1 /*
   2  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   3  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
   4  * Copyright (C) 2003, 2006, 2007, 2015 Apple Inc. All rights reserved.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Library General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Library General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Library General Public License
  17  * along with this library; see the file COPYING.LIB.  If not, write to
  18  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  19  * Boston, MA 02110-1301, USA.
  20  *
  21  */
  22 
  23 #pragma once
  24 
  25 #include "FrameView.h"
  26 #include "RenderBoxModelObject.h"
  27 #include "RenderOverflow.h"
  28 #include "ScrollTypes.h"
  29 #include "ShapeOutsideInfo.h"
  30 
  31 namespace WebCore {
  32 
  33 class InlineElementBox;
  34 class RenderBlockFlow;
  35 class RenderBoxFragmentInfo;
  36 class RenderFragmentContainer;
  37 struct PaintInfo;
  38 
  39 enum SizeType { MainOrPreferredSize, MinSize, MaxSize };
  40 enum AvailableLogicalHeightType { ExcludeMarginBorderPadding, IncludeMarginBorderPadding };
  41 enum OverlayScrollbarSizeRelevancy { IgnoreOverlayScrollbarSize, IncludeOverlayScrollbarSize };
  42 
  43 enum ShouldComputePreferred { ComputeActual, ComputePreferred };
  44 
  45 class RenderBox : public RenderBoxModelObject {
  46     WTF_MAKE_ISO_ALLOCATED(RenderBox);
  47 public:
  48     virtual ~RenderBox();
  49 
  50     // hasAutoZIndex only returns true if the element is positioned or a flex-item since
  51     // position:static elements that are not flex-items get their z-index coerced to auto.
  52     bool requiresLayer() const override
  53     {
  54         return isDocumentElementRenderer() || isPositioned() || createsGroup() || hasClipPath() || hasOverflowClip()
  55             || hasTransformRelatedProperty() || hasHiddenBackface() || hasReflection() || style().specifiesColumns()
  56             || !style().hasAutoZIndex();
  57     }
  58 
  59     bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect) const final;
  60 
  61     // Returns false for the body renderer if its background is propagated to the root.
  62     bool paintsOwnBackground() const;
  63 
  64     LayoutUnit x() const { return m_frameRect.x(); }
  65     LayoutUnit y() const { return m_frameRect.y(); }
  66     LayoutUnit width() const { return m_frameRect.width(); }
  67     LayoutUnit height() const { return m_frameRect.height(); }
  68 
  69     // These represent your location relative to your container as a physical offset.
  70     // In layout related methods you almost always want the logical location (e.g. x() and y()).
  71     LayoutUnit top() const { return topLeftLocation().y(); }
  72     LayoutUnit left() const { return topLeftLocation().x(); }
  73 
  74     void setX(LayoutUnit x) { m_frameRect.setX(x); }
  75     void setY(LayoutUnit y) { m_frameRect.setY(y); }
  76     void setWidth(LayoutUnit width) { m_frameRect.setWidth(width); }
  77     void setHeight(LayoutUnit height) { m_frameRect.setHeight(height); }
  78 
  79     LayoutUnit logicalLeft() const { return style().isHorizontalWritingMode() ? x() : y(); }
  80     LayoutUnit logicalRight() const { return logicalLeft() + logicalWidth(); }
  81     LayoutUnit logicalTop() const { return style().isHorizontalWritingMode() ? y() : x(); }
  82     LayoutUnit logicalBottom() const { return logicalTop() + logicalHeight(); }
  83     LayoutUnit logicalWidth() const { return style().isHorizontalWritingMode() ? width() : height(); }
  84     LayoutUnit logicalHeight() const { return style().isHorizontalWritingMode() ? height() : width(); }
  85 
  86     LayoutUnit constrainLogicalWidthInFragmentByMinMax(LayoutUnit, LayoutUnit, RenderBlock&, RenderFragmentContainer* = nullptr) const;
  87     LayoutUnit constrainLogicalHeightByMinMax(LayoutUnit logicalHeight, std::optional<LayoutUnit> intrinsicContentHeight) const;
  88     LayoutUnit constrainContentBoxLogicalHeightByMinMax(LayoutUnit logicalHeight, std::optional<LayoutUnit> intrinsicContentHeight) const;
  89 
  90     void setLogicalLeft(LayoutUnit left)
  91     {
  92         if (style().isHorizontalWritingMode())
  93             setX(left);
  94         else
  95             setY(left);
  96     }
  97     void setLogicalTop(LayoutUnit top)
  98     {
  99         if (style().isHorizontalWritingMode())
 100             setY(top);
 101         else
 102             setX(top);
 103     }
 104     void setLogicalLocation(const LayoutPoint& location)
 105     {
 106         if (style().isHorizontalWritingMode())
 107             setLocation(location);
 108         else
 109             setLocation(location.transposedPoint());
 110     }
 111     void setLogicalWidth(LayoutUnit size)
 112     {
 113         if (style().isHorizontalWritingMode())
 114             setWidth(size);
 115         else
 116             setHeight(size);
 117     }
 118     void setLogicalHeight(LayoutUnit size)
 119     {
 120         if (style().isHorizontalWritingMode())
 121             setHeight(size);
 122         else
 123             setWidth(size);
 124     }
 125     void setLogicalSize(const LayoutSize& size)
 126     {
 127         if (style().isHorizontalWritingMode())
 128             setSize(size);
 129         else
 130             setSize(size.transposedSize());
 131     }
 132 
 133     LayoutPoint location() const { return m_frameRect.location(); }
 134     LayoutSize locationOffset() const { return LayoutSize(x(), y()); }
 135     LayoutSize size() const { return m_frameRect.size(); }
 136 
 137     void setLocation(const LayoutPoint& location) { m_frameRect.setLocation(location); }
 138 
 139     void setSize(const LayoutSize& size) { m_frameRect.setSize(size); }
 140     void move(LayoutUnit dx, LayoutUnit dy) { m_frameRect.move(dx, dy); }
 141 
 142     LayoutRect frameRect() const { return m_frameRect; }
 143     void setFrameRect(const LayoutRect& rect) { m_frameRect = rect; }
 144 
 145     LayoutRect marginBoxRect() const
 146     {
 147         LayoutRect box = borderBoxRect();
 148         box.expand(m_marginBox);
 149         return box;
 150     }
 151     LayoutRect borderBoxRect() const { return LayoutRect(LayoutPoint(), size()); }
 152     LayoutRect paddingBoxRect() const { return LayoutRect(borderLeft(), borderTop(), contentWidth() + paddingLeft() + paddingRight(), contentHeight() + paddingTop() + paddingBottom()); }
 153     LayoutRect borderBoundingBox() const final { return borderBoxRect(); }
 154 
 155     WEBCORE_EXPORT RoundedRect::Radii borderRadii() const;
 156 
 157     // The content area of the box (excludes padding - and intrinsic padding for table cells, etc... - and border).
