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/*
* Copyright (C) 2011 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "core/layout/LayoutGrid.h"
#include "core/layout/LayoutView.h"
#include "core/layout/TextAutosizer.h"
#include "core/paint/GridPainter.h"
#include "core/paint/PaintLayer.h"
#include "core/style/ComputedStyle.h"
#include "core/style/GridCoordinate.h"
#include "platform/LengthFunctions.h"
namespace blink {
static const int infinity = -1;
class GridItemWithSpan;
class GridTrack {
public:
GridTrack()
: m_baseSize(0)
, m_growthLimit(0)
, m_plannedSize(0)
, m_sizeDuringDistribution(0)
, m_infinitelyGrowable(false)
{
}
const LayoutUnit& baseSize() const
{
ASSERT(isGrowthLimitBiggerThanBaseSize());
return m_baseSize;
}
const LayoutUnit& growthLimit() const
{
ASSERT(isGrowthLimitBiggerThanBaseSize());
return m_growthLimit;
}
void setBaseSize(LayoutUnit baseSize)
{
m_baseSize = baseSize;
ensureGrowthLimitIsBiggerThanBaseSize();
}
void setGrowthLimit(LayoutUnit growthLimit)
{
m_growthLimit = growthLimit;
ensureGrowthLimitIsBiggerThanBaseSize();
}
bool growthLimitIsInfinite() const
{
return m_growthLimit == infinity;
}
bool infiniteGrowthPotential() const
{
return growthLimitIsInfinite() || m_infinitelyGrowable;
}
const LayoutUnit& plannedSize() const { return m_plannedSize; }
void setPlannedSize(const LayoutUnit& plannedSize)
{
ASSERT(plannedSize >= 0 || plannedSize == infinity);
m_plannedSize = plannedSize;
}
const LayoutUnit& sizeDuringDistribution() { return m_sizeDuringDistribution; }
void setSizeDuringDistribution(const LayoutUnit& sizeDuringDistribution)
{
ASSERT(sizeDuringDistribution >= 0);
m_sizeDuringDistribution = sizeDuringDistribution;
}
void growSizeDuringDistribution(const LayoutUnit& sizeDuringDistribution)
{
ASSERT(sizeDuringDistribution >= 0);
m_sizeDuringDistribution += sizeDuringDistribution;
}
bool infinitelyGrowable() const { return m_infinitelyGrowable; }
void setInfinitelyGrowable(bool infinitelyGrowable) { m_infinitelyGrowable = infinitelyGrowable; }
private:
bool isGrowthLimitBiggerThanBaseSize() const { return growthLimitIsInfinite() || m_growthLimit >= m_baseSize; }
void ensureGrowthLimitIsBiggerThanBaseSize()
{
if (m_growthLimit != infinity && m_growthLimit < m_baseSize)
m_growthLimit = m_baseSize;
}
LayoutUnit m_baseSize;
LayoutUnit m_growthLimit;
LayoutUnit m_plannedSize;
LayoutUnit m_sizeDuringDistribution;
bool m_infinitelyGrowable;
};
struct ContentAlignmentData {
STACK_ALLOCATED();
public:
ContentAlignmentData() {};
ContentAlignmentData(LayoutUnit position, LayoutUnit distribution)
: positionOffset(position)
, distributionOffset(distribution)
{
}
bool isValid() { return positionOffset >= 0 && distributionOffset >= 0; }
LayoutUnit positionOffset = -1;
LayoutUnit distributionOffset = -1;
};
enum TrackSizeRestriction {
AllowInfinity,
ForbidInfinity,
};
class LayoutGrid::GridIterator {
WTF_MAKE_NONCOPYABLE(GridIterator);
public:
// |direction| is the direction that is fixed to |fixedTrackIndex| so e.g
// GridIterator(m_grid, ForColumns, 1) will walk over the rows of the 2nd column.
GridIterator(const GridRepresentation& grid, GridTrackSizingDirection direction, size_t fixedTrackIndex, size_t varyingTrackIndex = 0)
: m_grid(grid)
, m_direction(direction)
, m_rowIndex((direction == ForColumns) ? varyingTrackIndex : fixedTrackIndex)
, m_columnIndex((direction == ForColumns) ? fixedTrackIndex : varyingTrackIndex)
, m_childIndex(0)
{
ASSERT(m_rowIndex < m_grid.size());
ASSERT(m_columnIndex < m_grid[0].size());
}
LayoutBox* nextGridItem()
{
ASSERT(!m_grid.isEmpty());
size_t& varyingTrackIndex = (m_direction == ForColumns) ? m_rowIndex : m_columnIndex;
const size_t endOfVaryingTrackIndex = (m_direction == ForColumns) ? m_grid.size() : m_grid[0].size();
for (; varyingTrackIndex < endOfVaryingTrackIndex; ++varyingTrackIndex) {
const GridCell& children = m_grid[m_rowIndex][m_columnIndex];
if (m_childIndex < children.size())
return children[m_childIndex++];
m_childIndex = 0;
}
return nullptr;
}
bool checkEmptyCells(size_t rowSpan, size_t columnSpan) const
{
// Ignore cells outside current grid as we will grow it later if needed.
size_t maxRows = std::min(m_rowIndex + rowSpan, m_grid.size());
size_t maxColumns = std::min(m_columnIndex + columnSpan, m_grid[0].size());
// This adds a O(N^2) behavior that shouldn't be a big deal as we expect spanning areas to be small.
for (size_t row = m_rowIndex; row < maxRows; ++row) {
for (size_t column = m_columnIndex; column < maxColumns; ++column) {
const GridCell& children = m_grid[row][column];
if (!children.isEmpty())
return false;
}
}
return true;
}
PassOwnPtr<GridCoordinate> nextEmptyGridArea(size_t fixedTrackSpan, size_t varyingTrackSpan)
{
ASSERT(!m_grid.isEmpty());
ASSERT(fixedTrackSpan >= 1 && varyingTrackSpan >= 1);
size_t rowSpan = (m_direction == ForColumns) ? varyingTrackSpan : fixedTrackSpan;
size_t columnSpan = (m_direction == ForColumns) ? fixedTrackSpan : varyingTrackSpan;
size_t& varyingTrackIndex = (m_direction == ForColumns) ? m_rowIndex : m_columnIndex;
const size_t endOfVaryingTrackIndex = (m_direction == ForColumns) ? m_grid.size() : m_grid[0].size();
for (; varyingTrackIndex < endOfVaryingTrackIndex; ++varyingTrackIndex) {
if (checkEmptyCells(rowSpan, columnSpan)) {
OwnPtr<GridCoordinate> result = adoptPtr(new GridCoordinate(GridSpan::definiteGridSpan(m_rowIndex, m_rowIndex + rowSpan), GridSpan::definiteGridSpan(m_columnIndex, m_columnIndex + columnSpan)));
// Advance the iterator to avoid an infinite loop where we would return the same grid area over and over.
++varyingTrackIndex;
return result.release();
}
}
return nullptr;
}
private:
const GridRepresentation& m_grid;
GridTrackSizingDirection m_direction;
size_t m_rowIndex;
size_t m_columnIndex;
size_t m_childIndex;
};
struct LayoutGrid::GridSizingData {
WTF_MAKE_NONCOPYABLE(GridSizingData);
STACK_ALLOCATED();
public:
GridSizingData(size_t gridColumnCount, size_t gridRowCount)
: columnTracks(gridColumnCount)
, rowTracks(gridRowCount)
{
}
Vector<GridTrack> columnTracks;
Vector<GridTrack> rowTracks;
Vector<size_t> contentSizedTracksIndex;
// Performance optimization: hold onto these Vectors until the end of Layout to avoid repeated malloc / free.
Vector<GridTrack*> filteredTracks;
Vector<GridItemWithSpan> itemsSortedByIncreasingSpan;
Vector<GridTrack*> growBeyondGrowthLimitsTracks;
LayoutUnit& freeSpaceForDirection(GridTrackSizingDirection direction) { return direction == ForColumns ? freeSpaceForColumns : freeSpaceForRows; }
private:
LayoutUnit freeSpaceForColumns { };
LayoutUnit freeSpaceForRows { };
};
struct GridItemsSpanGroupRange {
Vector<GridItemWithSpan>::iterator rangeStart;
Vector<GridItemWithSpan>::iterator rangeEnd;
};
LayoutGrid::LayoutGrid(Element* element)
: LayoutBlock(element)
, m_gridIsDirty(true)
, m_orderIterator(this)
{
ASSERT(!childrenInline());
}
LayoutGrid::~LayoutGrid()
{
}
void LayoutGrid::addChild(LayoutObject* newChild, LayoutObject* beforeChild)
{
LayoutBlock::addChild(newChild, beforeChild);
// The grid needs to be recomputed as it might contain auto-placed items that will change their position.
dirtyGrid();
}
void LayoutGrid::removeChild(LayoutObject* child)
{
LayoutBlock::removeChild(child);
// The grid needs to be recomputed as it might contain auto-placed items that will change their position.
dirtyGrid();
}
void LayoutGrid::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
{
LayoutBlock::styleDidChange(diff, oldStyle);
if (!oldStyle)
return;
// FIXME: The following checks could be narrowed down if we kept track of which type of grid items we have:
// - explicit grid size changes impact negative explicitely positioned and auto-placed grid items.
// - named grid lines only impact grid items with named grid lines.
// - auto-flow changes only impacts auto-placed children.
if (explicitGridDidResize(*oldStyle)
|| namedGridLinesDefinitionDidChange(*oldStyle)
|| oldStyle->gridAutoFlow() != styleRef().gridAutoFlow())
dirtyGrid();
}
bool LayoutGrid::explicitGridDidResize(const ComputedStyle& oldStyle) const
{
return oldStyle.gridTemplateColumns().size() != styleRef().gridTemplateColumns().size()
|| oldStyle.gridTemplateRows().size() != styleRef().gridTemplateRows().size();
}
bool LayoutGrid::namedGridLinesDefinitionDidChange(const ComputedStyle& oldStyle) const
{
return oldStyle.namedGridRowLines() != styleRef().namedGridRowLines()
|| oldStyle.namedGridColumnLines() != styleRef().namedGridColumnLines();
}
LayoutUnit LayoutGrid::computeTrackBasedLogicalHeight(const GridSizingData& sizingData) const
{
LayoutUnit logicalHeight;
for (const auto& row : sizingData.rowTracks)
logicalHeight += row.baseSize();
logicalHeight += guttersSize(ForRows, sizingData.rowTracks.size());
return logicalHeight;
}
void LayoutGrid::computeTrackSizesForDirection(GridTrackSizingDirection direction, GridSizingData& sizingData, LayoutUnit freeSpace)
{
ASSERT(freeSpace >= 0);
sizingData.freeSpaceForDirection(direction) = freeSpace - guttersSize(direction, direction == ForRows ? gridRowCount() : gridColumnCount());
LayoutUnit baseSizes, growthLimits;
computeUsedBreadthOfGridTracks(direction, sizingData, baseSizes, growthLimits, AvailableSpaceDefinite);
ASSERT(tracksAreWiderThanMinTrackBreadth(direction, sizingData));
}
void LayoutGrid::layoutBlock(bool relayoutChildren)
{
ASSERT(needsLayout());
if (!relayoutChildren && simplifiedLayout())
return;
{
// LayoutState needs this deliberate scope to pop before updating scroll information (which
// may trigger relayout).
