blob: 715839fb5fce529c943f1971a8a2629b6622c4cd [file] [log] [blame]
/*
* This file is part of the render object implementation for KHTML.
*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* Copyright (C) 2003 Apple Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "config.h"
#include "RenderDeprecatedFlexibleBox.h"
#include "FontCascade.h"
#include "LayoutRepainter.h"
#include "RenderIterator.h"
#include "RenderLayer.h"
#include "RenderLayoutState.h"
#include "RenderView.h"
#include <wtf/IsoMallocInlines.h>
#include <wtf/StdLibExtras.h>
#include <wtf/unicode/CharacterNames.h>
namespace WebCore {
WTF_MAKE_ISO_ALLOCATED_IMPL(RenderDeprecatedFlexibleBox);
class FlexBoxIterator {
public:
FlexBoxIterator(RenderDeprecatedFlexibleBox* parent)
: m_box(parent)
, m_largestOrdinal(1)
{
if (m_box->style().boxOrient() == BoxOrient::Horizontal && !m_box->style().isLeftToRightDirection())
m_forward = m_box->style().boxDirection() != BoxDirection::Normal;
else
m_forward = m_box->style().boxDirection() == BoxDirection::Normal;
if (!m_forward) {
// No choice, since we're going backwards, we have to find out the highest ordinal up front.
RenderBox* child = m_box->firstChildBox();
while (child) {
if (child->style().boxOrdinalGroup() > m_largestOrdinal)
m_largestOrdinal = child->style().boxOrdinalGroup();
child = child->nextSiblingBox();
}
}
reset();
}
void reset()
{
m_currentChild = nullptr;
m_ordinalIteration = std::numeric_limits<unsigned>::max();
}
RenderBox* first()
{
reset();
return next();
}
RenderBox* next()
{
do {
if (!m_currentChild) {
++m_ordinalIteration;
if (!m_ordinalIteration)
m_currentOrdinal = m_forward ? 1 : m_largestOrdinal;
else {
if (m_ordinalIteration > m_ordinalValues.size())
return nullptr;
// Only copy+sort the values once per layout even if the iterator is reset.
if (static_cast<size_t>(m_ordinalValues.size()) != m_sortedOrdinalValues.size()) {
m_sortedOrdinalValues = copyToVector(m_ordinalValues);
std::sort(m_sortedOrdinalValues.begin(), m_sortedOrdinalValues.end());
}
m_currentOrdinal = m_forward ? m_sortedOrdinalValues[m_ordinalIteration - 1] : m_sortedOrdinalValues[m_sortedOrdinalValues.size() - m_ordinalIteration];
}
m_currentChild = m_forward ? m_box->firstChildBox() : m_box->lastChildBox();
} else
m_currentChild = m_forward ? m_currentChild->nextSiblingBox() : m_currentChild->previousSiblingBox();
if (m_currentChild && notFirstOrdinalValue())
m_ordinalValues.add(m_currentChild->style().boxOrdinalGroup());
} while (!m_currentChild || m_currentChild->isExcludedFromNormalLayout() || (!m_currentChild->isAnonymous()
&& m_currentChild->style().boxOrdinalGroup() != m_currentOrdinal));
return m_currentChild;
}
private:
bool notFirstOrdinalValue()
{
unsigned int firstOrdinalValue = m_forward ? 1 : m_largestOrdinal;
return m_currentOrdinal == firstOrdinalValue && m_currentChild->style().boxOrdinalGroup() != firstOrdinalValue;
}
RenderDeprecatedFlexibleBox* m_box;
RenderBox* m_currentChild;
bool m_forward;
unsigned m_currentOrdinal;
unsigned m_largestOrdinal;
HashSet<unsigned> m_ordinalValues;
Vector<unsigned> m_sortedOrdinalValues;
unsigned m_ordinalIteration;
};
RenderDeprecatedFlexibleBox::RenderDeprecatedFlexibleBox(Element& element, RenderStyle&& style)
: RenderBlock(element, WTFMove(style), 0)
{
setChildrenInline(false); // All of our children must be block-level
m_stretchingChildren = false;
}
RenderDeprecatedFlexibleBox::~RenderDeprecatedFlexibleBox() = default;
static LayoutUnit marginWidthForChild(RenderBox* child)
{
// A margin basically has three types: fixed, percentage, and auto (variable).
// Auto and percentage margins simply become 0 when computing min/max width.
// Fixed margins can be added in as is.
Length marginLeft = child->style().marginLeft();
Length marginRight = child->style().marginRight();
LayoutUnit margin;
if (marginLeft.isFixed())
margin += marginLeft.value();
if (marginRight.isFixed())
margin += marginRight.value();
return margin;
}
static bool childDoesNotAffectWidthOrFlexing(RenderObject* child)
{
// Positioned children and collapsed children don't affect the min/max width.