 158     LayoutRect contentBoxRect() const;
 159     LayoutPoint contentBoxLocation() const;
 160 
 161     // The content box in absolute coords. Ignores transforms.
 162     IntRect absoluteContentBox() const;
 163     // The content box converted to absolute coords (taking transforms into account).
 164     WEBCORE_EXPORT FloatQuad absoluteContentQuad() const;
 165 
 166     // This returns the content area of the box (excluding padding and border). The only difference with contentBoxRect is that computedCSSContentBoxRect
 167     // does include the intrinsic padding in the content box as this is what some callers expect (like getComputedStyle).
 168     LayoutRect computedCSSContentBoxRect() const { return LayoutRect(borderLeft() + computedCSSPaddingLeft(), borderTop() + computedCSSPaddingTop(), clientWidth() - computedCSSPaddingLeft() - computedCSSPaddingRight(), clientHeight() - computedCSSPaddingTop() - computedCSSPaddingBottom()); }
 169 
 170     // Bounds of the outline box in absolute coords. Respects transforms
 171     LayoutRect outlineBoundsForRepaint(const RenderLayerModelObject* /*repaintContainer*/, const RenderGeometryMap*) const final;
 172     void addFocusRingRects(Vector<LayoutRect>&, const LayoutPoint& additionalOffset, const RenderLayerModelObject* paintContainer = nullptr) override;
 173 
 174     FloatRect repaintRectInLocalCoordinates() const override { return borderBoxRect(); }
 175     FloatRect objectBoundingBox() const override { return borderBoxRect(); }
 176 
 177     // Note these functions are not equivalent of childrenOfType<RenderBox>
 178     RenderBox* parentBox() const;
 179     RenderBox* firstChildBox() const;
 180     RenderBox* lastChildBox() const;
 181     RenderBox* previousSiblingBox() const;
 182     RenderBox* nextSiblingBox() const;
 183 
 184     // Visual and layout overflow are in the coordinate space of the box.  This means that they aren't purely physical directions.
 185     // For horizontal-tb and vertical-lr they will match physical directions, but for horizontal-bt and vertical-rl, the top/bottom and left/right
 186     // respectively are flipped when compared to their physical counterparts.  For example minX is on the left in vertical-lr,
 187     // but it is on the right in vertical-rl.
 188     WEBCORE_EXPORT LayoutRect flippedClientBoxRect() const;
 189     LayoutRect layoutOverflowRect() const { return m_overflow ? m_overflow->layoutOverflowRect() : flippedClientBoxRect(); }
 190     LayoutUnit logicalLeftLayoutOverflow() const { return style().isHorizontalWritingMode() ? layoutOverflowRect().x() : layoutOverflowRect().y(); }
 191     LayoutUnit logicalRightLayoutOverflow() const { return style().isHorizontalWritingMode() ? layoutOverflowRect().maxX() : layoutOverflowRect().maxY(); }
 192 
 193     virtual LayoutRect visualOverflowRect() const { return m_overflow ? m_overflow->visualOverflowRect() : borderBoxRect(); }
 194     LayoutUnit logicalLeftVisualOverflow() const { return style().isHorizontalWritingMode() ? visualOverflowRect().x() : visualOverflowRect().y(); }
 195     LayoutUnit logicalRightVisualOverflow() const { return style().isHorizontalWritingMode() ? visualOverflowRect().maxX() : visualOverflowRect().maxY(); }
 196 
 197     LayoutRect overflowRectForPaintRejection() const;
 198 
 199     void addLayoutOverflow(const LayoutRect&);
 200     void addVisualOverflow(const LayoutRect&);
 201     void clearOverflow();
 202 
 203     virtual bool isTopLayoutOverflowAllowed() const { return !style().isLeftToRightDirection() && !isHorizontalWritingMode(); }
 204     virtual bool isLeftLayoutOverflowAllowed() const { return !style().isLeftToRightDirection() && isHorizontalWritingMode(); }
 205 
 206     void addVisualEffectOverflow();
 207     LayoutRect applyVisualEffectOverflow(const LayoutRect&) const;
 208     void addOverflowFromChild(const RenderBox* child) { addOverflowFromChild(child, child->locationOffset()); }
 209     void addOverflowFromChild(const RenderBox* child, const LayoutSize& delta);
 210 
 211     void updateLayerTransform();
 212 
 213     LayoutSize contentSize() const { return { contentWidth(), contentHeight() }; }
 214     LayoutUnit contentWidth() const { return clientWidth() - paddingLeft() - paddingRight(); }
 215     LayoutUnit contentHeight() const { return clientHeight() - paddingTop() - paddingBottom(); }
 216     LayoutUnit contentLogicalWidth() const { return style().isHorizontalWritingMode() ? contentWidth() : contentHeight(); }
 217     LayoutUnit contentLogicalHeight() const { return style().isHorizontalWritingMode() ? contentHeight() : contentWidth(); }
 218 
 219     // IE extensions. Used to calculate offsetWidth/Height.  Overridden by inlines (RenderFlow)
 220     // to return the remaining width on a given line (and the height of a single line).
 221     LayoutUnit offsetWidth() const override { return width(); }
 222     LayoutUnit offsetHeight() const override { return height(); }
 223 
 224     // More IE extensions.  clientWidth and clientHeight represent the interior of an object
 225     // excluding border and scrollbar.  clientLeft/Top are just the borderLeftWidth and borderTopWidth.
