRects(
      const LayerImplList& render_surface_layer_list);
  void SaveScreenSpaceRects(
      const LayerImplList& render_surface_layer_list);
  void SaveOccludingRects(
      const std::vector<gfx::Rect>& occluding_screen_space_rects);
  void SaveNonOccludingRects(
      const std::vector<gfx::Rect>& non_occluding_screen_space_rects);
  void SaveTouchEventHandlerRects(LayerImpl* layer);
  void SaveTouchEventHandlerRectsCallback(LayerImpl* layer);
  void SaveWheelEventHandlerRects(LayerImpl* layer);
  void SaveWheelEventHandlerRectsCallback(LayerImpl* layer);
  void SaveNonFastScrollableRects(LayerImpl* layer);
  void SaveNonFastScrollableRectsCallback(LayerImpl* layer);
  void SaveLayerAnimationBoundsRects(
      const LayerImplList& render_surface_layer_list);

  std::vector<DebugRect> debug_rects_;

  DISALLOW_COPY_AND_ASSIGN(DebugRectHistory);
};

}  // namespace cc

#endif  // CC_DEBUG_DEBUG_RECT_HISTORY_H_