return child->isOutOfFlowPositioned() || child->style().visibility() == Visibility::Collapse;
}
static LayoutUnit widthForChild(RenderBox* child)
{
if (child->hasOverridingLogicalWidth())
return child->overridingLogicalWidth();
return child->logicalWidth();
}
static LayoutUnit heightForChild(RenderBox* child)
{
if (child->hasOverridingLogicalHeight())
return child->overridingLogicalHeight();
return child->logicalHeight();
}
static LayoutUnit contentWidthForChild(RenderBox* child)
{
return std::max<LayoutUnit>(0, widthForChild(child) - child->borderAndPaddingLogicalWidth());
}
static LayoutUnit contentHeightForChild(RenderBox* child)
{
return std::max<LayoutUnit>(0, heightForChild(child) - child->borderAndPaddingLogicalHeight());
}
void RenderDeprecatedFlexibleBox::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
{
auto* oldStyle = hasInitializedStyle() ? &style() : nullptr;
if (oldStyle) {
auto hadLineClamp = !oldStyle->lineClamp().isNone();
auto hasLineClamp = !newStyle.lineClamp().isNone();
if (hasLineClamp != hadLineClamp) {
for (auto& child : childrenOfType<RenderBlockFlow>(*this))
child.invalidateLineLayoutPath();
if (hadLineClamp)
clearLineClamp();
}
}
RenderBlock::styleWillChange(diff, newStyle);
}
void RenderDeprecatedFlexibleBox::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
{
auto addScrollbarWidth = [&]() {
LayoutUnit scrollbarWidth = intrinsicScrollbarLogicalWidth();
maxLogicalWidth += scrollbarWidth;
minLogicalWidth += scrollbarWidth;
};
if (shouldApplySizeContainment()) {
addScrollbarWidth();
return;
}
if (hasMultipleLines() || isVertical()) {
for (RenderBox* child = firstChildBox(); child; child = child->nextSiblingBox()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
LayoutUnit margin = marginWidthForChild(child);
LayoutUnit width = child->minPreferredLogicalWidth() + margin;
minLogicalWidth = std::max(width, minLogicalWidth);
width = child->maxPreferredLogicalWidth() + margin;
maxLogicalWidth = std::max(width, maxLogicalWidth);
}
} else {
for (RenderBox* child = firstChildBox(); child; child = child->nextSiblingBox()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
LayoutUnit margin = marginWidthForChild(child);
minLogicalWidth += child->minPreferredLogicalWidth() + margin;
maxLogicalWidth += child->maxPreferredLogicalWidth() + margin;
}
}
maxLogicalWidth = std::max(minLogicalWidth, maxLogicalWidth);
addScrollbarWidth();
}
void RenderDeprecatedFlexibleBox::computePreferredLogicalWidths()
{
ASSERT(preferredLogicalWidthsDirty());
m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = 0;
if (style().width().isFixed() && style().width().value() > 0)
m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = adjustContentBoxLogicalWidthForBoxSizing(style().width());
else
computeIntrinsicLogicalWidths(m_minPreferredLogicalWidth, m_maxPreferredLogicalWidth);
RenderBox::computePreferredLogicalWidths(style().minWidth(), style().maxWidth(), borderAndPaddingLogicalWidth());
setPreferredLogicalWidthsDirty(false);
}
// Use an inline capacity of 8, since flexbox containers usually have less than 8 children.
typedef Vector<LayoutRect, 8> ChildFrameRects;
typedef Vector<LayoutSize, 8> ChildLayoutDeltas;
static void appendChildFrameRects(RenderDeprecatedFlexibleBox* box, ChildFrameRects& childFrameRects)
{
FlexBoxIterator iterator(box);
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (!child->isOutOfFlowPositioned())
childFrameRects.append(child->frameRect());
}
}
static void appendChildLayoutDeltas(RenderDeprecatedFlexibleBox* box, ChildLayoutDeltas& childLayoutDeltas)
{
FlexBoxIterator iterator(box);
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (!child->isOutOfFlowPositioned())
childLayoutDeltas.append(LayoutSize());
}
}
static void repaintChildrenDuringLayoutIfMoved(RenderDeprecatedFlexibleBox* box, const ChildFrameRects& oldChildRects)
{
size_t childIndex = 0;
FlexBoxIterator iterator(box);
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (child->isOutOfFlowPositioned())
continue;
// If the child moved, we have to repaint it as well as any floating/positioned
// descendants. An exception is if we need a layout. In this case, we know we're going to
// repaint ourselves (and the child) anyway.
if (!box->selfNeedsLayout() && child->checkForRepaintDuringLayout())
child->repaintDuringLayoutIfMoved(oldChildRects[childIndex]);
++childIndex;
}
ASSERT(childIndex == oldChildRects.size());
}
void RenderDeprecatedFlexibleBox::layoutBlock(bool relayoutChildren, LayoutUnit)
{
ASSERT(needsLayout());
if (!relayoutChildren && simplifiedLayout())
return;
LayoutRepainter repainter(*this, checkForRepaintDuringLayout());
{
LayoutStateMaintainer statePusher(*this, locationOffset(), hasTransform() || hasReflection() || style().isFlippedBlocksWritingMode());
resetLogicalHeightBeforeLayoutIfNeeded();
preparePaginationBeforeBlockLayout(relayoutChildren);
LayoutSize previousSize = size();
updateLogicalWidth();
updateLogicalHeight();
if (previousSize != size()
|| (parent()->isDeprecatedFlexibleBox() && parent()->style().boxOrient() == BoxOrient::Horizontal
&& parent()->style().boxAlign() == BoxAlignment::Stretch))
relayoutChildren = true;
setHeight(0);
m_stretchingChildren = false;
#if ASSERT_ENABLED
LayoutSize oldLayoutDelta = view().frameView().layoutContext().layoutDelta();
#endif
// Fieldsets need to find their legend and position it inside the border of the object.
// The legend then gets skipped during normal layout. The same is true for ruby text.
