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/*
* Copyright (C) 2017 Igalia S.L.
*
* 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 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 "GridTrackSizingAlgorithm.h"
#include "Grid.h"
#include "GridArea.h"
#include "GridLayoutFunctions.h"
#include "RenderGrid.h"
namespace WebCore {
const LayoutUnit& GridTrack::baseSize() const
{
ASSERT(isGrowthLimitBiggerThanBaseSize());
return m_baseSize;
}
const LayoutUnit& GridTrack::growthLimit() const
{
ASSERT(isGrowthLimitBiggerThanBaseSize());
ASSERT(!m_growthLimitCap || m_growthLimitCap.value() >= m_growthLimit || m_baseSize >= m_growthLimitCap.value());
return m_growthLimit;
}
void GridTrack::setBaseSize(LayoutUnit baseSize)
{
m_baseSize = baseSize;
ensureGrowthLimitIsBiggerThanBaseSize();
}
void GridTrack::setGrowthLimit(LayoutUnit growthLimit)
{
m_growthLimit = growthLimit == infinity ? growthLimit : std::min(growthLimit, m_growthLimitCap.value_or(growthLimit));
ensureGrowthLimitIsBiggerThanBaseSize();
}
const LayoutUnit& GridTrack::growthLimitIfNotInfinite() const
{
ASSERT(isGrowthLimitBiggerThanBaseSize());
return m_growthLimit == infinity ? m_baseSize : m_growthLimit;
}
void GridTrack::setTempSize(const LayoutUnit& tempSize)
{
ASSERT(tempSize >= 0);
ASSERT(growthLimitIsInfinite() || growthLimit() >= tempSize);
m_tempSize = tempSize;
}
void GridTrack::growTempSize(const LayoutUnit& tempSize)
{
ASSERT(tempSize >= 0);
m_tempSize += tempSize;
}
void GridTrack::setGrowthLimitCap(std::optional<LayoutUnit> growthLimitCap)
{
ASSERT(!growthLimitCap || growthLimitCap.value() >= 0);
m_growthLimitCap = growthLimitCap;
}
void GridTrack::setCachedTrackSize(const GridTrackSize& cachedTrackSize)
{
m_cachedTrackSize = cachedTrackSize;
}
void GridTrack::ensureGrowthLimitIsBiggerThanBaseSize()
{
if (m_growthLimit != infinity && m_growthLimit < m_baseSize)
m_growthLimit = m_baseSize;
}
// Static helper methods.
static GridAxis gridAxisForDirection(GridTrackSizingDirection direction)
{
return direction == ForColumns ? GridRowAxis : GridColumnAxis;
}
static GridTrackSizingDirection gridDirectionForAxis(GridAxis axis)
{
return axis == GridRowAxis ? ForColumns : ForRows;
}
static bool hasRelativeMarginOrPaddingForChild(const RenderBox& child, GridTrackSizingDirection direction)
{
if (direction == ForColumns)
return child.style().marginStart().isPercentOrCalculated() || child.style().marginEnd().isPercentOrCalculated() || child.style().paddingStart().isPercentOrCalculated() || child.style().paddingEnd().isPercentOrCalculated();
return child.style().marginBefore().isPercentOrCalculated() || child.style().marginAfter().isPercentOrCalculated() || child.style().paddingBefore().isPercentOrCalculated() || child.style().paddingAfter().isPercentOrCalculated();
}
static bool hasRelativeOrIntrinsicSizeForChild(const RenderBox& child, GridTrackSizingDirection direction)
{
if (direction == ForColumns)
return child.hasRelativeLogicalWidth() || child.style().logicalWidth().isIntrinsicOrAuto();
return child.hasRelativeLogicalHeight() || child.style().logicalHeight().isIntrinsicOrAuto();
}
static bool shouldClearOverridingContainingBlockContentSizeForChild(const RenderBox& child, GridTrackSizingDirection direction)
{
return hasRelativeOrIntrinsicSizeForChild(child, direction) || hasRelativeMarginOrPaddingForChild(child, direction);
}
static void setOverridingContainingBlockContentSizeForChild(const RenderGrid& grid, RenderBox& child, GridTrackSizingDirection direction, std::optional<LayoutUnit> size)
{
// This function sets the dimension based on the writing mode of the containing block.