 226     LayoutUnit clientLeft() const { return borderLeft(); }
 227     LayoutUnit clientTop() const { return borderTop(); }
 228     WEBCORE_EXPORT LayoutUnit clientWidth() const;
 229     WEBCORE_EXPORT LayoutUnit clientHeight() const;
 230     LayoutUnit clientLogicalWidth() const { return style().isHorizontalWritingMode() ? clientWidth() : clientHeight(); }
 231     LayoutUnit clientLogicalHeight() const { return style().isHorizontalWritingMode() ? clientHeight() : clientWidth(); }
 232     LayoutUnit clientLogicalBottom() const { return borderBefore() + clientLogicalHeight(); }
 233     LayoutRect clientBoxRect() const { return LayoutRect(clientLeft(), clientTop(), clientWidth(), clientHeight()); }
 234 
 235     // scrollWidth/scrollHeight will be the same as clientWidth/clientHeight unless the
 236     // object has overflow:hidden/scroll/auto specified and also has overflow.
 237     // scrollLeft/Top return the current scroll position.  These methods are virtual so that objects like
 238     // textareas can scroll shadow content (but pretend that they are the objects that are
 239     // scrolling).
 240     virtual int scrollLeft() const;
 241     virtual int scrollTop() const;
 242     virtual int scrollWidth() const;
 243     virtual int scrollHeight() const;
 244     virtual void setScrollLeft(int, ScrollClamping = ScrollClamping::Clamped);
 245     virtual void setScrollTop(int, ScrollClamping = ScrollClamping::Clamped);
 246 
 247     LayoutUnit marginTop() const override { return m_marginBox.top(); }
 248     LayoutUnit marginBottom() const override { return m_marginBox.bottom(); }
 249     LayoutUnit marginLeft() const override { return m_marginBox.left(); }
 250     LayoutUnit marginRight() const override { return m_marginBox.right(); }
 251     void setMarginTop(LayoutUnit margin) { m_marginBox.setTop(margin); }
 252     void setMarginBottom(LayoutUnit margin) { m_marginBox.setBottom(margin); }
 253     void setMarginLeft(LayoutUnit margin) { m_marginBox.setLeft(margin); }
 254     void setMarginRight(LayoutUnit margin) { m_marginBox.setRight(margin); }
 255 
 256     LayoutUnit marginLogicalLeft() const { return m_marginBox.start(style().writingMode()); }
 257     LayoutUnit marginLogicalRight() const { return m_marginBox.end(style().writingMode()); }
 258 
 259     LayoutUnit marginBefore(const RenderStyle* overrideStyle = nullptr) const final { return m_marginBox.before((overrideStyle ? overrideStyle : &style())->writingMode()); }
 260     LayoutUnit marginAfter(const RenderStyle* overrideStyle = nullptr) const final { return m_marginBox.after((overrideStyle ? overrideStyle : &style())->writingMode()); }
 261     LayoutUnit marginStart(const RenderStyle* overrideStyle = nullptr) const final
 262     {
 263         const RenderStyle* styleToUse = overrideStyle ? overrideStyle : &style();
 264         return m_marginBox.start(styleToUse->writingMode(), styleToUse->direction());
 265     }
 266     LayoutUnit marginEnd(const RenderStyle* overrideStyle = nullptr) const final
 267     {
 268         const RenderStyle* styleToUse = overrideStyle ? overrideStyle : &style();
 269         return m_marginBox.end(styleToUse->writingMode(), styleToUse->direction());
 270     }
 271     void setMarginBefore(LayoutUnit value, const RenderStyle* overrideStyle = nullptr) { m_marginBox.setBefore(value, (overrideStyle ? overrideStyle : &style())->writingMode()); }
 272     void setMarginAfter(LayoutUnit value, const RenderStyle* overrideStyle = nullptr) { m_marginBox.setAfter(value, (overrideStyle ? overrideStyle : &style())->writingMode()); }
 273     void setMarginStart(LayoutUnit value, const RenderStyle* overrideStyle = nullptr)
 274     {
 275         const RenderStyle* styleToUse = overrideStyle ? overrideStyle : &style();
 276         m_marginBox.setStart(value, styleToUse->writingMode(), styleToUse->direction());
 277     }
 278     void setMarginEnd(LayoutUnit value, const RenderStyle* overrideStyle = nullptr)
 279     {
 280         const RenderStyle* styleToUse = overrideStyle ? overrideStyle : &style();
 281         m_marginBox.setEnd(value, styleToUse->writingMode(), styleToUse->direction());
 282     }
 283 
 284     virtual bool isSelfCollapsingBlock() const { return false; }
 285     virtual LayoutUnit collapsedMarginBefore() const { return marginBefore(); }
 286     virtual LayoutUnit collapsedMarginAfter() const { return marginAfter(); }
 287 
 288     void absoluteRects(Vector<IntRect>&, const LayoutPoint& accumulatedOffset) const override;
 289     void absoluteQuads(Vector<FloatQuad>&, bool* wasFixed) const override;
 290 
 291     int reflectionOffset() const;
 292     // Given a rect in the object's coordinate space, returns the corresponding rect in the reflection.
 293     LayoutRect reflectedRect(const LayoutRect&) const;
 294 
 295     void layout() override;
 296     bool nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction) override;
 297 
 298     LayoutUnit minPreferredLogicalWidth() const override;
 299     LayoutUnit maxPreferredLogicalWidth() const override;
 300 
 301     // FIXME: We should rename these back to overrideLogicalHeight/Width and have them store
 302     // the border-box height/width like the regular height/width accessors on RenderBox.
 303     // Right now, these are different than contentHeight/contentWidth because they still
 304     // include the scrollbar height/width.