LayoutState state(*this, locationOffset());
LayoutSize previousSize = size();
updateLogicalWidth();
bool logicalHeightWasIndefinite = computeContentLogicalHeight(MainOrPreferredSize, style()->logicalHeight(), -1) == -1;
TextAutosizer::LayoutScope textAutosizerLayoutScope(this);
placeItemsOnGrid();
GridSizingData sizingData(gridColumnCount(), gridRowCount());
// At this point the logical width is always definite as the above call to updateLogicalWidth()
// properly resolves intrinsic sizes. We cannot do the same for heights though because many code
// paths inside updateLogicalHeight() require a previous call to setLogicalHeight() to resolve
// heights properly (like for positioned items for example).
computeTrackSizesForDirection(ForColumns, sizingData, availableLogicalWidth());
if (logicalHeightWasIndefinite)
computeIntrinsicLogicalHeight(sizingData);
else
computeTrackSizesForDirection(ForRows, sizingData, availableLogicalHeight(ExcludeMarginBorderPadding));
setLogicalHeight(computeTrackBasedLogicalHeight(sizingData) + borderAndPaddingLogicalHeight());
LayoutUnit oldClientAfterEdge = clientLogicalBottom();
updateLogicalHeight();
// The above call might have changed the grid's logical height depending on min|max height restrictions.
// Update the sizes of the rows whose size depends on the logical height (also on definite|indefinite sizes).
if (logicalHeightWasIndefinite)
computeTrackSizesForDirection(ForRows, sizingData, contentLogicalHeight());
// Grid container should have the minimum height of a line if it's editable. That doesn't affect track sizing though.
if (hasLineIfEmpty())
setLogicalHeight(std::max(logicalHeight(), minimumLogicalHeightForEmptyLine()));
applyStretchAlignmentToTracksIfNeeded(ForColumns, sizingData);
applyStretchAlignmentToTracksIfNeeded(ForRows, sizingData);
layoutGridItems(sizingData);
if (size() != previousSize)
relayoutChildren = true;
layoutPositionedObjects(relayoutChildren || isDocumentElement());
computeOverflow(oldClientAfterEdge);
}
updateLayerTransformAfterLayout();
updateScrollInfoAfterLayout();
clearNeedsLayout();
}
LayoutUnit LayoutGrid::guttersSize(GridTrackSizingDirection direction, size_t span) const
{
ASSERT(span >= 1);
if (span == 1)
return 0;
const Length& trackGap = direction == ForColumns ? styleRef().gridColumnGap() : styleRef().gridRowGap();
return valueForLength(trackGap, 0) * (span - 1);
}
void LayoutGrid::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
{
const_cast<LayoutGrid*>(this)->placeItemsOnGrid();
GridSizingData sizingData(gridColumnCount(), gridRowCount());
sizingData.freeSpaceForDirection(ForColumns) = 0;
const_cast<LayoutGrid*>(this)->computeUsedBreadthOfGridTracks(ForColumns, sizingData, minLogicalWidth, maxLogicalWidth, AvailableSpaceIndefinite);
LayoutUnit totalGuttersSize = guttersSize(ForColumns, sizingData.columnTracks.size());
minLogicalWidth += totalGuttersSize;
maxLogicalWidth += totalGuttersSize;
LayoutUnit scrollbarWidth = intrinsicScrollbarLogicalWidth();
minLogicalWidth += scrollbarWidth;
maxLogicalWidth += scrollbarWidth;
}
void LayoutGrid::computeIntrinsicLogicalHeight(GridSizingData& sizingData)
{
ASSERT(tracksAreWiderThanMinTrackBreadth(ForColumns, sizingData));
sizingData.freeSpaceForDirection(ForRows) = 0;
computeUsedBreadthOfGridTracks(ForRows, sizingData, m_minContentHeight, m_maxContentHeight, AvailableSpaceIndefinite);
LayoutUnit totalGuttersSize = guttersSize(ForRows, gridRowCount());
m_minContentHeight += totalGuttersSize;
m_maxContentHeight += totalGuttersSize;
ASSERT(tracksAreWiderThanMinTrackBreadth(ForRows, sizingData));
}
LayoutUnit LayoutGrid::computeIntrinsicLogicalContentHeightUsing(const Length& logicalHeightLength, LayoutUnit intrinsicContentHeight, LayoutUnit borderAndPadding) const
{
if (logicalHeightLength.isMinContent())
return m_minContentHeight;
if (logicalHeightLength.isMaxContent())
return m_maxContentHeight;
if (logicalHeightLength.isFitContent()) {
if (m_minContentHeight == -1 || m_maxContentHeight == -1)
return -1;
LayoutUnit fillAvailableExtent = containingBlock()->availableLogicalHeight(ExcludeMarginBorderPadding);
return std::min<LayoutUnit>(m_maxContentHeight, std::max<LayoutUnit>(m_minContentHeight, fillAvailableExtent));
}
if (logicalHeightLength.isFillAvailable())
return containingBlock()->availableLogicalHeight(ExcludeMarginBorderPadding) - borderAndPadding;
ASSERT_NOT_REACHED();
return 0;
}
static inline double normalizedFlexFraction(const GridTrack& track, double flexFactor)
{
return track.baseSize() / std::max<double>(1, flexFactor);
}
void LayoutGrid::computeUsedBreadthOfGridTracks(GridTrackSizingDirection direction, GridSizingData& sizingData, LayoutUnit& baseSizesWithoutMaximization, LayoutUnit& growthLimitsWithoutMaximization, AvailableSpaceType availableSpaceType)
{
LayoutUnit& freeSpace = sizingData.freeSpaceForDirection(direction);
const LayoutUnit initialFreeSpace = freeSpace;
Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
Vector<size_t> flexibleSizedTracksIndex;
sizingData.contentSizedTracksIndex.shrink(0);
const LayoutUnit maxSize = std::max(LayoutUnit(), initialFreeSpace);
// 1. Initialize per Grid track variables.
for (size_t i = 0; i < tracks.size(); ++i) {
GridTrack& track = tracks[i];
GridTrackSize trackSize = gridTrackSize(direction, i);
const GridLength& minTrackBreadth = trackSize.minTrackBreadth();
const GridLength& maxTrackBreadth = trackSize.maxTrackBreadth();
track.setBaseSize(computeUsedBreadthOfMinLength(minTrackBreadth, maxSize));
track.setGrowthLimit(computeUsedBreadthOfMaxLength(maxTrackBreadth, track.baseSize(), maxSize));
track.setInfinitelyGrowable(false);
if (trackSize.isContentSized())
sizingData.contentSizedTracksIndex.append(i);
if (trackSize.maxTrackBreadth().isFlex())
flexibleSizedTracksIndex.append(i);
}
// 2. Resolve content-based TrackSizingFunctions.
if (!sizingData.contentSizedTracksIndex.isEmpty())
resolveContentBasedTrackSizingFunctions(direction, sizingData);
baseSizesWithoutMaximization = growthLimitsWithoutMaximization = 0;
for (const auto& track: tracks) {
ASSERT(!track.infiniteGrowthPotential());
baseSizesWithoutMaximization += track.baseSize();
growthLimitsWithoutMaximization += track.growthLimit();
}
freeSpace = initialFreeSpace - baseSizesWithoutMaximization;
bool hasDefiniteFreeSpace = availableSpaceType == AvailableSpaceDefinite;
if (hasDefiniteFreeSpace && freeSpace <= 0)
return;
// 3. Grow all Grid tracks in GridTracks from their baseSize up to their growthLimit value until freeSpace is exhausted.
const size_t tracksSize = tracks.size();
if (hasDefiniteFreeSpace) {
Vector<GridTrack*> tracksForDistribution(tracksSize);
for (size_t i = 0; i < tracksSize; ++i) {
tracksForDistribution[i] = tracks.data() + i;
tracksForDistribution[i]->setPlannedSize(tracksForDistribution[i]->baseSize());
}
distributeSpaceToTracks<MaximizeTracks>(tracksForDistribution, nullptr, sizingData, freeSpace);
for (auto* track : tracksForDistribution)
track->setBaseSize(track->plannedSize());
} else {
for (auto& track : tracks)
track.setBaseSize(track.growthLimit());
}
if (flexibleSizedTracksIndex.isEmpty())
return;
// 4. Grow all Grid tracks having a fraction as the MaxTrackSizingFunction.
double flexFraction = 0;
if (hasDefiniteFreeSpace) {
flexFraction = findFlexFactorUnitSize(tracks, GridSpan::definiteGridSpan(0, tracks.size()), direction, initialFreeSpace);
} else {
for (const auto& trackIndex : flexibleSizedTracksIndex)
flexFraction = std::max(flexFraction, normalizedFlexFraction(tracks[trackIndex], gridTrackSize(direction, trackIndex).maxTrackBreadth().flex()));
for (size_t i = 0; i < flexibleSizedTracksIndex.size(); ++i) {
GridIterator iterator(m_grid, direction, flexibleSizedTracksIndex[i]);
while (LayoutBox* gridItem = iterator.nextGridItem()) {
const GridSpan span = cachedGridSpan(*gridItem, direction);
// Do not include already processed items.
if (i > 0 && span.resolvedInitialPosition() <= flexibleSizedTracksIndex[i - 1])
continue;
flexFraction = std::max(flexFraction, findFlexFactorUnitSize(tracks, span, direction, maxContentForChild(*gridItem, direction, sizingData.columnTracks)));
}
}
}
for (const auto& trackIndex : flexibleSizedTracksIndex) {
GridTrackSize trackSize = gridTrackSize(direction, trackIndex);
LayoutUnit oldBaseSize = tracks[trackIndex].baseSize();
LayoutUnit baseSize = std::max<LayoutUnit>(oldBaseSize, flexFraction * trackSize.maxTrackBreadth().flex());
if (LayoutUnit increment = baseSize - oldBaseSize) {
tracks[trackIndex].setBaseSize(baseSize);
freeSpace -= increment;
baseSizesWithoutMaximization += increment;
growthLimitsWithoutMaximization += increment;
}
}
}
LayoutUnit LayoutGrid::computeUsedBreadthOfMinLength(const GridLength& gridLength, LayoutUnit maxSize) const
{
if (gridLength.isFlex())
return 0;
const Length& trackLength = gridLength.length();
if (trackLength.isSpecified())
return valueForLength(trackLength, maxSize);
ASSERT(trackLength.isMinContent() || trackLength.isAuto() || trackLength.isMaxContent());
return 0;
}
LayoutUnit LayoutGrid::computeUsedBreadthOfMaxLength(const GridLength& gridLength, LayoutUnit usedBreadth, LayoutUnit maxSize) const
{
if (gridLength.isFlex())
return usedBreadth;
const Length& trackLength = gridLength.length();
if (trackLength.isSpecified())
return valueForLength(trackLength, maxSize);
ASSERT(trackLength.isMinContent() || trackLength.isAuto() || trackLength.isMaxContent());
return infinity;
}
double LayoutGrid::computeFlexFactorUnitSize(const Vector<GridTrack>& tracks, GridTrackSizingDirection direction, double flexFactorSum, LayoutUnit& leftOverSpace, const Vector<size_t, 8>& flexibleTracksIndexes, PassOwnPtr<TrackIndexSet> tracksToTreatAsInflexible) const
{
// We want to avoid the effect of flex factors sum below 1 making the factor unit size to grow exponentially.
double hypotheticalFactorUnitSize = leftOverSpace / std::max<double>(1, flexFactorSum);
// product of the hypothetical "flex factor unit" and any flexible track's "flex factor" must be grater than such track's "base size".