// For subgrids, this might not be the outermost grid, but could be a subgrid. If the
// writing mode of the CB and the grid for which we're doing sizing don't match, swap
// the directions.
direction = GridLayoutFunctions::flowAwareDirectionForChild(grid, *child.containingBlock(), direction);
if (direction == ForColumns)
child.setOverridingContainingBlockContentLogicalWidth(size);
else
child.setOverridingContainingBlockContentLogicalHeight(size);
}
// GridTrackSizingAlgorithm private.
void GridTrackSizingAlgorithm::setFreeSpace(GridTrackSizingDirection direction, std::optional<LayoutUnit> freeSpace)
{
if (direction == ForColumns)
m_freeSpaceColumns = freeSpace;
else
m_freeSpaceRows = freeSpace;
}
std::optional<LayoutUnit> GridTrackSizingAlgorithm::availableSpace() const
{
ASSERT(wasSetup());
return availableSpace(m_direction);
}
void GridTrackSizingAlgorithm::setAvailableSpace(GridTrackSizingDirection direction, std::optional<LayoutUnit> availableSpace)
{
if (direction == ForColumns)
m_availableSpaceColumns = availableSpace;
else
m_availableSpaceRows = availableSpace;
}
const GridTrackSize& GridTrackSizingAlgorithm::rawGridTrackSize(GridTrackSizingDirection direction, unsigned translatedIndex) const
{
bool isRowAxis = direction == ForColumns;
auto& renderStyle = m_renderGrid->style();
auto& trackStyles = isRowAxis ? renderStyle.gridColumns() : renderStyle.gridRows();
auto& autoRepeatTrackStyles = isRowAxis ? renderStyle.gridAutoRepeatColumns() : renderStyle.gridAutoRepeatRows();
auto& autoTrackStyles = isRowAxis ? renderStyle.gridAutoColumns() : renderStyle.gridAutoRows();
unsigned insertionPoint = isRowAxis ? renderStyle.gridAutoRepeatColumnsInsertionPoint() : renderStyle.gridAutoRepeatRowsInsertionPoint();
unsigned autoRepeatTracksCount = m_grid.autoRepeatTracks(direction);
// We should not use GridPositionsResolver::explicitGridXXXCount() for this because the
// explicit grid might be larger than the number of tracks in grid-template-rows|columns (if
// grid-template-areas is specified for example).
unsigned explicitTracksCount = trackStyles.size() + autoRepeatTracksCount;
int untranslatedIndexAsInt = translatedIndex - m_grid.explicitGridStart(direction);
unsigned autoTrackStylesSize = autoTrackStyles.size();
if (untranslatedIndexAsInt < 0) {
int index = untranslatedIndexAsInt % static_cast<int>(autoTrackStylesSize);
// We need to traspose the index because the first negative implicit line will get the last defined auto track and so on.