 305     LayoutUnit overrideLogicalContentWidth() const;
 306     LayoutUnit overrideLogicalContentHeight() const;
 307     bool hasOverrideLogicalContentHeight() const;
 308     bool hasOverrideLogicalContentWidth() const;
 309     void setOverrideLogicalContentHeight(LayoutUnit);
 310     void setOverrideLogicalContentWidth(LayoutUnit);
 311     void clearOverrideSize();
 312     void clearOverrideLogicalContentHeight();
 313     void clearOverrideLogicalContentWidth();
 314 
 315     std::optional<LayoutUnit> overrideContainingBlockContentLogicalWidth() const;
 316     std::optional<LayoutUnit> overrideContainingBlockContentLogicalHeight() const;
 317     bool hasOverrideContainingBlockLogicalWidth() const;
 318     bool hasOverrideContainingBlockLogicalHeight() const;
 319     void setOverrideContainingBlockContentLogicalWidth(std::optional<LayoutUnit>);
 320     void setOverrideContainingBlockContentLogicalHeight(std::optional<LayoutUnit>);
 321     void clearContainingBlockOverrideSize();
 322     void clearOverrideContainingBlockContentLogicalHeight();
 323 
 324     LayoutSize offsetFromContainer(RenderElement&, const LayoutPoint&, bool* offsetDependsOnPoint = nullptr) const override;
 325 
 326     LayoutUnit adjustBorderBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
 327     LayoutUnit adjustContentBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
 328 
 329     // Overridden by fieldsets to subtract out the intrinsic border.
 330     virtual LayoutUnit adjustBorderBoxLogicalHeightForBoxSizing(LayoutUnit height) const;
 331     virtual LayoutUnit adjustContentBoxLogicalHeightForBoxSizing(std::optional<LayoutUnit> height) const;
 332 
 333     struct ComputedMarginValues {
 334         LayoutUnit m_before;
 335         LayoutUnit m_after;
 336         LayoutUnit m_start;
 337         LayoutUnit m_end;
 338     };
 339     struct LogicalExtentComputedValues {
 340         LayoutUnit m_extent;
 341         LayoutUnit m_position;
 342         ComputedMarginValues m_margins;
 343     };
 344     // Resolve auto margins in the inline direction of the containing block so that objects can be pushed to the start, middle or end
 345     // of the containing block.
 346     void computeInlineDirectionMargins(const RenderBlock& containingBlock, LayoutUnit containerWidth, LayoutUnit childWidth, LayoutUnit& marginStart, LayoutUnit& marginEnd) const;
 347 
 348     // Used to resolve margins in the containing block's block-flow direction.
 349     void computeBlockDirectionMargins(const RenderBlock& containingBlock, LayoutUnit& marginBefore, LayoutUnit& marginAfter) const;
 350     void computeAndSetBlockDirectionMargins(const RenderBlock& containingBlock);
 351 
 352     enum RenderBoxFragmentInfoFlags { CacheRenderBoxFragmentInfo, DoNotCacheRenderBoxFragmentInfo };
 353     LayoutRect borderBoxRectInFragment(RenderFragmentContainer*, RenderBoxFragmentInfoFlags = CacheRenderBoxFragmentInfo) const;
 354     LayoutRect clientBoxRectInFragment(RenderFragmentContainer*) const;
 355     RenderFragmentContainer* clampToStartAndEndFragments(RenderFragmentContainer*) const;
 356     bool hasFragmentRangeInFragmentedFlow() const;
 357     virtual LayoutUnit offsetFromLogicalTopOfFirstPage() const;
 358 
 359     void positionLineBox(InlineElementBox&);
 360 
 361     virtual std::unique_ptr<InlineElementBox> createInlineBox();
 362     void dirtyLineBoxes(bool fullLayout);
 363 
 364     // For inline replaced elements, this function returns the inline box that owns us.  Enables
 365     // the replaced RenderObject to quickly determine what line it is contained on and to easily
 366     // iterate over structures on the line.
 367     InlineElementBox* inlineBoxWrapper() const { return m_inlineBoxWrapper; }
 368     void setInlineBoxWrapper(InlineElementBox*);
 369     void deleteLineBoxWrapper();
 370 
 371     LayoutRect clippedOverflowRectForRepaint(const RenderLayerModelObject* repaintContainer) const override;
 372     LayoutRect computeRectForRepaint(const LayoutRect&, const RenderLayerModelObject* repaintContainer, RepaintContext context = { false, false }) const override;
 373     void repaintDuringLayoutIfMoved(const LayoutRect&);
 374     virtual void repaintOverhangingFloats(bool paintAllDescendants);
 375 
 376     LayoutUnit containingBlockLogicalWidthForContent() const override;
 377     LayoutUnit containingBlockLogicalHeightForContent(AvailableLogicalHeightType) const;
 378 
 379     LayoutUnit containingBlockLogicalWidthForContentInFragment(RenderFragmentContainer*) const;
 380     LayoutUnit containingBlockAvailableLineWidthInFragment(RenderFragmentContainer*) const;
 381     LayoutUnit perpendicularContainingBlockLogicalHeight() const;
 382 
 383     virtual void updateLogicalWidth();
 384     virtual void updateLogicalHeight();
 385     virtual LogicalExtentComputedValues computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit logicalTop) const;
 386 
 387     void cacheIntrinsicContentLogicalHeightForFlexItem(LayoutUnit) const;
 388 
 389     // This function will compute the logical border-box height, without laying
 390     // out the box. This means that the result is only "correct" when the height
 391     // is explicitly specified. This function exists so that intrinsic width
 392     // calculations have a way to deal with children that have orthogonal writing modes.
 393     // When there is no explicit height, this function assumes a content height of
 394     // zero (and returns just border + padding).
 395     LayoutUnit computeLogicalHeightWithoutLayout() const;
 396 
 397     RenderBoxFragmentInfo* renderBoxFragmentInfo(RenderFragmentContainer*, RenderBoxFragmentInfoFlags = CacheRenderBoxFragmentInfo) const;
 398     void computeLogicalWidthInFragment(LogicalExtentComputedValues&, RenderFragmentContainer* = nullptr) const;
 399 
 400     bool stretchesToViewport() const
 401     {
 402         return document().inQuirksMode() && style().logicalHeight().isAuto() && !isFloatingOrOutOfFlowPositioned() && (isDocumentElementRenderer() || isBody()) && !isInline();
 403     }
 404 
 405     virtual LayoutSize intrinsicSize() const { return LayoutSize(); }
 406     LayoutUnit intrinsicLogicalWidth() const { return style().isHorizontalWritingMode() ? intrinsicSize().width() : intrinsicSize().height(); }
 407     LayoutUnit intrinsicLogicalHeight() const { return style().isHorizontalWritingMode() ? intrinsicSize().height() : intrinsicSize().width(); }
 408 
 409     // Whether or not the element shrinks to its intrinsic width (rather than filling the width
 410     // of a containing block).  HTML4 buttons, <select>s, <input>s, legends, and floating/compact elements do this.