OwnPtr<TrackIndexSet> additionalTracksToTreatAsInflexible = tracksToTreatAsInflexible;
bool validFlexFactorUnit = true;
for (auto index : flexibleTracksIndexes) {
if (additionalTracksToTreatAsInflexible && additionalTracksToTreatAsInflexible->contains(index))
continue;
LayoutUnit baseSize = tracks[index].baseSize();
double flexFactor = gridTrackSize(direction, index).maxTrackBreadth().flex();
// treating all such tracks as inflexible.
if (baseSize > hypotheticalFactorUnitSize * flexFactor) {
leftOverSpace -= baseSize;
flexFactorSum -= flexFactor;
if (!additionalTracksToTreatAsInflexible)
additionalTracksToTreatAsInflexible = adoptPtr(new TrackIndexSet());
additionalTracksToTreatAsInflexible->add(index);
validFlexFactorUnit = false;
}
}
if (!validFlexFactorUnit)
return computeFlexFactorUnitSize(tracks, direction, flexFactorSum, leftOverSpace, flexibleTracksIndexes, additionalTracksToTreatAsInflexible.release());
return hypotheticalFactorUnitSize;
}
double LayoutGrid::findFlexFactorUnitSize(const Vector<GridTrack>& tracks, const GridSpan& tracksSpan, GridTrackSizingDirection direction, LayoutUnit leftOverSpace) const
{
if (leftOverSpace <= 0)
return 0;
double flexFactorSum = 0;
Vector<size_t, 8> flexibleTracksIndexes;
for (const auto& trackIndex : tracksSpan) {
GridTrackSize trackSize = gridTrackSize(direction, trackIndex);
if (!trackSize.maxTrackBreadth().isFlex()) {
leftOverSpace -= tracks[trackIndex].baseSize();
} else {
flexibleTracksIndexes.append(trackIndex);
flexFactorSum += trackSize.maxTrackBreadth().flex();
}
}
// The function is not called if we don't have <flex> grid tracks
ASSERT(!flexibleTracksIndexes.isEmpty());
return computeFlexFactorUnitSize(tracks, direction, flexFactorSum, leftOverSpace, flexibleTracksIndexes);
}
bool LayoutGrid::hasDefiniteLogicalSize(GridTrackSizingDirection direction) const
{
return (direction == ForRows) ? hasDefiniteLogicalHeight() : hasDefiniteLogicalWidth();
}
GridTrackSize LayoutGrid::gridTrackSize(GridTrackSizingDirection direction, size_t i) const
{
bool isForColumns = direction == ForColumns;
const Vector<GridTrackSize>& trackStyles = isForColumns ? style()->gridTemplateColumns() : style()->gridTemplateRows();
const GridTrackSize& trackSize = (i >= trackStyles.size()) ? (isForColumns ? style()->gridAutoColumns() : style()->gridAutoRows()) : trackStyles[i];
GridLength minTrackBreadth = trackSize.minTrackBreadth();
GridLength maxTrackBreadth = trackSize.maxTrackBreadth();
// If the logical width/height of the grid container is indefinite, percentage values are treated as <auto>
if (minTrackBreadth.hasPercentage() || maxTrackBreadth.hasPercentage()) {
if (!hasDefiniteLogicalSize(direction)) {
if (minTrackBreadth.hasPercentage())
minTrackBreadth = Length(Auto);
if (maxTrackBreadth.hasPercentage())
maxTrackBreadth = Length(Auto);
}
}
return GridTrackSize(minTrackBreadth, maxTrackBreadth);
}
LayoutUnit LayoutGrid::logicalHeightForChild(LayoutBox& child, Vector<GridTrack>& columnTracks)
{
SubtreeLayoutScope layoutScope(child);
LayoutUnit oldOverrideContainingBlockContentLogicalWidth = child.hasOverrideContainingBlockLogicalWidth() ? child.overrideContainingBlockContentLogicalWidth() : LayoutUnit();
LayoutUnit overrideContainingBlockContentLogicalWidth = gridAreaBreadthForChild(child, ForColumns, columnTracks);
if (child.hasRelativeLogicalHeight() || oldOverrideContainingBlockContentLogicalWidth != overrideContainingBlockContentLogicalWidth) {
layoutScope.setNeedsLayout(&child, LayoutInvalidationReason::GridChanged);
}
bool hasOverrideHeight = child.hasOverrideLogicalContentHeight();
// We need to clear the stretched height to properly compute logical height during layout.
if (hasOverrideHeight && child.needsLayout())
child.clearOverrideLogicalContentHeight();
child.setOverrideContainingBlockContentLogicalWidth(overrideContainingBlockContentLogicalWidth);
// If |child| has a relative logical height, we shouldn't let it override its intrinsic height, which is
// what we are interested in here. Thus we need to set the override logical height to -1 (no possible resolution).
if (child.hasRelativeLogicalHeight())
child.setOverrideContainingBlockContentLogicalHeight(-1);
child.layoutIfNeeded();
// If the child was stretched we should use its intrinsic height.
return (hasOverrideHeight ? childIntrinsicHeight(child) : child.logicalHeight()) + child.marginLogicalHeight();
}
LayoutUnit LayoutGrid::minSizeForChild(LayoutBox& child, GridTrackSizingDirection direction, Vector<GridTrack>& columnTracks)
{
bool hasOrthogonalWritingMode = child.isHorizontalWritingMode() != isHorizontalWritingMode();
// TODO(svillar): Properly support orthogonal writing mode.
if (hasOrthogonalWritingMode)
return LayoutUnit();
const Length& childMinSize = direction == ForColumns ? child.style()->logicalMinWidth() : child.style()->logicalMinHeight();
if (childMinSize.isAuto()) {
// TODO(svillar): Implement intrinsic aspect ratio support (transferred size in specs).
return minContentForChild(child, direction, columnTracks);
}
if (direction == ForColumns)
return child.computeLogicalWidthUsing(MinSize, childMinSize, contentLogicalWidth(), this);
return child.computeContentLogicalHeight(MinSize, childMinSize, child.logicalHeight()) + child.scrollbarLogicalHeight();
}
LayoutUnit LayoutGrid::minContentForChild(LayoutBox& child, GridTrackSizingDirection direction, Vector<GridTrack>& columnTracks)
{
bool hasOrthogonalWritingMode = child.isHorizontalWritingMode() != isHorizontalWritingMode();
// FIXME: Properly support orthogonal writing mode.
if (hasOrthogonalWritingMode)
return 0;
if (direction == ForColumns) {
// If |child| has a relative logical width, we shouldn't let it override its intrinsic width, which is
// what we are interested in here. Thus we need to set the override logical width to -1 (no possible resolution).
if (child.hasRelativeLogicalWidth())
child.setOverrideContainingBlockContentLogicalWidth(-1);
// FIXME: It's unclear if we should return the intrinsic width or the preferred width.
// See http://lists.w3.org/Archives/Public/www-style/2013Jan/0245.html
return child.minPreferredLogicalWidth() + marginIntrinsicLogicalWidthForChild(child);
}
return logicalHeightForChild(child, columnTracks);
}
LayoutUnit LayoutGrid::maxContentForChild(LayoutBox& child, GridTrackSizingDirection direction, Vector<GridTrack>& columnTracks)
{
bool hasOrthogonalWritingMode = child.isHorizontalWritingMode() != isHorizontalWritingMode();
// FIXME: Properly support orthogonal writing mode.
if (hasOrthogonalWritingMode)
return LayoutUnit();
if (direction == ForColumns) {
// If |child| has a relative logical width, we shouldn't let it override its intrinsic width, which is
// what we are interested in here. Thus we need to set the override logical width to -1 (no possible resolution).
if (child.hasRelativeLogicalWidth())
child.setOverrideContainingBlockContentLogicalWidth(-1);
// FIXME: It's unclear if we should return the intrinsic width or the preferred width.
// See http://lists.w3.org/Archives/Public/www-style/2013Jan/0245.html
return child.maxPreferredLogicalWidth() + marginIntrinsicLogicalWidthForChild(child);
}
return logicalHeightForChild(child, columnTracks);
}
// We're basically using a class instead of a std::pair because of accessing gridItem() or gridSpan() is much more
// self-explanatory that using .first or .second members in the pair. Having a std::pair<LayoutBox*, size_t>
// does not work either because we still need the GridSpan so we'd have to add an extra hash lookup for each item
// at the beginning of LayoutGrid::resolveContentBasedTrackSizingFunctionsForItems().
class GridItemWithSpan {
public:
GridItemWithSpan(LayoutBox& gridItem, const GridSpan& gridSpan)
: m_gridItem(&gridItem)
, m_gridSpan(gridSpan)
{
}
LayoutBox& gridItem() const { return *m_gridItem; }
GridSpan gridSpan() const { return m_gridSpan; }
bool operator<(const GridItemWithSpan other) const { return m_gridSpan.integerSpan() < other.m_gridSpan.integerSpan(); }
private:
LayoutBox* m_gridItem;
GridSpan m_gridSpan;
};
bool LayoutGrid::spanningItemCrossesFlexibleSizedTracks(const GridSpan& span, GridTrackSizingDirection direction) const
{
for (const auto& trackPosition : span) {
const GridTrackSize& trackSize = gridTrackSize(direction, trackPosition);
if (trackSize.minTrackBreadth().isFlex() || trackSize.maxTrackBreadth().isFlex())
return true;
}
return false;
}
void LayoutGrid::resolveContentBasedTrackSizingFunctions(GridTrackSizingDirection direction, GridSizingData& sizingData)
{
sizingData.itemsSortedByIncreasingSpan.shrink(0);
HashSet<LayoutBox*> itemsSet;
for (const auto& trackIndex : sizingData.contentSizedTracksIndex) {
GridIterator iterator(m_grid, direction, trackIndex);
GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackIndex] : sizingData.rowTracks[trackIndex];
while (LayoutBox* gridItem = iterator.nextGridItem()) {
if (itemsSet.add(gridItem).isNewEntry) {
const GridSpan& span = cachedGridSpan(*gridItem, direction);
if (span.integerSpan() == 1) {
resolveContentBasedTrackSizingFunctionsForNonSpanningItems(direction, span, *gridItem, track, sizingData.columnTracks);
} else if (!spanningItemCrossesFlexibleSizedTracks(span, direction)) {
sizingData.itemsSortedByIncreasingSpan.append(GridItemWithSpan(*gridItem, span));
}
}
}
}
std::sort(sizingData.itemsSortedByIncreasingSpan.begin(), sizingData.itemsSortedByIncreasingSpan.end());
auto it = sizingData.itemsSortedByIncreasingSpan.begin();
auto end = sizingData.itemsSortedByIncreasingSpan.end();
while (it != end) {
GridItemsSpanGroupRange spanGroupRange = { it, std::upper_bound(it, end, *it) };
resolveContentBasedTrackSizingFunctionsForItems<ResolveIntrinsicMinimums>(direction, sizingData, spanGroupRange);
resolveContentBasedTrackSizingFunctionsForItems<ResolveContentBasedMinimums>(direction, sizingData, spanGroupRange);
resolveContentBasedTrackSizingFunctionsForItems<ResolveMaxContentMinimums>(direction, sizingData, spanGroupRange);
resolveContentBasedTrackSizingFunctionsForItems<ResolveIntrinsicMaximums>(direction, sizingData, spanGroupRange);
resolveContentBasedTrackSizingFunctionsForItems<ResolveMaxContentMaximums>(direction, sizingData, spanGroupRange);
it = spanGroupRange.rangeEnd;
}
for (const auto& trackIndex : sizingData.contentSizedTracksIndex) {
GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackIndex] : sizingData.rowTracks[trackIndex];
if (track.growthLimitIsInfinite())
track.setGrowthLimit(track.baseSize());
}
}
void LayoutGrid::resolveContentBasedTrackSizingFunctionsForNonSpanningItems(GridTrackSizingDirection direction, const GridSpan& span, LayoutBox& gridItem, GridTrack& track, Vector<GridTrack>& columnTracks)