index += index ? autoTrackStylesSize : 0;
ASSERT(index >= 0);
return autoTrackStyles[index];
}
unsigned untranslatedIndex = static_cast<unsigned>(untranslatedIndexAsInt);
if (untranslatedIndex >= explicitTracksCount)
return autoTrackStyles[(untranslatedIndex - explicitTracksCount) % autoTrackStylesSize];
if (!autoRepeatTracksCount || untranslatedIndex < insertionPoint)
return trackStyles[untranslatedIndex];
if (untranslatedIndex < (insertionPoint + autoRepeatTracksCount)) {
unsigned autoRepeatLocalIndex = untranslatedIndexAsInt - insertionPoint;
return autoRepeatTrackStyles[autoRepeatLocalIndex % autoRepeatTrackStyles.size()];
}
return trackStyles[untranslatedIndex - autoRepeatTracksCount];
}
LayoutUnit GridTrackSizingAlgorithm::computeTrackBasedSize() const
{
LayoutUnit size;
auto& allTracks = tracks(m_direction);
for (auto& track : allTracks)
size += track.baseSize();
size += m_renderGrid->guttersSize(m_grid, m_direction, 0, allTracks.size(), availableSpace());
return size;
}
LayoutUnit GridTrackSizingAlgorithm::initialBaseSize(const GridTrackSize& trackSize) const
{
const GridLength& gridLength = trackSize.minTrackBreadth();
if (gridLength.isFlex())
return 0;
const Length& trackLength = gridLength.length();
if (trackLength.isSpecified())
return valueForLength(trackLength, std::max<LayoutUnit>(availableSpace().value_or(0), 0));
ASSERT(trackLength.isMinContent() || trackLength.isAuto() || trackLength.isMaxContent());
return 0;
}
LayoutUnit GridTrackSizingAlgorithm::initialGrowthLimit(const GridTrackSize& trackSize, LayoutUnit baseSize) const
{
const GridLength& gridLength = trackSize.maxTrackBreadth();
if (gridLength.isFlex())
return trackSize.minTrackBreadth().isContentSized() ? LayoutUnit(infinity) : baseSize;
const Length& trackLength = gridLength.length();
if (trackLength.isSpecified())
return valueForLength(trackLength, std::max<LayoutUnit>(availableSpace().value_or(0), 0));
ASSERT(trackLength.isMinContent() || trackLength.isAuto() || trackLength.isMaxContent());
return infinity;
}
void GridTrackSizingAlgorithm::sizeTrackToFitNonSpanningItem(const GridSpan& span, RenderBox& gridItem, GridTrack& track)
{
unsigned trackPosition = span.startLine();
const auto& trackSize = tracks(m_direction)[trackPosition].cachedTrackSize();
if (trackSize.hasMinContentMinTrackBreadth()) {
track.setBaseSize(std::max(track.baseSize(), m_strategy->minContentForChild(gridItem)));
} else if (trackSize.hasMaxContentMinTrackBreadth()) {
track.setBaseSize(std::max(track.baseSize(), m_strategy->maxContentForChild(gridItem)));
} else if (trackSize.hasAutoMinTrackBreadth()) {
track.setBaseSize(std::max(track.baseSize(), m_strategy->minSizeForChild(gridItem)));
}
if (trackSize.hasMinContentMaxTrackBreadth()) {
track.setGrowthLimit(std::max(track.growthLimit(), m_strategy->minContentForChild(gridItem)));
} else if (trackSize.hasMaxContentOrAutoMaxTrackBreadth()) {
LayoutUnit growthLimit = m_strategy->maxContentForChild(gridItem);
if (trackSize.isFitContent())
growthLimit = std::min(growthLimit, valueForLength(trackSize.fitContentTrackBreadth().length(), availableSpace().value_or(0)));
track.setGrowthLimit(std::max(track.growthLimit(), growthLimit));
}
}
bool GridTrackSizingAlgorithm::spanningItemCrossesFlexibleSizedTracks(const GridSpan& itemSpan) const
{
const Vector<GridTrack>& trackList = tracks(m_direction);
for (auto trackPosition : itemSpan) {
const auto& trackSize = trackList[trackPosition].cachedTrackSize();
