2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 * (C) 1999 Antti Koivisto (koivisto@kde.org)
4 * (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
5 * (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
6 * Copyright (C) 2005-2010, 2015 Apple Inc. All rights reserved.
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public License
19 * along with this library; see the file COPYING.LIB. If not, write to
20 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
26 #include "RenderBox.h"
28 #include "CSSFontSelector.h"
30 #include "ChromeClient.h"
32 #include "EventHandler.h"
33 #include "FloatQuad.h"
34 #include "FloatRoundedRect.h"
36 #include "FrameView.h"
37 #include "GraphicsContext.h"
38 #include "HTMLAnchorElement.h"
39 #include "HTMLBodyElement.h"
40 #include "HTMLButtonElement.h"
41 #include "HTMLFrameOwnerElement.h"
42 #include "HTMLHtmlElement.h"
43 #include "HTMLInputElement.h"
44 #include "HTMLLegendElement.h"
45 #include "HTMLNames.h"
46 #include "HTMLSelectElement.h"
47 #include "HTMLTextAreaElement.h"
48 #include "HitTestResult.h"
49 #include "InlineElementBox.h"
50 #include "MainFrame.h"
52 #include "PaintInfo.h"
53 #include "RenderBoxRegionInfo.h"
54 #include "RenderChildIterator.h"
55 #include "RenderDeprecatedFlexibleBox.h"
56 #include "RenderFlexibleBox.h"
57 #include "RenderGeometryMap.h"
58 #include "RenderInline.h"
59 #include "RenderIterator.h"
60 #include "RenderLayer.h"
61 #include "RenderLayerCompositor.h"
62 #include "RenderNamedFlowFragment.h"
63 #include "RenderNamedFlowThread.h"
64 #include "RenderTableCell.h"
65 #include "RenderTheme.h"
66 #include "RenderView.h"
67 #include "ScrollAnimator.h"
68 #include "ScrollbarTheme.h"
69 #include "TransformState.h"
70 #include "htmlediting.h"
73 #include <wtf/StackStats.h>
81 struct SameSizeAsRenderBox : public RenderBoxModelObject {
82 virtual ~SameSizeAsRenderBox() { }
84 LayoutBoxExtent marginBox;
85 LayoutUnit preferredLogicalWidths[2];
89 COMPILE_ASSERT(sizeof(RenderBox) == sizeof(SameSizeAsRenderBox), RenderBox_should_stay_small);
91 using namespace HTMLNames;
93 // Used by flexible boxes when flexing this element and by table cells.
94 typedef WTF::HashMap<const RenderBox*, LayoutUnit> OverrideSizeMap;
95 static OverrideSizeMap* gOverrideHeightMap = nullptr;
96 static OverrideSizeMap* gOverrideWidthMap = nullptr;
98 #if ENABLE(CSS_GRID_LAYOUT)
99 // Used by grid elements to properly size their grid items.
100 typedef WTF::HashMap<const RenderBox*, Optional<LayoutUnit>> OverrideOptionalSizeMap;
101 static OverrideOptionalSizeMap* gOverrideContainingBlockLogicalHeightMap = nullptr;
102 static OverrideOptionalSizeMap* gOverrideContainingBlockLogicalWidthMap = nullptr;
103 static OverrideSizeMap* gExtraInlineOffsetMap = nullptr;
104 static OverrideSizeMap* gExtraBlockOffsetMap = nullptr;
107 // Size of border belt for autoscroll. When mouse pointer in border belt,
108 // autoscroll is started.
109 static const int autoscrollBeltSize = 20;
110 static const unsigned backgroundObscurationTestMaxDepth = 4;
112 bool RenderBox::s_hadOverflowClip = false;
114 static bool skipBodyBackground(const RenderBox* bodyElementRenderer)
116 ASSERT(bodyElementRenderer->isBody());
117 // The <body> only paints its background if the root element has defined a background independent of the body,
118 // or if the <body>'s parent is not the document element's renderer (e.g. inside SVG foreignObject).
119 auto documentElementRenderer = bodyElementRenderer->document().documentElement()->renderer();
120 return documentElementRenderer
121 && !documentElementRenderer->hasBackground()
122 && (documentElementRenderer == bodyElementRenderer->parent());
125 RenderBox::RenderBox(Element& element, RenderStyle&& style, BaseTypeFlags baseTypeFlags)
126 : RenderBoxModelObject(element, WTFMove(style), baseTypeFlags)
127 , m_minPreferredLogicalWidth(-1)
128 , m_maxPreferredLogicalWidth(-1)
129 , m_inlineBoxWrapper(nullptr)
134 RenderBox::RenderBox(Document& document, RenderStyle&& style, BaseTypeFlags baseTypeFlags)
135 : RenderBoxModelObject(document, WTFMove(style), baseTypeFlags)
136 , m_minPreferredLogicalWidth(-1)
137 , m_maxPreferredLogicalWidth(-1)
138 , m_inlineBoxWrapper(nullptr)
143 RenderBox::~RenderBox()
145 if (frame().eventHandler().autoscrollRenderer() == this)
146 frame().eventHandler().stopAutoscrollTimer(true);
149 #if ENABLE(CSS_GRID_LAYOUT)
150 clearContainingBlockOverrideSize();
151 clearExtraInlineAndBlockOffests();
154 RenderBlock::removePercentHeightDescendantIfNeeded(*this);
156 #if ENABLE(CSS_SHAPES)
157 ShapeOutsideInfo::removeInfo(*this);
160 view().unscheduleLazyRepaint(*this);
161 if (hasControlStatesForRenderer(this))
162 removeControlStatesForRenderer(this);
165 RenderRegion* RenderBox::clampToStartAndEndRegions(RenderRegion* region) const
167 RenderFlowThread* flowThread = flowThreadContainingBlock();
169 ASSERT(isRenderView() || (region && flowThread));
173 // We need to clamp to the block, since we want any lines or blocks that overflow out of the
174 // logical top or logical bottom of the block to size as though the border box in the first and
175 // last regions extended infinitely. Otherwise the lines are going to size according to the regions
176 // they overflow into, which makes no sense when this block doesn't exist in |region| at all.
177 RenderRegion* startRegion = nullptr;
178 RenderRegion* endRegion = nullptr;
179 if (!flowThread->getRegionRangeForBox(this, startRegion, endRegion))
182 if (region->logicalTopForFlowThreadContent() < startRegion->logicalTopForFlowThreadContent())
184 if (region->logicalTopForFlowThreadContent() > endRegion->logicalTopForFlowThreadContent())
190 bool RenderBox::hasRegionRangeInFlowThread() const
192 RenderFlowThread* flowThread = flowThreadContainingBlock();
193 if (!flowThread || !flowThread->hasValidRegionInfo())
196 return flowThread->hasCachedRegionRangeForBox(this);
199 LayoutRect RenderBox::clientBoxRectInRegion(RenderRegion* region) const
202 return clientBoxRect();
204 LayoutRect clientBox = borderBoxRectInRegion(region);
205 clientBox.setLocation(clientBox.location() + LayoutSize(borderLeft(), borderTop()));
206 clientBox.setSize(clientBox.size() - LayoutSize(borderLeft() + borderRight() + verticalScrollbarWidth(), borderTop() + borderBottom() + horizontalScrollbarHeight()));
211 LayoutRect RenderBox::borderBoxRectInRegion(RenderRegion* region, RenderBoxRegionInfoFlags cacheFlag) const
214 return borderBoxRect();
216 RenderFlowThread* flowThread = flowThreadContainingBlock();
218 return borderBoxRect();
220 RenderRegion* startRegion = nullptr;
221 RenderRegion* endRegion = nullptr;
222 if (!flowThread->getRegionRangeForBox(this, startRegion, endRegion)) {
223 // FIXME: In a perfect world this condition should never happen.
224 return borderBoxRect();
227 ASSERT(flowThread->regionInRange(region, startRegion, endRegion));
229 // Compute the logical width and placement in this region.
230 RenderBoxRegionInfo* boxInfo = renderBoxRegionInfo(region, cacheFlag);
232 return borderBoxRect();
234 // We have cached insets.
235 LayoutUnit logicalWidth = boxInfo->logicalWidth();
236 LayoutUnit logicalLeft = boxInfo->logicalLeft();
238 // Now apply the parent inset since it is cumulative whenever anything in the containing block chain shifts.
239 // FIXME: Doesn't work right with perpendicular writing modes.
240 const RenderBlock* currentBox = containingBlock();
241 RenderBoxRegionInfo* currentBoxInfo = isRenderFlowThread() ? nullptr : currentBox->renderBoxRegionInfo(region);
242 while (currentBoxInfo && currentBoxInfo->isShifted()) {
243 if (currentBox->style().direction() == LTR)
244 logicalLeft += currentBoxInfo->logicalLeft();
246 logicalLeft -= (currentBox->logicalWidth() - currentBoxInfo->logicalWidth()) - currentBoxInfo->logicalLeft();
248 // Once we reach the fragmentation container we should stop.
249 if (currentBox->isRenderFlowThread())
252 currentBox = currentBox->containingBlock();
255 region = currentBox->clampToStartAndEndRegions(region);
256 currentBoxInfo = currentBox->renderBoxRegionInfo(region);
259 if (cacheFlag == DoNotCacheRenderBoxRegionInfo)
262 if (isHorizontalWritingMode())
263 return LayoutRect(logicalLeft, 0, logicalWidth, height());
264 return LayoutRect(0, logicalLeft, width(), logicalWidth);
267 static RenderBlockFlow* outermostBlockContainingFloatingObject(RenderBox& box)
269 ASSERT(box.isFloating());
270 RenderBlockFlow* parentBlock = nullptr;
271 for (auto& ancestor : ancestorsOfType<RenderBlockFlow>(box)) {
272 if (ancestor.isRenderView())
274 if (!parentBlock || ancestor.containsFloat(box))
275 parentBlock = &ancestor;
280 void RenderBox::removeFloatingOrPositionedChildFromBlockLists()
282 ASSERT(isFloatingOrOutOfFlowPositioned());
284 if (documentBeingDestroyed())
288 if (RenderBlockFlow* parentBlock = outermostBlockContainingFloatingObject(*this)) {
289 parentBlock->markSiblingsWithFloatsForLayout(this);
290 parentBlock->markAllDescendantsWithFloatsForLayout(this, false);
294 if (isOutOfFlowPositioned())
295 RenderBlock::removePositionedObject(*this);
298 void RenderBox::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
300 s_hadOverflowClip = hasOverflowClip();
302 const RenderStyle* oldStyle = hasInitializedStyle() ? &style() : nullptr;
304 // The background of the root element or the body element could propagate up to
305 // the canvas. Issue full repaint, when our style changes substantially.
306 if (diff >= StyleDifferenceRepaint && (isDocumentElementRenderer() || isBody())) {
307 view().repaintRootContents();
308 if (oldStyle->hasEntirelyFixedBackground() != newStyle.hasEntirelyFixedBackground())
309 view().compositor().rootFixedBackgroundsChanged();
312 // When a layout hint happens and an object's position style changes, we have to do a layout
313 // to dirty the render tree using the old position value now.
314 if (diff == StyleDifferenceLayout && parent() && oldStyle->position() != newStyle.position()) {
315 markContainingBlocksForLayout();
316 if (oldStyle->position() == StaticPosition)
318 else if (newStyle.hasOutOfFlowPosition())
319 parent()->setChildNeedsLayout();
320 if (isFloating() && !isOutOfFlowPositioned() && newStyle.hasOutOfFlowPosition())
321 removeFloatingOrPositionedChildFromBlockLists();
324 view().repaintRootContents();
326 #if ENABLE(CSS_SCROLL_SNAP)
327 if (!newStyle.scrollSnapCoordinates().isEmpty() || (oldStyle && !oldStyle->scrollSnapCoordinates().isEmpty())) {
328 if (newStyle.scrollSnapCoordinates().isEmpty())
329 view().unregisterBoxWithScrollSnapCoordinates(*this);
331 view().registerBoxWithScrollSnapCoordinates(*this);
335 RenderBoxModelObject::styleWillChange(diff, newStyle);
338 void RenderBox::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
340 // Horizontal writing mode definition is updated in RenderBoxModelObject::updateFromStyle,
341 // (as part of the RenderBoxModelObject::styleDidChange call below). So, we can safely cache the horizontal
342 // writing mode value before style change here.
343 bool oldHorizontalWritingMode = isHorizontalWritingMode();
345 RenderBoxModelObject::styleDidChange(diff, oldStyle);
347 const RenderStyle& newStyle = style();
348 if (needsLayout() && oldStyle) {
349 RenderBlock::removePercentHeightDescendantIfNeeded(*this);
351 // Normally we can do optimized positioning layout for absolute/fixed positioned objects. There is one special case, however, which is
352 // when the positioned object's margin-before is changed. In this case the parent has to get a layout in order to run margin collapsing
353 // to determine the new static position.
354 if (isOutOfFlowPositioned() && newStyle.hasStaticBlockPosition(isHorizontalWritingMode()) && oldStyle->marginBefore() != newStyle.marginBefore()
355 && parent() && !parent()->normalChildNeedsLayout())
356 parent()->setChildNeedsLayout();
359 if (RenderBlock::hasPercentHeightContainerMap() && firstChild()
360 && oldHorizontalWritingMode != isHorizontalWritingMode())
361 RenderBlock::clearPercentHeightDescendantsFrom(*this);
363 // If our zoom factor changes and we have a defined scrollLeft/Top, we need to adjust that value into the
364 // new zoomed coordinate space.
365 if (hasOverflowClip() && layer() && oldStyle && oldStyle->effectiveZoom() != newStyle.effectiveZoom()) {
366 if (int left = layer()->scrollOffset().x()) {
367 left = (left / oldStyle->effectiveZoom()) * newStyle.effectiveZoom();
368 layer()->scrollToXOffset(left);
370 if (int top = layer()->scrollOffset().y()) {
371 top = (top / oldStyle->effectiveZoom()) * newStyle.effectiveZoom();
372 layer()->scrollToYOffset(top);
376 // Our opaqueness might have changed without triggering layout.
377 if (diff >= StyleDifferenceRepaint && diff <= StyleDifferenceRepaintLayer) {
378 auto parentToInvalidate = parent();
379 for (unsigned i = 0; i < backgroundObscurationTestMaxDepth && parentToInvalidate; ++i) {
380 parentToInvalidate->invalidateBackgroundObscurationStatus();
381 parentToInvalidate = parentToInvalidate->parent();
385 bool isBodyRenderer = isBody();
386 bool isDocElementRenderer = isDocumentElementRenderer();
388 if (isDocElementRenderer || isBodyRenderer) {
389 // Propagate the new writing mode and direction up to the RenderView.
390 auto* documentElementRenderer = document().documentElement()->renderer();
391 auto& viewStyle = view().mutableStyle();
392 bool viewChangedWritingMode = false;
393 bool rootStyleChanged = false;
394 bool viewStyleChanged = false;
395 auto* rootRenderer = isBodyRenderer ? documentElementRenderer : nullptr;
396 if (viewStyle.direction() != newStyle.direction() && (isDocElementRenderer || !documentElementRenderer->style().hasExplicitlySetDirection())) {
397 viewStyle.setDirection(newStyle.direction());
398 viewStyleChanged = true;
399 if (isBodyRenderer) {
400 rootRenderer->mutableStyle().setDirection(newStyle.direction());
401 rootStyleChanged = true;
403 setNeedsLayoutAndPrefWidthsRecalc();
406 if (viewStyle.writingMode() != newStyle.writingMode() && (isDocElementRenderer || !documentElementRenderer->style().hasExplicitlySetWritingMode())) {
407 viewStyle.setWritingMode(newStyle.writingMode());
408 viewChangedWritingMode = true;
409 viewStyleChanged = true;
410 view().setHorizontalWritingMode(newStyle.isHorizontalWritingMode());
411 view().markAllDescendantsWithFloatsForLayout();
412 if (isBodyRenderer) {
413 rootStyleChanged = true;
414 rootRenderer->mutableStyle().setWritingMode(newStyle.writingMode());
415 rootRenderer->setHorizontalWritingMode(newStyle.isHorizontalWritingMode());
417 setNeedsLayoutAndPrefWidthsRecalc();
420 view().frameView().recalculateScrollbarOverlayStyle();
422 const Pagination& pagination = view().frameView().pagination();
423 if (viewChangedWritingMode && pagination.mode != Pagination::Unpaginated) {
424 viewStyle.setColumnStylesFromPaginationMode(pagination.mode);
425 if (view().multiColumnFlowThread())
426 view().updateColumnProgressionFromStyle(viewStyle);
429 if (viewStyleChanged && view().multiColumnFlowThread())
430 view().updateStylesForColumnChildren();
432 if (rootStyleChanged && is<RenderBlockFlow>(rootRenderer) && downcast<RenderBlockFlow>(*rootRenderer).multiColumnFlowThread())
433 downcast<RenderBlockFlow>(*rootRenderer).updateStylesForColumnChildren();
435 if (isBodyRenderer && pagination.mode != Pagination::Unpaginated && frame().page()->paginationLineGridEnabled()) {
436 // Propagate the body font back up to the RenderView and use it as
437 // the basis of the grid.
438 if (newStyle.fontDescription() != view().style().fontDescription()) {
439 view().mutableStyle().setFontDescription(newStyle.fontDescription());
440 view().mutableStyle().fontCascade().update(&document().fontSelector());
444 if (diff != StyleDifferenceEqual)
445 view().compositor().rootOrBodyStyleChanged(*this, oldStyle);
448 #if ENABLE(CSS_SHAPES)
449 if ((oldStyle && oldStyle->shapeOutside()) || style().shapeOutside())
450 updateShapeOutsideInfoAfterStyleChange(style(), oldStyle);
454 void RenderBox::willBeRemovedFromTree()
456 #if ENABLE(CSS_SCROLL_SNAP)
457 if (hasInitializedStyle() && !style().scrollSnapCoordinates().isEmpty())
458 view().unregisterBoxWithScrollSnapCoordinates(*this);
461 RenderBoxModelObject::willBeRemovedFromTree();
465 #if ENABLE(CSS_SHAPES)
466 void RenderBox::updateShapeOutsideInfoAfterStyleChange(const RenderStyle& style, const RenderStyle* oldStyle)
468 const ShapeValue* shapeOutside = style.shapeOutside();
469 const ShapeValue* oldShapeOutside = oldStyle ? oldStyle->shapeOutside() : nullptr;
471 Length shapeMargin = style.shapeMargin();
472 Length oldShapeMargin = oldStyle ? oldStyle->shapeMargin() : RenderStyle::initialShapeMargin();
474 float shapeImageThreshold = style.shapeImageThreshold();
475 float oldShapeImageThreshold = oldStyle ? oldStyle->shapeImageThreshold() : RenderStyle::initialShapeImageThreshold();
477 // FIXME: A future optimization would do a deep comparison for equality. (bug 100811)
478 if (shapeOutside == oldShapeOutside && shapeMargin == oldShapeMargin && shapeImageThreshold == oldShapeImageThreshold)
482 ShapeOutsideInfo::removeInfo(*this);
484 ShapeOutsideInfo::ensureInfo(*this).markShapeAsDirty();
486 if (shapeOutside || shapeOutside != oldShapeOutside)
487 markShapeOutsideDependentsForLayout();
491 void RenderBox::updateFromStyle()
493 RenderBoxModelObject::updateFromStyle();
495 const RenderStyle& styleToUse = style();
496 bool isDocElementRenderer = isDocumentElementRenderer();
497 bool isViewObject = isRenderView();
499 // The root and the RenderView always paint their backgrounds/borders.
500 if (isDocElementRenderer || isViewObject)
501 setHasVisibleBoxDecorations(true);
503 setFloating(!isOutOfFlowPositioned() && styleToUse.isFloating());
505 // We also handle <body> and <html>, whose overflow applies to the viewport.
506 if (styleToUse.overflowX() != OVISIBLE && !isDocElementRenderer && isRenderBlock()) {
507 bool boxHasOverflowClip = true;
509 // Overflow on the body can propagate to the viewport under the following conditions.
510 // (1) The root element is <html>.
511 // (2) We are the primary <body> (can be checked by looking at document.body).
512 // (3) The root element has visible overflow.
513 if (is<HTMLHtmlElement>(*document().documentElement())
514 && document().body() == element()
515 && document().documentElement()->renderer()->style().overflowX() == OVISIBLE) {
516 boxHasOverflowClip = false;
519 // Check for overflow clip.
520 // It's sufficient to just check one direction, since it's illegal to have visible on only one overflow value.
521 if (boxHasOverflowClip) {
522 if (!s_hadOverflowClip && hasRenderOverflow()) {
523 // Erase the overflow.
524 // Overflow changes have to result in immediate repaints of the entire layout overflow area because
525 // repaints issued by removal of descendants get clipped using the updated style when they shouldn't.
526 repaintRectangle(visualOverflowRect());
527 repaintRectangle(layoutOverflowRect());
529 setHasOverflowClip();
532 setHasTransformRelatedProperty(styleToUse.hasTransformRelatedProperty());
533 setHasReflection(styleToUse.boxReflect());
536 void RenderBox::layout()
538 StackStats::LayoutCheckPoint layoutCheckPoint;
539 ASSERT(needsLayout());
541 RenderObject* child = firstChild();
547 LayoutStateMaintainer statePusher(view(), *this, locationOffset(), style().isFlippedBlocksWritingMode());
549 if (child->needsLayout())
550 downcast<RenderElement>(*child).layout();
551 ASSERT(!child->needsLayout());
552 child = child->nextSibling();
555 invalidateBackgroundObscurationStatus();
559 // More IE extensions. clientWidth and clientHeight represent the interior of an object
560 // excluding border and scrollbar.
561 LayoutUnit RenderBox::clientWidth() const
563 return width() - borderLeft() - borderRight() - verticalScrollbarWidth();
566 LayoutUnit RenderBox::clientHeight() const
568 return height() - borderTop() - borderBottom() - horizontalScrollbarHeight();
571 int RenderBox::scrollWidth() const
573 if (hasOverflowClip() && layer())
574 return layer()->scrollWidth();
575 // For objects with visible overflow, this matches IE.
576 // FIXME: Need to work right with writing modes.
577 if (style().isLeftToRightDirection()) {
578 // FIXME: This should use snappedIntSize() instead with absolute coordinates.