{
const size_t trackPosition = span.resolvedInitialPosition();
GridTrackSize trackSize = gridTrackSize(direction, trackPosition);
if (trackSize.hasMinContentMinTrackBreadth())
track.setBaseSize(std::max(track.baseSize(), minContentForChild(gridItem, direction, columnTracks)));
else if (trackSize.hasMaxContentMinTrackBreadth())
track.setBaseSize(std::max(track.baseSize(), maxContentForChild(gridItem, direction, columnTracks)));
else if (trackSize.hasAutoMinTrackBreadth())
track.setBaseSize(std::max(track.baseSize(), minSizeForChild(gridItem, direction, columnTracks)));
if (trackSize.hasMinContentMaxTrackBreadth())
track.setGrowthLimit(std::max(track.growthLimit(), minContentForChild(gridItem, direction, columnTracks)));
else if (trackSize.hasMaxContentOrAutoMaxTrackBreadth())
track.setGrowthLimit(std::max(track.growthLimit(), maxContentForChild(gridItem, direction, columnTracks)));
}
static const LayoutUnit& trackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase phase, const GridTrack& track, TrackSizeRestriction restriction)
{
switch (phase) {
case ResolveIntrinsicMinimums:
case ResolveContentBasedMinimums:
case ResolveMaxContentMinimums:
case MaximizeTracks:
return track.baseSize();
case ResolveIntrinsicMaximums:
case ResolveMaxContentMaximums:
const LayoutUnit& growthLimit = track.growthLimit();
if (restriction == AllowInfinity)
return growthLimit;
return growthLimit == infinity ? track.baseSize() : growthLimit;
}
ASSERT_NOT_REACHED();
return track.baseSize();
}
static bool shouldProcessTrackForTrackSizeComputationPhase(TrackSizeComputationPhase phase, const GridTrackSize& trackSize)
{
switch (phase) {
case ResolveIntrinsicMinimums:
return trackSize.hasIntrinsicMinTrackBreadth();
case ResolveContentBasedMinimums:
return trackSize.hasMinOrMaxContentMinTrackBreadth();
case ResolveMaxContentMinimums:
return trackSize.hasMaxContentMinTrackBreadth();
case ResolveIntrinsicMaximums:
return trackSize.hasMinOrMaxContentMaxTrackBreadth();
case ResolveMaxContentMaximums:
return trackSize.hasMaxContentOrAutoMaxTrackBreadth();
case MaximizeTracks:
ASSERT_NOT_REACHED();
return false;
}
ASSERT_NOT_REACHED();
return false;
}
static bool trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(TrackSizeComputationPhase phase, const GridTrackSize& trackSize)
{
switch (phase) {
case ResolveIntrinsicMinimums:
case ResolveContentBasedMinimums:
return trackSize.hasAutoOrMinContentMinTrackBreadthAndIntrinsicMaxTrackBreadth();
case ResolveMaxContentMinimums:
return trackSize.hasMaxContentMinTrackBreadthAndMaxContentMaxTrackBreadth();
case ResolveIntrinsicMaximums:
case ResolveMaxContentMaximums:
return true;
case MaximizeTracks:
ASSERT_NOT_REACHED();
return false;
}
ASSERT_NOT_REACHED();
return false;
}
static void markAsInfinitelyGrowableForTrackSizeComputationPhase(TrackSizeComputationPhase phase, GridTrack& track)
{
switch (phase) {
case ResolveIntrinsicMinimums:
case ResolveContentBasedMinimums:
case ResolveMaxContentMinimums:
return;
case ResolveIntrinsicMaximums:
if (trackSizeForTrackSizeComputationPhase(phase, track, AllowInfinity) == infinity && track.plannedSize() != infinity)
track.setInfinitelyGrowable(true);
return;
case ResolveMaxContentMaximums:
if (track.infinitelyGrowable())
track.setInfinitelyGrowable(false);
return;
case MaximizeTracks:
ASSERT_NOT_REACHED();
return;
}
ASSERT_NOT_REACHED();
}
static void updateTrackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase phase, GridTrack& track)
{
switch (phase) {
case ResolveIntrinsicMinimums:
case ResolveContentBasedMinimums:
case ResolveMaxContentMinimums:
track.setBaseSize(track.plannedSize());
return;
case ResolveIntrinsicMaximums:
case ResolveMaxContentMaximums:
track.setGrowthLimit(track.plannedSize());
return;
case MaximizeTracks:
ASSERT_NOT_REACHED();
return;
}
ASSERT_NOT_REACHED();
}
LayoutUnit LayoutGrid::currentItemSizeForTrackSizeComputationPhase(TrackSizeComputationPhase phase, LayoutBox& gridItem, GridTrackSizingDirection direction, Vector<GridTrack>& columnTracks)
{
switch (phase) {
case ResolveIntrinsicMinimums:
return minSizeForChild(gridItem, direction, columnTracks);
case ResolveContentBasedMinimums:
case ResolveIntrinsicMaximums:
return minContentForChild(gridItem, direction, columnTracks);
case ResolveMaxContentMinimums:
case ResolveMaxContentMaximums:
return maxContentForChild(gridItem, direction, columnTracks);
case MaximizeTracks:
ASSERT_NOT_REACHED();
return 0;
}
ASSERT_NOT_REACHED();
return 0;
}
template <TrackSizeComputationPhase phase>
void LayoutGrid::resolveContentBasedTrackSizingFunctionsForItems(GridTrackSizingDirection direction, GridSizingData& sizingData, const GridItemsSpanGroupRange& gridItemsWithSpan)
{
Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
for (const auto& trackIndex : sizingData.contentSizedTracksIndex) {
GridTrack& track = tracks[trackIndex];
track.setPlannedSize(trackSizeForTrackSizeComputationPhase(phase, track, AllowInfinity));
}
for (auto it = gridItemsWithSpan.rangeStart; it != gridItemsWithSpan.rangeEnd; ++it) {
GridItemWithSpan& gridItemWithSpan = *it;
ASSERT(gridItemWithSpan.gridSpan().integerSpan() > 1);
const GridSpan& itemSpan = gridItemWithSpan.gridSpan();
sizingData.growBeyondGrowthLimitsTracks.shrink(0);
sizingData.filteredTracks.shrink(0);
LayoutUnit spanningTracksSize;
for (const auto& trackPosition : itemSpan) {
GridTrackSize trackSize = gridTrackSize(direction, trackPosition);
GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackPosition] : sizingData.rowTracks[trackPosition];
spanningTracksSize += trackSizeForTrackSizeComputationPhase(phase, track, ForbidInfinity);
if (!shouldProcessTrackForTrackSizeComputationPhase(phase, trackSize))
continue;
sizingData.filteredTracks.append(&track);
if (trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(phase, trackSize))
sizingData.growBeyondGrowthLimitsTracks.append(&track);
}
if (sizingData.filteredTracks.isEmpty())
continue;
spanningTracksSize += guttersSize(direction, itemSpan.integerSpan());
LayoutUnit extraSpace = currentItemSizeForTrackSizeComputationPhase(phase, gridItemWithSpan.gridItem(), direction, sizingData.columnTracks) - spanningTracksSize;
extraSpace = std::max<LayoutUnit>(extraSpace, 0);
auto& tracksToGrowBeyondGrowthLimits = sizingData.growBeyondGrowthLimitsTracks.isEmpty() ? sizingData.filteredTracks : sizingData.growBeyondGrowthLimitsTracks;
distributeSpaceToTracks<phase>(sizingData.filteredTracks, &tracksToGrowBeyondGrowthLimits, sizingData, extraSpace);
}
for (const auto& trackIndex : sizingData.contentSizedTracksIndex) {
GridTrack& track = tracks[trackIndex];
markAsInfinitelyGrowableForTrackSizeComputationPhase(phase, track);
updateTrackSizeForTrackSizeComputationPhase(phase, track);
}
}
static bool sortByGridTrackGrowthPotential(const GridTrack* track1, const GridTrack* track2)
{
// This check ensures that we respect the irreflexivity property of the strict weak ordering required by std::sort
// (forall x: NOT x < x).
if (track1->infiniteGrowthPotential() && track2->infiniteGrowthPotential())
return false;
if (track1->infiniteGrowthPotential() || track2->infiniteGrowthPotential())
return track2->infiniteGrowthPotential();
return (track1->growthLimit() - track1->baseSize()) < (track2->growthLimit() - track2->baseSize());
}
template <TrackSizeComputationPhase phase>
void LayoutGrid::distributeSpaceToTracks(Vector<GridTrack*>& tracks, const Vector<GridTrack*>* growBeyondGrowthLimitsTracks, GridSizingData& sizingData, LayoutUnit& availableLogicalSpace)
{
ASSERT(availableLogicalSpace >= 0);
for (auto* track : tracks)
track->setSizeDuringDistribution(trackSizeForTrackSizeComputationPhase(phase, *track, ForbidInfinity));
if (availableLogicalSpace > 0) {
std::sort(tracks.begin(), tracks.end(), sortByGridTrackGrowthPotential);
size_t tracksSize = tracks.size();
for (size_t i = 0; i < tracksSize; ++i) {
GridTrack& track = *tracks[i];
LayoutUnit availableLogicalSpaceShare = availableLogicalSpace / (tracksSize - i);
const LayoutUnit& trackBreadth = trackSizeForTrackSizeComputationPhase(phase, track, ForbidInfinity);
LayoutUnit growthShare = track.infiniteGrowthPotential() ? availableLogicalSpaceShare : std::min(availableLogicalSpaceShare, track.growthLimit() - trackBreadth);
ASSERT_WITH_MESSAGE(growthShare >= 0, "We must never shrink any grid track or else we can't guarantee we abide by our min-sizing function.");
track.growSizeDuringDistribution(growthShare);
availableLogicalSpace -= growthShare;
}
}
if (availableLogicalSpace > 0 && growBeyondGrowthLimitsTracks) {
size_t tracksGrowingAboveMaxBreadthSize = growBeyondGrowthLimitsTracks->size();
for (size_t i = 0; i < tracksGrowingAboveMaxBreadthSize; ++i) {
GridTrack* track = growBeyondGrowthLimitsTracks->at(i);
LayoutUnit growthShare = availableLogicalSpace / (tracksGrowingAboveMaxBreadthSize - i);
track->growSizeDuringDistribution(growthShare);
availableLogicalSpace -= growthShare;
}
}
for (auto* track : tracks)
track->setPlannedSize(track->plannedSize() == infinity ? track->sizeDuringDistribution() : std::max(track->plannedSize(), track->sizeDuringDistribution()));
}
#if ENABLE(ASSERT)
bool LayoutGrid::tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection direction, GridSizingData& sizingData)
{
const Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
LayoutUnit& maxSize = sizingData.freeSpaceForDirection(direction);
for (size_t i = 0; i < tracks.size(); ++i) {
GridTrackSize trackSize = gridTrackSize(direction, i);
const GridLength& minTrackBreadth = trackSize.minTrackBreadth();
if (computeUsedBreadthOfMinLength(minTrackBreadth, maxSize) > tracks[i].baseSize())
return false;
}
return true;
}
#endif
void LayoutGrid::ensureGridSize(size_t maximumRowSize, size_t maximumColumnSize)
{
const size_t oldRowSize = gridRowCount();
if (maximumRowSize > oldRowSize) {
m_grid.grow(maximumRowSize);
for (size_t row = oldRowSize; row < gridRowCount(); ++row)
m_grid[row].grow(gridColumnCount());
}
if (maximumColumnSize > gridColumnCount()) {
for (size_t row = 0; row < gridRowCount(); ++row)
m_grid[row].grow(maximumColumnSize);
}
}
void LayoutGrid::insertItemIntoGrid(LayoutBox& child, const GridCoordinate& coordinate)
{
RELEASE_ASSERT(coordinate.rows.isDefinite() && coordinate.columns.isDefinite());
ensureGridSize(coordinate.rows.resolvedFinalPosition(), coordinate.columns.resolvedFinalPosition());
for (const auto& row : coordinate.rows) {
for (const auto& column: coordinate.columns)
m_grid[row][column].append(&child);
}
}
void LayoutGrid::placeItemsOnGrid()
{
if (!m_gridIsDirty)
return;
ASSERT(m_gridItemCoordinate.isEmpty());
populateExplicitGridAndOrderIterator();
// We clear the dirty bit here as the grid sizes have been updated.