// It doesn't get included in the normal layout process but is instead skipped.
layoutExcludedChildren(relayoutChildren);
ChildFrameRects oldChildRects;
appendChildFrameRects(this, oldChildRects);
if (isHorizontal())
layoutHorizontalBox(relayoutChildren);
else
layoutVerticalBox(relayoutChildren);
repaintChildrenDuringLayoutIfMoved(this, oldChildRects);
ASSERT(view().frameView().layoutContext().layoutDeltaMatches(oldLayoutDelta));
LayoutUnit oldClientAfterEdge = clientLogicalBottom();
updateLogicalHeight();
if (previousSize.height() != height())
relayoutChildren = true;
layoutPositionedObjects(relayoutChildren || isDocumentElementRenderer());
computeOverflow(oldClientAfterEdge);
}
updateLayerTransform();
auto* layoutState = view().frameView().layoutContext().layoutState();
if (layoutState && layoutState->pageLogicalHeight())
setPageLogicalOffset(layoutState->pageLogicalOffset(this, logicalTop()));
// Update our scrollbars if we're overflow:auto/scroll/hidden now that we know if
// we overflow or not.
updateScrollInfoAfterLayout();
// Repaint with our new bounds if they are different from our old bounds.
repainter.repaintAfterLayout();
clearNeedsLayout();
}
// The first walk over our kids is to find out if we have any flexible children.
static void gatherFlexChildrenInfo(FlexBoxIterator& iterator, bool relayoutChildren, unsigned int& highestFlexGroup, unsigned int& lowestFlexGroup, bool& haveFlex)
{
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
// Check to see if this child flexes.
if (!childDoesNotAffectWidthOrFlexing(child) && child->style().boxFlex() > 0.0f) {
// We always have to lay out flexible objects again, since the flex distribution
// may have changed, and we need to reallocate space.
child->clearOverridingContentSize();
if (!relayoutChildren)
child->setChildNeedsLayout(MarkOnlyThis);
haveFlex = true;
unsigned flexGroup = child->style().boxFlexGroup();
if (lowestFlexGroup == 0)
lowestFlexGroup = flexGroup;
if (flexGroup < lowestFlexGroup)
lowestFlexGroup = flexGroup;
if (flexGroup > highestFlexGroup)
highestFlexGroup = flexGroup;
}
}
}
static void layoutChildIfNeededApplyingDelta(RenderBox* child, const LayoutSize& layoutDelta)
{
if (!child->needsLayout())
return;
child->view().frameView().layoutContext().addLayoutDelta(layoutDelta);
child->layoutIfNeeded();
child->view().frameView().layoutContext().addLayoutDelta(-layoutDelta);
}
void RenderDeprecatedFlexibleBox::layoutHorizontalBox(bool relayoutChildren)
{
LayoutUnit toAdd = borderBottom() + paddingBottom() + horizontalScrollbarHeight();
LayoutUnit yPos = borderTop() + paddingTop();
LayoutUnit xPos = borderLeft() + paddingLeft();
bool heightSpecified = false;
LayoutUnit oldHeight;
LayoutUnit remainingSpace;
FlexBoxIterator iterator(this);
unsigned int highestFlexGroup = 0;
unsigned int lowestFlexGroup = 0;
bool haveFlex = false, flexingChildren = false;
gatherFlexChildrenInfo(iterator, relayoutChildren, highestFlexGroup, lowestFlexGroup, haveFlex);
beginUpdateScrollInfoAfterLayoutTransaction();
ChildLayoutDeltas childLayoutDeltas;
appendChildLayoutDeltas(this, childLayoutDeltas);
// We do 2 passes. The first pass is simply to lay everyone out at
// their preferred widths. The subsequent passes handle flexing the children.
// The first pass skips flexible objects completely.
do {
// Reset our height.
setHeight(yPos);
xPos = borderLeft() + paddingLeft();
size_t childIndex = 0;
// Our first pass is done without flexing. We simply lay the children
// out within the box. We have to do a layout first in order to determine
// our box's intrinsic height.
LayoutUnit maxAscent, maxDescent;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (relayoutChildren)
child->setChildNeedsLayout(MarkOnlyThis);
if (child->isOutOfFlowPositioned())
continue;
LayoutSize& childLayoutDelta = childLayoutDeltas[childIndex++];
// Compute the child's vertical margins.
child->computeAndSetBlockDirectionMargins(*this);
child->markForPaginationRelayoutIfNeeded();
// Apply the child's current layout delta.
layoutChildIfNeededApplyingDelta(child, childLayoutDelta);
// Update our height and overflow height.
if (style().boxAlign() == BoxAlignment::Baseline) {
LayoutUnit ascent = child->firstLineBaseline().value_or(child->height() + child->marginBottom());
ascent += child->marginTop();
LayoutUnit descent = (child->height() + child->verticalMarginExtent()) - ascent;
// Update our maximum ascent.
maxAscent = std::max(maxAscent, ascent);
// Update our maximum descent.
maxDescent = std::max(maxDescent, descent);
// Now update our height.
setHeight(std::max(yPos + maxAscent + maxDescent, height()));
}
else
setHeight(std::max(height(), yPos + child->height() + child->verticalMarginExtent()));
}
ASSERT(childIndex == childLayoutDeltas.size());
if (!iterator.first() && hasLineIfEmpty())
setHeight(height() + lineHeight(true, style().isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes));
setHeight(height() + toAdd);
oldHeight = height();
updateLogicalHeight();
relayoutChildren = false;
if (oldHeight != height())
heightSpecified = true;
// Now that our height is actually known, we can place our boxes.
childIndex = 0;
m_stretchingChildren = (style().boxAlign() == BoxAlignment::Stretch);
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (child->isOutOfFlowPositioned()) {
child->containingBlock()->insertPositionedObject(*child);
RenderLayer* childLayer = child->layer();
childLayer->setStaticInlinePosition(xPos); // FIXME: Not right for regions.
if (childLayer->staticBlockPosition() != yPos) {
childLayer->setStaticBlockPosition(yPos);
if (child->style().hasStaticBlockPosition(style().isHorizontalWritingMode()))
child->setChildNeedsLayout(MarkOnlyThis);
}
continue;
}
LayoutSize& childLayoutDelta = childLayoutDeltas[childIndex++];
if (child->style().visibility() == Visibility::Collapse) {
// visibility: collapsed children do not participate in our positioning.