 411     bool sizesLogicalWidthToFitContent(SizeType) const;
 412 
 413     bool hasStretchedLogicalWidth() const;
 414     bool isStretchingColumnFlexItem() const;
 415     bool columnFlexItemHasStretchAlignment() const;
 416 
 417     LayoutUnit shrinkLogicalWidthToAvoidFloats(LayoutUnit childMarginStart, LayoutUnit childMarginEnd, const RenderBlock& cb, RenderFragmentContainer*) const;
 418 
 419     LayoutUnit computeLogicalWidthInFragmentUsing(SizeType, Length logicalWidth, LayoutUnit availableLogicalWidth, const RenderBlock& containingBlock, RenderFragmentContainer*) const;
 420     std::optional<LayoutUnit> computeLogicalHeightUsing(SizeType, const Length& height, std::optional<LayoutUnit> intrinsicContentHeight) const;
 421     std::optional<LayoutUnit> computeContentLogicalHeight(SizeType, const Length& height, std::optional<LayoutUnit> intrinsicContentHeight) const;
 422     std::optional<LayoutUnit> computeContentAndScrollbarLogicalHeightUsing(SizeType, const Length& height, std::optional<LayoutUnit> intrinsicContentHeight) const;
 423     LayoutUnit computeReplacedLogicalWidthUsing(SizeType, Length width) const;
 424     LayoutUnit computeReplacedLogicalWidthRespectingMinMaxWidth(LayoutUnit logicalWidth, ShouldComputePreferred  = ComputeActual) const;
 425     LayoutUnit computeReplacedLogicalHeightUsing(SizeType, Length height) const;
 426     LayoutUnit computeReplacedLogicalHeightRespectingMinMaxHeight(LayoutUnit logicalHeight) const;
 427 
 428     virtual LayoutUnit computeReplacedLogicalWidth(ShouldComputePreferred  = ComputeActual) const;
 429     virtual LayoutUnit computeReplacedLogicalHeight(std::optional<LayoutUnit> estimatedUsedWidth = std::nullopt) const;
 430 
 431     std::optional<LayoutUnit> computePercentageLogicalHeight(const Length& height) const;
 432 
 433     virtual LayoutUnit availableLogicalWidth() const { return contentLogicalWidth(); }
 434     virtual LayoutUnit availableLogicalHeight(AvailableLogicalHeightType) const;
 435     LayoutUnit availableLogicalHeightUsing(const Length&, AvailableLogicalHeightType) const;
 436 
 437     // There are a few cases where we need to refer specifically to the available physical width and available physical height.
 438     // Relative positioning is one of those cases, since left/top offsets are physical.
 439     LayoutUnit availableWidth() const { return style().isHorizontalWritingMode() ? availableLogicalWidth() : availableLogicalHeight(IncludeMarginBorderPadding); }
 440     LayoutUnit availableHeight() const { return style().isHorizontalWritingMode() ? availableLogicalHeight(IncludeMarginBorderPadding) : availableLogicalWidth(); }
 441 
 442     virtual int verticalScrollbarWidth() const;
 443     int horizontalScrollbarHeight() const;
 444     int intrinsicScrollbarLogicalWidth() const;
 445     int scrollbarLogicalWidth() const { return style().isHorizontalWritingMode() ? verticalScrollbarWidth() : horizontalScrollbarHeight(); }
 446     int scrollbarLogicalHeight() const { return style().isHorizontalWritingMode() ? horizontalScrollbarHeight() : verticalScrollbarWidth(); }
 447     virtual bool scroll(ScrollDirection, ScrollGranularity, float multiplier = 1, Element** stopElement = nullptr, RenderBox* startBox = nullptr, const IntPoint& wheelEventAbsolutePoint = IntPoint());
 448     virtual bool logicalScroll(ScrollLogicalDirection, ScrollGranularity, float multiplier = 1, Element** stopElement = nullptr);
 449     WEBCORE_EXPORT bool canBeScrolledAndHasScrollableArea() const;
 450     virtual bool canBeProgramaticallyScrolled() const;
 451     virtual void autoscroll(const IntPoint&);
 452     bool canAutoscroll() const;
 453     IntSize calculateAutoscrollDirection(const IntPoint& windowPoint) const;
 454     static RenderBox* findAutoscrollable(RenderObject*);
 455     virtual void stopAutoscroll() { }
 456     virtual void panScroll(const IntPoint&);
 457 
 458     bool hasVerticalScrollbarWithAutoBehavior() const;
 459     bool hasHorizontalScrollbarWithAutoBehavior() const;
 460 
 461     bool scrollsOverflow() const { return scrollsOverflowX() || scrollsOverflowY(); }
 462     bool scrollsOverflowX() const { return hasOverflowClip() && (style().overflowX() == OSCROLL || hasHorizontalScrollbarWithAutoBehavior()); }
 463     bool scrollsOverflowY() const { return hasOverflowClip() && (style().overflowY() == OSCROLL || hasVerticalScrollbarWithAutoBehavior()); }
 464 
 465     bool hasHorizontalOverflow() const { return scrollWidth() != roundToInt(clientWidth()); }
 466     bool hasVerticalOverflow() const { return scrollHeight() != roundToInt(clientHeight()); }
 467 
 468     bool hasScrollableOverflowX() const { return scrollsOverflowX() && hasHorizontalOverflow(); }
 469     bool hasScrollableOverflowY() const { return scrollsOverflowY() && hasVerticalOverflow(); }
 470 
 471     bool usesCompositedScrolling() const;
 472 
 473     bool percentageLogicalHeightIsResolvable() const;
 474     bool hasUnsplittableScrollingOverflow() const;
 475     bool isUnsplittableForPagination() const;
 476 
 477     bool shouldTreatChildAsReplacedInTableCells() const;
 478 
 479     LayoutRect localCaretRect(InlineBox*, unsigned caretOffset, LayoutUnit* extraWidthToEndOfLine = nullptr) override;
 480 
 481     virtual LayoutRect overflowClipRect(const LayoutPoint& location, RenderFragmentContainer* = nullptr, OverlayScrollbarSizeRelevancy = IgnoreOverlayScrollbarSize, PaintPhase = PaintPhaseBlockBackground);
 482     virtual LayoutRect overflowClipRectForChildLayers(const LayoutPoint& location, RenderFragmentContainer* fragment, OverlayScrollbarSizeRelevancy relevancy) { return overflowClipRect(location, fragment, relevancy); }
 483     LayoutRect clipRect(const LayoutPoint& location, RenderFragmentContainer*);
 484     virtual bool hasControlClip() const { return false; }
 485     virtual LayoutRect controlClipRect(const LayoutPoint&) const { return LayoutRect(); }
 486     bool pushContentsClip(PaintInfo&, const LayoutPoint& accumulatedOffset);
 487     void popContentsClip(PaintInfo&, PaintPhase originalPhase, const LayoutPoint& accumulatedOffset);
 488 
 489     virtual void paintObject(PaintInfo&, const LayoutPoint&) { ASSERT_NOT_REACHED(); }
 490     virtual void paintBoxDecorations(PaintInfo&, const LayoutPoint&);
 491     virtual void paintMask(PaintInfo&, const LayoutPoint&);
 492     virtual void paintClippingMask(PaintInfo&, const LayoutPoint&);
 493     void imageChanged(WrappedImagePtr, const IntRect* = nullptr) override;
 494 
 495     // Called when a positioned object moves but doesn't necessarily change size.  A simplified layout is attempted
 496     // that just updates the object's position. If the size does change, the object remains dirty.