579 return roundToInt(std::max(clientWidth(), layoutOverflowRect().maxX() - borderLeft()));
581 return roundToInt(clientWidth() - std::min<LayoutUnit>(0, layoutOverflowRect().x() - borderLeft()));
584 int RenderBox::scrollHeight() const
586 if (hasOverflowClip() && layer())
587 return layer()->scrollHeight();
588 // For objects with visible overflow, this matches IE.
589 // FIXME: Need to work right with writing modes.
590 // FIXME: This should use snappedIntSize() instead with absolute coordinates.
591 return roundToInt(std::max(clientHeight(), layoutOverflowRect().maxY() - borderTop()));
594 int RenderBox::scrollLeft() const
596 return hasOverflowClip() && layer() ? layer()->scrollPosition().x() : 0;
599 int RenderBox::scrollTop() const
601 return hasOverflowClip() && layer() ? layer()->scrollPosition().y() : 0;
604 static void setupWheelEventTestTrigger(RenderLayer& layer, Frame* frame)
609 Page* page = frame->page();
610 if (!page || !page->expectsWheelEventTriggers())
613 layer.scrollAnimator().setWheelEventTestTrigger(page->testTrigger());
616 void RenderBox::setScrollLeft(int newLeft)
618 if (!hasOverflowClip() || !layer())
620 setupWheelEventTestTrigger(*layer(), document().frame());
621 layer()->scrollToXPosition(newLeft, RenderLayer::ScrollOffsetClamped);
624 void RenderBox::setScrollTop(int newTop)
626 if (!hasOverflowClip() || !layer())
628 setupWheelEventTestTrigger(*layer(), document().frame());
629 layer()->scrollToYPosition(newTop, RenderLayer::ScrollOffsetClamped);
632 void RenderBox::absoluteRects(Vector<IntRect>& rects, const LayoutPoint& accumulatedOffset) const
634 rects.append(snappedIntRect(accumulatedOffset, size()));
637 void RenderBox::absoluteQuads(Vector<FloatQuad>& quads, bool* wasFixed) const
639 FloatRect localRect(0, 0, width(), height());
641 RenderFlowThread* flowThread = flowThreadContainingBlock();
642 if (flowThread && flowThread->absoluteQuadsForBox(quads, wasFixed, this, localRect.y(), localRect.maxY()))
645 quads.append(localToAbsoluteQuad(localRect, UseTransforms, wasFixed));
648 void RenderBox::updateLayerTransform()
650 // Transform-origin depends on box size, so we need to update the layer transform after layout.
652 layer()->updateTransform();
655 LayoutUnit RenderBox::constrainLogicalWidthInRegionByMinMax(LayoutUnit logicalWidth, LayoutUnit availableWidth, RenderBlock& cb, RenderRegion* region) const
657 const RenderStyle& styleToUse = style();
658 if (!styleToUse.logicalMaxWidth().isUndefined())
659 logicalWidth = std::min(logicalWidth, computeLogicalWidthInRegionUsing(MaxSize, styleToUse.logicalMaxWidth(), availableWidth, cb, region));
660 return std::max(logicalWidth, computeLogicalWidthInRegionUsing(MinSize, styleToUse.logicalMinWidth(), availableWidth, cb, region));
663 LayoutUnit RenderBox::constrainLogicalHeightByMinMax(LayoutUnit logicalHeight, Optional<LayoutUnit> intrinsicContentHeight) const
665 const RenderStyle& styleToUse = style();
666 if (!styleToUse.logicalMaxHeight().isUndefined()) {
667 if (Optional<LayoutUnit> maxH = computeLogicalHeightUsing(MaxSize, styleToUse.logicalMaxHeight(), intrinsicContentHeight))
668 logicalHeight = std::min(logicalHeight, maxH.value());
670 if (Optional<LayoutUnit> computedLogicalHeight = computeLogicalHeightUsing(MinSize, styleToUse.logicalMinHeight(), intrinsicContentHeight))
671 return std::max(logicalHeight, computedLogicalHeight.value());
672 return logicalHeight;
675 LayoutUnit RenderBox::constrainContentBoxLogicalHeightByMinMax(LayoutUnit logicalHeight, Optional<LayoutUnit> intrinsicContentHeight) const
677 const RenderStyle& styleToUse = style();
678 if (!styleToUse.logicalMaxHeight().isUndefined()) {
679 if (Optional<LayoutUnit> maxH = computeContentLogicalHeight(MaxSize, styleToUse.logicalMaxHeight(), intrinsicContentHeight))
680 logicalHeight = std::min(logicalHeight, maxH.value());
682 if (Optional<LayoutUnit> computedContentLogicalHeight = computeContentLogicalHeight(MinSize, styleToUse.logicalMinHeight(), intrinsicContentHeight))
683 return std::max(logicalHeight, computedContentLogicalHeight.value());
684 return logicalHeight;
687 RoundedRect::Radii RenderBox::borderRadii() const
689 auto& style = this->style();
690 LayoutRect bounds = frameRect();
692 unsigned borderLeft = style.borderLeftWidth();
693 unsigned borderTop = style.borderTopWidth();
694 bounds.moveBy(LayoutPoint(borderLeft, borderTop));
695 bounds.contract(borderLeft + style.borderRightWidth(), borderTop + style.borderBottomWidth());
696 return style.getRoundedBorderFor(bounds).radii();
699 LayoutRect RenderBox::contentBoxRect() const
701 LayoutUnit x = borderLeft() + paddingLeft();
702 if (shouldPlaceBlockDirectionScrollbarOnLeft())
703 x += verticalScrollbarWidth();
704 LayoutUnit y = borderTop() + paddingTop();
705 return LayoutRect(x, y, contentWidth(), contentHeight());
708 IntRect RenderBox::absoluteContentBox() const
710 // This is wrong with transforms and flipped writing modes.
711 IntRect rect = snappedIntRect(contentBoxRect());
712 FloatPoint absPos = localToAbsolute();
713 rect.move(absPos.x(), absPos.y());
717 FloatQuad RenderBox::absoluteContentQuad() const
719 LayoutRect rect = contentBoxRect();
720 return localToAbsoluteQuad(FloatRect(rect));
723 LayoutRect RenderBox::outlineBoundsForRepaint(const RenderLayerModelObject* repaintContainer, const RenderGeometryMap* geometryMap) const
725 LayoutRect box = borderBoundingBox();
726 adjustRectForOutlineAndShadow(box);
728 if (repaintContainer != this) {
729 FloatQuad containerRelativeQuad;
731 containerRelativeQuad = geometryMap->mapToContainer(box, repaintContainer);
733 containerRelativeQuad = localToContainerQuad(FloatRect(box), repaintContainer);
735 box = LayoutRect(containerRelativeQuad.boundingBox());
738 // FIXME: layoutDelta needs to be applied in parts before/after transforms and
739 // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
740 box.move(view().layoutDelta());
742 return LayoutRect(snapRectToDevicePixels(box, document().deviceScaleFactor()));
745 void RenderBox::addFocusRingRects(Vector<LayoutRect>& rects, const LayoutPoint& additionalOffset, const RenderLayerModelObject*)
747 if (!size().isEmpty())
748 rects.append(LayoutRect(additionalOffset, size()));
751 int RenderBox::reflectionOffset() const
753 if (!style().boxReflect())
755 if (style().boxReflect()->direction() == ReflectionLeft || style().boxReflect()->direction() == ReflectionRight)
756 return valueForLength(style().boxReflect()->offset(), borderBoxRect().width());
757 return valueForLength(style().boxReflect()->offset(), borderBoxRect().height());
760 LayoutRect RenderBox::reflectedRect(const LayoutRect& r) const
762 if (!style().boxReflect())
765 LayoutRect box = borderBoxRect();
766 LayoutRect result = r;
767 switch (style().boxReflect()->direction()) {
768 case ReflectionBelow:
769 result.setY(box.maxY() + reflectionOffset() + (box.maxY() - r.maxY()));
771 case ReflectionAbove:
772 result.setY(box.y() - reflectionOffset() - box.height() + (box.maxY() - r.maxY()));
775 result.setX(box.x() - reflectionOffset() - box.width() + (box.maxX() - r.maxX()));
777 case ReflectionRight:
778 result.setX(box.maxX() + reflectionOffset() + (box.maxX() - r.maxX()));
784 bool RenderBox::fixedElementLaysOutRelativeToFrame(const FrameView& frameView) const
786 return style().position() == FixedPosition && container()->isRenderView() && frameView.fixedElementsLayoutRelativeToFrame();
789 bool RenderBox::includeVerticalScrollbarSize() const
791 return hasOverflowClip() && layer() && !layer()->hasOverlayScrollbars()
792 && (style().overflowY() == OSCROLL || style().overflowY() == OAUTO);
795 bool RenderBox::includeHorizontalScrollbarSize() const
797 return hasOverflowClip() && layer() && !layer()->hasOverlayScrollbars()
798 && (style().overflowX() == OSCROLL || style().overflowX() == OAUTO);
801 int RenderBox::verticalScrollbarWidth() const
803 return includeVerticalScrollbarSize() ? layer()->verticalScrollbarWidth() : 0;
806 int RenderBox::horizontalScrollbarHeight() const
808 return includeHorizontalScrollbarSize() ? layer()->horizontalScrollbarHeight() : 0;
811 int RenderBox::intrinsicScrollbarLogicalWidth() const
813 if (!hasOverflowClip())
816 if (isHorizontalWritingMode() && (style().overflowY() == OSCROLL && !hasVerticalScrollbarWithAutoBehavior())) {
817 ASSERT(layer() && layer()->hasVerticalScrollbar());
818 return verticalScrollbarWidth();
821 if (!isHorizontalWritingMode() && (style().overflowX() == OSCROLL && !hasHorizontalScrollbarWithAutoBehavior())) {
822 ASSERT(layer() && layer()->hasHorizontalScrollbar());
823 return horizontalScrollbarHeight();
829 bool RenderBox::scrollLayer(ScrollDirection direction, ScrollGranularity granularity, float multiplier, Element** stopElement)
831 RenderLayer* boxLayer = layer();
832 if (boxLayer && boxLayer->scroll(direction, granularity, multiplier)) {
834 *stopElement = element();
842 bool RenderBox::scroll(ScrollDirection direction, ScrollGranularity granularity, float multiplier, Element** stopElement, RenderBox* startBox, const IntPoint& wheelEventAbsolutePoint)
844 if (scrollLayer(direction, granularity, multiplier, stopElement))
847 if (stopElement && *stopElement && *stopElement == element())
850 RenderBlock* nextScrollBlock = containingBlock();
851 if (is<RenderNamedFlowThread>(nextScrollBlock)) {
853 nextScrollBlock = downcast<RenderNamedFlowThread>(*nextScrollBlock).fragmentFromAbsolutePointAndBox(wheelEventAbsolutePoint, *startBox);
856 if (nextScrollBlock && !nextScrollBlock->isRenderView())
857 return nextScrollBlock->scroll(direction, granularity, multiplier, stopElement, startBox, wheelEventAbsolutePoint);
862 bool RenderBox::logicalScroll(ScrollLogicalDirection direction, ScrollGranularity granularity, float multiplier, Element** stopElement)
864 bool scrolled = false;
866 RenderLayer* l = layer();
869 // On Mac only we reset the inline direction position when doing a document scroll (e.g., hitting Home/End).
870 if (granularity == ScrollByDocument)
871 scrolled = l->scroll(logicalToPhysical(ScrollInlineDirectionBackward, isHorizontalWritingMode(), style().isFlippedBlocksWritingMode()), ScrollByDocument, multiplier);
873 if (l->scroll(logicalToPhysical(direction, isHorizontalWritingMode(), style().isFlippedBlocksWritingMode()), granularity, multiplier))
878 *stopElement = element();
883 if (stopElement && *stopElement && *stopElement == element())
886 RenderBlock* b = containingBlock();
887 if (b && !b->isRenderView())
888 return b->logicalScroll(direction, granularity, multiplier, stopElement);
892 bool RenderBox::canBeScrolledAndHasScrollableArea() const
894 return canBeProgramaticallyScrolled() && (hasHorizontalOverflow() || hasVerticalOverflow());
897 bool RenderBox::isScrollableOrRubberbandableBox() const
899 return canBeScrolledAndHasScrollableArea();
902 // FIXME: This is badly named. overflow:hidden can be programmatically scrolled, yet this returns false in that case.
903 bool RenderBox::canBeProgramaticallyScrolled() const
908 if (!hasOverflowClip())
911 if (hasScrollableOverflowX() || hasScrollableOverflowY())
914 return element() && element()->hasEditableStyle();
917 bool RenderBox::usesCompositedScrolling() const
919 return hasOverflowClip() && hasLayer() && layer()->usesCompositedScrolling();
922 void RenderBox::autoscroll(const IntPoint& position)
925 layer()->autoscroll(position);
928 // There are two kinds of renderer that can autoscroll.
929 bool RenderBox::canAutoscroll() const
932 return view().frameView().isScrollable();
934 // Check for a box that can be scrolled in its own right.
935 if (canBeScrolledAndHasScrollableArea())
941 // If specified point is in border belt, returned offset denotes direction of
943 IntSize RenderBox::calculateAutoscrollDirection(const IntPoint& windowPoint) const
945 IntRect box(absoluteBoundingBoxRect());
946 box.moveBy(view().frameView().scrollPosition());
947 IntRect windowBox = view().frameView().contentsToWindow(box);
949 IntPoint windowAutoscrollPoint = windowPoint;
951 if (windowAutoscrollPoint.x() < windowBox.x() + autoscrollBeltSize)
952 windowAutoscrollPoint.move(-autoscrollBeltSize, 0);
953 else if (windowAutoscrollPoint.x() > windowBox.maxX() - autoscrollBeltSize)
954 windowAutoscrollPoint.move(autoscrollBeltSize, 0);
956 if (windowAutoscrollPoint.y() < windowBox.y() + autoscrollBeltSize)
957 windowAutoscrollPoint.move(0, -autoscrollBeltSize);
958 else if (windowAutoscrollPoint.y() > windowBox.maxY() - autoscrollBeltSize)
959 windowAutoscrollPoint.move(0, autoscrollBeltSize);
961 return windowAutoscrollPoint - windowPoint;
964 RenderBox* RenderBox::findAutoscrollable(RenderObject* renderer)
966 while (renderer && !(is<RenderBox>(*renderer) && downcast<RenderBox>(*renderer).canAutoscroll())) {
967 if (is<RenderView>(*renderer) && renderer->document().ownerElement())
968 renderer = renderer->document().ownerElement()->renderer();
970 renderer = renderer->parent();
973 return is<RenderBox>(renderer) ? downcast<RenderBox>(renderer) : nullptr;
976 void RenderBox::panScroll(const IntPoint& source)
979 layer()->panScrollFromPoint(source);
982 bool RenderBox::hasVerticalScrollbarWithAutoBehavior() const
984 bool overflowScrollActsLikeAuto = style().overflowY() == OSCROLL && !style().hasPseudoStyle(SCROLLBAR) && ScrollbarTheme::theme().usesOverlayScrollbars();
985 return hasOverflowClip() && (style().overflowY() == OAUTO || style().overflowY() == OOVERLAY || overflowScrollActsLikeAuto);
988 bool RenderBox::hasHorizontalScrollbarWithAutoBehavior() const
990 bool overflowScrollActsLikeAuto = style().overflowX() == OSCROLL && !style().hasPseudoStyle(SCROLLBAR) && ScrollbarTheme::theme().usesOverlayScrollbars();
991 return hasOverflowClip() && (style().overflowX() == OAUTO || style().overflowX() == OOVERLAY || overflowScrollActsLikeAuto);
994 bool RenderBox::needsPreferredWidthsRecalculation() const
996 return style().paddingStart().isPercentOrCalculated() || style().paddingEnd().isPercentOrCalculated();
999 ScrollPosition RenderBox::scrollPosition() const
1001 if (!hasOverflowClip())
1005 return layer()->scrollPosition();
1008 LayoutSize RenderBox::cachedSizeForOverflowClip() const
1010 ASSERT(hasOverflowClip());
1012 return layer()->size();
1015 void RenderBox::applyCachedClipAndScrollOffsetForRepaint(LayoutRect& paintRect) const
1017 flipForWritingMode(paintRect);
1018 paintRect.moveBy(-scrollPosition()); // For overflow:auto/scroll/hidden.
1020 // Do not clip scroll layer contents to reduce the number of repaints while scrolling.
1021 if (usesCompositedScrolling()) {
1022 flipForWritingMode(paintRect);
1026 // height() is inaccurate if we're in the middle of a layout of this RenderBox, so use the
1027 // layer's size instead. Even if the layer's size is wrong, the layer itself will repaint
1028 // anyway if its size does change.
1029 LayoutRect clipRect(LayoutPoint(), cachedSizeForOverflowClip());
1030 paintRect = intersection(paintRect, clipRect);
1031 flipForWritingMode(paintRect);
1034 void RenderBox::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
1036 minLogicalWidth = minPreferredLogicalWidth() - borderAndPaddingLogicalWidth();
1037 maxLogicalWidth = maxPreferredLogicalWidth() - borderAndPaddingLogicalWidth();
1040 LayoutUnit RenderBox::minPreferredLogicalWidth() const
1042 if (preferredLogicalWidthsDirty()) {
1044 SetLayoutNeededForbiddenScope layoutForbiddenScope(const_cast<RenderBox*>(this));
1046 const_cast<RenderBox*>(this)->computePreferredLogicalWidths();
1049 return m_minPreferredLogicalWidth;
1052 LayoutUnit RenderBox::maxPreferredLogicalWidth() const
1054 if (preferredLogicalWidthsDirty()) {
1056 SetLayoutNeededForbiddenScope layoutForbiddenScope(const_cast<RenderBox*>(this));
1058 const_cast<RenderBox*>(this)->computePreferredLogicalWidths();
1061 return m_maxPreferredLogicalWidth;
1064 bool RenderBox::hasOverrideLogicalContentHeight() const
1066 return gOverrideHeightMap && gOverrideHeightMap->contains(this);
1069 bool RenderBox::hasOverrideLogicalContentWidth() const
1071 return gOverrideWidthMap && gOverrideWidthMap->contains(this);
1074 void RenderBox::setOverrideLogicalContentHeight(LayoutUnit height)
1076 if (!gOverrideHeightMap)
1077 gOverrideHeightMap = new OverrideSizeMap();
1078 gOverrideHeightMap->set(this, height);
1081 void RenderBox::setOverrideLogicalContentWidth(LayoutUnit width)
1083 if (!gOverrideWidthMap)
1084 gOverrideWidthMap = new OverrideSizeMap();
1085 gOverrideWidthMap->set(this, width);
1088 void RenderBox::clearOverrideLogicalContentHeight()
1090 if (gOverrideHeightMap)
1091 gOverrideHeightMap->remove(this);
1094 void RenderBox::clearOverrideLogicalContentWidth()
1096 if (gOverrideWidthMap)
1097 gOverrideWidthMap->remove(this);
1100 void RenderBox::clearOverrideSize()
1102 clearOverrideLogicalContentHeight();
1103 clearOverrideLogicalContentWidth();
1106 LayoutUnit RenderBox::overrideLogicalContentWidth() const
1108 ASSERT(hasOverrideLogicalContentWidth());
1109 return gOverrideWidthMap->get(this);
1112 LayoutUnit RenderBox::overrideLogicalContentHeight() const
1114 ASSERT(hasOverrideLogicalContentHeight());
1115 return gOverrideHeightMap->get(this);
1118 #if ENABLE(CSS_GRID_LAYOUT)
1119 Optional<LayoutUnit> RenderBox::overrideContainingBlockContentLogicalWidth() const
1121 ASSERT(hasOverrideContainingBlockLogicalWidth());
1122 return gOverrideContainingBlockLogicalWidthMap->get(this);
1125 Optional<LayoutUnit> RenderBox::overrideContainingBlockContentLogicalHeight() const
1127 ASSERT(hasOverrideContainingBlockLogicalHeight());
1128 return gOverrideContainingBlockLogicalHeightMap->get(this);
1131 bool RenderBox::hasOverrideContainingBlockLogicalWidth() const
1133 return gOverrideContainingBlockLogicalWidthMap && gOverrideContainingBlockLogicalWidthMap->contains(this);
1136 bool RenderBox::hasOverrideContainingBlockLogicalHeight() const
1138 return gOverrideContainingBlockLogicalHeightMap && gOverrideContainingBlockLogicalHeightMap->contains(this);
1141 void RenderBox::setOverrideContainingBlockContentLogicalWidth(Optional<LayoutUnit> logicalWidth)
1143 if (!gOverrideContainingBlockLogicalWidthMap)
1144 gOverrideContainingBlockLogicalWidthMap = new OverrideOptionalSizeMap;
1145 gOverrideContainingBlockLogicalWidthMap->set(this, logicalWidth);
1148 void RenderBox::setOverrideContainingBlockContentLogicalHeight(Optional<LayoutUnit> logicalHeight)
1150 if (!gOverrideContainingBlockLogicalHeightMap)
1151 gOverrideContainingBlockLogicalHeightMap = new OverrideOptionalSizeMap;
1152 gOverrideContainingBlockLogicalHeightMap->set(this, logicalHeight);
1155 void RenderBox::clearContainingBlockOverrideSize()
1157 if (gOverrideContainingBlockLogicalWidthMap)
1158 gOverrideContainingBlockLogicalWidthMap->remove(this);
1159 clearOverrideContainingBlockContentLogicalHeight();
1162 void RenderBox::clearOverrideContainingBlockContentLogicalHeight()
1164 if (gOverrideContainingBlockLogicalHeightMap)
1165 gOverrideContainingBlockLogicalHeightMap->remove(this);
1168 LayoutUnit RenderBox::extraInlineOffset() const
1170 return gExtraInlineOffsetMap ? gExtraInlineOffsetMap->get(this) : LayoutUnit();
1173 LayoutUnit RenderBox::extraBlockOffset() const
1175 return gExtraBlockOffsetMap ? gExtraBlockOffsetMap->get(this) : LayoutUnit();
1178 void RenderBox::setExtraInlineOffset(LayoutUnit inlineOffest)
1180 if (!gExtraInlineOffsetMap)
1181 gExtraInlineOffsetMap = new OverrideSizeMap;
1182 gExtraInlineOffsetMap->set(this, inlineOffest);
1185 void RenderBox::setExtraBlockOffset(LayoutUnit blockOffest)
1187 if (!gExtraBlockOffsetMap)
1188 gExtraBlockOffsetMap = new OverrideSizeMap;
1189 gExtraBlockOffsetMap->set(this, blockOffest);
1192 void RenderBox::clearExtraInlineAndBlockOffests()
1194 if (gExtraInlineOffsetMap)
1195 gExtraInlineOffsetMap->remove(this);
1196 if (gExtraBlockOffsetMap)
1197 gExtraBlockOffsetMap->remove(this);
1199 #endif // ENABLE(CSS_GRID_LAYOUT)
1201 LayoutUnit RenderBox::adjustBorderBoxLogicalWidthForBoxSizing(LayoutUnit width) const
1203 LayoutUnit bordersPlusPadding = borderAndPaddingLogicalWidth();
1204 if (style().boxSizing() == CONTENT_BOX)
1205 return width + bordersPlusPadding;
1206 return std::max(width, bordersPlusPadding);
1209 LayoutUnit RenderBox::adjustBorderBoxLogicalHeightForBoxSizing(LayoutUnit height) const
1211 LayoutUnit bordersPlusPadding = borderAndPaddingLogicalHeight();
1212 if (style().boxSizing() == CONTENT_BOX)
1213 return height + bordersPlusPadding;
1214 return std::max(height, bordersPlusPadding);
1217 LayoutUnit RenderBox::adjustContentBoxLogicalWidthForBoxSizing(LayoutUnit width) const
1219 if (style().boxSizing() == BORDER_BOX)
1220 width -= borderAndPaddingLogicalWidth();
1221 return std::max<LayoutUnit>(0, width);
1224 LayoutUnit RenderBox::adjustContentBoxLogicalHeightForBoxSizing(Optional<LayoutUnit> height) const
1228 LayoutUnit result = height.value();
1229 if (style().boxSizing() == BORDER_BOX)
1230 result -= borderAndPaddingLogicalHeight();
1231 return std::max(LayoutUnit(), result);
1235 bool RenderBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction action)
1237 LayoutPoint adjustedLocation = accumulatedOffset + location();
1239 // Check kids first.