// But we need to lay them out.
layoutChildIfNeededApplyingDelta(child, childLayoutDelta);
continue;
}
// We need to see if this child's height has changed, since we make block elements
// fill the height of a containing box by default.
// Now do a layout.
LayoutUnit oldChildHeight = child->height();
child->updateLogicalHeight();
if (oldChildHeight != child->height())
child->setChildNeedsLayout(MarkOnlyThis);
child->markForPaginationRelayoutIfNeeded();
layoutChildIfNeededApplyingDelta(child, childLayoutDelta);
// We can place the child now, using our value of box-align.
xPos += child->marginLeft();
LayoutUnit childY = yPos;
switch (style().boxAlign()) {
case BoxAlignment::Center:
childY += child->marginTop() + std::max<LayoutUnit>(0, (contentHeight() - (child->height() + child->verticalMarginExtent())) / 2);
break;
case BoxAlignment::Baseline: {
LayoutUnit ascent = child->firstLineBaseline().value_or(child->height() + child->marginBottom());
ascent += child->marginTop();
childY += child->marginTop() + (maxAscent - ascent);
break;
}
case BoxAlignment::End:
childY += contentHeight() - child->marginBottom() - child->height();
break;
default: // BoxAlignment::Start
childY += child->marginTop();
break;
}
placeChild(child, LayoutPoint(xPos, childY), &childLayoutDelta);
xPos += child->width() + child->marginRight();
}
ASSERT(childIndex == childLayoutDeltas.size());
remainingSpace = borderLeft() + paddingLeft() + contentWidth() - xPos;
m_stretchingChildren = false;
if (flexingChildren)
haveFlex = false; // We're done.
else if (haveFlex) {
// We have some flexible objects. See if we need to grow/shrink them at all.
if (!remainingSpace)
break;
// Allocate the remaining space among the flexible objects. If we are trying to
// grow, then we go from the lowest flex group to the highest flex group. For shrinking,
// we go from the highest flex group to the lowest group.
bool expanding = remainingSpace > 0;
unsigned int start = expanding ? lowestFlexGroup : highestFlexGroup;
unsigned int end = expanding? highestFlexGroup : lowestFlexGroup;
for (unsigned int i = start; i <= end && remainingSpace; i++) {
// Always start off by assuming the group can get all the remaining space.
LayoutUnit groupRemainingSpace = remainingSpace;
do {
// Flexing consists of multiple passes, since we have to change ratios every time an object hits its max/min-width
// For a given pass, we always start off by computing the totalFlex of all objects that can grow/shrink at all, and
// computing the allowed growth before an object hits its min/max width (and thus
// forces a totalFlex recomputation).
LayoutUnit groupRemainingSpaceAtBeginning = groupRemainingSpace;
float totalFlex = 0.0f;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (allowedChildFlex(child, expanding, i))
totalFlex += child->style().boxFlex();
}
LayoutUnit spaceAvailableThisPass = groupRemainingSpace;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
LayoutUnit allowedFlex = allowedChildFlex(child, expanding, i);
if (allowedFlex) {
LayoutUnit projectedFlex = (allowedFlex == LayoutUnit::max()) ? allowedFlex : LayoutUnit(allowedFlex * (totalFlex / child->style().boxFlex()));
spaceAvailableThisPass = expanding ? std::min(spaceAvailableThisPass, projectedFlex) : std::max(spaceAvailableThisPass, projectedFlex);
}
}
// The flex groups may not have any flexible objects this time around.
if (!spaceAvailableThisPass || totalFlex == 0.0f) {
// If we just couldn't grow/shrink any more, then it's time to transition to the next flex group.
groupRemainingSpace = 0;
continue;
}
// Now distribute the space to objects.
for (RenderBox* child = iterator.first(); child && spaceAvailableThisPass && totalFlex; child = iterator.next()) {
if (child->style().visibility() == Visibility::Collapse)
continue;
if (allowedChildFlex(child, expanding, i)) {
LayoutUnit spaceAdd = LayoutUnit(spaceAvailableThisPass * (child->style().boxFlex() / totalFlex));
if (spaceAdd) {
child->setOverridingLogicalWidth(widthForChild(child) + spaceAdd);
flexingChildren = true;
relayoutChildren = true;
}
spaceAvailableThisPass -= spaceAdd;
remainingSpace -= spaceAdd;
groupRemainingSpace -= spaceAdd;
totalFlex -= child->style().boxFlex();
}
}
if (groupRemainingSpace == groupRemainingSpaceAtBeginning) {
// This is not advancing, avoid getting stuck by distributing the remaining pixels.
LayoutUnit spaceAdd = groupRemainingSpace > 0 ? 1 : -1;
for (RenderBox* child = iterator.first(); child && groupRemainingSpace; child = iterator.next()) {
if (allowedChildFlex(child, expanding, i)) {
child->setOverridingLogicalWidth(widthForChild(child) + spaceAdd);
flexingChildren = true;
relayoutChildren = true;
remainingSpace -= spaceAdd;
groupRemainingSpace -= spaceAdd;
}
}
}
} while (absoluteValue(groupRemainingSpace) >= 1);
}
// We didn't find any children that could grow.
if (haveFlex && !flexingChildren)
haveFlex = false;
}
} while (haveFlex);
endAndCommitUpdateScrollInfoAfterLayoutTransaction();
if (remainingSpace > 0 && ((style().isLeftToRightDirection() && style().boxPack() != BoxPack::Start)
|| (!style().isLeftToRightDirection() && style().boxPack() != BoxPack::End))) {
// Children must be repositioned.