m_gridIsDirty = false;
Vector<LayoutBox*> autoMajorAxisAutoGridItems;
Vector<LayoutBox*> specifiedMajorAxisAutoGridItems;
for (LayoutBox* child = m_orderIterator.first(); child; child = m_orderIterator.next()) {
if (child->isOutOfFlowPositioned())
continue;
GridCoordinate coordinate = cachedGridCoordinate(*child);
if (!coordinate.rows.isDefinite() || !coordinate.columns.isDefinite()) {
GridSpan majorAxisPositions = (autoPlacementMajorAxisDirection() == ForColumns) ? coordinate.columns : coordinate.rows;
if (!majorAxisPositions.isDefinite())
autoMajorAxisAutoGridItems.append(child);
else
specifiedMajorAxisAutoGridItems.append(child);
continue;
}
insertItemIntoGrid(*child, coordinate);
}
ASSERT(gridRowCount() >= GridResolvedPosition::explicitGridRowCount(*style()));
ASSERT(gridColumnCount() >= GridResolvedPosition::explicitGridColumnCount(*style()));
placeSpecifiedMajorAxisItemsOnGrid(specifiedMajorAxisAutoGridItems);
placeAutoMajorAxisItemsOnGrid(autoMajorAxisAutoGridItems);
m_grid.shrinkToFit();
#if ENABLE(ASSERT)
for (LayoutBox* child = m_orderIterator.first(); child; child = m_orderIterator.next()) {
if (child->isOutOfFlowPositioned())
continue;
GridCoordinate coordinate = cachedGridCoordinate(*child);
ASSERT(coordinate.rows.isDefinite() && coordinate.columns.isDefinite());
}
#endif
}
void LayoutGrid::populateExplicitGridAndOrderIterator()
{
OrderIteratorPopulator populator(m_orderIterator);
size_t maximumRowIndex = std::max<size_t>(1, GridResolvedPosition::explicitGridRowCount(*style()));
size_t maximumColumnIndex = std::max<size_t>(1, GridResolvedPosition::explicitGridColumnCount(*style()));
ASSERT(m_gridItemsIndexesMap.isEmpty());
size_t childIndex = 0;
for (LayoutBox* child = firstChildBox(); child; child = child->nextInFlowSiblingBox()) {
if (child->isOutOfFlowPositioned())
continue;
populator.collectChild(child);
m_gridItemsIndexesMap.set(child, childIndex++);
// This function bypasses the cache (cachedGridCoordinate()) as it is used to build it.
GridSpan rowPositions = GridResolvedPosition::resolveGridPositionsFromStyle(*style(), *child, ForRows);
GridSpan columnPositions = GridResolvedPosition::resolveGridPositionsFromStyle(*style(), *child, ForColumns);
m_gridItemCoordinate.set(child, GridCoordinate(rowPositions, columnPositions));
// |positions| is 0 if we need to run the auto-placement algorithm.
if (rowPositions.isDefinite()) {
maximumRowIndex = std::max<size_t>(maximumRowIndex, rowPositions.resolvedFinalPosition());
} else {
// Grow the grid for items with a definite row span, getting the largest such span.
size_t spanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), *child, ForRows);
maximumRowIndex = std::max<size_t>(maximumRowIndex, spanSize);
}
if (columnPositions.isDefinite()) {
maximumColumnIndex = std::max<size_t>(maximumColumnIndex, columnPositions.resolvedFinalPosition());
} else {
// Grow the grid for items with a definite column span, getting the largest such span.
size_t spanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), *child, ForColumns);
maximumColumnIndex = std::max<size_t>(maximumColumnIndex, spanSize);
}
}
m_grid.grow(maximumRowIndex);
for (auto& column : m_grid)
column.grow(maximumColumnIndex);
}
PassOwnPtr<GridCoordinate> LayoutGrid::createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(const LayoutBox& gridItem, GridTrackSizingDirection specifiedDirection, const GridSpan& specifiedPositions) const
{
GridTrackSizingDirection crossDirection = specifiedDirection == ForColumns ? ForRows : ForColumns;
const size_t endOfCrossDirection = crossDirection == ForColumns ? gridColumnCount() : gridRowCount();
size_t crossDirectionSpanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), gridItem, crossDirection);
GridSpan crossDirectionPositions = GridSpan::definiteGridSpan(endOfCrossDirection, endOfCrossDirection + crossDirectionSpanSize);
return adoptPtr(new GridCoordinate(specifiedDirection == ForColumns ? crossDirectionPositions : specifiedPositions, specifiedDirection == ForColumns ? specifiedPositions : crossDirectionPositions));
}
void LayoutGrid::placeSpecifiedMajorAxisItemsOnGrid(const Vector<LayoutBox*>& autoGridItems)
{
bool isForColumns = autoPlacementMajorAxisDirection() == ForColumns;
bool isGridAutoFlowDense = style()->isGridAutoFlowAlgorithmDense();
// Mapping between the major axis tracks (rows or columns) and the last auto-placed item's position inserted on
// that track. This is needed to implement "sparse" packing for items locked to a given track.
// See http://dev.w3.org/csswg/css-grid/#auto-placement-algo
HashMap<unsigned, unsigned, DefaultHash<unsigned>::Hash, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> minorAxisCursors;
for (const auto& autoGridItem : autoGridItems) {
GridSpan majorAxisPositions = cachedGridSpan(*autoGridItem, autoPlacementMajorAxisDirection());
ASSERT(majorAxisPositions.isDefinite());
ASSERT(!cachedGridSpan(*autoGridItem, autoPlacementMinorAxisDirection()).isDefinite());
size_t minorAxisSpanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), *autoGridItem, autoPlacementMinorAxisDirection());
unsigned majorAxisInitialPosition = majorAxisPositions.resolvedInitialPosition();
GridIterator iterator(m_grid, autoPlacementMajorAxisDirection(), majorAxisPositions.resolvedInitialPosition(), isGridAutoFlowDense ? 0 : minorAxisCursors.get(majorAxisInitialPosition));
OwnPtr<GridCoordinate> emptyGridArea = iterator.nextEmptyGridArea(majorAxisPositions.integerSpan(), minorAxisSpanSize);
if (!emptyGridArea)
emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(*autoGridItem, autoPlacementMajorAxisDirection(), majorAxisPositions);
m_gridItemCoordinate.set(autoGridItem, *emptyGridArea);
insertItemIntoGrid(*autoGridItem, *emptyGridArea);
if (!isGridAutoFlowDense)
minorAxisCursors.set(majorAxisInitialPosition, isForColumns ? emptyGridArea->rows.resolvedInitialPosition() : emptyGridArea->columns.resolvedInitialPosition());
}
}
void LayoutGrid::placeAutoMajorAxisItemsOnGrid(const Vector<LayoutBox*>& autoGridItems)
{
std::pair<size_t, size_t> autoPlacementCursor = std::make_pair(0, 0);
bool isGridAutoFlowDense = style()->isGridAutoFlowAlgorithmDense();
for (const auto& autoGridItem : autoGridItems) {
placeAutoMajorAxisItemOnGrid(*autoGridItem, autoPlacementCursor);
// If grid-auto-flow is dense, reset auto-placement cursor.
if (isGridAutoFlowDense) {
autoPlacementCursor.first = 0;
autoPlacementCursor.second = 0;
}
}
}
void LayoutGrid::placeAutoMajorAxisItemOnGrid(LayoutBox& gridItem, std::pair<size_t, size_t>& autoPlacementCursor)
{
GridSpan minorAxisPositions = cachedGridSpan(gridItem, autoPlacementMinorAxisDirection());
ASSERT(!cachedGridSpan(gridItem, autoPlacementMajorAxisDirection()).isDefinite());
size_t majorAxisSpanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), gridItem, autoPlacementMajorAxisDirection());
const size_t endOfMajorAxis = (autoPlacementMajorAxisDirection() == ForColumns) ? gridColumnCount() : gridRowCount();
size_t majorAxisAutoPlacementCursor = autoPlacementMajorAxisDirection() == ForColumns ? autoPlacementCursor.second : autoPlacementCursor.first;
size_t minorAxisAutoPlacementCursor = autoPlacementMajorAxisDirection() == ForColumns ? autoPlacementCursor.first : autoPlacementCursor.second;
OwnPtr<GridCoordinate> emptyGridArea;
if (minorAxisPositions.isDefinite()) {
// Move to the next track in major axis if initial position in minor axis is before auto-placement cursor.
if (minorAxisPositions.resolvedInitialPosition() < minorAxisAutoPlacementCursor)
majorAxisAutoPlacementCursor++;
if (majorAxisAutoPlacementCursor < endOfMajorAxis) {
GridIterator iterator(m_grid, autoPlacementMinorAxisDirection(), minorAxisPositions.resolvedInitialPosition(), majorAxisAutoPlacementCursor);
emptyGridArea = iterator.nextEmptyGridArea(minorAxisPositions.integerSpan(), majorAxisSpanSize);
}
if (!emptyGridArea)
emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(gridItem, autoPlacementMinorAxisDirection(), minorAxisPositions);
} else {
size_t minorAxisSpanSize = GridResolvedPosition::spanSizeForAutoPlacedItem(*style(), gridItem, autoPlacementMinorAxisDirection());
for (size_t majorAxisIndex = majorAxisAutoPlacementCursor; majorAxisIndex < endOfMajorAxis; ++majorAxisIndex) {
GridIterator iterator(m_grid, autoPlacementMajorAxisDirection(), majorAxisIndex, minorAxisAutoPlacementCursor);
emptyGridArea = iterator.nextEmptyGridArea(majorAxisSpanSize, minorAxisSpanSize);
if (emptyGridArea) {
// Check that it fits in the minor axis direction, as we shouldn't grow in that direction here (it was already managed in populateExplicitGridAndOrderIterator()).
size_t minorAxisFinalPositionIndex = autoPlacementMinorAxisDirection() == ForColumns ? emptyGridArea->columns.resolvedFinalPosition() : emptyGridArea->rows.resolvedFinalPosition();
const size_t endOfMinorAxis = autoPlacementMinorAxisDirection() == ForColumns ? gridColumnCount() : gridRowCount();
if (minorAxisFinalPositionIndex <= endOfMinorAxis)
break;
// Discard empty grid area as it does not fit in the minor axis direction.
// We don't need to create a new empty grid area yet as we might find a valid one in the next iteration.
emptyGridArea = nullptr;
}
// As we're moving to the next track in the major axis we should reset the auto-placement cursor in the minor axis.
minorAxisAutoPlacementCursor = 0;
}
if (!emptyGridArea)
emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(gridItem, autoPlacementMinorAxisDirection(), GridSpan::definiteGridSpan(0, minorAxisSpanSize));
}
m_gridItemCoordinate.set(&gridItem, *emptyGridArea);
insertItemIntoGrid(gridItem, *emptyGridArea);
// Move auto-placement cursor to the new position.
autoPlacementCursor.first = emptyGridArea->rows.resolvedInitialPosition();
autoPlacementCursor.second = emptyGridArea->columns.resolvedInitialPosition();
}
GridTrackSizingDirection LayoutGrid::autoPlacementMajorAxisDirection() const
{
return style()->isGridAutoFlowDirectionColumn() ? ForColumns : ForRows;
}
GridTrackSizingDirection LayoutGrid::autoPlacementMinorAxisDirection() const
{
return style()->isGridAutoFlowDirectionColumn() ? ForRows : ForColumns;
}
void LayoutGrid::dirtyGrid()
{
if (m_gridIsDirty)
return;
// Even if this could be redundant, it could be seen as a defensive strategy against
// style changes events happening during the layout phase or even while the painting process
// is still ongoing.