1240 for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
1241 if (!child->hasLayer() && child->nodeAtPoint(request, result, locationInContainer, adjustedLocation, action)) {
1242 updateHitTestResult(result, locationInContainer.point() - toLayoutSize(adjustedLocation));
1247 RenderFlowThread* flowThread = flowThreadContainingBlock();
1248 RenderRegion* regionToUse = flowThread ? downcast<RenderNamedFlowFragment>(flowThread->currentRegion()) : nullptr;
1250 // If the box is not contained by this region there's no point in going further.
1251 if (regionToUse && !flowThread->objectShouldFragmentInFlowRegion(this, regionToUse))
1254 // Check our bounds next. For this purpose always assume that we can only be hit in the
1255 // foreground phase (which is true for replaced elements like images).
1256 LayoutRect boundsRect = borderBoxRectInRegion(regionToUse);
1257 boundsRect.moveBy(adjustedLocation);
1258 if (visibleToHitTesting() && action == HitTestForeground && locationInContainer.intersects(boundsRect)) {
1259 updateHitTestResult(result, locationInContainer.point() - toLayoutSize(adjustedLocation));
1260 if (!result.addNodeToRectBasedTestResult(element(), request, locationInContainer, boundsRect))
1267 // --------------------- painting stuff -------------------------------
1269 void RenderBox::paintRootBoxFillLayers(const PaintInfo& paintInfo)
1271 if (paintInfo.skipRootBackground())
1274 auto& rootBackgroundRenderer = rendererForRootBackground();
1276 const FillLayer* bgLayer = rootBackgroundRenderer.style().backgroundLayers();
1277 Color bgColor = rootBackgroundRenderer.style().visitedDependentColor(CSSPropertyBackgroundColor);
1279 paintFillLayers(paintInfo, bgColor, bgLayer, view().backgroundRect(), BackgroundBleedNone, CompositeSourceOver, &rootBackgroundRenderer);
1282 BackgroundBleedAvoidance RenderBox::determineBackgroundBleedAvoidance(GraphicsContext& context) const
1284 if (context.paintingDisabled())
1285 return BackgroundBleedNone;
1287 const RenderStyle& style = this->style();
1289 if (!style.hasBackground() || !style.hasBorder() || !style.hasBorderRadius() || borderImageIsLoadedAndCanBeRendered())
1290 return BackgroundBleedNone;
1292 AffineTransform ctm = context.getCTM();
1293 FloatSize contextScaling(static_cast<float>(ctm.xScale()), static_cast<float>(ctm.yScale()));
1295 // Because RoundedRect uses IntRect internally the inset applied by the
1296 // BackgroundBleedShrinkBackground strategy cannot be less than one integer
1297 // layout coordinate, even with subpixel layout enabled. To take that into
1298 // account, we clamp the contextScaling to 1.0 for the following test so
1299 // that borderObscuresBackgroundEdge can only return true if the border
1300 // widths are greater than 2 in both layout coordinates and screen
1302 // This precaution will become obsolete if RoundedRect is ever promoted to
1303 // a sub-pixel representation.
1304 if (contextScaling.width() > 1)
1305 contextScaling.setWidth(1);
1306 if (contextScaling.height() > 1)
1307 contextScaling.setHeight(1);
1309 if (borderObscuresBackgroundEdge(contextScaling))
1310 return BackgroundBleedShrinkBackground;
1311 if (!style.hasAppearance() && borderObscuresBackground() && backgroundHasOpaqueTopLayer())
1312 return BackgroundBleedBackgroundOverBorder;
1314 return BackgroundBleedUseTransparencyLayer;
1317 void RenderBox::paintBoxDecorations(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
1319 if (!paintInfo.shouldPaintWithinRoot(*this))
1322 LayoutRect paintRect = borderBoxRectInRegion(currentRenderNamedFlowFragment());
1323 paintRect.moveBy(paintOffset);
1326 // Workaround for <rdar://problem/6209763>. Force the painting bounds of checkboxes and radio controls to be square.
1327 if (style().appearance() == CheckboxPart || style().appearance() == RadioPart) {
1328 int width = std::min(paintRect.width(), paintRect.height());
1330 paintRect = IntRect(paintRect.x(), paintRect.y() + (this->height() - height) / 2, width, height); // Vertically center the checkbox, like on desktop
1333 BackgroundBleedAvoidance bleedAvoidance = determineBackgroundBleedAvoidance(paintInfo.context());
1335 // FIXME: Should eventually give the theme control over whether the box shadow should paint, since controls could have
1336 // custom shadows of their own.
1337 if (!boxShadowShouldBeAppliedToBackground(paintRect.location(), bleedAvoidance))
1338 paintBoxShadow(paintInfo, paintRect, style(), Normal);
1340 GraphicsContextStateSaver stateSaver(paintInfo.context(), false);
1341 if (bleedAvoidance == BackgroundBleedUseTransparencyLayer) {
1342 // To avoid the background color bleeding out behind the border, we'll render background and border
1343 // into a transparency layer, and then clip that in one go (which requires setting up the clip before
1344 // beginning the layer).
1346 paintInfo.context().clipRoundedRect(style().getRoundedBorderFor(paintRect).pixelSnappedRoundedRectForPainting(document().deviceScaleFactor()));
1347 paintInfo.context().beginTransparencyLayer(1);
1350 // If we have a native theme appearance, paint that before painting our background.
1351 // The theme will tell us whether or not we should also paint the CSS background.
1352 ControlStates* controlStates = nullptr;
1353 bool borderOrBackgroundPaintingIsNeeded = true;
1354 if (style().hasAppearance()) {
1355 if (hasControlStatesForRenderer(this))
1356 controlStates = controlStatesForRenderer(this);
1358 controlStates = new ControlStates();
1359 addControlStatesForRenderer(this, controlStates);
1361 borderOrBackgroundPaintingIsNeeded = theme().paint(*this, *controlStates, paintInfo, paintRect);
1362 if (controlStates->needsRepaint())
1363 view().scheduleLazyRepaint(*this);
1366 if (borderOrBackgroundPaintingIsNeeded) {
1367 if (bleedAvoidance == BackgroundBleedBackgroundOverBorder)
1368 paintBorder(paintInfo, paintRect, style(), bleedAvoidance);
1370 paintBackground(paintInfo, paintRect, bleedAvoidance);
1372 if (style().hasAppearance())
1373 theme().paintDecorations(*this, paintInfo, paintRect);
1375 paintBoxShadow(paintInfo, paintRect, style(), Inset);
1377 // The theme will tell us whether or not we should also paint the CSS border.
1378 if (bleedAvoidance != BackgroundBleedBackgroundOverBorder && (!style().hasAppearance() || (borderOrBackgroundPaintingIsNeeded && theme().paintBorderOnly(*this, paintInfo, paintRect))) && style().hasVisibleBorderDecoration())
1379 paintBorder(paintInfo, paintRect, style(), bleedAvoidance);
1381 if (bleedAvoidance == BackgroundBleedUseTransparencyLayer)
1382 paintInfo.context().endTransparencyLayer();
1385 void RenderBox::paintBackground(const PaintInfo& paintInfo, const LayoutRect& paintRect, BackgroundBleedAvoidance bleedAvoidance)
1387 if (isDocumentElementRenderer()) {
1388 paintRootBoxFillLayers(paintInfo);
1391 if (isBody() && skipBodyBackground(this))
1393 if (backgroundIsKnownToBeObscured(paintRect.location()) && !boxShadowShouldBeAppliedToBackground(paintRect.location(), bleedAvoidance))
1395 paintFillLayers(paintInfo, style().visitedDependentColor(CSSPropertyBackgroundColor), style().backgroundLayers(), paintRect, bleedAvoidance);
1398 bool RenderBox::getBackgroundPaintedExtent(const LayoutPoint& paintOffset, LayoutRect& paintedExtent) const
1400 ASSERT(hasBackground());
1401 LayoutRect backgroundRect = snappedIntRect(borderBoxRect());
1403 Color backgroundColor = style().visitedDependentColor(CSSPropertyBackgroundColor);
1404 if (backgroundColor.isValid() && backgroundColor.alpha()) {
1405 paintedExtent = backgroundRect;
1409 if (!style().backgroundLayers()->image() || style().backgroundLayers()->next()) {
1410 paintedExtent = backgroundRect;
1414 BackgroundImageGeometry geometry = calculateBackgroundImageGeometry(nullptr, *style().backgroundLayers(), paintOffset, backgroundRect);
1415 paintedExtent = geometry.destRect();
1416 return !geometry.hasNonLocalGeometry();
1419 bool RenderBox::backgroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect) const
1421 if (isBody() && skipBodyBackground(this))
1424 Color backgroundColor = style().visitedDependentColor(CSSPropertyBackgroundColor);
1425 if (!backgroundColor.isValid() || backgroundColor.hasAlpha())
1428 // If the element has appearance, it might be painted by theme.
1429 // We cannot be sure if theme paints the background opaque.
1430 // In this case it is safe to not assume opaqueness.
1431 // FIXME: May be ask theme if it paints opaque.
1432 if (style().hasAppearance())
1434 // FIXME: Check the opaqueness of background images.
1436 if (hasClip() || hasClipPath())
1439 // FIXME: Use rounded rect if border radius is present.
1440 if (style().hasBorderRadius())
1443 // FIXME: The background color clip is defined by the last layer.
1444 if (style().backgroundLayers()->next())
1446 LayoutRect backgroundRect;
1447 switch (style().backgroundClip()) {
1449 backgroundRect = borderBoxRect();
1451 case PaddingFillBox:
1452 backgroundRect = paddingBoxRect();
1454 case ContentFillBox:
1455 backgroundRect = contentBoxRect();
1460 return backgroundRect.contains(localRect);
1463 static bool isCandidateForOpaquenessTest(const RenderBox& childBox)
1465 const RenderStyle& childStyle = childBox.style();
1466 if (childStyle.position() != StaticPosition && childBox.containingBlock() != childBox.parent())
1468 if (childStyle.visibility() != VISIBLE)
1470 #if ENABLE(CSS_SHAPES)
1471 if (childStyle.shapeOutside())
1474 if (!childBox.width() || !childBox.height())
1476 if (RenderLayer* childLayer = childBox.layer()) {
1477 if (childLayer->isComposited())
1479 // FIXME: Deal with z-index.
1480 if (!childStyle.hasAutoZIndex())
1482 if (childLayer->hasTransform() || childLayer->isTransparent() || childLayer->hasFilter())
1484 if (!childBox.scrollPosition().isZero())
1490 bool RenderBox::foregroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect, unsigned maxDepthToTest) const
1492 if (!maxDepthToTest)
1494 for (auto& childBox : childrenOfType<RenderBox>(*this)) {
1495 if (!isCandidateForOpaquenessTest(childBox))
1497 LayoutPoint childLocation = childBox.location();
1498 if (childBox.isRelPositioned())
1499 childLocation.move(childBox.relativePositionOffset());
1500 LayoutRect childLocalRect = localRect;
1501 childLocalRect.moveBy(-childLocation);
1502 if (childLocalRect.y() < 0 || childLocalRect.x() < 0) {
1503 // If there is unobscured area above/left of a static positioned box then the rect is probably not covered.
1504 if (childBox.style().position() == StaticPosition)
1508 if (childLocalRect.maxY() > childBox.height() || childLocalRect.maxX() > childBox.width())
1510 if (childBox.backgroundIsKnownToBeOpaqueInRect(childLocalRect))
1512 if (childBox.foregroundIsKnownToBeOpaqueInRect(childLocalRect, maxDepthToTest - 1))
1518 bool RenderBox::computeBackgroundIsKnownToBeObscured(const LayoutPoint& paintOffset)
1520 // Test to see if the children trivially obscure the background.
1521 // FIXME: This test can be much more comprehensive.
1522 if (!hasBackground())
1524 // Table and root background painting is special.
1525 if (isTable() || isDocumentElementRenderer())
1528 LayoutRect backgroundRect;
1529 if (!getBackgroundPaintedExtent(paintOffset, backgroundRect))
1531 return foregroundIsKnownToBeOpaqueInRect(backgroundRect, backgroundObscurationTestMaxDepth);
1534 bool RenderBox::backgroundHasOpaqueTopLayer() const
1536 const FillLayer* fillLayer = style().backgroundLayers();
1537 if (!fillLayer || fillLayer->clip() != BorderFillBox)
1540 // Clipped with local scrolling
1541 if (hasOverflowClip() && fillLayer->attachment() == LocalBackgroundAttachment)
1544 if (fillLayer->hasOpaqueImage(*this) && fillLayer->hasRepeatXY() && fillLayer->image()->canRender(this, style().effectiveZoom()))
1547 // If there is only one layer and no image, check whether the background color is opaque
1548 if (!fillLayer->next() && !fillLayer->hasImage()) {
1549 Color bgColor = style().visitedDependentColor(CSSPropertyBackgroundColor);
1550 if (bgColor.isValid() && bgColor.alpha() == 255)
1557 void RenderBox::paintMask(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
1559 if (!paintInfo.shouldPaintWithinRoot(*this) || style().visibility() != VISIBLE || paintInfo.phase != PaintPhaseMask || paintInfo.context().paintingDisabled())
1562 LayoutRect paintRect = LayoutRect(paintOffset, size());
1563 paintMaskImages(paintInfo, paintRect);
1566 void RenderBox::paintClippingMask(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
1568 if (!paintInfo.shouldPaintWithinRoot(*this) || style().visibility() != VISIBLE || paintInfo.phase != PaintPhaseClippingMask || paintInfo.context().paintingDisabled())
1571 LayoutRect paintRect = LayoutRect(paintOffset, size());
1572 paintInfo.context().fillRect(snappedIntRect(paintRect), Color::black);
1575 void RenderBox::paintMaskImages(const PaintInfo& paintInfo, const LayoutRect& paintRect)
1577 // Figure out if we need to push a transparency layer to render our mask.
1578 bool pushTransparencyLayer = false;
1579 bool compositedMask = hasLayer() && layer()->hasCompositedMask();
1580 bool flattenCompositingLayers = view().frameView().paintBehavior() & PaintBehaviorFlattenCompositingLayers;
1581 CompositeOperator compositeOp = CompositeSourceOver;
1583 bool allMaskImagesLoaded = true;
1585 if (!compositedMask || flattenCompositingLayers) {
1586 pushTransparencyLayer = true;
1587 StyleImage* maskBoxImage = style().maskBoxImage().image();
1588 const FillLayer* maskLayers = style().maskLayers();
1590 // Don't render a masked element until all the mask images have loaded, to prevent a flash of unmasked content.
1592 allMaskImagesLoaded &= maskBoxImage->isLoaded();
1595 allMaskImagesLoaded &= maskLayers->imagesAreLoaded();
1597 paintInfo.context().setCompositeOperation(CompositeDestinationIn);
1598 paintInfo.context().beginTransparencyLayer(1);
1599 compositeOp = CompositeSourceOver;
1602 if (allMaskImagesLoaded) {
1603 paintFillLayers(paintInfo, Color(), style().maskLayers(), paintRect, BackgroundBleedNone, compositeOp);
1604 paintNinePieceImage(paintInfo.context(), paintRect, style(), style().maskBoxImage(), compositeOp);
1607 if (pushTransparencyLayer)
1608 paintInfo.context().endTransparencyLayer();
1611 LayoutRect RenderBox::maskClipRect(const LayoutPoint& paintOffset)
1613 const NinePieceImage& maskBoxImage = style().maskBoxImage();
1614 if (maskBoxImage.image()) {
1615 LayoutRect borderImageRect = borderBoxRect();
1617 // Apply outsets to the border box.
1618 borderImageRect.expand(style().maskBoxImageOutsets());
1619 return borderImageRect;
1623 LayoutRect borderBox = borderBoxRect();
1624 for (const FillLayer* maskLayer = style().maskLayers(); maskLayer; maskLayer = maskLayer->next()) {
1625 if (maskLayer->image()) {
1626 // Masks should never have fixed attachment, so it's OK for paintContainer to be null.
1627 BackgroundImageGeometry geometry = calculateBackgroundImageGeometry(nullptr, *maskLayer, paintOffset, borderBox);
1628 result.unite(geometry.destRect());
1634 void RenderBox::paintFillLayers(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, const LayoutRect& rect,
1635 BackgroundBleedAvoidance bleedAvoidance, CompositeOperator op, RenderElement* backgroundObject)
1637 Vector<const FillLayer*, 8> layers;
1638 const FillLayer* curLayer = fillLayer;
1639 bool shouldDrawBackgroundInSeparateBuffer = false;
1641 layers.append(curLayer);
1642 // Stop traversal when an opaque layer is encountered.
1643 // FIXME : It would be possible for the following occlusion culling test to be more aggressive
1644 // on layers with no repeat by testing whether the image covers the layout rect.
1645 // Testing that here would imply duplicating a lot of calculations that are currently done in
1646 // RenderBoxModelObject::paintFillLayerExtended. A more efficient solution might be to move
1647 // the layer recursion into paintFillLayerExtended, or to compute the layer geometry here
1648 // and pass it down.
1650 if (!shouldDrawBackgroundInSeparateBuffer && curLayer->blendMode() != BlendModeNormal)
1651 shouldDrawBackgroundInSeparateBuffer = true;
1653 // The clipOccludesNextLayers condition must be evaluated first to avoid short-circuiting.
1654 if (curLayer->clipOccludesNextLayers(curLayer == fillLayer) && curLayer->hasOpaqueImage(*this) && curLayer->image()->canRender(this, style().effectiveZoom()) && curLayer->hasRepeatXY() && curLayer->blendMode() == BlendModeNormal)
1656 curLayer = curLayer->next();
1659 GraphicsContext& context = paintInfo.context();
1660 BaseBackgroundColorUsage baseBgColorUsage = BaseBackgroundColorUse;
1662 if (shouldDrawBackgroundInSeparateBuffer) {
1663 paintFillLayer(paintInfo, c, *layers.rbegin(), rect, bleedAvoidance, op, backgroundObject, BaseBackgroundColorOnly);
1664 baseBgColorUsage = BaseBackgroundColorSkip;
1665 context.beginTransparencyLayer(1);
1668 Vector<const FillLayer*>::const_reverse_iterator topLayer = layers.rend();
1669 for (Vector<const FillLayer*>::const_reverse_iterator it = layers.rbegin(); it != topLayer; ++it)
1670 paintFillLayer(paintInfo, c, *it, rect, bleedAvoidance, op, backgroundObject, baseBgColorUsage);
1672 if (shouldDrawBackgroundInSeparateBuffer)
1673 context.endTransparencyLayer();
1676 void RenderBox::paintFillLayer(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, const LayoutRect& rect,
1677 BackgroundBleedAvoidance bleedAvoidance, CompositeOperator op, RenderElement* backgroundObject, BaseBackgroundColorUsage baseBgColorUsage)
1679 paintFillLayerExtended(paintInfo, c, fillLayer, rect, bleedAvoidance, nullptr, LayoutSize(), op, backgroundObject, baseBgColorUsage);
1682 static bool layersUseImage(WrappedImagePtr image, const FillLayer* layers)
1684 for (const FillLayer* curLayer = layers; curLayer; curLayer = curLayer->next()) {
1685 if (curLayer->image() && image == curLayer->image()->data())
1692 void RenderBox::imageChanged(WrappedImagePtr image, const IntRect*)
1697 if ((style().borderImage().image() && style().borderImage().image()->data() == image) ||
1698 (style().maskBoxImage().image() && style().maskBoxImage().image()->data() == image)) {
1703 #if ENABLE(CSS_SHAPES)
1704 ShapeValue* shapeOutsideValue = style().shapeOutside();
1705 if (!view().frameView().isInRenderTreeLayout() && isFloating() && shapeOutsideValue && shapeOutsideValue->image() && shapeOutsideValue->image()->data() == image) {
1706 ShapeOutsideInfo::ensureInfo(*this).markShapeAsDirty();
1707 markShapeOutsideDependentsForLayout();
1711 bool didFullRepaint = repaintLayerRectsForImage(image, style().backgroundLayers(), true);
1712 if (!didFullRepaint)
1713 repaintLayerRectsForImage(image, style().maskLayers(), false);
1715 if (!isComposited())
1718 if (layer()->hasCompositedMask() && layersUseImage(image, style().maskLayers()))
1719 layer()->contentChanged(MaskImageChanged);
1720 if (layersUseImage(image, style().backgroundLayers()))
1721 layer()->contentChanged(BackgroundImageChanged);
1724 bool RenderBox::repaintLayerRectsForImage(WrappedImagePtr image, const FillLayer* layers, bool drawingBackground)
1726 LayoutRect rendererRect;
1727 RenderBox* layerRenderer = nullptr;
1729 for (const FillLayer* curLayer = layers; curLayer; curLayer = curLayer->next()) {
1730 if (curLayer->image() && image == curLayer->image()->data() && curLayer->image()->canRender(this, style().effectiveZoom())) {
1731 // Now that we know this image is being used, compute the renderer and the rect if we haven't already.