LayoutUnit offset;
if (style().boxPack() == BoxPack::Justify) {
// Determine the total number of children.
int totalChildren = 0;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
++totalChildren;
}
// Iterate over the children and space them out according to the
// justification level.
if (totalChildren > 1) {
--totalChildren;
bool firstChild = true;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
if (firstChild) {
firstChild = false;
continue;
}
offset += remainingSpace/totalChildren;
remainingSpace -= (remainingSpace/totalChildren);
--totalChildren;
placeChild(child, child->location() + LayoutSize(offset, 0_lu));
}
}
} else {
if (style().boxPack() == BoxPack::Center)
offset += remainingSpace / 2;
else // BoxPack::End for LTR, BoxPack::Start for RTL
offset += remainingSpace;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
placeChild(child, child->location() + LayoutSize(offset, 0_lu));
}
}
}
// So that the computeLogicalHeight in layoutBlock() knows to relayout positioned objects because of
// a height change, we revert our height back to the intrinsic height before returning.
if (heightSpecified)
setHeight(oldHeight);
}
void RenderDeprecatedFlexibleBox::layoutVerticalBox(bool relayoutChildren)
{
LayoutUnit yPos = borderTop() + paddingTop();
LayoutUnit toAdd = borderBottom() + paddingBottom() + horizontalScrollbarHeight();
bool heightSpecified = false;
LayoutUnit oldHeight;
LayoutUnit remainingSpace;
FlexBoxIterator iterator(this);
unsigned int highestFlexGroup = 0;
unsigned int lowestFlexGroup = 0;
bool haveFlex = false, flexingChildren = false;
gatherFlexChildrenInfo(iterator, relayoutChildren, highestFlexGroup, lowestFlexGroup, haveFlex);
// We confine the line clamp ugliness to vertical flexible boxes (thus keeping it out of
// mainstream block layout); this is not really part of the XUL box model.
bool haveLineClamp = !style().lineClamp().isNone();
if (haveLineClamp)
applyLineClamp(iterator, relayoutChildren);
beginUpdateScrollInfoAfterLayoutTransaction();
ChildLayoutDeltas childLayoutDeltas;
appendChildLayoutDeltas(this, childLayoutDeltas);
// We do 2 passes. The first pass is simply to lay everyone out at
// their preferred widths. The second pass handles flexing the children.
// Our first pass is done without flexing. We simply lay the children
// out within the box.
do {
setHeight(borderTop() + paddingTop());
LayoutUnit minHeight = height() + toAdd;
size_t childIndex = 0;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
// Make sure we relayout children if we need it.
if (!haveLineClamp && relayoutChildren)
child->setChildNeedsLayout(MarkOnlyThis);
if (child->isOutOfFlowPositioned()) {
child->containingBlock()->insertPositionedObject(*child);
RenderLayer* childLayer = child->layer();
childLayer->setStaticInlinePosition(borderStart() + paddingStart()); // FIXME: Not right for regions.
if (childLayer->staticBlockPosition() != height()) {
childLayer->setStaticBlockPosition(height());
if (child->style().hasStaticBlockPosition(style().isHorizontalWritingMode()))
child->setChildNeedsLayout(MarkOnlyThis);
}
continue;
}
LayoutSize& childLayoutDelta = childLayoutDeltas[childIndex++];
if (child->style().visibility() == Visibility::Collapse) {
// visibility: collapsed children do not participate in our positioning.
// But we need to lay them down.
layoutChildIfNeededApplyingDelta(child, childLayoutDelta);
continue;
}
// Compute the child's vertical margins.
child->computeAndSetBlockDirectionMargins(*this);
// Add in the child's marginTop to our height.
setHeight(height() + child->marginTop());
child->markForPaginationRelayoutIfNeeded();
// Now do a layout.
layoutChildIfNeededApplyingDelta(child, childLayoutDelta);
// We can place the child now, using our value of box-align.
LayoutUnit childX = borderLeft() + paddingLeft();
switch (style().boxAlign()) {
case BoxAlignment::Center:
case BoxAlignment::Baseline: // Baseline just maps to center for vertical boxes
childX += child->marginLeft() + std::max<LayoutUnit>(0, (contentWidth() - (child->width() + child->horizontalMarginExtent())) / 2);
break;
case BoxAlignment::End:
if (!style().isLeftToRightDirection())
childX += child->marginLeft();
else
childX += contentWidth() - child->marginRight() - child->width();
break;
default: // BoxAlignment::Start/BoxAlignment::Stretch
if (style().isLeftToRightDirection())
childX += child->marginLeft();
else
childX += contentWidth() - child->marginRight() - child->width();
break;
}
// Place the child.
placeChild(child, LayoutPoint(childX, height()), &childLayoutDelta);
setHeight(height() + child->height() + child->marginBottom());
}
ASSERT(childIndex == childLayoutDeltas.size());
yPos = height();
if (!iterator.first() && hasLineIfEmpty())
setHeight(height() + lineHeight(true, style().isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes));
setHeight(height() + toAdd);
// Negative margins can cause our height to shrink below our minimal height (border/padding).
// If this happens, ensure that the computed height is increased to the minimal height.
if (height() < minHeight)
setHeight(minHeight);
// Now we have to calc our height, so we know how much space we have remaining.
oldHeight = height();
updateLogicalHeight();
if (oldHeight != height())
heightSpecified = true;
remainingSpace = borderTop() + paddingTop() + contentHeight() - yPos;
if (flexingChildren)
haveFlex = false; // We're done.
else if (haveFlex) {
// We have some flexible objects. See if we need to grow/shrink them at all.
if (!remainingSpace)
break;
// Allocate the remaining space among the flexible objects. If we are trying to
// grow, then we go from the lowest flex group to the highest flex group. For shrinking,
// we go from the highest flex group to the lowest group.
bool expanding = remainingSpace > 0;
unsigned int start = expanding ? lowestFlexGroup : highestFlexGroup;
unsigned int end = expanding? highestFlexGroup : lowestFlexGroup;
for (unsigned int i = start; i <= end && remainingSpace; i++) {
// Always start off by assuming the group can get all the remaining space.
