third_party/WebKit/Source/platform/graphics/paint/FilterDisplayItem.h

// Copyright 2014 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 FilterDisplayItem_h
#define FilterDisplayItem_h

#include "platform/geometry/FloatRect.h"
#include "platform/graphics/CompositorFilterOperations.h"
#include "platform/graphics/paint/DisplayItem.h"
#include "wtf/PassRefPtr.h"
#ifndef NDEBUG
#include "wtf/text/WTFString.h"
#endif
#include <memory>

namespace blink {

class PLATFORM_EXPORT BeginFilterDisplayItem final
    : public PairedBeginDisplayItem {
 public:
  BeginFilterDisplayItem(const DisplayItemClient& client,
                         sk_sp<SkImageFilter> imageFilter,
                         const FloatRect& bounds,
                         const FloatPoint& origin,
                         CompositorFilterOperations filterOperations)
      : PairedBeginDisplayItem(client, kBeginFilter, sizeof(*this)),
        m_imageFilter(std::move(imageFilter)),
        m_compositorFilterOperations(std::move(filterOperations)),
        m_bounds(bounds),
        m_origin(origin) {}

  void replay(GraphicsContext&) const override;
  void appendToWebDisplayItemList(const IntRect&,
                                  WebDisplayItemList*) const override;
  bool drawsContent() const override;

 private:
#ifndef NDEBUG
  void dumpPropertiesAsDebugString(WTF::StringBuilder&) const override;
#endif
  bool equals(const DisplayItem& other) const final {
    // TODO(wangxianzhu): compare m_imageFilter and m_webFilterOperations.
    const auto& other_display_item =
        static_cast<const BeginFilterDisplayItem&>(other);
    return DisplayItem::equals(other) &&
           m_bounds == other_display_item.m_bounds &&
           m_origin == other_display_item.m_origin;
  }

  // FIXME: m_imageFilter should be replaced with m_webFilterOperations when
  // copying data to the compositor.
  sk_sp<SkImageFilter> m_imageFilter;
  CompositorFilterOperations m_compositorFilterOperations;
  const FloatRect m_bounds;
  const FloatPoint m_origin;
};

class PLATFORM_EXPORT EndFilterDisplayItem final : public PairedEndDisplayItem {
 public:
  EndFilterDisplayItem(const DisplayItemClient& client)
      : PairedEndDisplayItem(client, kEndFilter, sizeof(*this)) {}

  void replay(GraphicsContext&) const override;
  void appendToWebDisplayItemList(const IntRect&,
                                  WebDisplayItemList*) const override;

 private:
#if ENABLE(ASSERT)
  bool isEndAndPairedWith(DisplayItem::Type otherType) const final {
    return otherType == kBeginFilter;
  }
#endif
};

}  // namespace blink

#endif  // FilterDisplayItem_h