 497     bool tryLayoutDoingPositionedMovementOnly()
 498     {
 499         LayoutUnit oldWidth = width();
 500         updateLogicalWidth();
 501         // If we shrink to fit our width may have changed, so we still need full layout.
 502         if (oldWidth != width())
 503             return false;
 504         updateLogicalHeight();
 505         return true;
 506     }
 507 
 508     LayoutRect maskClipRect(const LayoutPoint& paintOffset);
 509 
 510     VisiblePosition positionForPoint(const LayoutPoint&, const RenderFragmentContainer*) override;
 511 
 512     void removeFloatingOrPositionedChildFromBlockLists();
 513 
 514     RenderLayer* enclosingFloatPaintingLayer() const;
 515 
 516     virtual std::optional<int> firstLineBaseline() const { return std::optional<int>(); }
 517     virtual std::optional<int> inlineBlockBaseline(LineDirectionMode) const { return std::optional<int>(); } // Returns empty if we should skip this box when computing the baseline of an inline-block.
 518 
 519     bool shrinkToAvoidFloats() const;
 520     virtual bool avoidsFloats() const;
 521 
 522     virtual void markForPaginationRelayoutIfNeeded() { }
 523 
 524     bool isWritingModeRoot() const { return !parent() || parent()->style().writingMode() != style().writingMode(); }
 525 
 526     bool isDeprecatedFlexItem() const { return !isInline() && !isFloatingOrOutOfFlowPositioned() && parent() && parent()->isDeprecatedFlexibleBox(); }
 527     bool isFlexItemIncludingDeprecated() const { return !isInline() && !isFloatingOrOutOfFlowPositioned() && parent() && parent()->isFlexibleBoxIncludingDeprecated(); }
 528 
 529     LayoutUnit lineHeight(bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
 530     int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
 531 
 532     LayoutUnit offsetLeft() const override;
 533     LayoutUnit offsetTop() const override;
 534 
 535     LayoutPoint flipForWritingModeForChild(const RenderBox* child, const LayoutPoint&) const;
 536     LayoutUnit flipForWritingMode(LayoutUnit position) const; // The offset is in the block direction (y for horizontal writing modes, x for vertical writing modes).
 537     LayoutPoint flipForWritingMode(const LayoutPoint&) const;
 538     LayoutSize flipForWritingMode(const LayoutSize&) const;
 539     void flipForWritingMode(LayoutRect&) const;
 540     FloatPoint flipForWritingMode(const FloatPoint&) const;
 541     void flipForWritingMode(FloatRect&) const;
 542     // These represent your location relative to your container as a physical offset.
 543     // In layout related methods you almost always want the logical location (e.g. x() and y()).
 544     LayoutPoint topLeftLocation() const;
 545     LayoutSize topLeftLocationOffset() const;
 546     void applyTopLeftLocationOffset(LayoutPoint& point) const
 547     {
 548         // This is inlined for speed, since it is used by updateLayerPosition() during scrolling.