LayoutUnit groupRemainingSpace = remainingSpace;
do {
// Flexing consists of multiple passes, since we have to change ratios every time an object hits its max/min-width
// For a given pass, we always start off by computing the totalFlex of all objects that can grow/shrink at all, and
// computing the allowed growth before an object hits its min/max width (and thus
// forces a totalFlex recomputation).
LayoutUnit groupRemainingSpaceAtBeginning = groupRemainingSpace;
float totalFlex = 0.0f;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (allowedChildFlex(child, expanding, i))
totalFlex += child->style().boxFlex();
}
LayoutUnit spaceAvailableThisPass = groupRemainingSpace;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
LayoutUnit allowedFlex = allowedChildFlex(child, expanding, i);
if (allowedFlex) {
LayoutUnit projectedFlex = (allowedFlex == LayoutUnit::max()) ? allowedFlex : LayoutUnit(allowedFlex * (totalFlex / child->style().boxFlex()));
spaceAvailableThisPass = expanding ? std::min(spaceAvailableThisPass, projectedFlex) : std::max(spaceAvailableThisPass, projectedFlex);
}
}
// The flex groups may not have any flexible objects this time around.
if (!spaceAvailableThisPass || totalFlex == 0.0f) {
// If we just couldn't grow/shrink any more, then it's time to transition to the next flex group.
groupRemainingSpace = 0;
continue;
}
// Now distribute the space to objects.
for (RenderBox* child = iterator.first(); child && spaceAvailableThisPass && totalFlex; child = iterator.next()) {
if (allowedChildFlex(child, expanding, i)) {
LayoutUnit spaceAdd { spaceAvailableThisPass * (child->style().boxFlex() / totalFlex) };
if (spaceAdd) {
child->setOverridingLogicalHeight(heightForChild(child) + spaceAdd);
flexingChildren = true;
relayoutChildren = true;
}
spaceAvailableThisPass -= spaceAdd;
remainingSpace -= spaceAdd;
groupRemainingSpace -= spaceAdd;
totalFlex -= child->style().boxFlex();
}
}
if (groupRemainingSpace == groupRemainingSpaceAtBeginning) {
// This is not advancing, avoid getting stuck by distributing the remaining pixels.
LayoutUnit spaceAdd = groupRemainingSpace > 0 ? 1 : -1;
for (RenderBox* child = iterator.first(); child && groupRemainingSpace; child = iterator.next()) {
if (allowedChildFlex(child, expanding, i)) {
child->setOverridingLogicalHeight(heightForChild(child) + spaceAdd);
flexingChildren = true;
relayoutChildren = true;
remainingSpace -= spaceAdd;
groupRemainingSpace -= spaceAdd;
}
}
}
} while (absoluteValue(groupRemainingSpace) >= 1);
}
// We didn't find any children that could grow.
if (haveFlex && !flexingChildren)
haveFlex = false;
}
} while (haveFlex);
endAndCommitUpdateScrollInfoAfterLayoutTransaction();
if (style().boxPack() != BoxPack::Start && remainingSpace > 0) {
// Children must be repositioned.
LayoutUnit offset;
if (style().boxPack() == BoxPack::Justify) {
// Determine the total number of children.
int totalChildren = 0;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
++totalChildren;
}
// Iterate over the children and space them out according to the
// justification level.
if (totalChildren > 1) {
--totalChildren;
bool firstChild = true;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
if (firstChild) {
firstChild = false;
continue;
}
offset += remainingSpace/totalChildren;
remainingSpace -= (remainingSpace/totalChildren);
--totalChildren;
placeChild(child, child->location() + LayoutSize(0_lu, offset));
}
}
} else {
if (style().boxPack() == BoxPack::Center)
offset += remainingSpace / 2;
else // BoxPack::End
offset += remainingSpace;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
placeChild(child, child->location() + LayoutSize(0_lu, offset));
}
}
}
// So that the computeLogicalHeight in layoutBlock() knows to relayout positioned objects because of
// a height change, we revert our height back to the intrinsic height before returning.