// Forcing a new layout for the Grid layout would cancel any ongoing painting and ensure
// the grid and its children are correctly laid out according to the new style rules.
setNeedsLayout(LayoutInvalidationReason::GridChanged);
m_grid.resize(0);
m_gridItemCoordinate.clear();
m_gridItemsOverflowingGridArea.resize(0);
m_gridItemsIndexesMap.clear();
m_gridIsDirty = true;
}
void LayoutGrid::applyStretchAlignmentToTracksIfNeeded(GridTrackSizingDirection direction, GridSizingData& sizingData)
{
LayoutUnit& availableSpace = sizingData.freeSpaceForDirection(direction);
if (availableSpace <= 0
|| (direction == ForColumns && styleRef().justifyContentDistribution() != ContentDistributionStretch)
|| (direction == ForRows && styleRef().alignContentDistribution() != ContentDistributionStretch))
return;
// Spec defines auto-sized tracks as the ones with an 'auto' max-sizing function.
Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
Vector<unsigned> autoSizedTracksIndex;
for (unsigned i = 0; i < tracks.size(); ++i) {
const GridTrackSize& trackSize = gridTrackSize(direction, i);
// If there is some flexible-sized track, they should have exhausted available space during sizing algorithm.
ASSERT(!trackSize.maxTrackBreadth().isFlex());
if (trackSize.hasAutoMaxTrackBreadth())
autoSizedTracksIndex.append(i);
}
unsigned numberOfAutoSizedTracks = autoSizedTracksIndex.size();
if (numberOfAutoSizedTracks < 1)
return;
LayoutUnit sizeToIncrease = availableSpace / numberOfAutoSizedTracks;
for (const auto& trackIndex : autoSizedTracksIndex) {
GridTrack* track = tracks.data() + trackIndex;
LayoutUnit baseSize = track->baseSize() + sizeToIncrease;
track->setBaseSize(baseSize);
}
availableSpace = 0;
}
void LayoutGrid::layoutGridItems(GridSizingData& sizingData)
{
populateGridPositions(sizingData);
m_gridItemsOverflowingGridArea.resize(0);
for (LayoutBox* child = firstChildBox(); child; child = child->nextSiblingBox()) {
if (child->isOutOfFlowPositioned()) {
prepareChildForPositionedLayout(*child);
continue;
}
// Because the grid area cannot be styled, we don't need to adjust
// the grid breadth to account for 'box-sizing'.
LayoutUnit oldOverrideContainingBlockContentLogicalWidth = child->hasOverrideContainingBlockLogicalWidth() ? child->overrideContainingBlockContentLogicalWidth() : LayoutUnit();
LayoutUnit oldOverrideContainingBlockContentLogicalHeight = child->hasOverrideContainingBlockLogicalHeight() ? child->overrideContainingBlockContentLogicalHeight() : LayoutUnit();
LayoutUnit overrideContainingBlockContentLogicalWidth = gridAreaBreadthForChildIncludingAlignmentOffsets(*child, ForColumns, sizingData);
LayoutUnit overrideContainingBlockContentLogicalHeight = gridAreaBreadthForChildIncludingAlignmentOffsets(*child, ForRows, sizingData);
SubtreeLayoutScope layoutScope(*child);
if (oldOverrideContainingBlockContentLogicalWidth != overrideContainingBlockContentLogicalWidth || (oldOverrideContainingBlockContentLogicalHeight != overrideContainingBlockContentLogicalHeight && child->hasRelativeLogicalHeight()))
layoutScope.setNeedsLayout(child, LayoutInvalidationReason::GridChanged);
child->setOverrideContainingBlockContentLogicalWidth(overrideContainingBlockContentLogicalWidth);
child->setOverrideContainingBlockContentLogicalHeight(overrideContainingBlockContentLogicalHeight);
// Stretching logic might force a child layout, so we need to run it before the layoutIfNeeded
// call to avoid unnecessary relayouts. This might imply that child margins, needed to correctly
// determine the available space before stretching, are not set yet.
applyStretchAlignmentToChildIfNeeded(*child);
child->layoutIfNeeded();
// We need pending layouts to be done in order to compute auto-margins properly.
updateAutoMarginsInColumnAxisIfNeeded(*child);
updateAutoMarginsInRowAxisIfNeeded(*child);
#if ENABLE(ASSERT)
const GridCoordinate& coordinate = cachedGridCoordinate(*child);
ASSERT(coordinate.columns.resolvedInitialPosition() < sizingData.columnTracks.size());
ASSERT(coordinate.rows.resolvedInitialPosition() < sizingData.rowTracks.size());
#endif
child->setLogicalLocation(findChildLogicalPosition(*child, sizingData));
// Keep track of children overflowing their grid area as we might need to paint them even if the grid-area is
// not visible
if (child->logicalHeight() > overrideContainingBlockContentLogicalHeight
|| child->logicalWidth() > overrideContainingBlockContentLogicalWidth)
m_gridItemsOverflowingGridArea.append(child);
}
}
void LayoutGrid::prepareChildForPositionedLayout(LayoutBox& child)
{
ASSERT(child.isOutOfFlowPositioned());
child.containingBlock()->insertPositionedObject(&child);
PaintLayer* childLayer = child.layer();
childLayer->setStaticInlinePosition(borderAndPaddingStart());
childLayer->setStaticBlockPosition(borderAndPaddingBefore());
}
void LayoutGrid::layoutPositionedObjects(bool relayoutChildren, PositionedLayoutBehavior info)
{
TrackedLayoutBoxListHashSet* positionedDescendants = positionedObjects();
if (!positionedDescendants)
return;
bool containerHasHorizontalWritingMode = isHorizontalWritingMode();
for (auto* child : *positionedDescendants) {
bool hasOrthogonalWritingMode = child->isHorizontalWritingMode() != containerHasHorizontalWritingMode;
if (hasOrthogonalWritingMode) {
// FIXME: Properly support orthogonal writing mode.
continue;
}
LayoutUnit columnOffset = LayoutUnit();
LayoutUnit columnBreadth = LayoutUnit();
offsetAndBreadthForPositionedChild(*child, ForColumns, columnOffset, columnBreadth);
LayoutUnit rowOffset = LayoutUnit();
LayoutUnit rowBreadth = LayoutUnit();
offsetAndBreadthForPositionedChild(*child, ForRows, rowOffset, rowBreadth);
child->setOverrideContainingBlockContentLogicalWidth(columnBreadth);
child->setOverrideContainingBlockContentLogicalHeight(rowBreadth);
child->setExtraInlineOffset(columnOffset);
child->setExtraBlockOffset(rowOffset);
}
LayoutBlock::layoutPositionedObjects(relayoutChildren, info);
}
void LayoutGrid::offsetAndBreadthForPositionedChild(const LayoutBox& child, GridTrackSizingDirection direction, LayoutUnit& offset, LayoutUnit& breadth)
{
ASSERT(child.isHorizontalWritingMode() == isHorizontalWritingMode());
GridSpan positions = GridResolvedPosition::resolveGridPositionsFromStyle(*style(), child, direction);
if (!positions.isDefinite()) {
offset = LayoutUnit();
breadth = (direction == ForColumns) ? clientLogicalWidth() : clientLogicalHeight();
return;
}
GridPosition startPosition = (direction == ForColumns) ? child.style()->gridColumnStart() : child.style()->gridRowStart();
GridPosition endPosition = (direction == ForColumns) ? child.style()->gridColumnEnd() : child.style()->gridRowEnd();
size_t lastTrackIndex = (direction == ForColumns ? gridColumnCount() : gridRowCount()) - 1;
bool startIsAuto = startPosition.isAuto()
|| (startPosition.isNamedGridArea() && !GridResolvedPosition::isValidNamedLineOrArea(startPosition.namedGridLine(), styleRef(), GridResolvedPosition::initialPositionSide(direction)))
|| (positions.resolvedInitialPosition() > lastTrackIndex);
bool endIsAuto = endPosition.isAuto()
|| (endPosition.isNamedGridArea() && !GridResolvedPosition::isValidNamedLineOrArea(endPosition.namedGridLine(), styleRef(), GridResolvedPosition::finalPositionSide(direction)))
|| (positions.resolvedFinalPosition() - 1 > lastTrackIndex);
size_t firstPosition = 0;
size_t initialPosition = startIsAuto ? firstPosition : positions.resolvedInitialPosition();
size_t lastPosition = lastTrackIndex;
size_t finalPosition = endIsAuto ? lastPosition : positions.resolvedFinalPosition() - 1;
// Positioned children do not grow the grid, so we need to clamp the positions to avoid ending up outside of it.
initialPosition = std::min(initialPosition, lastPosition);
finalPosition = std::min(finalPosition, lastPosition);
LayoutUnit start = startIsAuto ? LayoutUnit() : (direction == ForColumns) ? m_columnPositions[initialPosition] : m_rowPositions[initialPosition];
LayoutUnit end = endIsAuto ? (direction == ForColumns) ? logicalWidth() : logicalHeight() : (direction == ForColumns) ? m_columnPositions[finalPosition + 1] : m_rowPositions[finalPosition + 1];
breadth = end - start;
if (startIsAuto)
breadth -= (direction == ForColumns) ? borderStart() : borderBefore();
else
start -= ((direction == ForColumns) ? borderStart() : borderBefore());
if (endIsAuto) {
breadth -= (direction == ForColumns) ? borderEnd() : borderAfter();
breadth -= scrollbarLogicalWidth();
}
offset = start;
if (child.parent() == this && !startIsAuto) {
// If column/row start is "auto" the static position has been already set in prepareChildForPositionedLayout().
PaintLayer* childLayer = child.layer();
if (direction == ForColumns)
childLayer->setStaticInlinePosition(borderStart() + offset);
else
childLayer->setStaticBlockPosition(borderBefore() + offset);
}
}
GridCoordinate LayoutGrid::cachedGridCoordinate(const LayoutBox& gridItem) const
{
ASSERT(m_gridItemCoordinate.contains(&gridItem));
return m_gridItemCoordinate.get(&gridItem);
}
GridSpan LayoutGrid::cachedGridSpan(const LayoutBox& gridItem, GridTrackSizingDirection direction) const
{
GridCoordinate coordinate = cachedGridCoordinate(gridItem);
return direction == ForColumns ? coordinate.columns : coordinate.rows;
}
LayoutUnit LayoutGrid::gridAreaBreadthForChild(const LayoutBox& child, GridTrackSizingDirection direction, const Vector<GridTrack>& tracks) const
{
const GridSpan& span = cachedGridSpan(child, direction);
LayoutUnit gridAreaBreadth = 0;
for (const auto& trackPosition : span)
gridAreaBreadth += tracks[trackPosition].baseSize();
gridAreaBreadth += guttersSize(direction, span.integerSpan());
return gridAreaBreadth;
}
LayoutUnit LayoutGrid::gridAreaBreadthForChildIncludingAlignmentOffsets(const LayoutBox& child, GridTrackSizingDirection direction, const GridSizingData& sizingData) const
{
// We need the cached value when available because Content Distribution alignment properties
// may have some influence in the final grid area breadth.
const Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
const GridSpan& span = cachedGridSpan(child, direction);
const Vector<LayoutUnit>& linePositions = (direction == ForColumns) ? m_columnPositions : m_rowPositions;
LayoutUnit initialTrackPosition = linePositions[span.resolvedInitialPosition()];
LayoutUnit finalTrackPosition = linePositions[span.resolvedFinalPosition() - 1];
// Track Positions vector stores the 'start' grid line of each track, so w have to add last track's baseSize.
return finalTrackPosition - initialTrackPosition + tracks[span.resolvedFinalPosition() - 1].baseSize();
}
void LayoutGrid::populateGridPositions(GridSizingData& sizingData)
{
// Since we add alignment offsets and track gutters, grid lines are not always adjacent. Hence we will have to
// assume from now on that we just store positions of the initial grid lines of each track,
// except the last one, which is the only one considered as a final grid line of a track.