1732 bool drawingRootBackground = drawingBackground && (isDocumentElementRenderer() || (isBody() && !document().documentElement()->renderer()->hasBackground()));
1733 if (!layerRenderer) {
1734 if (drawingRootBackground) {
1735 layerRenderer = &view();
1737 LayoutUnit rw = downcast<RenderView>(*layerRenderer).frameView().contentsWidth();
1738 LayoutUnit rh = downcast<RenderView>(*layerRenderer).frameView().contentsHeight();
1740 rendererRect = LayoutRect(-layerRenderer->marginLeft(),
1741 -layerRenderer->marginTop(),
1742 std::max(layerRenderer->width() + layerRenderer->horizontalMarginExtent() + layerRenderer->borderLeft() + layerRenderer->borderRight(), rw),
1743 std::max(layerRenderer->height() + layerRenderer->verticalMarginExtent() + layerRenderer->borderTop() + layerRenderer->borderBottom(), rh));
1745 layerRenderer = this;
1746 rendererRect = borderBoxRect();
1749 // FIXME: Figure out how to pass absolute position to calculateBackgroundImageGeometry (for pixel snapping)
1750 BackgroundImageGeometry geometry = layerRenderer->calculateBackgroundImageGeometry(nullptr, *curLayer, LayoutPoint(), rendererRect);
1751 if (geometry.hasNonLocalGeometry()) {
1752 // Rather than incur the costs of computing the paintContainer for renderers with fixed backgrounds
1753 // in order to get the right destRect, just repaint the entire renderer.
1754 layerRenderer->repaint();
1758 LayoutRect rectToRepaint = geometry.destRect();
1759 bool shouldClipToLayer = true;
1761 // If this is the root background layer, we may need to extend the repaintRect if the FrameView has an
1762 // extendedBackground. We should only extend the rect if it is already extending the full width or height
1763 // of the rendererRect.
1764 if (drawingRootBackground && view().frameView().hasExtendedBackgroundRectForPainting()) {
1765 shouldClipToLayer = false;
1766 IntRect extendedBackgroundRect = view().frameView().extendedBackgroundRectForPainting();
1767 if (rectToRepaint.width() == rendererRect.width()) {
1768 rectToRepaint.move(extendedBackgroundRect.x(), 0);
1769 rectToRepaint.setWidth(extendedBackgroundRect.width());
1771 if (rectToRepaint.height() == rendererRect.height()) {
1772 rectToRepaint.move(0, extendedBackgroundRect.y());
1773 rectToRepaint.setHeight(extendedBackgroundRect.height());
1777 layerRenderer->repaintRectangle(rectToRepaint, shouldClipToLayer);
1778 if (geometry.destRect() == rendererRect)
1785 bool RenderBox::pushContentsClip(PaintInfo& paintInfo, const LayoutPoint& accumulatedOffset)
1787 if (paintInfo.phase == PaintPhaseBlockBackground || paintInfo.phase == PaintPhaseSelfOutline || paintInfo.phase == PaintPhaseMask)
1790 bool isControlClip = hasControlClip();
1791 bool isOverflowClip = hasOverflowClip() && !layer()->isSelfPaintingLayer();
1793 if (!isControlClip && !isOverflowClip)
1796 if (paintInfo.phase == PaintPhaseOutline)
1797 paintInfo.phase = PaintPhaseChildOutlines;
1798 else if (paintInfo.phase == PaintPhaseChildBlockBackground) {
1799 paintInfo.phase = PaintPhaseBlockBackground;
1800 paintObject(paintInfo, accumulatedOffset);
1801 paintInfo.phase = PaintPhaseChildBlockBackgrounds;
1803 float deviceScaleFactor = document().deviceScaleFactor();
1804 FloatRect clipRect = snapRectToDevicePixels((isControlClip ? controlClipRect(accumulatedOffset) : overflowClipRect(accumulatedOffset, currentRenderNamedFlowFragment(), IgnoreOverlayScrollbarSize, paintInfo.phase)), deviceScaleFactor);
1805 paintInfo.context().save();
1806 if (style().hasBorderRadius())
1807 paintInfo.context().clipRoundedRect(style().getRoundedInnerBorderFor(LayoutRect(accumulatedOffset, size())).pixelSnappedRoundedRectForPainting(deviceScaleFactor));
1808 paintInfo.context().clip(clipRect);
1812 void RenderBox::popContentsClip(PaintInfo& paintInfo, PaintPhase originalPhase, const LayoutPoint& accumulatedOffset)
1814 ASSERT(hasControlClip() || (hasOverflowClip() && !layer()->isSelfPaintingLayer()));
1816 paintInfo.context().restore();
1817 if (originalPhase == PaintPhaseOutline) {
1818 paintInfo.phase = PaintPhaseSelfOutline;
1819 paintObject(paintInfo, accumulatedOffset);
1820 paintInfo.phase = originalPhase;
1821 } else if (originalPhase == PaintPhaseChildBlockBackground)
1822 paintInfo.phase = originalPhase;
1825 LayoutRect RenderBox::overflowClipRect(const LayoutPoint& location, RenderRegion* region, OverlayScrollbarSizeRelevancy relevancy, PaintPhase)
1827 // FIXME: When overflow-clip (CSS3) is implemented, we'll obtain the property
1829 LayoutRect clipRect = borderBoxRectInRegion(region);
1830 clipRect.setLocation(location + clipRect.location() + LayoutSize(borderLeft(), borderTop()));
1831 clipRect.setSize(clipRect.size() - LayoutSize(borderLeft() + borderRight(), borderTop() + borderBottom()));
1833 // Subtract out scrollbars if we have them.
1835 if (shouldPlaceBlockDirectionScrollbarOnLeft())
1836 clipRect.move(layer()->verticalScrollbarWidth(relevancy), 0);
1837 clipRect.contract(layer()->verticalScrollbarWidth(relevancy), layer()->horizontalScrollbarHeight(relevancy));
1843 LayoutRect RenderBox::clipRect(const LayoutPoint& location, RenderRegion* region)
1845 LayoutRect borderBoxRect = borderBoxRectInRegion(region);
1846 LayoutRect clipRect = LayoutRect(borderBoxRect.location() + location, borderBoxRect.size());
1848 if (!style().clipLeft().isAuto()) {
1849 LayoutUnit c = valueForLength(style().clipLeft(), borderBoxRect.width());
1850 clipRect.move(c, 0);
1851 clipRect.contract(c, 0);
1854 // We don't use the region-specific border box's width and height since clip offsets are (stupidly) specified
1855 // from the left and top edges. Therefore it's better to avoid constraining to smaller widths and heights.
1857 if (!style().clipRight().isAuto())
1858 clipRect.contract(width() - valueForLength(style().clipRight(), width()), 0);
1860 if (!style().clipTop().isAuto()) {
1861 LayoutUnit c = valueForLength(style().clipTop(), borderBoxRect.height());
1862 clipRect.move(0, c);
1863 clipRect.contract(0, c);
1866 if (!style().clipBottom().isAuto())
1867 clipRect.contract(0, height() - valueForLength(style().clipBottom(), height()));
1872 LayoutUnit RenderBox::shrinkLogicalWidthToAvoidFloats(LayoutUnit childMarginStart, LayoutUnit childMarginEnd, const RenderBlock& cb, RenderRegion* region) const
1874 RenderRegion* containingBlockRegion = nullptr;
1875 LayoutUnit logicalTopPosition = logicalTop();
1877 LayoutUnit offsetFromLogicalTopOfRegion = region ? region->logicalTopForFlowThreadContent() - offsetFromLogicalTopOfFirstPage() : LayoutUnit();
1878 logicalTopPosition = std::max(logicalTopPosition, logicalTopPosition + offsetFromLogicalTopOfRegion);
1879 containingBlockRegion = cb.clampToStartAndEndRegions(region);
1882 LayoutUnit logicalHeight = cb.logicalHeightForChild(*this);
1883 LayoutUnit result = cb.availableLogicalWidthForLineInRegion(logicalTopPosition, DoNotIndentText, containingBlockRegion, logicalHeight) - childMarginStart - childMarginEnd;
1885 // We need to see if margins on either the start side or the end side can contain the floats in question. If they can,
1886 // then just using the line width is inaccurate. In the case where a float completely fits, we don't need to use the line
1887 // offset at all, but can instead push all the way to the content edge of the containing block. In the case where the float
1888 // doesn't fit, we can use the line offset, but we need to grow it by the margin to reflect the fact that the margin was
1889 // "consumed" by the float. Negative margins aren't consumed by the float, and so we ignore them.
1890 if (childMarginStart > 0) {
1891 LayoutUnit startContentSide = cb.startOffsetForContent(containingBlockRegion);
1892 LayoutUnit startContentSideWithMargin = startContentSide + childMarginStart;
1893 LayoutUnit startOffset = cb.startOffsetForLineInRegion(logicalTopPosition, DoNotIndentText, containingBlockRegion, logicalHeight);
1894 if (startOffset > startContentSideWithMargin)
1895 result += childMarginStart;
1897 result += startOffset - startContentSide;
1900 if (childMarginEnd > 0) {
1901 LayoutUnit endContentSide = cb.endOffsetForContent(containingBlockRegion);
1902 LayoutUnit endContentSideWithMargin = endContentSide + childMarginEnd;
1903 LayoutUnit endOffset = cb.endOffsetForLineInRegion(logicalTopPosition, DoNotIndentText, containingBlockRegion, logicalHeight);
1904 if (endOffset > endContentSideWithMargin)
1905 result += childMarginEnd;
1907 result += endOffset - endContentSide;
1913 LayoutUnit RenderBox::containingBlockLogicalWidthForContent() const
1915 #if ENABLE(CSS_GRID_LAYOUT)
1916 if (hasOverrideContainingBlockLogicalWidth()) {
1917 if (auto overrideLogicalWidth = overrideContainingBlockContentLogicalWidth())
1918 return overrideLogicalWidth.value();
1922 if (RenderBlock* cb = containingBlock())
1923 return cb->availableLogicalWidth();
1924 return LayoutUnit();
1927 LayoutUnit RenderBox::containingBlockLogicalHeightForContent(AvailableLogicalHeightType heightType) const
1929 #if ENABLE(CSS_GRID_LAYOUT)
1930 if (hasOverrideContainingBlockLogicalHeight()) {
1931 if (auto overrideLogicalHeight = overrideContainingBlockContentLogicalHeight())
1932 return overrideLogicalHeight.value();
1936 if (RenderBlock* cb = containingBlock())
1937 return cb->availableLogicalHeight(heightType);
1938 return LayoutUnit();
1941 LayoutUnit RenderBox::containingBlockLogicalWidthForContentInRegion(RenderRegion* region) const
1944 return containingBlockLogicalWidthForContent();
1946 RenderBlock* cb = containingBlock();
1947 RenderRegion* containingBlockRegion = cb->clampToStartAndEndRegions(region);
1948 // FIXME: It's unclear if a region's content should use the containing block's override logical width.
1949 // If it should, the following line should call containingBlockLogicalWidthForContent.
1950 LayoutUnit result = cb->availableLogicalWidth();
1951 RenderBoxRegionInfo* boxInfo = cb->renderBoxRegionInfo(containingBlockRegion);
1954 return std::max<LayoutUnit>(0, result - (cb->logicalWidth() - boxInfo->logicalWidth()));
1957 LayoutUnit RenderBox::containingBlockAvailableLineWidthInRegion(RenderRegion* region) const
1959 RenderBlock* cb = containingBlock();
1960 RenderRegion* containingBlockRegion = nullptr;
1961 LayoutUnit logicalTopPosition = logicalTop();
1963 LayoutUnit offsetFromLogicalTopOfRegion = region ? region->logicalTopForFlowThreadContent() - offsetFromLogicalTopOfFirstPage() : LayoutUnit();
1964 logicalTopPosition = std::max(logicalTopPosition, logicalTopPosition + offsetFromLogicalTopOfRegion);
1965 containingBlockRegion = cb->clampToStartAndEndRegions(region);
1967 return cb->availableLogicalWidthForLineInRegion(logicalTopPosition, DoNotIndentText, containingBlockRegion, availableLogicalHeight(IncludeMarginBorderPadding));
1970 LayoutUnit RenderBox::perpendicularContainingBlockLogicalHeight() const
1972 #if ENABLE(CSS_GRID_LAYOUT)
1973 if (hasOverrideContainingBlockLogicalHeight()) {
1974 if (auto overrideLogicalHeight = overrideContainingBlockContentLogicalHeight())
1975 return overrideLogicalHeight.value();
1979 RenderBlock* cb = containingBlock();
1980 if (cb->hasOverrideLogicalContentHeight())
1981 return cb->overrideLogicalContentHeight();
1983 const RenderStyle& containingBlockStyle = cb->style();
1984 Length logicalHeightLength = containingBlockStyle.logicalHeight();
1986 // FIXME: For now just support fixed heights. Eventually should support percentage heights as well.
1987 if (!logicalHeightLength.isFixed()) {
1988 LayoutUnit fillFallbackExtent = containingBlockStyle.isHorizontalWritingMode() ? view().frameView().visibleHeight() : view().frameView().visibleWidth();
1989 LayoutUnit fillAvailableExtent = containingBlock()->availableLogicalHeight(ExcludeMarginBorderPadding);
1990 return std::min(fillAvailableExtent, fillFallbackExtent);
1993 // Use the content box logical height as specified by the style.
1994 return cb->adjustContentBoxLogicalHeightForBoxSizing(LayoutUnit(logicalHeightLength.value()));
1997 void RenderBox::mapLocalToContainer(const RenderLayerModelObject* repaintContainer, TransformState& transformState, MapCoordinatesFlags mode, bool* wasFixed) const
1999 if (repaintContainer == this)
2002 if (view().layoutStateEnabled() && !repaintContainer) {
2003 LayoutState* layoutState = view().layoutState();
2004 LayoutSize offset = layoutState->m_paintOffset + locationOffset();
2005 if (style().hasInFlowPosition() && layer())
2006 offset += layer()->offsetForInFlowPosition();
2007 transformState.move(offset);
2011 bool containerSkipped;
2012 RenderElement* container = this->container(repaintContainer, containerSkipped);
2016 bool isFixedPos = style().position() == FixedPosition;
2017 // If this box has a transform, it acts as a fixed position container for fixed descendants,
2018 // and may itself also be fixed position. So propagate 'fixed' up only if this box is fixed position.
2019 if (hasTransform() && !isFixedPos)
2021 else if (isFixedPos)
2025 *wasFixed = mode & IsFixed;
2027 LayoutSize containerOffset = offsetFromContainer(*container, LayoutPoint(transformState.mappedPoint()));
2029 bool preserve3D = mode & UseTransforms && (container->style().preserves3D() || style().preserves3D());
2030 if (mode & UseTransforms && shouldUseTransformFromContainer(container)) {
2031 TransformationMatrix t;
2032 getTransformFromContainer(container, containerOffset, t);
2033 transformState.applyTransform(t, preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
2035 transformState.move(containerOffset.width(), containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
2037 if (containerSkipped) {
2038 // There can't be a transform between repaintContainer and o, because transforms create containers, so it should be safe
2039 // to just subtract the delta between the repaintContainer and o.
2040 LayoutSize containerOffset = repaintContainer->offsetFromAncestorContainer(*container);
2041 transformState.move(-containerOffset.width(), -containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
2045 mode &= ~ApplyContainerFlip;
2047 // For fixed positioned elements inside out-of-flow named flows, we do not want to
2048 // map their position further to regions based on their coordinates inside the named flows.
2049 if (!container->isOutOfFlowRenderFlowThread() || !fixedPositionedWithNamedFlowContainingBlock())
2050 container->mapLocalToContainer(repaintContainer, transformState, mode, wasFixed);
2052 container->mapLocalToContainer(downcast<RenderLayerModelObject>(container), transformState, mode, wasFixed);
2055 const RenderObject* RenderBox::pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap& geometryMap) const
2057 ASSERT(ancestorToStopAt != this);
2059 bool ancestorSkipped;
2060 RenderElement* container = this->container(ancestorToStopAt, ancestorSkipped);
2064 bool isFixedPos = style().position() == FixedPosition;
2065 LayoutSize adjustmentForSkippedAncestor;
2066 if (ancestorSkipped) {
2067 // There can't be a transform between repaintContainer and container, because transforms create containers, so it should be safe
2068 // to just subtract the delta between the ancestor and container.
2069 adjustmentForSkippedAncestor = -ancestorToStopAt->offsetFromAncestorContainer(*container);
2072 bool offsetDependsOnPoint = false;
2073 LayoutSize containerOffset = offsetFromContainer(*container, LayoutPoint(), &offsetDependsOnPoint);
2075 bool preserve3D = container->style().preserves3D() || style().preserves3D();
2076 if (shouldUseTransformFromContainer(container) && (geometryMap.mapCoordinatesFlags() & UseTransforms)) {
2077 TransformationMatrix t;
2078 getTransformFromContainer(container, containerOffset, t);
2079 t.translateRight(adjustmentForSkippedAncestor.width(), adjustmentForSkippedAncestor.height());
2081 geometryMap.push(this, t, preserve3D, offsetDependsOnPoint, isFixedPos, hasTransform());
2083 containerOffset += adjustmentForSkippedAncestor;
2084 geometryMap.push(this, containerOffset, preserve3D, offsetDependsOnPoint, isFixedPos, hasTransform());
2087 return ancestorSkipped ? ancestorToStopAt : container;
2090 void RenderBox::mapAbsoluteToLocalPoint(MapCoordinatesFlags mode, TransformState& transformState) const
2092 bool isFixedPos = style().position() == FixedPosition;
2093 if (hasTransform() && !isFixedPos) {
2094 // If this box has a transform, it acts as a fixed position container for fixed descendants,
2095 // and may itself also be fixed position. So propagate 'fixed' up only if this box is fixed position.
2097 } else if (isFixedPos)
2100 RenderBoxModelObject::mapAbsoluteToLocalPoint(mode, transformState);
2103 LayoutSize RenderBox::offsetFromContainer(RenderElement& renderer, const LayoutPoint&, bool* offsetDependsOnPoint) const
2105 // A region "has" boxes inside it without being their container.
2106 ASSERT(&renderer == container() || is<RenderRegion>(renderer));
2109 if (isInFlowPositioned())
2110 offset += offsetForInFlowPosition();
2112 if (!isInline() || isReplaced())
2113 offset += topLeftLocationOffset();
2115 if (is<RenderBox>(renderer))
2116 offset -= toLayoutSize(downcast<RenderBox>(renderer).scrollPosition());
2118 if (style().position() == AbsolutePosition && renderer.isInFlowPositioned() && is<RenderInline>(renderer))
2119 offset += downcast<RenderInline>(renderer).offsetForInFlowPositionedInline(this);
2121 if (offsetDependsOnPoint)
2122 *offsetDependsOnPoint |= is<RenderFlowThread>(renderer);
2127 std::unique_ptr<InlineElementBox> RenderBox::createInlineBox()
2129 return std::make_unique<InlineElementBox>(*this);
2132 void RenderBox::dirtyLineBoxes(bool fullLayout)
2134 if (m_inlineBoxWrapper) {
2136 delete m_inlineBoxWrapper;
2137 m_inlineBoxWrapper = nullptr;
2139 m_inlineBoxWrapper->dirtyLineBoxes();
2143 void RenderBox::positionLineBox(InlineElementBox& box)
2145 if (isOutOfFlowPositioned()) {
2146 // Cache the x position only if we were an INLINE type originally.
2147 bool wasInline = style().isOriginalDisplayInlineType();
2149 // The value is cached in the xPos of the box. We only need this value if
2150 // our object was inline originally, since otherwise it would have ended up underneath
2152 RootInlineBox& rootBox = box.root();
2153 rootBox.blockFlow().setStaticInlinePositionForChild(*this, rootBox.lineTopWithLeading(), LayoutUnit::fromFloatRound(box.logicalLeft()));
2154 if (style().hasStaticInlinePosition(box.isHorizontal()))
2155 setChildNeedsLayout(MarkOnlyThis); // Just mark the positioned object as needing layout, so it will update its position properly.
2157 // Our object was a block originally, so we make our normal flow position be
2158 // just below the line box (as though all the inlines that came before us got
2159 // wrapped in an anonymous block, which is what would have happened had we been
2160 // in flow). This value was cached in the y() of the box.
2161 layer()->setStaticBlockPosition(box.logicalTop());
2162 if (style().hasStaticBlockPosition(box.isHorizontal()))
2163 setChildNeedsLayout(MarkOnlyThis); // Just mark the positioned object as needing layout, so it will update its position properly.
2169 setLocation(LayoutPoint(box.topLeft()));
2170 setInlineBoxWrapper(&box);
2174 void RenderBox::deleteLineBoxWrapper()
2176 if (m_inlineBoxWrapper) {
2177 if (!documentBeingDestroyed())
2178 m_inlineBoxWrapper->removeFromParent();
2179 delete m_inlineBoxWrapper;
2180 m_inlineBoxWrapper = nullptr;
2184 LayoutRect RenderBox::clippedOverflowRectForRepaint(const RenderLayerModelObject* repaintContainer) const
2186 if (style().visibility() != VISIBLE && !enclosingLayer()->hasVisibleContent())
2187 return LayoutRect();
2188 LayoutRect r = visualOverflowRect();
2189 // FIXME: layoutDelta needs to be applied in parts before/after transforms and
2190 // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
2191 r.move(view().layoutDelta());
2192 return computeRectForRepaint(r, repaintContainer);
2195 static inline bool shouldApplyContainersClipAndOffset(const RenderLayerModelObject* repaintContainer, RenderBox* containerBox)
2198 if (!repaintContainer || repaintContainer != containerBox)
2201 return !containerBox->hasLayer() || !containerBox->layer()->usesCompositedScrolling();
2203 UNUSED_PARAM(repaintContainer);
2204 UNUSED_PARAM(containerBox);
2209 LayoutRect RenderBox::computeRectForRepaint(const LayoutRect& rect, const RenderLayerModelObject* repaintContainer, bool fixed) const
2211 // The rect we compute at each step is shifted by our x/y offset in the parent container's coordinate space.