 549         if (!document().view()->hasFlippedBlockRenderers())
 550             point.move(m_frameRect.x(), m_frameRect.y());
 551         else
 552             applyTopLeftLocationOffsetWithFlipping(point);
 553     }
 554 
 555     LayoutRect logicalVisualOverflowRectForPropagation(const RenderStyle*) const;
 556     LayoutRect visualOverflowRectForPropagation(const RenderStyle*) const;
 557     LayoutRect logicalLayoutOverflowRectForPropagation(const RenderStyle*) const;
 558     LayoutRect layoutOverflowRectForPropagation(const RenderStyle*) const;
 559 
 560     bool hasRenderOverflow() const { return m_overflow; }
 561     bool hasVisualOverflow() const { return m_overflow && !borderBoxRect().contains(m_overflow->visualOverflowRect()); }
 562 
 563     virtual bool needsPreferredWidthsRecalculation() const;
 564     virtual void computeIntrinsicRatioInformation(FloatSize& /* intrinsicSize */, double& /* intrinsicRatio */) const { }
 565 
 566     ScrollPosition scrollPosition() const;
 567     LayoutSize cachedSizeForOverflowClip() const;
 568 
 569     bool shouldApplyClipAndScrollPositionForRepaint(const RenderLayerModelObject* repaintContainer) const;
 570     void applyCachedClipAndScrollPositionForRepaint(LayoutRect& paintRect) const;
 571 
 572     virtual bool hasRelativeDimensions() const;
 573     virtual bool hasRelativeLogicalHeight() const;
 574     virtual bool hasRelativeLogicalWidth() const;
 575 
 576     bool hasHorizontalLayoutOverflow() const
 577     {
 578         if (!m_overflow)
 579             return false;
 580 
 581         LayoutRect layoutOverflowRect = m_overflow->layoutOverflowRect();
 582         flipForWritingMode(layoutOverflowRect);
 583         return layoutOverflowRect.x() < x() || layoutOverflowRect.maxX() > x() + logicalWidth();
 584     }
 585 
 586     bool hasVerticalLayoutOverflow() const
 587     {
 588         if (!m_overflow)
 589             return false;
 590 
 591         LayoutRect layoutOverflowRect = m_overflow->layoutOverflowRect();
 592         flipForWritingMode(layoutOverflowRect);
 593         return layoutOverflowRect.y() < y() || layoutOverflowRect.maxY() > y() + logicalHeight();
 594     }
 595 
 596     virtual RenderPtr<RenderBox> createAnonymousBoxWithSameTypeAs(const RenderBox&) const
 597     {
 598         ASSERT_NOT_REACHED();
 599         return nullptr;
 600     }
 601 
 602     ShapeOutsideInfo* shapeOutsideInfo() const
 603     {
 604         return ShapeOutsideInfo::isEnabledFor(*this) ? ShapeOutsideInfo::info(*this) : nullptr;
 605     }
 606 
 607     void markShapeOutsideDependentsForLayout()
 608     {
 609         if (isFloating())
 610             removeFloatingOrPositionedChildFromBlockLists();
 611     }
 612 
 613     // True if this box can have a range in an outside fragmentation context.
 614     bool canHaveOutsideFragmentRange() const { return !isInFlowRenderFragmentedFlow(); }
 615     virtual bool needsLayoutAfterFragmentRangeChange() const { return false; }
 616 
 617     const RenderBox* findEnclosingScrollableContainer() const;
 618 
 619     bool isGridItem() const { return parent() && parent()->isRenderGrid() && !isExcludedFromNormalLayout(); }
 620     bool isFlexItem() const { return parent() && parent()->isFlexibleBox() && !isExcludedFromNormalLayout(); }
 621 
 622     virtual void adjustBorderBoxRectForPainting(LayoutRect&) { };
 623 
 624 protected:
 625     RenderBox(Element&, RenderStyle&&, BaseTypeFlags);
 626     RenderBox(Document&, RenderStyle&&, BaseTypeFlags);
 627 
 628     void styleWillChange(StyleDifference, const RenderStyle& newStyle) override;
 629     void styleDidChange(StyleDifference, const RenderStyle* oldStyle) override;
 630     void updateFromStyle() override;
 631 
 632     void willBeDestroyed() override;
 633 
 634     bool createsNewFormattingContext() const;
 635 
 636     virtual ItemPosition selfAlignmentNormalBehavior(const RenderBox* = nullptr) const { return ItemPositionStretch; }
 637 
 638     // Returns false if it could not cheaply compute the extent (e.g. fixed background), in which case the returned rect may be incorrect.
 639     bool getBackgroundPaintedExtent(const LayoutPoint& paintOffset, LayoutRect&) const;
 640     virtual bool foregroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect, unsigned maxDepthToTest) const;
 641     bool computeBackgroundIsKnownToBeObscured(const LayoutPoint& paintOffset) override;
 642 
 643     void paintBackground(const PaintInfo&, const LayoutRect&, BackgroundBleedAvoidance = BackgroundBleedNone);
 644 
 645     void paintFillLayer(const PaintInfo&, const Color&, const FillLayer&, const LayoutRect&, BackgroundBleedAvoidance, CompositeOperator, RenderElement* backgroundObject, BaseBackgroundColorUsage = BaseBackgroundColorUse);
 646     void paintFillLayers(const PaintInfo&, const Color&, const FillLayer&, const LayoutRect&, BackgroundBleedAvoidance = BackgroundBleedNone, CompositeOperator = CompositeSourceOver, RenderElement* backgroundObject = nullptr);
 647 
 648     void paintMaskImages(const PaintInfo&, const LayoutRect&);
 649 
 650     BackgroundBleedAvoidance determineBackgroundBleedAvoidance(GraphicsContext&) const;
 651     bool backgroundHasOpaqueTopLayer() const;
 652 
 653     void computePositionedLogicalWidth(LogicalExtentComputedValues&, RenderFragmentContainer* = nullptr) const;
 654 
 655     LayoutUnit computeIntrinsicLogicalWidthUsing(Length logicalWidthLength, LayoutUnit availableLogicalWidth, LayoutUnit borderAndPadding) const;
 656     virtual std::optional<LayoutUnit> computeIntrinsicLogicalContentHeightUsing(Length logicalHeightLength, std::optional<LayoutUnit> intrinsicContentHeight, LayoutUnit borderAndPadding) const;
 657 
 658     virtual bool shouldComputeSizeAsReplaced() const { return isReplaced() && !isInlineBlockOrInlineTable(); }
 659 
 660     void mapLocalToContainer(const RenderLayerModelObject* repaintContainer, TransformState&, MapCoordinatesFlags, bool* wasFixed) const override;
 661     const RenderObject* pushMappingToContainer(const RenderLayerModelObject*, RenderGeometryMap&) const override;
 662     void mapAbsoluteToLocalPoint(MapCoordinatesFlags, TransformState&) const override;
 663 
 664     void paintRootBoxFillLayers(const PaintInfo&);
 665 
 666     bool skipContainingBlockForPercentHeightCalculation(const RenderBox& containingBlock, bool isPerpendicularWritingMode) const;
 667 
 668 private:
 669     bool replacedMinMaxLogicalHeightComputesAsNone(SizeType) const;
 670 
 671     void updateShapeOutsideInfoAfterStyleChange(const RenderStyle&, const RenderStyle* oldStyle);
 672 
 673     void updateGridPositionAfterStyleChange(const RenderStyle&, const RenderStyle* oldStyle);
 674 
 675     bool scrollLayer(ScrollDirection, ScrollGranularity, float multiplier, Element** stopElement);
 676 
 677     bool fixedElementLaysOutRelativeToFrame(const FrameView&) const;
 678 
 679     bool includeVerticalScrollbarSize() const;
 680     bool includeHorizontalScrollbarSize() const;
 681 
 682     bool isScrollableOrRubberbandableBox() const override;
 683 
 684     // Returns true if we did a full repaint.