if (heightSpecified)
setHeight(oldHeight);
}
static bool shouldIncludeLinesForParentLineCount(const RenderBlockFlow& blockFlow)
{
return !blockFlow.isFloatingOrOutOfFlowPositioned() && blockFlow.style().height().isAuto();
}
static void clearTruncation(RenderBlockFlow& blockFlow)
{
if (blockFlow.style().visibility() != Visibility::Visible)
return;
if (blockFlow.childrenInline() && blockFlow.hasMarkupTruncation()) {
blockFlow.setHasMarkupTruncation(false);
for (auto* box = blockFlow.firstRootBox(); box; box = box->nextRootBox())
box->clearTruncation();
return;
}
for (auto& child : childrenOfType<RenderBlockFlow>(blockFlow)) {
if (shouldIncludeLinesForParentLineCount(child))
clearTruncation(child);
}
}
static LegacyRootInlineBox* lineAtIndex(const RenderBlockFlow& flow, int i)
{
ASSERT(i >= 0);
if (flow.style().visibility() != Visibility::Visible)
return nullptr;
if (flow.childrenInline()) {
for (auto* box = flow.firstRootBox(); box; box = box->nextRootBox()) {
if (!i--)
return box;
}
return nullptr;
}
for (auto& blockFlow : childrenOfType<RenderBlockFlow>(flow)) {
if (!shouldIncludeLinesForParentLineCount(blockFlow))
continue;
if (LegacyRootInlineBox* box = lineAtIndex(blockFlow, i))
return box;
}
return nullptr;
}
static std::optional<LayoutUnit> getHeightForLineCount(const RenderBlockFlow& block, size_t lineCount, bool includeBottom, size_t& count)
{
if (block.style().visibility() != Visibility::Visible)
return { };
if (block.childrenInline()) {
for (auto* box = block.firstRootBox(); box; box = box->nextRootBox()) {
if (++count == lineCount)
return box->lineBottom() + (includeBottom ? (block.borderBottom() + block.paddingBottom()) : 0_lu);
}
} else {
RenderBox* normalFlowChildWithoutLines = nullptr;
for (auto* obj = block.firstChildBox(); obj; obj = obj->nextSiblingBox()) {
if (is<RenderBlockFlow>(*obj) && shouldIncludeLinesForParentLineCount(downcast<RenderBlockFlow>(*obj))) {
if (auto height = getHeightForLineCount(downcast<RenderBlockFlow>(*obj), lineCount, false, count))
return *height + obj->y() + (includeBottom ? (block.borderBottom() + block.paddingBottom()) : 0_lu);
} else if (!obj->isFloatingOrOutOfFlowPositioned())
normalFlowChildWithoutLines = obj;
}
if (normalFlowChildWithoutLines && !lineCount)
return normalFlowChildWithoutLines->y() + normalFlowChildWithoutLines->height();
}
return { };
}
static LayoutUnit heightForLineCount(const RenderBlockFlow& flow, size_t lineCount)
{
size_t count = 0;
if (auto height = getHeightForLineCount(flow, lineCount, true, count))
return *height;
return { };
}
static size_t lineCountFor(const RenderBlockFlow& blockFlow)
{
if (blockFlow.style().visibility() != Visibility::Visible)
return 0;
if (blockFlow.childrenInline())
return blockFlow.lineCount();
size_t count = 0;
for (auto& child : childrenOfType<RenderBlockFlow>(blockFlow)) {
if (blockFlow.isFloatingOrOutOfFlowPositioned() || !blockFlow.style().height().isAuto())
continue;
count += lineCountFor(child);
}
return count;
}
void RenderDeprecatedFlexibleBox::applyLineClamp(FlexBoxIterator& iterator, bool relayoutChildren)
{
size_t maxLineCount = 0;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
child->clearOverridingContentSize();
if (relayoutChildren || (child->isReplacedOrInlineBlock() && (child->style().width().isPercentOrCalculated() || child->style().height().isPercentOrCalculated()))
|| (child->style().height().isAuto() && is<RenderBlockFlow>(*child))) {
child->setChildNeedsLayout(MarkOnlyThis);
// Dirty all the positioned objects.
if (is<RenderBlockFlow>(*child)) {
downcast<RenderBlockFlow>(*child).markPositionedObjectsForLayout();
clearTruncation(downcast<RenderBlockFlow>(*child));
}
}
child->layoutIfNeeded();
if (child->style().height().isAuto() && is<RenderBlockFlow>(*child))
maxLineCount = std::max(maxLineCount, lineCountFor(downcast<RenderBlockFlow>(*child)));
}
// Get the number of lines and then alter all block flow children with auto height to use the
// specified height. We always try to leave room for at least one line.
auto lineClamp = style().lineClamp();
ASSERT(!lineClamp.isNone());
size_t numVisibleLines = lineClamp.value();
if (lineClamp.isPercentage()) {
float percentValue = lineClamp.value();
numVisibleLines = std::max<size_t>(1, (maxLineCount + 1) * percentValue / 100.f);
}
if (numVisibleLines >= maxLineCount)
return;
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child) || !child->style().height().isAuto() || !is<RenderBlockFlow>(*child))
continue;
RenderBlockFlow& blockChild = downcast<RenderBlockFlow>(*child);
auto lineCount = lineCountFor(blockChild);
if (lineCount <= numVisibleLines)
continue;
auto newHeight = heightForLineCount(blockChild, numVisibleLines);
if (newHeight == child->height())
continue;
child->setChildNeedsLayout(MarkOnlyThis);
child->setOverridingLogicalHeight(newHeight);
child->layoutIfNeeded();
// FIXME: For now don't support RTL.
if (style().direction() != TextDirection::LTR)
continue;
// Get the last line
LegacyRootInlineBox* lastLine = lineAtIndex(blockChild, lineCount - 1);
if (!lastLine)
continue;
LegacyRootInlineBox* lastVisibleLine = lineAtIndex(blockChild, numVisibleLines - 1);
if (!lastVisibleLine || !lastVisibleLine->firstChild())
continue;
const UChar ellipsisAndSpace[2] = { horizontalEllipsis, ' ' };
static MainThreadNeverDestroyed<const AtomString> ellipsisAndSpaceStr(ellipsisAndSpace, 2);
static MainThreadNeverDestroyed<const AtomString> ellipsisStr(&horizontalEllipsis, 1);
const RenderStyle& lineStyle = numVisibleLines == 1 ? firstLineStyle() : style();
const FontCascade& font = lineStyle.fontCascade();
// Get ellipsis width, and if the last child is an anchor, it will go after the ellipsis, so add in a space and the anchor width too
LayoutUnit totalWidth;
LegacyInlineBox* anchorBox = lastLine->lastChild();
auto& lastVisibleRenderer = lastVisibleLine->firstChild()->renderer();
if (anchorBox && anchorBox->renderer().style().isLink() && &lastVisibleRenderer != &anchorBox->renderer())
totalWidth = anchorBox->logicalWidth() + font.width(constructTextRun(ellipsisAndSpace, 2, style()));
else {
anchorBox = nullptr;
totalWidth = font.width(constructTextRun(&horizontalEllipsis, 1, style()));
}
// See if this width can be accommodated on the last visible line
RenderBlockFlow& destBlock = lastVisibleLine->blockFlow();
RenderBlockFlow& srcBlock = lastLine->blockFlow();
// FIXME: Directions of src/destBlock could be different from our direction and from one another.
if (!srcBlock.style().isLeftToRightDirection())
continue;
bool leftToRight = destBlock.style().isLeftToRightDirection();
if (!leftToRight)
continue;
LayoutUnit blockRightEdge = destBlock.logicalRightOffsetForLine(LayoutUnit(lastVisibleLine->y()), DoNotIndentText);
if (!lastVisibleLine->lineCanAccommodateEllipsis(leftToRight, blockRightEdge, lastVisibleLine->x() + lastVisibleLine->logicalWidth(), totalWidth))
continue;
// Let the truncation code kick in.