2212 // Only when we cross a writing mode boundary will we have to possibly flipForWritingMode (to convert into a more appropriate
2213 // offset corner for the enclosing container). This allows for a fully RL or BT document to repaint
2214 // properly even during layout, since the rect remains flipped all the way until the end.
2216 // RenderView::computeRectForRepaint then converts the rect to physical coordinates. We also convert to
2217 // physical when we hit a repaintContainer boundary. Therefore the final rect returned is always in the
2218 // physical coordinate space of the repaintContainer.
2219 LayoutRect adjustedRect = rect;
2220 const RenderStyle& styleToUse = style();
2221 // LayoutState is only valid for root-relative, non-fixed position repainting
2222 if (view().layoutStateEnabled() && !repaintContainer && styleToUse.position() != FixedPosition) {
2223 LayoutState* layoutState = view().layoutState();
2225 if (layer() && layer()->transform())
2226 adjustedRect = LayoutRect(encloseRectToDevicePixels(layer()->transform()->mapRect(adjustedRect), document().deviceScaleFactor()));
2228 // We can't trust the bits on RenderObject, because this might be called while re-resolving style.
2229 if (styleToUse.hasInFlowPosition() && layer())
2230 adjustedRect.move(layer()->offsetForInFlowPosition());
2232 adjustedRect.moveBy(location());
2233 adjustedRect.move(layoutState->m_paintOffset);
2234 if (layoutState->m_clipped)
2235 adjustedRect.intersect(layoutState->m_clipRect);
2236 return adjustedRect;
2239 if (hasReflection())
2240 adjustedRect.unite(reflectedRect(adjustedRect));
2242 if (repaintContainer == this) {
2243 if (repaintContainer->style().isFlippedBlocksWritingMode())
2244 flipForWritingMode(adjustedRect);
2245 return adjustedRect;
2248 bool containerSkipped;
2249 auto* renderer = container(repaintContainer, containerSkipped);
2251 return adjustedRect;
2253 EPosition position = styleToUse.position();
2255 // This code isn't necessary for in-flow RenderFlowThreads.
2256 // Don't add the location of the region in the flow thread for absolute positioned
2257 // elements because their absolute position already pushes them down through
2258 // the regions so adding this here and then adding the topLeft again would cause
2259 // us to add the height twice.
2260 // The same logic applies for elements flowed directly into the flow thread. Their topLeft member
2261 // will already contain the portion rect of the region.
2262 if (renderer->isOutOfFlowRenderFlowThread() && position != AbsolutePosition && containingBlock() != flowThreadContainingBlock()) {
2263 RenderRegion* firstRegion = nullptr;
2264 RenderRegion* lastRegion = nullptr;
2265 if (downcast<RenderFlowThread>(*renderer).getRegionRangeForBox(this, firstRegion, lastRegion))
2266 adjustedRect.moveBy(firstRegion->flowThreadPortionRect().location());
2269 if (isWritingModeRoot() && !isOutOfFlowPositioned())
2270 flipForWritingMode(adjustedRect);
2272 LayoutSize locationOffset = this->locationOffset();
2273 // FIXME: This is needed as long as RenderWidget snaps to integral size/position.
2274 if (isRenderReplaced() && isWidget()) {
2275 LayoutSize flooredLocationOffset = toIntSize(flooredIntPoint(locationOffset));
2276 adjustedRect.expand(locationOffset - flooredLocationOffset);
2277 locationOffset = flooredLocationOffset;
2279 LayoutPoint topLeft = adjustedRect.location();
2280 topLeft.move(locationOffset);
2282 // We are now in our parent container's coordinate space. Apply our transform to obtain a bounding box
2283 // in the parent's coordinate space that encloses us.
2284 if (hasLayer() && layer()->transform()) {
2285 fixed = position == FixedPosition;
2286 adjustedRect = LayoutRect(encloseRectToDevicePixels(layer()->transform()->mapRect(adjustedRect), document().deviceScaleFactor()));
2287 topLeft = adjustedRect.location();
2288 topLeft.move(locationOffset);
2289 } else if (position == FixedPosition)
2292 if (position == AbsolutePosition && renderer->isInFlowPositioned() && is<RenderInline>(*renderer))
2293 topLeft += downcast<RenderInline>(*renderer).offsetForInFlowPositionedInline(this);
2294 else if (styleToUse.hasInFlowPosition() && layer()) {
2295 // Apply the relative position offset when invalidating a rectangle. The layer
2296 // is translated, but the render box isn't, so we need to do this to get the
2297 // right dirty rect. Since this is called from RenderObject::setStyle, the relative position
2298 // flag on the RenderObject has been cleared, so use the one on the style().
2299 topLeft += layer()->offsetForInFlowPosition();
2302 // FIXME: We ignore the lightweight clipping rect that controls use, since if |o| is in mid-layout,
2303 // its controlClipRect will be wrong. For overflow clip we use the values cached by the layer.
2304 adjustedRect.setLocation(topLeft);
2305 if (renderer->hasOverflowClip()) {
2306 RenderBox& containerBox = downcast<RenderBox>(*renderer);
2307 if (shouldApplyContainersClipAndOffset(repaintContainer, &containerBox)) {
2308 containerBox.applyCachedClipAndScrollOffsetForRepaint(adjustedRect);
2309 if (adjustedRect.isEmpty())
2310 return adjustedRect;
2314 if (containerSkipped) {
2315 // If the repaintContainer is below o, then we need to map the rect into repaintContainer's coordinates.
2316 LayoutSize containerOffset = repaintContainer->offsetFromAncestorContainer(*renderer);
2317 adjustedRect.move(-containerOffset);
2318 return adjustedRect;
2320 return renderer->computeRectForRepaint(adjustedRect, repaintContainer, fixed);
2323 void RenderBox::repaintDuringLayoutIfMoved(const LayoutRect& oldRect)
2325 if (oldRect.location() != m_frameRect.location()) {
2326 LayoutRect newRect = m_frameRect;
2327 // The child moved. Invalidate the object's old and new positions. We have to do this
2328 // since the object may not have gotten a layout.
2329 m_frameRect = oldRect;
2331 repaintOverhangingFloats(true);
2332 m_frameRect = newRect;
2334 repaintOverhangingFloats(true);
2338 void RenderBox::repaintOverhangingFloats(bool)
2342 void RenderBox::updateLogicalWidth()
2344 LogicalExtentComputedValues computedValues;
2345 computeLogicalWidthInRegion(computedValues);
2347 setLogicalWidth(computedValues.m_extent);
2348 setLogicalLeft(computedValues.m_position);
2349 setMarginStart(computedValues.m_margins.m_start);
2350 setMarginEnd(computedValues.m_margins.m_end);
2353 void RenderBox::computeLogicalWidthInRegion(LogicalExtentComputedValues& computedValues, RenderRegion* region) const
2355 computedValues.m_extent = logicalWidth();
2356 computedValues.m_position = logicalLeft();
2357 computedValues.m_margins.m_start = marginStart();
2358 computedValues.m_margins.m_end = marginEnd();
2360 if (isOutOfFlowPositioned()) {
2361 // FIXME: This calculation is not patched for block-flow yet.
2362 // https://bugs.webkit.org/show_bug.cgi?id=46500
2363 computePositionedLogicalWidth(computedValues, region);
2367 // If layout is limited to a subtree, the subtree root's logical width does not change.
2368 if (element() && !view().frameView().layoutPending() && view().frameView().layoutRoot() == this)
2371 // The parent box is flexing us, so it has increased or decreased our
2372 // width. Use the width from the style context.
2373 // FIXME: Account for block-flow in flexible boxes.
2374 // https://bugs.webkit.org/show_bug.cgi?id=46418
2375 if (hasOverrideLogicalContentWidth() && (isRubyRun() || style().borderFit() == BorderFitLines || (parent()->isFlexibleBoxIncludingDeprecated()))) {
2376 computedValues.m_extent = overrideLogicalContentWidth() + borderAndPaddingLogicalWidth();
2380 // FIXME: Account for block-flow in flexible boxes.
2381 // https://bugs.webkit.org/show_bug.cgi?id=46418
2382 bool inVerticalBox = parent()->isDeprecatedFlexibleBox() && (parent()->style().boxOrient() == VERTICAL);
2383 bool stretching = (parent()->style().boxAlign() == BSTRETCH);
2384 // FIXME: Stretching is the only reason why we don't want the box to be treated as a replaced element, so we could perhaps
2385 // refactor all this logic, not only for flex and grid since alignment is intended to be applied to any block.
2386 bool treatAsReplaced = shouldComputeSizeAsReplaced() && (!inVerticalBox || !stretching);
2387 #if ENABLE(CSS_GRID_LAYOUT)
2388 treatAsReplaced = treatAsReplaced && (!isGridItem() || !hasStretchedLogicalWidth());
2391 const RenderStyle& styleToUse = style();
2392 Length logicalWidthLength = treatAsReplaced ? Length(computeReplacedLogicalWidth(), Fixed) : styleToUse.logicalWidth();
2394 RenderBlock& cb = *containingBlock();
2395 LayoutUnit containerLogicalWidth = std::max<LayoutUnit>(0, containingBlockLogicalWidthForContentInRegion(region));
2396 bool hasPerpendicularContainingBlock = cb.isHorizontalWritingMode() != isHorizontalWritingMode();
2398 if (isInline() && !isInlineBlockOrInlineTable()) {
2399 // just calculate margins
2400 computedValues.m_margins.m_start = minimumValueForLength(styleToUse.marginStart(), containerLogicalWidth);
2401 computedValues.m_margins.m_end = minimumValueForLength(styleToUse.marginEnd(), containerLogicalWidth);
2402 if (treatAsReplaced)
2403 computedValues.m_extent = std::max<LayoutUnit>(floatValueForLength(logicalWidthLength, 0) + borderAndPaddingLogicalWidth(), minPreferredLogicalWidth());
2407 // Width calculations
2408 if (treatAsReplaced) {
2409 computedValues.m_extent = logicalWidthLength.value() + borderAndPaddingLogicalWidth();
2410 #if ENABLE(CSS_GRID_LAYOUT)
2411 } else if (parent()->isRenderGrid() && style().logicalWidth().isAuto() && style().logicalMinWidth().isAuto() && style().overflowX() == OVISIBLE && containerLogicalWidth < minPreferredLogicalWidth()) {
2412 // TODO (lajava) Move this logic to the LayoutGrid class.
2413 // Implied minimum size of Grid items.
2414 computedValues.m_extent = constrainLogicalWidthInRegionByMinMax(minPreferredLogicalWidth(), containerLogicalWidth, cb);
2417 LayoutUnit containerWidthInInlineDirection = containerLogicalWidth;
2418 if (hasPerpendicularContainingBlock)
2419 containerWidthInInlineDirection = perpendicularContainingBlockLogicalHeight();
2420 LayoutUnit preferredWidth = computeLogicalWidthInRegionUsing(MainOrPreferredSize, styleToUse.logicalWidth(), containerWidthInInlineDirection, cb, region);
2421 computedValues.m_extent = constrainLogicalWidthInRegionByMinMax(preferredWidth, containerWidthInInlineDirection, cb, region);
2424 // Margin calculations.
2425 if (hasPerpendicularContainingBlock || isFloating() || isInline()) {
2426 computedValues.m_margins.m_start = minimumValueForLength(styleToUse.marginStart(), containerLogicalWidth);
2427 computedValues.m_margins.m_end = minimumValueForLength(styleToUse.marginEnd(), containerLogicalWidth);
2429 LayoutUnit containerLogicalWidthForAutoMargins = containerLogicalWidth;
2430 if (avoidsFloats() && cb.containsFloats())
2431 containerLogicalWidthForAutoMargins = containingBlockAvailableLineWidthInRegion(region);
2432 bool hasInvertedDirection = cb.style().isLeftToRightDirection() != style().isLeftToRightDirection();
2433 computeInlineDirectionMargins(cb, containerLogicalWidthForAutoMargins, computedValues.m_extent,
2434 hasInvertedDirection ? computedValues.m_margins.m_end : computedValues.m_margins.m_start,
2435 hasInvertedDirection ? computedValues.m_margins.m_start : computedValues.m_margins.m_end);
2438 if (!hasPerpendicularContainingBlock && containerLogicalWidth && containerLogicalWidth != (computedValues.m_extent + computedValues.m_margins.m_start + computedValues.m_margins.m_end)
2439 && !isFloating() && !isInline() && !cb.isFlexibleBoxIncludingDeprecated()
2440 #if ENABLE(CSS_GRID_LAYOUT)
2441 && !cb.isRenderGrid()
2444 LayoutUnit newMargin = containerLogicalWidth - computedValues.m_extent - cb.marginStartForChild(*this);
2445 bool hasInvertedDirection = cb.style().isLeftToRightDirection() != style().isLeftToRightDirection();
2446 if (hasInvertedDirection)
2447 computedValues.m_margins.m_start = newMargin;
2449 computedValues.m_margins.m_end = newMargin;
2453 LayoutUnit RenderBox::fillAvailableMeasure(LayoutUnit availableLogicalWidth) const
2455 LayoutUnit marginStart = 0;
2456 LayoutUnit marginEnd = 0;
2457 return fillAvailableMeasure(availableLogicalWidth, marginStart, marginEnd);
2460 LayoutUnit RenderBox::fillAvailableMeasure(LayoutUnit availableLogicalWidth, LayoutUnit& marginStart, LayoutUnit& marginEnd) const
2462 marginStart = minimumValueForLength(style().marginStart(), availableLogicalWidth);
2463 marginEnd = minimumValueForLength(style().marginEnd(), availableLogicalWidth);
2464 return availableLogicalWidth - marginStart - marginEnd;
2467 LayoutUnit RenderBox::computeIntrinsicLogicalWidthUsing(Length logicalWidthLength, LayoutUnit availableLogicalWidth, LayoutUnit borderAndPadding) const
2469 if (logicalWidthLength.type() == FillAvailable)
2470 return fillAvailableMeasure(availableLogicalWidth);
2472 LayoutUnit minLogicalWidth = 0;
2473 LayoutUnit maxLogicalWidth = 0;
2474 computeIntrinsicLogicalWidths(minLogicalWidth, maxLogicalWidth);
2476 if (logicalWidthLength.type() == MinContent)
2477 return minLogicalWidth + borderAndPadding;
2479 if (logicalWidthLength.type() == MaxContent)
2480 return maxLogicalWidth + borderAndPadding;
2482 if (logicalWidthLength.type() == FitContent) {
2483 minLogicalWidth += borderAndPadding;
2484 maxLogicalWidth += borderAndPadding;
2485 return std::max(minLogicalWidth, std::min(maxLogicalWidth, fillAvailableMeasure(availableLogicalWidth)));
2488 ASSERT_NOT_REACHED();
2492 LayoutUnit RenderBox::computeLogicalWidthInRegionUsing(SizeType widthType, Length logicalWidth, LayoutUnit availableLogicalWidth,
2493 const RenderBlock& cb, RenderRegion* region) const
2495 ASSERT(widthType == MinSize || widthType == MainOrPreferredSize || !logicalWidth.isAuto());
2496 if (widthType == MinSize && logicalWidth.isAuto())
2497 return adjustBorderBoxLogicalWidthForBoxSizing(0);
2499 if (!logicalWidth.isIntrinsicOrAuto()) {
2500 // FIXME: If the containing block flow is perpendicular to our direction we need to use the available logical height instead.
2501 return adjustBorderBoxLogicalWidthForBoxSizing(valueForLength(logicalWidth, availableLogicalWidth));
2504 if (logicalWidth.isIntrinsic())
2505 return computeIntrinsicLogicalWidthUsing(logicalWidth, availableLogicalWidth, borderAndPaddingLogicalWidth());
2507 LayoutUnit marginStart = 0;
2508 LayoutUnit marginEnd = 0;
2509 LayoutUnit logicalWidthResult = fillAvailableMeasure(availableLogicalWidth, marginStart, marginEnd);
2511 if (shrinkToAvoidFloats() && cb.containsFloats())
2512 logicalWidthResult = std::min(logicalWidthResult, shrinkLogicalWidthToAvoidFloats(marginStart, marginEnd, cb, region));
2514 if (widthType == MainOrPreferredSize && sizesLogicalWidthToFitContent(widthType))
2515 return std::max(minPreferredLogicalWidth(), std::min(maxPreferredLogicalWidth(), logicalWidthResult));
2516 return logicalWidthResult;
2519 static bool flexItemHasStretchAlignment(const RenderBox& flexitem)
2521 auto parent = flexitem.parent();
2522 return flexitem.style().resolvedAlignSelf(parent->style(), ItemPositionStretch).position() == ItemPositionStretch;
2525 static bool isStretchingColumnFlexItem(const RenderBox& flexitem)
2527 auto parent = flexitem.parent();
2528 if (parent->isDeprecatedFlexibleBox() && parent->style().boxOrient() == VERTICAL && parent->style().boxAlign() == BSTRETCH)
2531 // We don't stretch multiline flexboxes because they need to apply line spacing (align-content) first.
2532 if (parent->isFlexibleBox() && parent->style().flexWrap() == FlexNoWrap && parent->style().isColumnFlexDirection() && flexItemHasStretchAlignment(flexitem))
2537 // FIXME: Can/Should we move this inside specific layout classes (flex. grid)? Can we refactor columnFlexItemHasStretchAlignment logic?
2538 bool RenderBox::hasStretchedLogicalWidth() const
2540 auto& style = this->style();
2541 if (!style.logicalWidth().isAuto() || style.marginStart().isAuto() || style.marginEnd().isAuto())
2543 RenderBlock* containingBlock = this->containingBlock();
2544 if (!containingBlock) {
2545 // We are evaluating align-self/justify-self, which default to 'normal' for the root element.
2546 // The 'normal' value behaves like 'start' except for Flexbox Items, which obviously should have a container.
2549 if (containingBlock->isHorizontalWritingMode() != isHorizontalWritingMode())
2550 return style.resolvedAlignSelf(containingBlock->style(), ItemPositionStretch).position() == ItemPositionStretch;
2551 return style.resolvedJustifySelf(containingBlock->style(), ItemPositionStretch).position() == ItemPositionStretch;
2554 bool RenderBox::sizesLogicalWidthToFitContent(SizeType widthType) const
2556 // Anonymous inline blocks always fill the width of their containing block.
2557 if (isAnonymousInlineBlock())
2560 // Marquees in WinIE are like a mixture of blocks and inline-blocks. They size as though they're blocks,
2561 // but they allow text to sit on the same line as the marquee.
2562 if (isFloating() || (isInlineBlockOrInlineTable() && !isHTMLMarquee()))
2565 #if ENABLE(CSS_GRID_LAYOUT)
2567 return !hasStretchedLogicalWidth();
2570 // This code may look a bit strange. Basically width:intrinsic should clamp the size when testing both
2571 // min-width and width. max-width is only clamped if it is also intrinsic.
2572 Length logicalWidth = (widthType == MaxSize) ? style().logicalMaxWidth() : style().logicalWidth();
2573 if (logicalWidth.type() == Intrinsic)
2576 // Children of a horizontal marquee do not fill the container by default.
2577 // FIXME: Need to deal with MAUTO value properly. It could be vertical.
2578 // FIXME: Think about block-flow here. Need to find out how marquee direction relates to
2579 // block-flow (as well as how marquee overflow should relate to block flow).
2580 // https://bugs.webkit.org/show_bug.cgi?id=46472
2581 if (parent()->isHTMLMarquee()) {
2582 EMarqueeDirection dir = parent()->style().marqueeDirection();
2583 if (dir == MAUTO || dir == MFORWARD || dir == MBACKWARD || dir == MLEFT || dir == MRIGHT)
2587 // Flexible box items should shrink wrap, so we lay them out at their intrinsic widths.
2588 // In the case of columns that have a stretch alignment, we layout at the stretched size
2589 // to avoid an extra layout when applying alignment.
2590 if (parent()->isFlexibleBox()) {
2591 // For multiline columns, we need to apply align-content first, so we can't stretch now.
2592 if (!parent()->style().isColumnFlexDirection() || parent()->style().flexWrap() != FlexNoWrap)
2594 if (!flexItemHasStretchAlignment(*this))
2598 // Flexible horizontal boxes lay out children at their intrinsic widths. Also vertical boxes
2599 // that don't stretch their kids lay out their children at their intrinsic widths.
2600 // FIXME: Think about block-flow here.
2601 // https://bugs.webkit.org/show_bug.cgi?id=46473
2602 if (parent()->isDeprecatedFlexibleBox() && (parent()->style().boxOrient() == HORIZONTAL || parent()->style().boxAlign() != BSTRETCH))
2605 // Button, input, select, textarea, and legend treat width value of 'auto' as 'intrinsic' unless it's in a
2606 // stretching column flexbox.
2607 // FIXME: Think about block-flow here.
2608 // https://bugs.webkit.org/show_bug.cgi?id=46473
2609 if (logicalWidth.type() == Auto && !isStretchingColumnFlexItem(*this) && element() && (is<HTMLInputElement>(*element()) || is<HTMLSelectElement>(*element()) || is<HTMLButtonElement>(*element()) || is<HTMLTextAreaElement>(*element()) || is<HTMLLegendElement>(*element())))
2612 if (isHorizontalWritingMode() != containingBlock()->isHorizontalWritingMode())
2618 void RenderBox::computeInlineDirectionMargins(const RenderBlock& containingBlock, LayoutUnit containerWidth, LayoutUnit childWidth, LayoutUnit& marginStart, LayoutUnit& marginEnd) const
2620 const RenderStyle& containingBlockStyle = containingBlock.style();
2621 Length marginStartLength = style().marginStartUsing(&containingBlockStyle);
2622 Length marginEndLength = style().marginEndUsing(&containingBlockStyle);
2624 if (isFloating() || isInline()) {
2625 // Inline blocks/tables and floats don't have their margins increased.
2626 marginStart = minimumValueForLength(marginStartLength, containerWidth);
2627 marginEnd = minimumValueForLength(marginEndLength, containerWidth);
2631 // Case One: The object is being centered in the containing block's available logical width.