// FIXME: This will affect the computed style value of grid tracks size, since we are
// using these positions to compute them.
unsigned numberOfTracks = sizingData.columnTracks.size();
unsigned numberOfLines = numberOfTracks + 1;
unsigned lastLine = numberOfLines - 1;
unsigned nextToLastLine = numberOfLines - 2;
ContentAlignmentData offset = computeContentPositionAndDistributionOffset(ForColumns, sizingData.freeSpaceForDirection(ForColumns), numberOfTracks);
LayoutUnit trackGap = guttersSize(ForColumns, 2);
m_columnPositions.resize(numberOfLines);
m_columnPositions[0] = borderAndPaddingStart() + offset.positionOffset;
for (unsigned i = 0; i < lastLine; ++i)
m_columnPositions[i + 1] = m_columnPositions[i] + offset.distributionOffset + sizingData.columnTracks[i].baseSize() + trackGap;
m_columnPositions[lastLine] = m_columnPositions[nextToLastLine] + sizingData.columnTracks[nextToLastLine].baseSize();
numberOfTracks = sizingData.rowTracks.size();
numberOfLines = numberOfTracks + 1;
lastLine = numberOfLines - 1;
nextToLastLine = numberOfLines - 2;
offset = computeContentPositionAndDistributionOffset(ForRows, sizingData.freeSpaceForDirection(ForRows), numberOfTracks);
trackGap = guttersSize(ForRows, 2);
m_rowPositions.resize(numberOfLines);
m_rowPositions[0] = borderAndPaddingBefore() + offset.positionOffset;
for (unsigned i = 0; i < lastLine; ++i)
m_rowPositions[i + 1] = m_rowPositions[i] + offset.distributionOffset + sizingData.rowTracks[i].baseSize() + trackGap;
m_rowPositions[lastLine] = m_rowPositions[nextToLastLine] + sizingData.rowTracks[nextToLastLine].baseSize();
}
static LayoutUnit computeOverflowAlignmentOffset(OverflowAlignment overflow, LayoutUnit trackBreadth, LayoutUnit childBreadth)
{
LayoutUnit offset = trackBreadth - childBreadth;
switch (overflow) {
case OverflowAlignmentSafe:
// If overflow is 'safe', we have to make sure we don't overflow the 'start'
// edge (potentially cause some data loss as the overflow is unreachable).
return std::max<LayoutUnit>(0, offset);
case OverflowAlignmentTrue:
case OverflowAlignmentDefault:
// If we overflow our alignment container and overflow is 'true' (default), we
// ignore the overflow and just return the value regardless (which may cause data
// loss as we overflow the 'start' edge).
return offset;
}
ASSERT_NOT_REACHED();
return 0;
}
static inline LayoutUnit constrainedChildIntrinsicContentLogicalHeight(const LayoutBox& child)
{
LayoutUnit childIntrinsicContentLogicalHeight = child.intrinsicContentLogicalHeight();
return child.constrainLogicalHeightByMinMax(childIntrinsicContentLogicalHeight + child.borderAndPaddingLogicalHeight(), childIntrinsicContentLogicalHeight);
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
bool LayoutGrid::needToStretchChildLogicalHeight(const LayoutBox& child) const
{
if (ComputedStyle::resolveAlignment(styleRef(), child.styleRef(), ItemPositionStretch) != ItemPositionStretch)
return false;
return isHorizontalWritingMode() && child.style()->height().isAuto();
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
LayoutUnit LayoutGrid::childIntrinsicHeight(const LayoutBox& child) const
{
if (child.isHorizontalWritingMode() && needToStretchChildLogicalHeight(child))
return constrainedChildIntrinsicContentLogicalHeight(child);
return child.size().height();
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
LayoutUnit LayoutGrid::childIntrinsicWidth(const LayoutBox& child) const
{
if (!child.isHorizontalWritingMode() && needToStretchChildLogicalHeight(child))
return constrainedChildIntrinsicContentLogicalHeight(child);
return child.size().width();
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
LayoutUnit LayoutGrid::intrinsicLogicalHeightForChild(const LayoutBox& child) const
{
return isHorizontalWritingMode() ? childIntrinsicHeight(child) : childIntrinsicWidth(child);
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
LayoutUnit LayoutGrid::marginLogicalHeightForChild(const LayoutBox& child) const
{
return isHorizontalWritingMode() ? child.marginHeight() : child.marginWidth();
}
LayoutUnit LayoutGrid::computeMarginLogicalHeightForChild(const LayoutBox& child) const
{
if (!child.styleRef().hasMargin())
return 0;
LayoutUnit marginBefore;
LayoutUnit marginAfter;
child.computeMarginsForDirection(BlockDirection, this, child.containingBlockLogicalWidthForContent(), child.logicalHeight(), marginBefore, marginAfter,
child.style()->marginBeforeUsing(style()),
child.style()->marginAfterUsing(style()));
return marginBefore + marginAfter;
}
LayoutUnit LayoutGrid::availableAlignmentSpaceForChildBeforeStretching(LayoutUnit gridAreaBreadthForChild, const LayoutBox& child) const
{
// Because we want to avoid multiple layouts, stretching logic might be performed before
// children are laid out, so we can't use the child cached values. Hence, we need to
// compute margins in order to determine the available height before stretching.
return gridAreaBreadthForChild - (child.needsLayout() ? computeMarginLogicalHeightForChild(child) : marginLogicalHeightForChild(child));
}
// FIXME: This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
void LayoutGrid::applyStretchAlignmentToChildIfNeeded(LayoutBox& child)
{
// We clear height override values because we will decide now whether it's allowed or
// not, evaluating the conditions which might have changed since the old values were set.
child.clearOverrideLogicalContentHeight();
auto& childStyle = child.styleRef();
bool isHorizontalMode = isHorizontalWritingMode();
bool hasAutoSizeInColumnAxis = isHorizontalMode ? childStyle.height().isAuto() : childStyle.width().isAuto();
bool allowedToStretchChildAlongColumnAxis = hasAutoSizeInColumnAxis && !childStyle.marginBeforeUsing(style()).isAuto() && !childStyle.marginAfterUsing(style()).isAuto();
if (allowedToStretchChildAlongColumnAxis && ComputedStyle::resolveAlignment(styleRef(), childStyle, ItemPositionStretch) == ItemPositionStretch) {
// TODO (lajava): If the child has orthogonal flow, then it already has an override height set, so use it.
// TODO (lajava): grid track sizing and positioning do not support orthogonal modes yet.
if (child.isHorizontalWritingMode() == isHorizontalMode) {
LayoutUnit stretchedLogicalHeight = availableAlignmentSpaceForChildBeforeStretching(child.overrideContainingBlockContentLogicalHeight(), child);
LayoutUnit desiredLogicalHeight = child.constrainLogicalHeightByMinMax(stretchedLogicalHeight, -1);
child.setOverrideLogicalContentHeight(desiredLogicalHeight - child.borderAndPaddingLogicalHeight());
if (desiredLogicalHeight != child.logicalHeight()) {
// TODO (lajava): Can avoid laying out here in some cases. See https://webkit.org/b/87905.
child.setLogicalHeight(0);
child.setNeedsLayout(LayoutInvalidationReason::GridChanged);
}
}
}
}
// TODO(lajava): This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
bool LayoutGrid::hasAutoMarginsInColumnAxis(const LayoutBox& child) const
{
if (isHorizontalWritingMode())
return child.style()->marginTop().isAuto() || child.style()->marginBottom().isAuto();
return child.style()->marginLeft().isAuto() || child.style()->marginRight().isAuto();
}
// TODO(lajava): This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
bool LayoutGrid::hasAutoMarginsInRowAxis(const LayoutBox& child) const
{
if (isHorizontalWritingMode())
return child.style()->marginLeft().isAuto() || child.style()->marginRight().isAuto();
return child.style()->marginTop().isAuto() || child.style()->marginBottom().isAuto();
}
// TODO(lajava): This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
void LayoutGrid::updateAutoMarginsInRowAxisIfNeeded(LayoutBox& child)
{
ASSERT(!child.isOutOfFlowPositioned());
LayoutUnit availableAlignmentSpace = child.overrideContainingBlockContentLogicalWidth() - child.logicalWidth() - child.marginLogicalWidth();
if (availableAlignmentSpace <= 0)
return;
Length marginStart = child.style()->marginStartUsing(style());
Length marginEnd = child.style()->marginEndUsing(style());
if (marginStart.isAuto() && marginEnd.isAuto()) {
child.setMarginStart(availableAlignmentSpace / 2, style());
child.setMarginEnd(availableAlignmentSpace / 2, style());
} else if (marginStart.isAuto()) {
child.setMarginStart(availableAlignmentSpace, style());
} else if (marginEnd.isAuto()) {
child.setMarginEnd(availableAlignmentSpace, style());
}
}
// TODO(lajava): This logic is shared by LayoutFlexibleBox, so it should be moved to LayoutBox.
void LayoutGrid::updateAutoMarginsInColumnAxisIfNeeded(LayoutBox& child)
{
ASSERT(!child.isOutOfFlowPositioned());
LayoutUnit availableAlignmentSpace = child.overrideContainingBlockContentLogicalHeight() - child.logicalHeight() - child.marginLogicalHeight();
if (availableAlignmentSpace <= 0)
return;
Length marginBefore = child.style()->marginBeforeUsing(style());
Length marginAfter = child.style()->marginAfterUsing(style());
if (marginBefore.isAuto() && marginAfter.isAuto()) {
child.setMarginBefore(availableAlignmentSpace / 2, style());
child.setMarginAfter(availableAlignmentSpace / 2, style());
} else if (marginBefore.isAuto()) {
child.setMarginBefore(availableAlignmentSpace, style());
} else if (marginAfter.isAuto()) {
child.setMarginAfter(availableAlignmentSpace, style());
}
}
GridAxisPosition LayoutGrid::columnAxisPositionForChild(const LayoutBox& child) const
{
bool hasOrthogonalWritingMode = child.isHorizontalWritingMode() != isHorizontalWritingMode();
bool hasSameWritingMode = child.styleRef().writingMode() == styleRef().writingMode();
switch (ComputedStyle::resolveAlignment(styleRef(), child.styleRef(), ItemPositionStretch)) {
case ItemPositionSelfStart:
// If orthogonal writing-modes, this computes to 'start'.
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
// self-start is based on the child's block axis direction. That's why we need to check against the grid container's block flow.
return (hasOrthogonalWritingMode || hasSameWritingMode) ? GridAxisStart : GridAxisEnd;
case ItemPositionSelfEnd:
// If orthogonal writing-modes, this computes to 'end'.
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
// self-end is based on the child's block axis direction. That's why we need to check against the grid container's block flow.
return (hasOrthogonalWritingMode || hasSameWritingMode) ? GridAxisEnd : GridAxisStart;
case ItemPositionLeft:
// The alignment axis (column axis) and the inline axis are parallell in
// orthogonal writing mode. Otherwise this this is equivalent to 'start'.
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
return GridAxisStart;
case ItemPositionRight:
// The alignment axis (column axis) and the inline axis are parallell in
// orthogonal writing mode. Otherwise this this is equivalent to 'start'.