// FIXME: the text alignment should be recomputed after the width changes due to truncation.
LayoutUnit blockLeftEdge = destBlock.logicalLeftOffsetForLine(LayoutUnit(lastVisibleLine->y()), DoNotIndentText);
lastVisibleLine->placeEllipsis(anchorBox ? ellipsisAndSpaceStr : ellipsisStr, leftToRight, blockLeftEdge, blockRightEdge, totalWidth, anchorBox);
destBlock.setHasMarkupTruncation(true);
}
}
void RenderDeprecatedFlexibleBox::clearLineClamp()
{
FlexBoxIterator iterator(this);
for (RenderBox* child = iterator.first(); child; child = iterator.next()) {
if (childDoesNotAffectWidthOrFlexing(child))
continue;
child->clearOverridingContentSize();
if ((child->isReplacedOrInlineBlock() && (child->style().width().isPercentOrCalculated() || child->style().height().isPercentOrCalculated()))
|| (child->style().height().isAuto() && is<RenderBlockFlow>(*child))) {
child->setChildNeedsLayout();
if (is<RenderBlockFlow>(*child)) {
downcast<RenderBlockFlow>(*child).markPositionedObjectsForLayout();
clearTruncation(downcast<RenderBlockFlow>(*child));
}
}
}
}
void RenderDeprecatedFlexibleBox::placeChild(RenderBox* child, const LayoutPoint& location, LayoutSize* childLayoutDelta)
{
// Place the child and track the layout delta so we can apply it if we do another layout.
if (childLayoutDelta)
*childLayoutDelta += LayoutSize(child->x() - location.x(), child->y() - location.y());
child->setLocation(location);
}
LayoutUnit RenderDeprecatedFlexibleBox::allowedChildFlex(RenderBox* child, bool expanding, unsigned int group)
{
if (childDoesNotAffectWidthOrFlexing(child) || child->style().boxFlex() == 0.0f || child->style().boxFlexGroup() != group)
return 0;
if (expanding) {
if (isHorizontal()) {
// FIXME: For now just handle fixed values.
LayoutUnit maxWidth = LayoutUnit::max();
LayoutUnit width = contentWidthForChild(child);
if (!child->style().maxWidth().isUndefined() && child->style().maxWidth().isFixed())
maxWidth = child->style().maxWidth().value();
else if (child->style().maxWidth().type() == LengthType::Intrinsic)
maxWidth = child->maxPreferredLogicalWidth();
else if (child->style().maxWidth().isMinIntrinsic())
maxWidth = child->minPreferredLogicalWidth();
if (maxWidth == LayoutUnit::max())
return maxWidth;
return std::max<LayoutUnit>(0, maxWidth - width);
} else {
// FIXME: For now just handle fixed values.
LayoutUnit maxHeight = LayoutUnit::max();
LayoutUnit height = contentHeightForChild(child);
if (!child->style().maxHeight().isUndefined() && child->style().maxHeight().isFixed())
maxHeight = child->style().maxHeight().value();
if (maxHeight == LayoutUnit::max())
return maxHeight;
return std::max<LayoutUnit>(0, maxHeight - height);
}
}
// FIXME: For now just handle fixed values.
if (isHorizontal()) {
LayoutUnit minWidth = child->minPreferredLogicalWidth();
LayoutUnit width = contentWidthForChild(child);
if (child->style().minWidth().isFixed())
minWidth = child->style().minWidth().value();
else if (child->style().minWidth().type() == LengthType::Intrinsic)
minWidth = child->maxPreferredLogicalWidth();
else if (child->style().minWidth().isMinIntrinsic())
minWidth = child->minPreferredLogicalWidth();
else if (child->style().minWidth().isAuto())
minWidth = 0;
LayoutUnit allowedShrinkage = std::min<LayoutUnit>(0, minWidth - width);
return allowedShrinkage;
} else {
Length minHeight = child->style().minHeight();
if (minHeight.isFixed() || minHeight.isAuto()) {
LayoutUnit minHeight { child->style().minHeight().value() };
LayoutUnit height = contentHeightForChild(child);
LayoutUnit allowedShrinkage = std::min<LayoutUnit>(0, minHeight - height);
return allowedShrinkage;
}
}
return 0;
}
ASCIILiteral RenderDeprecatedFlexibleBox::renderName() const
{
if (isFloating())
return "RenderDeprecatedFlexibleBox (floating)"_s;
if (isOutOfFlowPositioned())
return "RenderDeprecatedFlexibleBox (positioned)"_s;
// FIXME: Temporary hack while the new generated content system is being implemented.
if (isPseudoElement())
return "RenderDeprecatedFlexibleBox (generated)"_s;
if (isAnonymous())
return "RenderDeprecatedFlexibleBox (generated)"_s;
if (isRelativelyPositioned())
return "RenderDeprecatedFlexibleBox (relative positioned)"_s;
return "RenderDeprecatedFlexibleBox"_s;
}
} // namespace WebCore