2632 if ((marginStartLength.isAuto() && marginEndLength.isAuto() && childWidth < containerWidth)
2633 || (!marginStartLength.isAuto() && !marginEndLength.isAuto() && containingBlock.style().textAlign() == WEBKIT_CENTER)) {
2634 // Other browsers center the margin box for align=center elements so we match them here.
2635 LayoutUnit marginStartWidth = minimumValueForLength(marginStartLength, containerWidth);
2636 LayoutUnit marginEndWidth = minimumValueForLength(marginEndLength, containerWidth);
2637 LayoutUnit centeredMarginBoxStart = std::max<LayoutUnit>(0, (containerWidth - childWidth - marginStartWidth - marginEndWidth) / 2);
2638 marginStart = centeredMarginBoxStart + marginStartWidth;
2639 marginEnd = containerWidth - childWidth - marginStart + marginEndWidth;
2643 // Case Two: The object is being pushed to the start of the containing block's available logical width.
2644 if (marginEndLength.isAuto() && childWidth < containerWidth) {
2645 marginStart = valueForLength(marginStartLength, containerWidth);
2646 marginEnd = containerWidth - childWidth - marginStart;
2650 // Case Three: The object is being pushed to the end of the containing block's available logical width.
2651 bool pushToEndFromTextAlign = !marginEndLength.isAuto() && ((!containingBlockStyle.isLeftToRightDirection() && containingBlockStyle.textAlign() == WEBKIT_LEFT)
2652 || (containingBlockStyle.isLeftToRightDirection() && containingBlockStyle.textAlign() == WEBKIT_RIGHT));
2653 if ((marginStartLength.isAuto() && childWidth < containerWidth) || pushToEndFromTextAlign) {
2654 marginEnd = valueForLength(marginEndLength, containerWidth);
2655 marginStart = containerWidth - childWidth - marginEnd;
2659 // Case Four: Either no auto margins, or our width is >= the container width (css2.1, 10.3.3). In that case
2660 // auto margins will just turn into 0.
2661 marginStart = minimumValueForLength(marginStartLength, containerWidth);
2662 marginEnd = minimumValueForLength(marginEndLength, containerWidth);
2665 RenderBoxRegionInfo* RenderBox::renderBoxRegionInfo(RenderRegion* region, RenderBoxRegionInfoFlags cacheFlag) const
2667 // Make sure nobody is trying to call this with a null region.
2671 // If we have computed our width in this region already, it will be cached, and we can
2673 RenderBoxRegionInfo* boxInfo = region->renderBoxRegionInfo(this);
2674 if (boxInfo && cacheFlag == CacheRenderBoxRegionInfo)
2677 // No cached value was found, so we have to compute our insets in this region.
2678 // FIXME: For now we limit this computation to normal RenderBlocks. Future patches will expand
2679 // support to cover all boxes.
2680 RenderFlowThread* flowThread = flowThreadContainingBlock();
2681 if (isRenderFlowThread() || !flowThread || !canHaveBoxInfoInRegion() || flowThread->style().writingMode() != style().writingMode())
2684 LogicalExtentComputedValues computedValues;
2685 computeLogicalWidthInRegion(computedValues, region);
2687 // Now determine the insets based off where this object is supposed to be positioned.
2688 RenderBlock& cb = *containingBlock();
2689 RenderRegion* clampedContainingBlockRegion = cb.clampToStartAndEndRegions(region);
2690 RenderBoxRegionInfo* containingBlockInfo = cb.renderBoxRegionInfo(clampedContainingBlockRegion);
2691 LayoutUnit containingBlockLogicalWidth = cb.logicalWidth();
2692 LayoutUnit containingBlockLogicalWidthInRegion = containingBlockInfo ? containingBlockInfo->logicalWidth() : containingBlockLogicalWidth;
2694 LayoutUnit marginStartInRegion = computedValues.m_margins.m_start;
2695 LayoutUnit startMarginDelta = marginStartInRegion - marginStart();
2696 LayoutUnit logicalWidthInRegion = computedValues.m_extent;
2697 LayoutUnit logicalLeftInRegion = computedValues.m_position;
2698 LayoutUnit widthDelta = logicalWidthInRegion - logicalWidth();
2699 LayoutUnit logicalLeftDelta = isOutOfFlowPositioned() ? logicalLeftInRegion - logicalLeft() : startMarginDelta;
2700 LayoutUnit logicalRightInRegion = containingBlockLogicalWidthInRegion - (logicalLeftInRegion + logicalWidthInRegion);
2701 LayoutUnit oldLogicalRight = containingBlockLogicalWidth - (logicalLeft() + logicalWidth());
2702 LayoutUnit logicalRightDelta = isOutOfFlowPositioned() ? logicalRightInRegion - oldLogicalRight : startMarginDelta;
2704 LayoutUnit logicalLeftOffset = 0;
2706 if (!isOutOfFlowPositioned() && avoidsFloats() && cb.containsFloats()) {
2707 LayoutUnit startPositionDelta = cb.computeStartPositionDeltaForChildAvoidingFloats(*this, marginStartInRegion, region);
2708 if (cb.style().isLeftToRightDirection())
2709 logicalLeftDelta += startPositionDelta;
2711 logicalRightDelta += startPositionDelta;
2714 if (cb.style().isLeftToRightDirection())
2715 logicalLeftOffset += logicalLeftDelta;
2717 logicalLeftOffset -= (widthDelta + logicalRightDelta);
2719 LayoutUnit logicalRightOffset = logicalWidth() - (logicalLeftOffset + logicalWidthInRegion);
2720 bool isShifted = (containingBlockInfo && containingBlockInfo->isShifted())
2721 || (style().isLeftToRightDirection() && logicalLeftOffset)
2722 || (!style().isLeftToRightDirection() && logicalRightOffset);
2724 // FIXME: Although it's unlikely, these boxes can go outside our bounds, and so we will need to incorporate them into overflow.
2725 if (cacheFlag == CacheRenderBoxRegionInfo)
2726 return region->setRenderBoxRegionInfo(this, logicalLeftOffset, logicalWidthInRegion, isShifted);
2727 return new RenderBoxRegionInfo(logicalLeftOffset, logicalWidthInRegion, isShifted);
2730 static bool shouldFlipBeforeAfterMargins(const RenderStyle& containingBlockStyle, const RenderStyle* childStyle)
2732 ASSERT(containingBlockStyle.isHorizontalWritingMode() != childStyle->isHorizontalWritingMode());
2733 WritingMode childWritingMode = childStyle->writingMode();
2734 bool shouldFlip = false;
2735 switch (containingBlockStyle.writingMode()) {
2736 case TopToBottomWritingMode:
2737 shouldFlip = (childWritingMode == RightToLeftWritingMode);
2739 case BottomToTopWritingMode:
2740 shouldFlip = (childWritingMode == RightToLeftWritingMode);
2742 case RightToLeftWritingMode:
2743 shouldFlip = (childWritingMode == BottomToTopWritingMode);
2745 case LeftToRightWritingMode:
2746 shouldFlip = (childWritingMode == BottomToTopWritingMode);
2750 if (!containingBlockStyle.isLeftToRightDirection())
2751 shouldFlip = !shouldFlip;
2756 void RenderBox::updateLogicalHeight()
2758 LogicalExtentComputedValues computedValues;
2759 computeLogicalHeight(logicalHeight(), logicalTop(), computedValues);
2761 setLogicalHeight(computedValues.m_extent);
2762 setLogicalTop(computedValues.m_position);
2763 setMarginBefore(computedValues.m_margins.m_before);
2764 setMarginAfter(computedValues.m_margins.m_after);
2767 void RenderBox::computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit logicalTop, LogicalExtentComputedValues& computedValues) const
2769 computedValues.m_extent = logicalHeight;
2770 computedValues.m_position = logicalTop;
2772 // Cell height is managed by the table and inline non-replaced elements do not support a height property.
2773 if (isTableCell() || (isInline() && !isReplaced()))
2777 if (isOutOfFlowPositioned())
2778 computePositionedLogicalHeight(computedValues);
2780 RenderBlock& cb = *containingBlock();
2781 bool hasPerpendicularContainingBlock = cb.isHorizontalWritingMode() != isHorizontalWritingMode();
2783 if (!hasPerpendicularContainingBlock) {
2784 bool shouldFlipBeforeAfter = cb.style().writingMode() != style().writingMode();
2785 computeBlockDirectionMargins(cb,
2786 shouldFlipBeforeAfter ? computedValues.m_margins.m_after : computedValues.m_margins.m_before,
2787 shouldFlipBeforeAfter ? computedValues.m_margins.m_before : computedValues.m_margins.m_after);
2790 // For tables, calculate margins only.
2792 if (hasPerpendicularContainingBlock) {
2793 bool shouldFlipBeforeAfter = shouldFlipBeforeAfterMargins(cb.style(), &style());
2794 computeInlineDirectionMargins(cb, containingBlockLogicalWidthForContent(), computedValues.m_extent,
2795 shouldFlipBeforeAfter ? computedValues.m_margins.m_after : computedValues.m_margins.m_before,
2796 shouldFlipBeforeAfter ? computedValues.m_margins.m_before : computedValues.m_margins.m_after);
2801 // FIXME: Account for block-flow in flexible boxes.
2802 // https://bugs.webkit.org/show_bug.cgi?id=46418
2803 bool inHorizontalBox = parent()->isDeprecatedFlexibleBox() && parent()->style().boxOrient() == HORIZONTAL;
2804 bool stretching = parent()->style().boxAlign() == BSTRETCH;
2805 bool treatAsReplaced = shouldComputeSizeAsReplaced() && (!inHorizontalBox || !stretching);
2806 bool checkMinMaxHeight = false;
2808 // The parent box is flexing us, so it has increased or decreased our height. We have to
2809 // grab our cached flexible height.
2810 // FIXME: Account for block-flow in flexible boxes.
2811 // https://bugs.webkit.org/show_bug.cgi?id=46418
2812 if (hasOverrideLogicalContentHeight() && (parent()->isFlexibleBoxIncludingDeprecated()
2813 #if ENABLE(CSS_GRID_LAYOUT)
2814 || parent()->isRenderGrid()
2817 LayoutUnit contentHeight = overrideLogicalContentHeight();
2818 #if ENABLE(CSS_GRID_LAYOUT)
2819 if (parent()->isRenderGrid() && style().logicalHeight().isAuto() && style().logicalMinHeight().isAuto() && style().overflowX() == OVISIBLE) {
2820 LayoutUnit intrinsicContentHeight = computedValues.m_extent - borderAndPaddingLogicalHeight();
2821 if (auto minContentHeight = computeContentLogicalHeight(MinSize, Length(MinContent), intrinsicContentHeight))
2822 contentHeight = std::max(contentHeight, constrainContentBoxLogicalHeightByMinMax(minContentHeight.value(), intrinsicContentHeight));
2825 h = Length(contentHeight, Fixed);
2826 } else if (treatAsReplaced)
2827 h = Length(computeReplacedLogicalHeight(), Fixed);
2829 h = style().logicalHeight();
2830 checkMinMaxHeight = true;
2833 // Block children of horizontal flexible boxes fill the height of the box.
2834 // FIXME: Account for block-flow in flexible boxes.
2835 // https://bugs.webkit.org/show_bug.cgi?id=46418
2836 if (h.isAuto() && is<RenderDeprecatedFlexibleBox>(*parent()) && parent()->style().boxOrient() == HORIZONTAL
2837 && downcast<RenderDeprecatedFlexibleBox>(*parent()).isStretchingChildren()) {
2838 h = Length(parentBox()->contentLogicalHeight() - marginBefore() - marginAfter() - borderAndPaddingLogicalHeight(), Fixed);
2839 checkMinMaxHeight = false;
2842 LayoutUnit heightResult;
2843 if (checkMinMaxHeight) {
2844 LayoutUnit intrinsicHeight = computedValues.m_extent - borderAndPaddingLogicalHeight();
2845 heightResult = computeLogicalHeightUsing(MainOrPreferredSize, style().logicalHeight(), intrinsicHeight).valueOr(computedValues.m_extent);
2846 heightResult = constrainLogicalHeightByMinMax(heightResult, intrinsicHeight);
2848 // The only times we don't check min/max height are when a fixed length has
2849 // been given as an override. Just use that. The value has already been adjusted
2851 ASSERT(h.isFixed());
2852 heightResult = h.value() + borderAndPaddingLogicalHeight();
2855 computedValues.m_extent = heightResult;
2857 if (hasPerpendicularContainingBlock) {
2858 bool shouldFlipBeforeAfter = shouldFlipBeforeAfterMargins(cb.style(), &style());
2859 computeInlineDirectionMargins(cb, containingBlockLogicalWidthForContent(), heightResult,
2860 shouldFlipBeforeAfter ? computedValues.m_margins.m_after : computedValues.m_margins.m_before,
2861 shouldFlipBeforeAfter ? computedValues.m_margins.m_before : computedValues.m_margins.m_after);
2865 // WinIE quirk: The <html> block always fills the entire canvas in quirks mode. The <body> always fills the
2866 // <html> block in quirks mode. Only apply this quirk if the block is normal flow and no height
2867 // is specified. When we're printing, we also need this quirk if the body or root has a percentage
2868 // height since we don't set a height in RenderView when we're printing. So without this quirk, the
2869 // height has nothing to be a percentage of, and it ends up being 0. That is bad.
2870 bool paginatedContentNeedsBaseHeight = document().printing() && h.isPercentOrCalculated()
2871 && (isDocumentElementRenderer() || (isBody() && document().documentElement()->renderer()->style().logicalHeight().isPercentOrCalculated())) && !isInline();
2872 if (stretchesToViewport() || paginatedContentNeedsBaseHeight) {
2873 LayoutUnit margins = collapsedMarginBefore() + collapsedMarginAfter();
2874 LayoutUnit visibleHeight = view().pageOrViewLogicalHeight();
2875 if (isDocumentElementRenderer())
2876 computedValues.m_extent = std::max(computedValues.m_extent, visibleHeight - margins);
2878 LayoutUnit marginsBordersPadding = margins + parentBox()->marginBefore() + parentBox()->marginAfter() + parentBox()->borderAndPaddingLogicalHeight();
2879 computedValues.m_extent = std::max(computedValues.m_extent, visibleHeight - marginsBordersPadding);
2884 Optional<LayoutUnit> RenderBox::computeLogicalHeightUsing(SizeType heightType, const Length& height, Optional<LayoutUnit> intrinsicContentHeight) const
2886 if (Optional<LayoutUnit> logicalHeight = computeContentAndScrollbarLogicalHeightUsing(heightType, height, intrinsicContentHeight))
2887 return adjustBorderBoxLogicalHeightForBoxSizing(logicalHeight.value());
2891 Optional<LayoutUnit> RenderBox::computeContentLogicalHeight(SizeType heightType, const Length& height, Optional<LayoutUnit> intrinsicContentHeight) const
2893 if (Optional<LayoutUnit> heightIncludingScrollbar = computeContentAndScrollbarLogicalHeightUsing(heightType, height, intrinsicContentHeight))
2894 return std::max<LayoutUnit>(0, adjustContentBoxLogicalHeightForBoxSizing(heightIncludingScrollbar) - scrollbarLogicalHeight());
2898 Optional<LayoutUnit> RenderBox::computeIntrinsicLogicalContentHeightUsing(Length logicalHeightLength, Optional<LayoutUnit> intrinsicContentHeight, LayoutUnit borderAndPadding) const
2900 // FIXME: The CSS sizing spec is considering changing what min-content/max-content should resolve to.
2901 // If that happens, this code will have to change.
2902 if (logicalHeightLength.isMinContent() || logicalHeightLength.isMaxContent() || logicalHeightLength.isFitContent()) {
2903 if (!intrinsicContentHeight)
2904 return intrinsicContentHeight;
2905 if (style().boxSizing() == BORDER_BOX)
2906 return intrinsicContentHeight.value() + borderAndPaddingLogicalHeight();
2907 return intrinsicContentHeight;
2909 if (logicalHeightLength.isFillAvailable())
2910 return containingBlock()->availableLogicalHeight(ExcludeMarginBorderPadding) - borderAndPadding;
2911 ASSERT_NOT_REACHED();
2912 return LayoutUnit(0);
2915 Optional<LayoutUnit> RenderBox::computeContentAndScrollbarLogicalHeightUsing(SizeType heightType, const Length& height, Optional<LayoutUnit> intrinsicContentHeight) const
2917 if (height.isAuto())
2918 return heightType == MinSize ? Optional<LayoutUnit>(0) : Nullopt;
2919 // FIXME: The CSS sizing spec is considering changing what min-content/max-content should resolve to.
2920 // If that happens, this code will have to change.
2921 if (height.isIntrinsic())
2922 return computeIntrinsicLogicalContentHeightUsing(height, intrinsicContentHeight, borderAndPaddingLogicalHeight());
2923 if (height.isFixed())
2924 return LayoutUnit(height.value());
2925 if (height.isPercentOrCalculated())
2926 return computePercentageLogicalHeight(height);
2930 bool RenderBox::skipContainingBlockForPercentHeightCalculation(const RenderBox& containingBlock, bool isPerpendicularWritingMode) const
2932 // Flow threads for multicol or paged overflow should be skipped. They are invisible to the DOM,
2933 // and percent heights of children should be resolved against the multicol or paged container.
2934 if (containingBlock.isInFlowRenderFlowThread() && !isPerpendicularWritingMode)
2937 // For quirks mode and anonymous blocks, we skip auto-height containingBlocks when computing percentages.
2938 // For standards mode, we treat the percentage as auto if it has an auto-height containing block.
2939 if (!document().inQuirksMode() && !containingBlock.isAnonymousBlock())
2941 return !containingBlock.isTableCell() && !containingBlock.isOutOfFlowPositioned() && containingBlock.style().logicalHeight().isAuto() && isHorizontalWritingMode() == containingBlock.isHorizontalWritingMode();
2944 static bool tableCellShouldHaveZeroInitialSize(const RenderBlock& block, bool scrollsOverflowY)
2946 // Normally we would let the cell size intrinsically, but scrolling overflow has to be
2947 // treated differently, since WinIE lets scrolled overflow regions shrink as needed.
2948 // While we can't get all cases right, we can at least detect when the cell has a specified
2949 // height or when the table has a specified height. In these cases we want to initially have
2950 // no size and allow the flexing of the table or the cell to its specified height to cause us
2951 // to grow to fill the space. This could end up being wrong in some cases, but it is
2952 // preferable to the alternative (sizing intrinsically and making the row end up too big).
2953 const RenderTableCell& cell = downcast<RenderTableCell>(block);
2954 return scrollsOverflowY && (!cell.style().logicalHeight().isAuto() || !cell.table()->style().logicalHeight().isAuto());
2957 Optional<LayoutUnit> RenderBox::computePercentageLogicalHeight(const Length& height) const
2959 Optional<LayoutUnit> availableHeight;
2961 bool skippedAutoHeightContainingBlock = false;
2962 RenderBlock* cb = containingBlock();
2963 const RenderBox* containingBlockChild = this;
2964 LayoutUnit rootMarginBorderPaddingHeight = 0;
2965 bool isHorizontal = isHorizontalWritingMode();
2966 while (cb && !is<RenderView>(*cb) && skipContainingBlockForPercentHeightCalculation(*cb, isHorizontal != cb->isHorizontalWritingMode())) {
2967 if (cb->isBody() || cb->isDocumentElementRenderer())
2968 rootMarginBorderPaddingHeight += cb->marginBefore() + cb->marginAfter() + cb->borderAndPaddingLogicalHeight();
2969 skippedAutoHeightContainingBlock = true;
2970 containingBlockChild = cb;
2971 cb = cb->containingBlock();
2972 cb->addPercentHeightDescendant(const_cast<RenderBox&>(*this));
2975 const RenderStyle& cbstyle = cb->style();
2977 // A positioned element that specified both top/bottom or that specifies height should be treated as though it has a height
2978 // explicitly specified that can be used for any percentage computations.
2979 bool isOutOfFlowPositionedWithSpecifiedHeight = cb->isOutOfFlowPositioned() && (!cbstyle.logicalHeight().isAuto() || (!cbstyle.logicalTop().isAuto() && !cbstyle.logicalBottom().isAuto()));
2981 bool includeBorderPadding = isTable();
2983 if (isHorizontal != cb->isHorizontalWritingMode())
2984 availableHeight = containingBlockChild->containingBlockLogicalWidthForContent();
2985 #if ENABLE(CSS_GRID_LAYOUT)
2986 else if (hasOverrideContainingBlockLogicalHeight())
2987 availableHeight = overrideContainingBlockContentLogicalHeight();
2989 else if (is<RenderTableCell>(*cb)) {
2990 if (!skippedAutoHeightContainingBlock) {
2991 // Table cells violate what the CSS spec says to do with heights. Basically we
2992 // don't care if the cell specified a height or not. We just always make ourselves
2993 // be a percentage of the cell's current content height.
2994 if (!cb->hasOverrideLogicalContentHeight())
2995 return tableCellShouldHaveZeroInitialSize(*cb, scrollsOverflowY()) ? Optional<LayoutUnit>() : Nullopt;
2997 availableHeight = cb->overrideLogicalContentHeight();
2998 includeBorderPadding = true;
3000 } else if (cbstyle.logicalHeight().isFixed()) {
3001 LayoutUnit contentBoxHeight = cb->adjustContentBoxLogicalHeightForBoxSizing(LayoutUnit(cbstyle.logicalHeight().value()));
3002 availableHeight = std::max<LayoutUnit>(0, cb->constrainContentBoxLogicalHeightByMinMax(contentBoxHeight - cb->scrollbarLogicalHeight(), Nullopt));
3003 } else if (cbstyle.logicalHeight().isPercentOrCalculated() && !isOutOfFlowPositionedWithSpecifiedHeight) {
3004 // We need to recur and compute the percentage height for our containing block.
3005 if (Optional<LayoutUnit> heightWithScrollbar = cb->computePercentageLogicalHeight(cbstyle.logicalHeight())) {
3006 LayoutUnit contentBoxHeightWithScrollbar = cb->adjustContentBoxLogicalHeightForBoxSizing(heightWithScrollbar);
3007 // We need to adjust for min/max height because this method does not
3008 // handle the min/max of the current block, its caller does. So the
3009 // return value from the recursive call will not have been adjusted
3011 LayoutUnit contentBoxHeight = cb->constrainContentBoxLogicalHeightByMinMax(contentBoxHeightWithScrollbar - cb->scrollbarLogicalHeight(), Nullopt);
3012 availableHeight = std::max<LayoutUnit>(0, contentBoxHeight);
3014 } else if (isOutOfFlowPositionedWithSpecifiedHeight) {
3015 // Don't allow this to affect the block' height() member variable, since this
3016 // can get called while the block is still laying out its kids.