 685     bool repaintLayerRectsForImage(WrappedImagePtr, const FillLayer& layers, bool drawingBackground);
 686 
 687     LayoutUnit containingBlockLogicalWidthForPositioned(const RenderBoxModelObject& containingBlock, RenderFragmentContainer* = nullptr, bool checkForPerpendicularWritingMode = true) const;
 688     LayoutUnit containingBlockLogicalHeightForPositioned(const RenderBoxModelObject& containingBlock, bool checkForPerpendicularWritingMode = true) const;
 689 
 690     void computePositionedLogicalHeight(LogicalExtentComputedValues&) const;
 691     void computePositionedLogicalWidthUsing(SizeType, Length logicalWidth, const RenderBoxModelObject& containerBlock, TextDirection containerDirection,
 692                                             LayoutUnit containerLogicalWidth, LayoutUnit bordersPlusPadding,
 693                                             Length logicalLeft, Length logicalRight, Length marginLogicalLeft, Length marginLogicalRight,
 694                                             LogicalExtentComputedValues&) const;
 695     void computePositionedLogicalHeightUsing(SizeType, Length logicalHeightLength, const RenderBoxModelObject& containerBlock,
 696                                              LayoutUnit containerLogicalHeight, LayoutUnit bordersPlusPadding, LayoutUnit logicalHeight,
 697                                              Length logicalTop, Length logicalBottom, Length marginLogicalTop, Length marginLogicalBottom,
 698                                              LogicalExtentComputedValues&) const;
 699 
 700     void computePositionedLogicalHeightReplaced(LogicalExtentComputedValues&) const;
 701     void computePositionedLogicalWidthReplaced(LogicalExtentComputedValues&) const;
 702 
 703     LayoutUnit fillAvailableMeasure(LayoutUnit availableLogicalWidth) const;
 704     LayoutUnit fillAvailableMeasure(LayoutUnit availableLogicalWidth, LayoutUnit& marginStart, LayoutUnit& marginEnd) const;
 705 
 706     virtual void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const;
 707 
 708     // This function calculates the minimum and maximum preferred widths for an object.
 709     // These values are used in shrink-to-fit layout systems.
 710     // These include tables, positioned objects, floats and flexible boxes.
 711     virtual void computePreferredLogicalWidths() { setPreferredLogicalWidthsDirty(false); }
 712 
 713     LayoutRect frameRectForStickyPositioning() const final { return frameRect(); }
 714 
 715     void applyTopLeftLocationOffsetWithFlipping(LayoutPoint&) const;
 716 
 717 private:
 718     // The width/height of the contents + borders + padding.  The x/y location is relative to our container (which is not always our parent).
 719     LayoutRect m_frameRect;
 720 
 721 protected:
 722     LayoutBoxExtent m_marginBox;
 723 
 724     // The preferred logical width of the element if it were to break its lines at every possible opportunity.
 725     LayoutUnit m_minPreferredLogicalWidth;
 726 
 727     // The preferred logical width of the element if it never breaks any lines at all.
 728     LayoutUnit m_maxPreferredLogicalWidth;
 729 
 730     // For inline replaced elements, the inline box that owns us.
 731     InlineElementBox* m_inlineBoxWrapper { nullptr };
 732 
 733     // Our overflow information.
 734     RefPtr<RenderOverflow> m_overflow;
 735 
 736 private:
 737     // Used to store state between styleWillChange and styleDidChange
 738     static bool s_hadOverflowClip;
 739 };
 740 
 741 inline RenderBox* RenderBox::parentBox() const
 742 {
 743     if (is<RenderBox>(parent()))
 744         return downcast<RenderBox>(parent());
 745 
 746     ASSERT(!parent());
 747     return nullptr;
 748 }
 749 
 750 inline RenderBox* RenderBox::firstChildBox() const
 751 {
 752     if (is<RenderBox>(firstChild()))
 753         return downcast<RenderBox>(firstChild());
 754 
 755     ASSERT(!firstChild());
 756     return nullptr;
 757 }
 758 
 759 inline RenderBox* RenderBox::lastChildBox() const
 760 {
 761     if (is<RenderBox>(lastChild()))
 762         return downcast<RenderBox>(lastChild());
 763 
 764     ASSERT(!lastChild());
 765     return nullptr;
 766 }
 767 
 768 inline RenderBox* RenderBox::previousSiblingBox() const
 769 {
 770     if (is<RenderBox>(previousSibling()))
 771         return downcast<RenderBox>(previousSibling());
 772 
 773     ASSERT(!previousSibling());
 774     return nullptr;
 775 }
 776 
 777 inline RenderBox* RenderBox::nextSiblingBox() const
 778 {
 779     if (is<RenderBox>(nextSibling()))
 780         return downcast<RenderBox>(nextSibling());
 781 
 782     ASSERT(!nextSibling());
 783     return nullptr;
 784 }
 785 
 786 inline void RenderBox::setInlineBoxWrapper(InlineElementBox* boxWrapper)
 787 {
 788     if (boxWrapper) {
 789         ASSERT(!m_inlineBoxWrapper);
 790         // m_inlineBoxWrapper should already be 0. Deleting it is a safeguard against security issues.
 791         // Otherwise, there will two line box wrappers keeping the reference to this renderer, and
 792         // only one will be notified when the renderer is getting destroyed. The second line box wrapper
 793         // will keep a stale reference.
 794         if (UNLIKELY(m_inlineBoxWrapper != nullptr))
 795             deleteLineBoxWrapper();
 796     }
 797 
 798     m_inlineBoxWrapper = boxWrapper;
 799 }
 800 
 801 } // namespace WebCore
 802 
 803 SPECIALIZE_TYPE_TRAITS_RENDER_OBJECT(RenderBox, isBox())