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
return hasOrthogonalWritingMode ? GridAxisEnd : GridAxisStart;
case ItemPositionCenter:
return GridAxisCenter;
case ItemPositionFlexStart: // Only used in flex layout, otherwise equivalent to 'start'.
case ItemPositionStart:
return GridAxisStart;
case ItemPositionFlexEnd: // Only used in flex layout, otherwise equivalent to 'end'.
case ItemPositionEnd:
return GridAxisEnd;
case ItemPositionStretch:
return GridAxisStart;
case ItemPositionBaseline:
case ItemPositionLastBaseline:
// FIXME: These two require implementing Baseline Alignment. For now, we always 'start' align the child.
// crbug.com/234191
return GridAxisStart;
case ItemPositionAuto:
break;
}
ASSERT_NOT_REACHED();
return GridAxisStart;
}
GridAxisPosition LayoutGrid::rowAxisPositionForChild(const LayoutBox& child) const
{
bool hasOrthogonalWritingMode = child.isHorizontalWritingMode() != isHorizontalWritingMode();
bool hasSameDirection = child.styleRef().direction() == styleRef().direction();
bool isLTR = styleRef().isLeftToRightDirection();
switch (ComputedStyle::resolveJustification(styleRef(), child.styleRef(), ItemPositionStretch)) {
case ItemPositionSelfStart:
// For orthogonal writing-modes, this computes to 'start'
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
// self-start is based on the child's direction. That's why we need to check against the grid container's direction.
return (hasOrthogonalWritingMode || hasSameDirection) ? GridAxisStart : GridAxisEnd;
case ItemPositionSelfEnd:
// For orthogonal writing-modes, this computes to 'start'
// FIXME: grid track sizing and positioning do not support orthogonal modes yet.
return (hasOrthogonalWritingMode || hasSameDirection) ? GridAxisEnd : GridAxisStart;
case ItemPositionLeft:
return isLTR ? GridAxisStart : GridAxisEnd;
case ItemPositionRight:
return isLTR ? GridAxisEnd : GridAxisStart;
case ItemPositionCenter:
return GridAxisCenter;
case ItemPositionFlexStart: // Only used in flex layout, otherwise equivalent to 'start'.
case ItemPositionStart:
return GridAxisStart;
case ItemPositionFlexEnd: // Only used in flex layout, otherwise equivalent to 'end'.
case ItemPositionEnd:
return GridAxisEnd;
case ItemPositionStretch:
return GridAxisStart;
case ItemPositionBaseline:
case ItemPositionLastBaseline:
// FIXME: These two require implementing Baseline Alignment. For now, we always 'start' align the child.
// crbug.com/234191
return GridAxisStart;
case ItemPositionAuto:
break;
}
ASSERT_NOT_REACHED();
return GridAxisStart;
}
static inline LayoutUnit offsetBetweenTracks(ContentDistributionType distribution, const Vector<LayoutUnit>& trackPositions, const LayoutUnit& childBreadth)
{
return (distribution == ContentDistributionStretch || ContentDistributionStretch == ContentDistributionDefault) ? LayoutUnit() : trackPositions[1] - trackPositions[0] - childBreadth;
}
LayoutUnit LayoutGrid::columnAxisOffsetForChild(const LayoutBox& child) const
{
const GridSpan& rowsSpan = cachedGridSpan(child, ForRows);
size_t childStartLine = rowsSpan.resolvedInitialPosition();
LayoutUnit startOfRow = m_rowPositions[childStartLine];
LayoutUnit startPosition = startOfRow + marginBeforeForChild(child);
if (hasAutoMarginsInColumnAxis(child))
return startPosition;
GridAxisPosition axisPosition = columnAxisPositionForChild(child);
switch (axisPosition) {
case GridAxisStart:
return startPosition;
case GridAxisEnd:
case GridAxisCenter: {
size_t childEndLine = rowsSpan.resolvedFinalPosition();
LayoutUnit endOfRow = m_rowPositions[childEndLine];
// m_rowPositions include gutters so we need to substract them to get the actual end position for a given
// row (this does not have to be done for the last track as there are no more m_rowPositions after it)
if (childEndLine < m_rowPositions.size() - 1)
endOfRow -= guttersSize(ForRows, 2);
LayoutUnit childBreadth = child.logicalHeight() + child.marginLogicalHeight();
if (childEndLine - childStartLine > 1 && childEndLine < m_rowPositions.size() - 1)
endOfRow -= offsetBetweenTracks(styleRef().alignContentDistribution(), m_rowPositions, childBreadth);
LayoutUnit offsetFromStartPosition = computeOverflowAlignmentOffset(child.styleRef().alignSelfOverflowAlignment(), endOfRow - startOfRow, childBreadth);
return startPosition + (axisPosition == GridAxisEnd ? offsetFromStartPosition : offsetFromStartPosition / 2);
}
}
ASSERT_NOT_REACHED();
return 0;
}
LayoutUnit LayoutGrid::rowAxisOffsetForChild(const LayoutBox& child) const
{
const GridSpan& columnsSpan = cachedGridSpan(child, ForColumns);
size_t childStartLine = columnsSpan.resolvedInitialPosition();
LayoutUnit startOfColumn = m_columnPositions[childStartLine];
LayoutUnit startPosition = startOfColumn + marginStartForChild(child);
if (hasAutoMarginsInRowAxis(child))
return startPosition;
GridAxisPosition axisPosition = rowAxisPositionForChild(child);
switch (axisPosition) {
case GridAxisStart:
return startPosition;
case GridAxisEnd:
case GridAxisCenter: {
size_t childEndLine = columnsSpan.resolvedFinalPosition();
LayoutUnit endOfColumn = m_columnPositions[childEndLine];
// m_columnPositions include gutters so we need to substract them to get the actual end position for a given
// column (this does not have to be done for the last track as there are no more m_columnPositions after it)
if (childEndLine < m_columnPositions.size() - 1)
endOfColumn -= guttersSize(ForRows, 2);
LayoutUnit childBreadth = child.logicalWidth() + child.marginLogicalWidth();
if (childEndLine - childStartLine > 1 && childEndLine < m_columnPositions.size() - 1)
endOfColumn -= offsetBetweenTracks(styleRef().justifyContentDistribution(), m_columnPositions, childBreadth);
LayoutUnit offsetFromStartPosition = computeOverflowAlignmentOffset(child.styleRef().justifySelfOverflowAlignment(), endOfColumn - startOfColumn, childBreadth);
return startPosition + (axisPosition == GridAxisEnd ? offsetFromStartPosition : offsetFromStartPosition / 2);
}
}
ASSERT_NOT_REACHED();
return 0;
}
ContentPosition static resolveContentDistributionFallback(ContentDistributionType distribution)
{
switch (distribution) {
case ContentDistributionSpaceBetween:
return ContentPositionStart;
case ContentDistributionSpaceAround:
return ContentPositionCenter;
case ContentDistributionSpaceEvenly:
return ContentPositionCenter;
case ContentDistributionStretch:
return ContentPositionStart;
case ContentDistributionDefault:
return ContentPositionAuto;
}
ASSERT_NOT_REACHED();
return ContentPositionAuto;
}
static inline LayoutUnit offsetToStartEdge(bool isLeftToRight, LayoutUnit availableSpace)
{
return isLeftToRight ? LayoutUnit() : availableSpace;
}
static inline LayoutUnit offsetToEndEdge(bool isLeftToRight, LayoutUnit availableSpace)
{
return !isLeftToRight ? LayoutUnit() : availableSpace;
}
static ContentAlignmentData contentDistributionOffset(const LayoutUnit& availableFreeSpace, ContentPosition& fallbackPosition, ContentDistributionType distribution, unsigned numberOfGridTracks)
{
if (distribution != ContentDistributionDefault && fallbackPosition == ContentPositionAuto)
fallbackPosition = resolveContentDistributionFallback(distribution);
if (availableFreeSpace <= 0)
return {};
LayoutUnit distributionOffset;
switch (distribution) {
case ContentDistributionSpaceBetween:
if (numberOfGridTracks < 2)
return {};
return {0, availableFreeSpace / (numberOfGridTracks - 1)};
case ContentDistributionSpaceAround:
if (numberOfGridTracks < 1)
return {};
distributionOffset = availableFreeSpace / numberOfGridTracks;
return {distributionOffset / 2, distributionOffset};
case ContentDistributionSpaceEvenly:
distributionOffset = availableFreeSpace / (numberOfGridTracks + 1);
return {distributionOffset, distributionOffset};
case ContentDistributionStretch:
return {0, 0};
case ContentDistributionDefault:
return {};
}
ASSERT_NOT_REACHED();
return {};
}
ContentAlignmentData LayoutGrid::computeContentPositionAndDistributionOffset(GridTrackSizingDirection direction, const LayoutUnit& availableFreeSpace, unsigned numberOfGridTracks) const
{
bool isRowAxis = direction == ForColumns;
ContentPosition position = isRowAxis ? styleRef().justifyContentPosition() : styleRef().alignContentPosition();
ContentDistributionType distribution = isRowAxis ? styleRef().justifyContentDistribution() : styleRef().alignContentDistribution();
// If <content-distribution> value can't be applied, 'position' will become the associated
// <content-position> fallback value.
ContentAlignmentData contentAlignment = contentDistributionOffset(availableFreeSpace, position, distribution, numberOfGridTracks);
if (contentAlignment.isValid())
return contentAlignment;
OverflowAlignment overflow = isRowAxis ? styleRef().justifyContentOverflowAlignment() : styleRef().alignContentOverflowAlignment();
if (availableFreeSpace <= 0 && overflow == OverflowAlignmentSafe)
return {0, 0};
switch (position) {
case ContentPositionLeft:
// The align-content's axis is always orthogonal to the inline-axis.
return {0, 0};
case ContentPositionRight:
if (isRowAxis)
return {availableFreeSpace, 0};
// The align-content's axis is always orthogonal to the inline-axis.
return {0, 0};
case ContentPositionCenter:
return {availableFreeSpace / 2, 0};
case ContentPositionFlexEnd: // Only used in flex layout, for other layout, it's equivalent to 'End'.
case ContentPositionEnd:
if (isRowAxis)
return {offsetToEndEdge(styleRef().isLeftToRightDirection(), availableFreeSpace), 0};
return {availableFreeSpace, 0};
case ContentPositionFlexStart: // Only used in flex layout, for other layout, it's equivalent to 'Start'.
case ContentPositionStart:
if (isRowAxis)
return {offsetToStartEdge(styleRef().isLeftToRightDirection(), availableFreeSpace), 0};
return {0, 0};
case ContentPositionBaseline:
case ContentPositionLastBaseline:
// FIXME: These two require implementing Baseline Alignment. For now, we always 'start' align the child.
// crbug.com/234191
if (isRowAxis)
return {offsetToStartEdge(styleRef().isLeftToRightDirection(), availableFreeSpace), 0};
return {0, 0};
case ContentPositionAuto:
break;
}
ASSERT_NOT_REACHED();
return {0, 0};
}
LayoutPoint LayoutGrid::findChildLogicalPosition(const LayoutBox& child, GridSizingData& sizingData) const
{
LayoutUnit rowAxisOffset = rowAxisOffsetForChild(child);
// We stored m_columnPosition s's data ignoring the direction, hence we might need now
// to translate positions from RTL to LTR, as it's more convenient for painting.
if (!style()->isLeftToRightDirection()) {
LayoutUnit alignmentOffset = m_columnPositions[0] - borderAndPaddingStart();
LayoutUnit rightGridEdgePosition = m_columnPositions[m_columnPositions.size() - 1] + alignmentOffset + borderAndPaddingLogicalLeft();
rowAxisOffset = rightGridEdgePosition - (rowAxisOffset + child.logicalWidth());
}
return LayoutPoint(rowAxisOffset, columnAxisOffsetForChild(child));
}
void LayoutGrid::paintChildren(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) const
{
GridPainter(*this).paintChildren(paintInfo, paintOffset);
}
} // namespace blink