3017 LogicalExtentComputedValues computedValues;
3018 cb->computeLogicalHeight(cb->logicalHeight(), 0, computedValues);
3019 availableHeight = computedValues.m_extent - cb->borderAndPaddingLogicalHeight() - cb->scrollbarLogicalHeight();
3020 } else if (cb->isRenderView())
3021 availableHeight = view().pageOrViewLogicalHeight();
3023 if (!availableHeight)
3024 return availableHeight;
3026 LayoutUnit result = valueForLength(height, availableHeight.value() - rootMarginBorderPaddingHeight);
3027 if (includeBorderPadding) {
3028 // FIXME: Table cells should default to box-sizing: border-box so we can avoid this hack.
3029 // It is necessary to use the border-box to match WinIE's broken
3030 // box model. This is essential for sizing inside
3031 // table cells using percentage heights.
3032 result -= borderAndPaddingLogicalHeight();
3033 return std::max<LayoutUnit>(0, result);
3038 LayoutUnit RenderBox::computeReplacedLogicalWidth(ShouldComputePreferred shouldComputePreferred) const
3040 return computeReplacedLogicalWidthRespectingMinMaxWidth(computeReplacedLogicalWidthUsing(MainOrPreferredSize, style().logicalWidth()), shouldComputePreferred);
3043 LayoutUnit RenderBox::computeReplacedLogicalWidthRespectingMinMaxWidth(LayoutUnit logicalWidth, ShouldComputePreferred shouldComputePreferred) const
3045 auto& logicalMinWidth = style().logicalMinWidth();
3046 auto& logicalMaxWidth = style().logicalMaxWidth();
3047 bool useLogicalWidthForMinWidth = (shouldComputePreferred == ComputePreferred && logicalMinWidth.isPercentOrCalculated()) || logicalMinWidth.isUndefined();
3048 bool useLogicalWidthForMaxWidth = (shouldComputePreferred == ComputePreferred && logicalMaxWidth.isPercentOrCalculated()) || logicalMaxWidth.isUndefined();
3049 auto minLogicalWidth = useLogicalWidthForMinWidth ? logicalWidth : computeReplacedLogicalWidthUsing(MinSize, logicalMinWidth);
3050 auto maxLogicalWidth = useLogicalWidthForMaxWidth ? logicalWidth : computeReplacedLogicalWidthUsing(MaxSize, logicalMaxWidth);
3051 return std::max(minLogicalWidth, std::min(logicalWidth, maxLogicalWidth));
3054 LayoutUnit RenderBox::computeReplacedLogicalWidthUsing(SizeType widthType, Length logicalWidth) const
3056 ASSERT(widthType == MinSize || widthType == MainOrPreferredSize || !logicalWidth.isAuto());
3057 if (widthType == MinSize && logicalWidth.isAuto())
3058 return adjustContentBoxLogicalWidthForBoxSizing(0);
3060 switch (logicalWidth.type()) {
3062 return adjustContentBoxLogicalWidthForBoxSizing(logicalWidth.value());
3065 // MinContent/MaxContent don't need the availableLogicalWidth argument.
3066 LayoutUnit availableLogicalWidth = 0;
3067 return computeIntrinsicLogicalWidthUsing(logicalWidth, availableLogicalWidth, borderAndPaddingLogicalWidth()) - borderAndPaddingLogicalWidth();
3073 // FIXME: containingBlockLogicalWidthForContent() is wrong if the replaced element's block-flow is perpendicular to the
3074 // containing block's block-flow.
3075 // https://bugs.webkit.org/show_bug.cgi?id=46496
3076 const LayoutUnit cw = isOutOfFlowPositioned() ? containingBlockLogicalWidthForPositioned(downcast<RenderBoxModelObject>(*container())) : containingBlockLogicalWidthForContent();
3077 Length containerLogicalWidth = containingBlock()->style().logicalWidth();
3078 // FIXME: Handle cases when containing block width is calculated or viewport percent.
3079 // https://bugs.webkit.org/show_bug.cgi?id=91071
3080 if (logicalWidth.isIntrinsic())
3081 return computeIntrinsicLogicalWidthUsing(logicalWidth, cw, borderAndPaddingLogicalWidth()) - borderAndPaddingLogicalWidth();
3082 if (cw > 0 || (!cw && (containerLogicalWidth.isFixed() || containerLogicalWidth.isPercentOrCalculated())))
3083 return adjustContentBoxLogicalWidthForBoxSizing(minimumValueForLength(logicalWidth, cw));
3091 return intrinsicLogicalWidth();
3094 ASSERT_NOT_REACHED();
3098 LayoutUnit RenderBox::computeReplacedLogicalHeight() const
3100 return computeReplacedLogicalHeightRespectingMinMaxHeight(computeReplacedLogicalHeightUsing(MainOrPreferredSize, style().logicalHeight()));
3103 LayoutUnit RenderBox::computeReplacedLogicalHeightRespectingMinMaxHeight(LayoutUnit logicalHeight) const
3105 LayoutUnit minLogicalHeight = computeReplacedLogicalHeightUsing(MinSize, style().logicalMinHeight());
3106 LayoutUnit maxLogicalHeight = style().logicalMaxHeight().isUndefined() ? logicalHeight : computeReplacedLogicalHeightUsing(MaxSize, style().logicalMaxHeight());
3107 return std::max(minLogicalHeight, std::min(logicalHeight, maxLogicalHeight));
3110 LayoutUnit RenderBox::computeReplacedLogicalHeightUsing(SizeType heightType, Length logicalHeight) const
3112 ASSERT(heightType == MinSize || heightType == MainOrPreferredSize || !logicalHeight.isAuto());
3113 if (heightType == MinSize && logicalHeight.isAuto())
3114 return adjustContentBoxLogicalHeightForBoxSizing(Optional<LayoutUnit>(0));
3116 switch (logicalHeight.type()) {
3118 return adjustContentBoxLogicalHeightForBoxSizing(LayoutUnit(logicalHeight.value()));
3122 auto cb = isOutOfFlowPositioned() ? container() : containingBlock();
3123 while (cb && cb->isAnonymous() && !is<RenderView>(*cb)) {
3124 cb = cb->containingBlock();
3125 downcast<RenderBlock>(*cb).addPercentHeightDescendant(const_cast<RenderBox&>(*this));
3128 // FIXME: This calculation is not patched for block-flow yet.
3129 // https://bugs.webkit.org/show_bug.cgi?id=46500
3130 if (cb->isOutOfFlowPositioned() && cb->style().height().isAuto() && !(cb->style().top().isAuto() || cb->style().bottom().isAuto())) {
3131 ASSERT_WITH_SECURITY_IMPLICATION(cb->isRenderBlock());
3132 RenderBlock& block = downcast<RenderBlock>(*cb);
3133 LogicalExtentComputedValues computedValues;
3134 block.computeLogicalHeight(block.logicalHeight(), 0, computedValues);
3135 LayoutUnit newContentHeight = computedValues.m_extent - block.borderAndPaddingLogicalHeight() - block.scrollbarLogicalHeight();
3136 LayoutUnit newHeight = block.adjustContentBoxLogicalHeightForBoxSizing(newContentHeight);
3137 return adjustContentBoxLogicalHeightForBoxSizing(valueForLength(logicalHeight, newHeight));
3140 // FIXME: availableLogicalHeight() is wrong if the replaced element's block-flow is perpendicular to the
3141 // containing block's block-flow.
3142 // https://bugs.webkit.org/show_bug.cgi?id=46496
3143 LayoutUnit availableHeight;
3144 if (isOutOfFlowPositioned())
3145 availableHeight = containingBlockLogicalHeightForPositioned(downcast<RenderBoxModelObject>(*cb));
3147 availableHeight = containingBlockLogicalHeightForContent(IncludeMarginBorderPadding);
3148 // It is necessary to use the border-box to match WinIE's broken
3149 // box model. This is essential for sizing inside
3150 // table cells using percentage heights.
3151 // FIXME: This needs to be made block-flow-aware. If the cell and image are perpendicular block-flows, this isn't right.
3152 // https://bugs.webkit.org/show_bug.cgi?id=46997
3153 while (cb && !is<RenderView>(*cb) && (cb->style().logicalHeight().isAuto() || cb->style().logicalHeight().isPercentOrCalculated())) {
3154 if (cb->isTableCell()) {
3155 // Don't let table cells squeeze percent-height replaced elements
3156 // <http://bugs.webkit.org/show_bug.cgi?id=15359>
3157 availableHeight = std::max(availableHeight, intrinsicLogicalHeight());
3158 return valueForLength(logicalHeight, availableHeight - borderAndPaddingLogicalHeight());
3160 downcast<RenderBlock>(*cb).addPercentHeightDescendant(const_cast<RenderBox&>(*this));
3161 cb = cb->containingBlock();
3164 return adjustContentBoxLogicalHeightForBoxSizing(valueForLength(logicalHeight, availableHeight));
3170 return adjustContentBoxLogicalHeightForBoxSizing(computeIntrinsicLogicalContentHeightUsing(logicalHeight, intrinsicLogicalHeight(), borderAndPaddingLogicalHeight()));
3172 return intrinsicLogicalHeight();
3176 LayoutUnit RenderBox::availableLogicalHeight(AvailableLogicalHeightType heightType) const
3178 return constrainLogicalHeightByMinMax(availableLogicalHeightUsing(style().logicalHeight(), heightType), Nullopt);
3181 LayoutUnit RenderBox::availableLogicalHeightUsing(const Length& h, AvailableLogicalHeightType heightType) const
3183 // We need to stop here, since we don't want to increase the height of the table
3184 // artificially. We're going to rely on this cell getting expanded to some new
3185 // height, and then when we lay out again we'll use the calculation below.
3186 if (isTableCell() && (h.isAuto() || h.isPercentOrCalculated())) {
3187 if (hasOverrideLogicalContentHeight())
3188 return overrideLogicalContentHeight();
3189 return logicalHeight() - borderAndPaddingLogicalHeight();
3192 if (h.isPercentOrCalculated() && isOutOfFlowPositioned() && !isRenderFlowThread()) {
3193 // FIXME: This is wrong if the containingBlock has a perpendicular writing mode.
3194 LayoutUnit availableHeight = containingBlockLogicalHeightForPositioned(*containingBlock());
3195 return adjustContentBoxLogicalHeightForBoxSizing(valueForLength(h, availableHeight));
3198 if (Optional<LayoutUnit> heightIncludingScrollbar = computeContentAndScrollbarLogicalHeightUsing(MainOrPreferredSize, h, Nullopt))
3199 return std::max<LayoutUnit>(0, adjustContentBoxLogicalHeightForBoxSizing(heightIncludingScrollbar) - scrollbarLogicalHeight());
3201 // FIXME: Check logicalTop/logicalBottom here to correctly handle vertical writing-mode.
3202 // https://bugs.webkit.org/show_bug.cgi?id=46500
3203 if (is<RenderBlock>(*this) && isOutOfFlowPositioned() && style().height().isAuto() && !(style().top().isAuto() || style().bottom().isAuto())) {
3204 RenderBlock& block = const_cast<RenderBlock&>(downcast<RenderBlock>(*this));
3205 LogicalExtentComputedValues computedValues;
3206 block.computeLogicalHeight(block.logicalHeight(), 0, computedValues);
3207 LayoutUnit newContentHeight = computedValues.m_extent - block.borderAndPaddingLogicalHeight() - block.scrollbarLogicalHeight();
3208 return adjustContentBoxLogicalHeightForBoxSizing(newContentHeight);
3211 // FIXME: This is wrong if the containingBlock has a perpendicular writing mode.
3212 LayoutUnit availableHeight = containingBlockLogicalHeightForContent(heightType);
3213 if (heightType == ExcludeMarginBorderPadding) {
3214 // FIXME: Margin collapsing hasn't happened yet, so this incorrectly removes collapsed margins.
3215 availableHeight -= marginBefore() + marginAfter() + borderAndPaddingLogicalHeight();
3217 return availableHeight;
3220 void RenderBox::computeBlockDirectionMargins(const RenderBlock& containingBlock, LayoutUnit& marginBefore, LayoutUnit& marginAfter) const
3222 if (isTableCell()) {
3223 // FIXME: Not right if we allow cells to have different directionality than the table. If we do allow this, though,
3224 // we may just do it with an extra anonymous block inside the cell.
3230 // Margins are calculated with respect to the logical width of
3231 // the containing block (8.3)
3232 LayoutUnit cw = containingBlockLogicalWidthForContent();
3233 const RenderStyle& containingBlockStyle = containingBlock.style();
3234 marginBefore = minimumValueForLength(style().marginBeforeUsing(&containingBlockStyle), cw);
3235 marginAfter = minimumValueForLength(style().marginAfterUsing(&containingBlockStyle), cw);
3238 void RenderBox::computeAndSetBlockDirectionMargins(const RenderBlock& containingBlock)
3240 LayoutUnit marginBefore;
3241 LayoutUnit marginAfter;
3242 computeBlockDirectionMargins(containingBlock, marginBefore, marginAfter);
3243 containingBlock.setMarginBeforeForChild(*this, marginBefore);
3244 containingBlock.setMarginAfterForChild(*this, marginAfter);
3247 LayoutUnit RenderBox::containingBlockLogicalWidthForPositioned(const RenderBoxModelObject& containingBlock, RenderRegion* region, bool checkForPerpendicularWritingMode) const
3249 if (checkForPerpendicularWritingMode && containingBlock.isHorizontalWritingMode() != isHorizontalWritingMode())
3250 return containingBlockLogicalHeightForPositioned(containingBlock, false);
3252 #if ENABLE(CSS_GRID_LAYOUT)
3253 if (hasOverrideContainingBlockLogicalWidth()) {
3254 if (auto overrideLogicalWidth = overrideContainingBlockContentLogicalWidth())
3255 return overrideLogicalWidth.value();
3259 if (is<RenderBox>(containingBlock)) {
3260 bool isFixedPosition = style().position() == FixedPosition;
3262 RenderFlowThread* flowThread = flowThreadContainingBlock();
3264 if (isFixedPosition && is<RenderView>(containingBlock))
3265 return downcast<RenderView>(containingBlock).clientLogicalWidthForFixedPosition();
3267 return downcast<RenderBox>(containingBlock).clientLogicalWidth();
3270 if (isFixedPosition && is<RenderNamedFlowThread>(containingBlock))
3271 return containingBlock.view().clientLogicalWidth();
3273 if (!is<RenderBlock>(containingBlock))
3274 return downcast<RenderBox>(containingBlock).clientLogicalWidth();
3276 const RenderBlock& cb = downcast<RenderBlock>(containingBlock);
3277 RenderBoxRegionInfo* boxInfo = nullptr;
3279 if (is<RenderFlowThread>(containingBlock) && !checkForPerpendicularWritingMode)
3280 return downcast<RenderFlowThread>(containingBlock).contentLogicalWidthOfFirstRegion();
3281 if (isWritingModeRoot()) {
3282 LayoutUnit cbPageOffset = cb.offsetFromLogicalTopOfFirstPage();
3283 RenderRegion* cbRegion = cb.regionAtBlockOffset(cbPageOffset);
3285 boxInfo = cb.renderBoxRegionInfo(cbRegion);
3287 } else if (flowThread->isHorizontalWritingMode() == containingBlock.isHorizontalWritingMode()) {
3288 RenderRegion* containingBlockRegion = cb.clampToStartAndEndRegions(region);
3289 boxInfo = cb.renderBoxRegionInfo(containingBlockRegion);
3291 return (boxInfo) ? std::max<LayoutUnit>(0, cb.clientLogicalWidth() - (cb.logicalWidth() - boxInfo->logicalWidth())) : cb.clientLogicalWidth();
3294 ASSERT(containingBlock.isInFlowPositioned());
3296 const auto& flow = downcast<RenderInline>(containingBlock);
3297 InlineFlowBox* first = flow.firstLineBox();
3298 InlineFlowBox* last = flow.lastLineBox();
3300 // If the containing block is empty, return a width of 0.
3301 if (!first || !last)
3304 LayoutUnit fromLeft;
3305 LayoutUnit fromRight;
3306 if (containingBlock.style().isLeftToRightDirection()) {
3307 fromLeft = first->logicalLeft() + first->borderLogicalLeft();
3308 fromRight = last->logicalLeft() + last->logicalWidth() - last->borderLogicalRight();
3310 fromRight = first->logicalLeft() + first->logicalWidth() - first->borderLogicalRight();
3311 fromLeft = last->logicalLeft() + last->borderLogicalLeft();
3314 return std::max<LayoutUnit>(0, fromRight - fromLeft);
3317 LayoutUnit RenderBox::containingBlockLogicalHeightForPositioned(const RenderBoxModelObject& containingBlock, bool checkForPerpendicularWritingMode) const
3319 if (checkForPerpendicularWritingMode && containingBlock.isHorizontalWritingMode() != isHorizontalWritingMode())
3320 return containingBlockLogicalWidthForPositioned(containingBlock, nullptr, false);
3322 #if ENABLE(CSS_GRID_LAYOUT)
3323 if (hasOverrideContainingBlockLogicalHeight()) {
3324 if (auto overrideLogicalHeight = overrideContainingBlockContentLogicalHeight())
3325 return overrideLogicalHeight.value();
3329 if (containingBlock.isBox()) {
3330 bool isFixedPosition = style().position() == FixedPosition;
3332 if (isFixedPosition && is<RenderView>(containingBlock))
3333 return downcast<RenderView>(containingBlock).clientLogicalHeightForFixedPosition();
3335 const RenderBlock& cb = is<RenderBlock>(containingBlock) ? downcast<RenderBlock>(containingBlock) : *containingBlock.containingBlock();
3336 LayoutUnit result = cb.clientLogicalHeight();
3337 RenderFlowThread* flowThread = flowThreadContainingBlock();
3338 if (flowThread && is<RenderFlowThread>(containingBlock) && flowThread->isHorizontalWritingMode() == containingBlock.isHorizontalWritingMode()) {
3339 if (is<RenderNamedFlowThread>(containingBlock) && isFixedPosition)
3340 return containingBlock.view().clientLogicalHeight();
3341 return downcast<RenderFlowThread>(containingBlock).contentLogicalHeightOfFirstRegion();
3346 ASSERT(containingBlock.isInFlowPositioned());
3348 const auto& flow = downcast<RenderInline>(containingBlock);
3349 InlineFlowBox* first = flow.firstLineBox();
3350 InlineFlowBox* last = flow.lastLineBox();
3352 // If the containing block is empty, return a height of 0.
3353 if (!first || !last)
3356 LayoutUnit heightResult;
3357 LayoutRect boundingBox = flow.linesBoundingBox();
3358 if (containingBlock.isHorizontalWritingMode())
3359 heightResult = boundingBox.height();
3361 heightResult = boundingBox.width();
3362 heightResult -= (containingBlock.borderBefore() + containingBlock.borderAfter());
3363 return heightResult;
3366 static void computeInlineStaticDistance(Length& logicalLeft, Length& logicalRight, const RenderBox* child, const RenderBoxModelObject& containerBlock, LayoutUnit containerLogicalWidth, RenderRegion* region)
3368 if (!logicalLeft.isAuto() || !logicalRight.isAuto())
3371 // FIXME: The static distance computation has not been patched for mixed writing modes yet.
3372 if (child->parent()->style().direction() == LTR) {
3373 LayoutUnit staticPosition = child->layer()->staticInlinePosition() - containerBlock.borderLogicalLeft();
3374 for (auto* current = child->parent(); current && current != &containerBlock; current = current->container()) {
3375 if (!is<RenderBox>(*current))
3377 const auto& renderBox = downcast<RenderBox>(*current);
3378 staticPosition += renderBox.logicalLeft();
3379 if (renderBox.isInFlowPositioned())
3380 staticPosition += renderBox.isHorizontalWritingMode() ? renderBox.offsetForInFlowPosition().width() : renderBox.offsetForInFlowPosition().height();
3381 if (region && is<RenderBlock>(*current)) {
3382 const RenderBlock& currentBlock = downcast<RenderBlock>(*current);
3383 region = currentBlock.clampToStartAndEndRegions(region);
3384 RenderBoxRegionInfo* boxInfo = currentBlock.renderBoxRegionInfo(region);
3386 staticPosition += boxInfo->logicalLeft();
3389 logicalLeft.setValue(Fixed, staticPosition);
3391 LayoutUnit staticPosition = child->layer()->staticInlinePosition() + containerLogicalWidth + containerBlock.borderLogicalLeft();
3392 auto& enclosingBox = child->parent()->enclosingBox();
3393 if (&enclosingBox != &containerBlock && containerBlock.isDescendantOf(&enclosingBox)) {
3394 logicalRight.setValue(Fixed, staticPosition);
3398 staticPosition -= enclosingBox.logicalWidth();
3399 for (const RenderElement* current = &enclosingBox; current; current = current->container()) {
3400 if (!is<RenderBox>(*current))
3403 if (current != &containerBlock) {
3404 auto& renderBox = downcast<RenderBox>(*current);
3405 staticPosition -= renderBox.logicalLeft();
3406 if (renderBox.isInFlowPositioned())
3407 staticPosition -= renderBox.isHorizontalWritingMode() ? renderBox.offsetForInFlowPosition().width() : renderBox.offsetForInFlowPosition().height();
3409 if (region && is<RenderBlock>(*current)) {
3410 auto& currentBlock = downcast<RenderBlock>(*current);
3411 region = currentBlock.clampToStartAndEndRegions(region);
3412 RenderBoxRegionInfo* boxInfo = currentBlock.renderBoxRegionInfo(region);
3414 if (current != &containerBlock)
3415 staticPosition -= currentBlock.logicalWidth() - (boxInfo->logicalLeft() + boxInfo->logicalWidth());
3416 if (current == &enclosingBox)
3417 staticPosition += enclosingBox.logicalWidth() - boxInfo->logicalWidth();
3420 if (current == &containerBlock)
3423 logicalRight.setValue(Fixed, staticPosition);
3427 void RenderBox::computePositionedLogicalWidth(LogicalExtentComputedValues& computedValues, RenderRegion* region) const
3430 // FIXME: Positioned replaced elements inside a flow thread are not working properly
3431 // with variable width regions (see https://bugs.webkit.org/show_bug.cgi?id=69896 ).
