text: /*
   * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   *           (C) 1999 Antti Koivisto (koivisto@kde.org)
   *           (C) 2006 Allan Sandfeld Jensen (kde@carewolf.com)
   *           (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
   * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc.
   *               All rights reserved.
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Library General Public
   * License as published by the Free Software Foundation; either
   * version 2 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Library General Public License for more details.
   *
   * You should have received a copy of the GNU Library General Public License
   * along with this library; see the file COPYING.LIB.  If not, write to
   * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   * Boston, MA 02110-1301, USA.
   *
   */
  
  #ifndef LayoutImage_h
  #define LayoutImage_h
  
  #include "core/CoreExport.h"
  #include "core/fetch/ResourceClient.h"
  #include "core/layout/LayoutImageResource.h"
  #include "core/layout/LayoutReplaced.h"
  
  namespace blink {
  
  class HTMLAreaElement;
  class HTMLMapElement;
  
  // LayoutImage is used to display any image type.
  //
  // There is 2 types of images:
  // * normal images, e.g. <image>, <picture>.
  // * content images with "content: url(path/to/image.png)".
  // We store the type inside  m_isGeneratedContent.
  //
  // The class is image type agnostic as it only manipulates decoded images.
  // See LayoutImageResource that holds this image.
  class CORE_EXPORT LayoutImage : public LayoutReplaced {
   public:
    // These are the paddings to use when displaying either alt text or an image.
    static const unsigned short paddingWidth = 4;
    static const unsigned short paddingHeight = 4;
  
    LayoutImage(Element*);
    ~LayoutImage() override;
  
    static LayoutImage* createAnonymous(Document*);
  
    void setImageResource(LayoutImageResource*);
  
    LayoutImageResource* imageResource() { return m_imageResource.get(); }
    const LayoutImageResource* imageResource() const {
      return m_imageResource.get();
    }
    ImageResourceContent* cachedImage() const {
      return m_imageResource ? m_imageResource->cachedImage() : 0;
    }
  
    HTMLMapElement* imageMap() const;
    void areaElementFocusChanged(HTMLAreaElement*);
  
    void setIsGeneratedContent(bool generated = true) {
      m_isGeneratedContent = generated;
    }
  
    bool isGeneratedContent() const { return m_isGeneratedContent; }
  
    inline void setImageDevicePixelRatio(float factor) {
      m_imageDevicePixelRatio = factor;
    }
    float imageDevicePixelRatio() const { return m_imageDevicePixelRatio; }
  
    void intrinsicSizeChanged() override {
      if (m_imageResource)
        imageChanged(m_imageResource->imagePtr());
    }
  
    const char* name() const override { return "LayoutImage"; }
  
   protected:
    bool needsPreferredWidthsRecalculation() const final;
    LayoutReplaced* embeddedReplacedContent() const final;
    void computeIntrinsicSizingInfo(IntrinsicSizingInfo&) const final;
  
    void imageChanged(WrappedImagePtr, const IntRect* = nullptr) override;
  
    void paint(const PaintInfo&, const LayoutPoint&) const final;
  
    bool isOfType(LayoutObjectType type) const override {
      return type == LayoutObjectLayoutImage || LayoutReplaced::isOfType(type);
    }
  
    void willBeDestroyed() override;
  
    void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
  
   private:
    bool isImage() const override { return true; }
  
    void paintReplaced(const PaintInfo&, const LayoutPoint&) const override;
  
    bool foregroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect,
                                           unsigned maxDepthToTest) const final;
    bool computeBackgroundIsKnownToBeObscured() const final;
  
    bool backgroundShouldAlwaysBeClipped() const override { return true; }
  
    LayoutUnit minimumReplacedHeight() const override;
  
    void imageNotifyFinished(ImageResourceContent*) final;
    bool nodeAtPoint(HitTestResult&,
                     const HitTestLocation& locationInContainer,
                     const LayoutPoint& accumulatedOffset,
                     HitTestAction) final;
  
    void invalidatePaintAndMarkForLayoutIfNeeded();
    void updateIntrinsicSizeIfNeeded(const LayoutSize&);
  
    // This member wraps the associated decoded image.
    //
    // This field is set using setImageResource above which can be called in
    // several ways:
    // * For normal images, from the network stack (ImageLoader) once we have
    // some image data.
    // * For generated content, the resource is loaded during style resolution
    // and thus is stored in ComputedStyle (see ContentData::image) that gets
    // propagated to the anonymous LayoutImage in LayoutObject::createObject.
    Persistent<LayoutImageResource> m_imageResource;
    bool m_didIncrementVisuallyNonEmptyPixelCount;
  
    // This field stores whether this image is generated with 'content'.
    bool m_isGeneratedContent;
    float m_imageDevicePixelRatio;
  };
  
  DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutImage, isLayoutImage());
  
  }  // namespace blink
  
  #endif  // LayoutImage_h
  