3432 computePositionedLogicalWidthReplaced(computedValues);
3437 // FIXME 1: Should we still deal with these the cases of 'left' or 'right' having
3438 // the type 'static' in determining whether to calculate the static distance?
3439 // NOTE: 'static' is not a legal value for 'left' or 'right' as of CSS 2.1.
3441 // FIXME 2: Can perhaps optimize out cases when max-width/min-width are greater
3442 // than or less than the computed width(). Be careful of box-sizing and
3443 // percentage issues.
3445 // The following is based off of the W3C Working Draft from April 11, 2006 of
3446 // CSS 2.1: Section 10.3.7 "Absolutely positioned, non-replaced elements"
3447 // <http://www.w3.org/TR/CSS21/visudet.html#abs-non-replaced-width>
3448 // (block-style-comments in this function and in computePositionedLogicalWidthUsing()
3449 // correspond to text from the spec)
3452 // We don't use containingBlock(), since we may be positioned by an enclosing
3453 // relative positioned inline.
3454 const RenderBoxModelObject& containerBlock = downcast<RenderBoxModelObject>(*container());
3456 const LayoutUnit containerLogicalWidth = containingBlockLogicalWidthForPositioned(containerBlock, region);
3458 // Use the container block's direction except when calculating the static distance
3459 // This conforms with the reference results for abspos-replaced-width-margin-000.htm
3460 // of the CSS 2.1 test suite
3461 TextDirection containerDirection = containerBlock.style().direction();
3463 bool isHorizontal = isHorizontalWritingMode();
3464 const LayoutUnit bordersPlusPadding = borderAndPaddingLogicalWidth();
3465 const Length marginLogicalLeft = isHorizontal ? style().marginLeft() : style().marginTop();
3466 const Length marginLogicalRight = isHorizontal ? style().marginRight() : style().marginBottom();
3468 Length logicalLeftLength = style().logicalLeft();
3469 Length logicalRightLength = style().logicalRight();
3471 /*---------------------------------------------------------------------------*\
3472 * For the purposes of this section and the next, the term "static position"
3473 * (of an element) refers, roughly, to the position an element would have had
3474 * in the normal flow. More precisely:
3476 * * The static position for 'left' is the distance from the left edge of the
3477 * containing block to the left margin edge of a hypothetical box that would
3478 * have been the first box of the element if its 'position' property had
3479 * been 'static' and 'float' had been 'none'. The value is negative if the
3480 * hypothetical box is to the left of the containing block.
3481 * * The static position for 'right' is the distance from the right edge of the
3482 * containing block to the right margin edge of the same hypothetical box as
3483 * above. The value is positive if the hypothetical box is to the left of the
3484 * containing block's edge.
3486 * But rather than actually calculating the dimensions of that hypothetical box,
3487 * user agents are free to make a guess at its probable position.
3489 * For the purposes of calculating the static position, the containing block of
3490 * fixed positioned elements is the initial containing block instead of the
3491 * viewport, and all scrollable boxes should be assumed to be scrolled to their
3493 \*---------------------------------------------------------------------------*/
3496 // Calculate the static distance if needed.
3497 computeInlineStaticDistance(logicalLeftLength, logicalRightLength, this, containerBlock, containerLogicalWidth, region);
3499 // Calculate constraint equation values for 'width' case.
3500 computePositionedLogicalWidthUsing(MainOrPreferredSize, style().logicalWidth(), containerBlock, containerDirection,
3501 containerLogicalWidth, bordersPlusPadding,
3502 logicalLeftLength, logicalRightLength, marginLogicalLeft, marginLogicalRight,
3505 // Calculate constraint equation values for 'max-width' case.
3506 if (!style().logicalMaxWidth().isUndefined()) {
3507 LogicalExtentComputedValues maxValues;
3509 computePositionedLogicalWidthUsing(MaxSize, style().logicalMaxWidth(), containerBlock, containerDirection,
3510 containerLogicalWidth, bordersPlusPadding,
3511 logicalLeftLength, logicalRightLength, marginLogicalLeft, marginLogicalRight,
3514 if (computedValues.m_extent > maxValues.m_extent) {
3515 computedValues.m_extent = maxValues.m_extent;
3516 computedValues.m_position = maxValues.m_position;
3517 computedValues.m_margins.m_start = maxValues.m_margins.m_start;
3518 computedValues.m_margins.m_end = maxValues.m_margins.m_end;
3522 // Calculate constraint equation values for 'min-width' case.
3523 if (!style().logicalMinWidth().isZero() || style().logicalMinWidth().isIntrinsic()) {
3524 LogicalExtentComputedValues minValues;
3526 computePositionedLogicalWidthUsing(MinSize, style().logicalMinWidth(), containerBlock, containerDirection,
3527 containerLogicalWidth, bordersPlusPadding,
3528 logicalLeftLength, logicalRightLength, marginLogicalLeft, marginLogicalRight,
3531 if (computedValues.m_extent < minValues.m_extent) {
3532 computedValues.m_extent = minValues.m_extent;
3533 computedValues.m_position = minValues.m_position;
3534 computedValues.m_margins.m_start = minValues.m_margins.m_start;
3535 computedValues.m_margins.m_end = minValues.m_margins.m_end;
3539 #if ENABLE(CSS_GRID_LAYOUT)
3540 if (!style().hasStaticInlinePosition(isHorizontal))
3541 computedValues.m_position += extraInlineOffset();
3544 computedValues.m_extent += bordersPlusPadding;
3545 if (is<RenderBox>(containerBlock)) {
3546 auto& containingBox = downcast<RenderBox>(containerBlock);
3547 if (containingBox.shouldPlaceBlockDirectionScrollbarOnLeft())
3548 computedValues.m_position += containingBox.verticalScrollbarWidth();
3551 // Adjust logicalLeft if we need to for the flipped version of our writing mode in regions.
3552 // FIXME: Add support for other types of objects as containerBlock, not only RenderBlock.
3553 RenderFlowThread* flowThread = flowThreadContainingBlock();
3554 if (flowThread && !region && isWritingModeRoot() && isHorizontalWritingMode() == containerBlock.isHorizontalWritingMode() && is<RenderBlock>(containerBlock)) {
3555 ASSERT(containerBlock.canHaveBoxInfoInRegion());
3556 LayoutUnit logicalLeftPos = computedValues.m_position;
3557 const RenderBlock& renderBlock = downcast<RenderBlock>(containerBlock);
3558 LayoutUnit cbPageOffset = renderBlock.offsetFromLogicalTopOfFirstPage();
3559 RenderRegion* cbRegion = renderBlock.regionAtBlockOffset(cbPageOffset);
3561 RenderBoxRegionInfo* boxInfo = renderBlock.renderBoxRegionInfo(cbRegion);
3563 logicalLeftPos += boxInfo->logicalLeft();
3564 computedValues.m_position = logicalLeftPos;
3570 static void computeLogicalLeftPositionedOffset(LayoutUnit& logicalLeftPos, const RenderBox* child, LayoutUnit logicalWidthValue, const RenderBoxModelObject& containerBlock, LayoutUnit containerLogicalWidth)
3572 // Deal with differing writing modes here. Our offset needs to be in the containing block's coordinate space. If the containing block is flipped
3573 // along this axis, then we need to flip the coordinate. This can only happen if the containing block is both a flipped mode and perpendicular to us.
3574 if (containerBlock.isHorizontalWritingMode() != child->isHorizontalWritingMode() && containerBlock.style().isFlippedBlocksWritingMode()) {
3575 logicalLeftPos = containerLogicalWidth - logicalWidthValue - logicalLeftPos;
3576 logicalLeftPos += (child->isHorizontalWritingMode() ? containerBlock.borderRight() : containerBlock.borderBottom());
3578 logicalLeftPos += (child->isHorizontalWritingMode() ? containerBlock.borderLeft() : containerBlock.borderTop());
3581 void RenderBox::computePositionedLogicalWidthUsing(SizeType widthType, Length logicalWidth, const RenderBoxModelObject& containerBlock, TextDirection containerDirection,
3582 LayoutUnit containerLogicalWidth, LayoutUnit bordersPlusPadding,
3583 Length logicalLeft, Length logicalRight, Length marginLogicalLeft, Length marginLogicalRight,
3584 LogicalExtentComputedValues& computedValues) const
3586 ASSERT(widthType == MinSize || widthType == MainOrPreferredSize || !logicalWidth.isAuto());
3587 if (widthType == MinSize && logicalWidth.isAuto())
3588 logicalWidth = Length(0, Fixed);
3589 else if (logicalWidth.isIntrinsic())
3590 logicalWidth = Length(computeIntrinsicLogicalWidthUsing(logicalWidth, containerLogicalWidth, bordersPlusPadding) - bordersPlusPadding, Fixed);
3592 // 'left' and 'right' cannot both be 'auto' because one would of been
3593 // converted to the static position already
3594 ASSERT(!(logicalLeft.isAuto() && logicalRight.isAuto()));
3596 LayoutUnit logicalLeftValue = 0;
3598 const LayoutUnit containerRelativeLogicalWidth = containingBlockLogicalWidthForPositioned(containerBlock, nullptr, false);
3600 bool logicalWidthIsAuto = logicalWidth.isIntrinsicOrAuto();
3601 bool logicalLeftIsAuto = logicalLeft.isAuto();
3602 bool logicalRightIsAuto = logicalRight.isAuto();
3603 LayoutUnit& marginLogicalLeftValue = style().isLeftToRightDirection() ? computedValues.m_margins.m_start : computedValues.m_margins.m_end;
3604 LayoutUnit& marginLogicalRightValue = style().isLeftToRightDirection() ? computedValues.m_margins.m_end : computedValues.m_margins.m_start;
3606 if (!logicalLeftIsAuto && !logicalWidthIsAuto && !logicalRightIsAuto) {
3607 /*-----------------------------------------------------------------------*\
3608 * If none of the three is 'auto': If both 'margin-left' and 'margin-
3609 * right' are 'auto', solve the equation under the extra constraint that
3610 * the two margins get equal values, unless this would make them negative,
3611 * in which case when direction of the containing block is 'ltr' ('rtl'),
3612 * set 'margin-left' ('margin-right') to zero and solve for 'margin-right'
3613 * ('margin-left'). If one of 'margin-left' or 'margin-right' is 'auto',
3614 * solve the equation for that value. If the values are over-constrained,
3615 * ignore the value for 'left' (in case the 'direction' property of the
3616 * containing block is 'rtl') or 'right' (in case 'direction' is 'ltr')
3617 * and solve for that value.
3618 \*-----------------------------------------------------------------------*/
3619 // NOTE: It is not necessary to solve for 'right' in the over constrained
3620 // case because the value is not used for any further calculations.
3622 logicalLeftValue = valueForLength(logicalLeft, containerLogicalWidth);
3623 computedValues.m_extent = adjustContentBoxLogicalWidthForBoxSizing(valueForLength(logicalWidth, containerLogicalWidth));
3625 const LayoutUnit availableSpace = containerLogicalWidth - (logicalLeftValue + computedValues.m_extent + valueForLength(logicalRight, containerLogicalWidth) + bordersPlusPadding);
3627 // Margins are now the only unknown
3628 if (marginLogicalLeft.isAuto() && marginLogicalRight.isAuto()) {
3629 // Both margins auto, solve for equality
3630 if (availableSpace >= 0) {
3631 marginLogicalLeftValue = availableSpace / 2; // split the difference
3632 marginLogicalRightValue = availableSpace - marginLogicalLeftValue; // account for odd valued differences
3634 // Use the containing block's direction rather than the parent block's
3635 // per CSS 2.1 reference test abspos-non-replaced-width-margin-000.
3636 if (containerDirection == LTR) {
3637 marginLogicalLeftValue = 0;
3638 marginLogicalRightValue = availableSpace; // will be negative
3640 marginLogicalLeftValue = availableSpace; // will be negative
3641 marginLogicalRightValue = 0;
3644 } else if (marginLogicalLeft.isAuto()) {
3645 // Solve for left margin
3646 marginLogicalRightValue = valueForLength(marginLogicalRight, containerRelativeLogicalWidth);
3647 marginLogicalLeftValue = availableSpace - marginLogicalRightValue;
3648 } else if (marginLogicalRight.isAuto()) {
3649 // Solve for right margin
3650 marginLogicalLeftValue = valueForLength(marginLogicalLeft, containerRelativeLogicalWidth);
3651 marginLogicalRightValue = availableSpace - marginLogicalLeftValue;
3653 // Over-constrained, solve for left if direction is RTL
3654 marginLogicalLeftValue = valueForLength(marginLogicalLeft, containerRelativeLogicalWidth);
3655 marginLogicalRightValue = valueForLength(marginLogicalRight, containerRelativeLogicalWidth);
3657 // Use the containing block's direction rather than the parent block's
3658 // per CSS 2.1 reference test abspos-non-replaced-width-margin-000.
3659 if (containerDirection == RTL)
3660 logicalLeftValue = (availableSpace + logicalLeftValue) - marginLogicalLeftValue - marginLogicalRightValue;
3663 /*--------------------------------------------------------------------*\
3664 * Otherwise, set 'auto' values for 'margin-left' and 'margin-right'
3665 * to 0, and pick the one of the following six rules that applies.
3667 * 1. 'left' and 'width' are 'auto' and 'right' is not 'auto', then the
3668 * width is shrink-to-fit. Then solve for 'left'
3670 * OMIT RULE 2 AS IT SHOULD NEVER BE HIT
3671 * ------------------------------------------------------------------
3672 * 2. 'left' and 'right' are 'auto' and 'width' is not 'auto', then if
3673 * the 'direction' property of the containing block is 'ltr' set
3674 * 'left' to the static position, otherwise set 'right' to the
3675 * static position. Then solve for 'left' (if 'direction is 'rtl')
3676 * or 'right' (if 'direction' is 'ltr').
3677 * ------------------------------------------------------------------
3679 * 3. 'width' and 'right' are 'auto' and 'left' is not 'auto', then the
3680 * width is shrink-to-fit . Then solve for 'right'
3681 * 4. 'left' is 'auto', 'width' and 'right' are not 'auto', then solve
3683 * 5. 'width' is 'auto', 'left' and 'right' are not 'auto', then solve
3685 * 6. 'right' is 'auto', 'left' and 'width' are not 'auto', then solve
3688 * Calculation of the shrink-to-fit width is similar to calculating the
3689 * width of a table cell using the automatic table layout algorithm.
3690 * Roughly: calculate the preferred width by formatting the content
3691 * without breaking lines other than where explicit line breaks occur,
3692 * and also calculate the preferred minimum width, e.g., by trying all
3693 * possible line breaks. CSS 2.1 does not define the exact algorithm.
3694 * Thirdly, calculate the available width: this is found by solving
3695 * for 'width' after setting 'left' (in case 1) or 'right' (in case 3)
3698 * Then the shrink-to-fit width is:
3699 * min(max(preferred minimum width, available width), preferred width).
3700 \*--------------------------------------------------------------------*/
3701 // NOTE: For rules 3 and 6 it is not necessary to solve for 'right'
3702 // because the value is not used for any further calculations.
3704 // Calculate margins, 'auto' margins are ignored.
3705 marginLogicalLeftValue = minimumValueForLength(marginLogicalLeft, containerRelativeLogicalWidth);
3706 marginLogicalRightValue = minimumValueForLength(marginLogicalRight, containerRelativeLogicalWidth);
3708 const LayoutUnit availableSpace = containerLogicalWidth - (marginLogicalLeftValue + marginLogicalRightValue + bordersPlusPadding);
3710 // FIXME: Is there a faster way to find the correct case?
3711 // Use rule/case that applies.
3712 if (logicalLeftIsAuto && logicalWidthIsAuto && !logicalRightIsAuto) {
3713 // RULE 1: (use shrink-to-fit for width, and solve of left)
3714 LayoutUnit logicalRightValue = valueForLength(logicalRight, containerLogicalWidth);
3716 // FIXME: would it be better to have shrink-to-fit in one step?
3717 LayoutUnit preferredWidth = maxPreferredLogicalWidth() - bordersPlusPadding;
3718 LayoutUnit preferredMinWidth = minPreferredLogicalWidth() - bordersPlusPadding;
3719 LayoutUnit availableWidth = availableSpace - logicalRightValue;
3720 computedValues.m_extent = std::min(std::max(preferredMinWidth, availableWidth), preferredWidth);
3721 logicalLeftValue = availableSpace - (computedValues.m_extent + logicalRightValue);
3722 } else if (!logicalLeftIsAuto && logicalWidthIsAuto && logicalRightIsAuto) {
3723 // RULE 3: (use shrink-to-fit for width, and no need solve of right)
3724 logicalLeftValue = valueForLength(logicalLeft, containerLogicalWidth);
3726 // FIXME: would it be better to have shrink-to-fit in one step?
3727 LayoutUnit preferredWidth = maxPreferredLogicalWidth() - bordersPlusPadding;
3728 LayoutUnit preferredMinWidth = minPreferredLogicalWidth() - bordersPlusPadding;
3729 LayoutUnit availableWidth = availableSpace - logicalLeftValue;
3730 computedValues.m_extent = std::min(std::max(preferredMinWidth, availableWidth), preferredWidth);
3731 } else if (logicalLeftIsAuto && !logicalWidthIsAuto && !logicalRightIsAuto) {
3732 // RULE 4: (solve for left)
3733 computedValues.m_extent = adjustContentBoxLogicalWidthForBoxSizing(valueForLength(logicalWidth, containerLogicalWidth));
3734 logicalLeftValue = availableSpace - (computedValues.m_extent + valueForLength(logicalRight, containerLogicalWidth));
3735 } else if (!logicalLeftIsAuto && logicalWidthIsAuto && !logicalRightIsAuto) {
3736 // RULE 5: (solve for width)
3737 logicalLeftValue = valueForLength(logicalLeft, containerLogicalWidth);
3738 computedValues.m_extent = availableSpace - (logicalLeftValue + valueForLength(logicalRight, containerLogicalWidth));
3739 } else if (!logicalLeftIsAuto && !logicalWidthIsAuto && logicalRightIsAuto) {
3740 // RULE 6: (no need solve for right)
3741 logicalLeftValue = valueForLength(logicalLeft, containerLogicalWidth);
3742 computedValues.m_extent = adjustContentBoxLogicalWidthForBoxSizing(valueForLength(logicalWidth, containerLogicalWidth));
3746 // Use computed values to calculate the horizontal position.
3748 // FIXME: This hack is needed to calculate the logical left position for a 'rtl' relatively
3749 // positioned, inline because right now, it is using the logical left position
3750 // of the first line box when really it should use the last line box. When
3751 // this is fixed elsewhere, this block should be removed.
3752 if (is<RenderInline>(containerBlock) && !containerBlock.style().isLeftToRightDirection()) {
3753 const auto& flow = downcast<RenderInline>(containerBlock);
3754 InlineFlowBox* firstLine = flow.firstLineBox();
3755 InlineFlowBox* lastLine = flow.lastLineBox();
3756 if (firstLine && lastLine && firstLine != lastLine) {
3757 computedValues.m_position = logicalLeftValue + marginLogicalLeftValue + lastLine->borderLogicalLeft() + (lastLine->logicalLeft() - firstLine->logicalLeft());
3762 computedValues.m_position = logicalLeftValue + marginLogicalLeftValue;
3763 computeLogicalLeftPositionedOffset(computedValues.m_position, this, computedValues.m_extent, containerBlock, containerLogicalWidth);
3766 static void computeBlockStaticDistance(Length& logicalTop, Length& logicalBottom, const RenderBox* child, const RenderBoxModelObject& containerBlock)
3768 if (!logicalTop.isAuto() || !logicalBottom.isAuto())
3771 // FIXME: The static distance computation has not been patched for mixed writing modes.
3772 LayoutUnit staticLogicalTop = child->layer()->staticBlockPosition() - containerBlock.borderBefore();
3773 for (RenderElement* container = child->parent(); container && container != &containerBlock; container = container->container()) {
3774 if (!is<RenderBox>(*container))
3776 const auto& renderBox = downcast<RenderBox>(*container);
3777 if (!is<RenderTableRow>(renderBox))
3778 staticLogicalTop += renderBox.logicalTop();
3779 if (renderBox.isInFlowPositioned())
3780 staticLogicalTop += renderBox.isHorizontalWritingMode() ? renderBox.offsetForInFlowPosition().height() : renderBox.offsetForInFlowPosition().width();
3782 logicalTop.setValue(Fixed, staticLogicalTop);
3785 void RenderBox::computePositionedLogicalHeight(LogicalExtentComputedValues& computedValues) const
3788 computePositionedLogicalHeightReplaced(computedValues);
3792 // The following is based off of the W3C Working Draft from April 11, 2006 of
3793 // CSS 2.1: Section 10.6.4 "Absolutely positioned, non-replaced elements"
3794 // <http://www.w3.org/TR/2005/WD-CSS21-20050613/visudet.html#abs-non-replaced-height>
3795 // (block-style-comments in this function and in computePositionedLogicalHeightUsing()
3796 // correspond to text from the spec)
3799 // We don't use containingBlock(), since we may be positioned by an enclosing relpositioned inline.
3800 const RenderBoxModelObject& containerBlock = downcast<RenderBoxModelObject>(*container());
3802 const LayoutUnit containerLogicalHeight = containingBlockLogicalHeightForPositioned(containerBlock);
3804 const RenderStyle& styleToUse = style();
3805 const LayoutUnit bordersPlusPadding = borderAndPaddingLogicalHeight();
3806 const Length marginBefore = styleToUse.marginBefore();
3807 const Length marginAfter = styleToUse.marginAfter();
3808 Length logicalTopLength = styleToUse.logicalTop();
3809 Length logicalBottomLength = styleToUse.logicalBottom();
3811 /*---------------------------------------------------------------------------*\
3812 * For the purposes of this section and the next, the term "static position"
3813 * (of an element) refers, roughly, to the position an element would have had
3814 * in the normal flow. More precisely, the static position for 'top' is the
3815 * distance from the top edge of the containing block to the top margin edge
3816 * of a hypothetical box that would have been the first box of the element if
3817 * its 'position' property had been 'static' and 'float' had been 'none'. The
3818 * value is negative if the hypothetical box is above the containing block.