if (trackSize.minTrackBreadth().isFlex() || trackSize.maxTrackBreadth().isFlex())
return true;
}
return false;
}
class GridItemWithSpan {
public:
GridItemWithSpan(RenderBox& gridItem, GridSpan span)
: m_gridItem(gridItem)
, m_span(span)
{
}
RenderBox& gridItem() const { return m_gridItem; }
GridSpan span() const { return m_span; }
bool operator<(const GridItemWithSpan other) const { return m_span.integerSpan() < other.m_span.integerSpan(); }
private:
std::reference_wrapper<RenderBox> m_gridItem;
GridSpan m_span;
};
struct GridItemsSpanGroupRange {
Vector<GridItemWithSpan>::iterator rangeStart;
Vector<GridItemWithSpan>::iterator rangeEnd;
};
enum TrackSizeRestriction {
AllowInfinity,
ForbidInfinity,
};
LayoutUnit GridTrackSizingAlgorithm::itemSizeForTrackSizeComputationPhase(TrackSizeComputationPhase phase, RenderBox& gridItem) const
{
switch (phase) {
case ResolveIntrinsicMinimums:
return m_strategy->minSizeForChild(gridItem);
case ResolveContentBasedMinimums:
case ResolveIntrinsicMaximums:
return m_strategy->minContentForChild(gridItem);
case ResolveMaxContentMinimums:
case ResolveMaxContentMaximums:
return m_strategy->maxContentForChild(gridItem);
case MaximizeTracks:
ASSERT_NOT_REACHED();
return 0;
}
ASSERT_NOT_REACHED();
return 0;
}
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.hasIntrinsicMaxTrackBreadth();
case ResolveMaxContentMaximums:
return trackSize.hasMaxContentOrAutoMaxTrackBreadth();
case MaximizeTracks:
ASSERT_NOT_REACHED();
return false;
}
ASSERT_NOT_REACHED();
return false;
}
static LayoutUnit trackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase phase, GridTrack& track, TrackSizeRestriction restriction)
{
switch (phase) {
case ResolveIntrinsicMinimums:
case ResolveContentBasedMinimums:
case ResolveMaxContentMinimums:
case MaximizeTracks:
return track.baseSize();
case ResolveIntrinsicMaximums:
case ResolveMaxContentMaximums:
return restriction == AllowInfinity ? track.growthLimit() : track.growthLimitIfNotInfinite();
}
ASSERT_NOT_REACHED();
return track.baseSize();
}
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();
}
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();
}
template <TrackSizeComputationVariant variant, TrackSizeComputationPhase phase>
void GridTrackSizingAlgorithm::increaseSizesToAccommodateSpanningItems(const GridItemsSpanGroupRange& gridItemsWithSpan)
{
Vector<GridTrack>& allTracks = tracks(m_direction);
for (const auto& trackIndex : m_contentSizedTracksIndex) {
GridTrack& track = allTracks[trackIndex];
track.setPlannedSize(trackSizeForTrackSizeComputationPhase(phase, track, AllowInfinity));
}
Vector<GridTrack*> growBeyondGrowthLimitsTracks;
Vector<GridTrack*> filteredTracks;
for (auto it = gridItemsWithSpan.rangeStart; it != gridItemsWithSpan.rangeEnd; ++it) {
GridItemWithSpan& gridItemWithSpan = *it;
const GridSpan& itemSpan = gridItemWithSpan.span();
ASSERT(variant == TrackSizeComputationVariant::CrossingFlexibleTracks || itemSpan.integerSpan() > 1u);
filteredTracks.shrink(0);
growBeyondGrowthLimitsTracks.shrink(0);
LayoutUnit spanningTracksSize;
for (auto trackPosition : itemSpan) {
GridTrack& track = allTracks[trackPosition];
const auto& trackSize = track.cachedTrackSize();
spanningTracksSize += trackSizeForTrackSizeComputationPhase(phase, track, ForbidInfinity);
if (variant == TrackSizeComputationVariant::CrossingFlexibleTracks && !trackSize.maxTrackBreadth().isFlex())
continue;
if (!shouldProcessTrackForTrackSizeComputationPhase(phase, trackSize))
continue;
filteredTracks.append(&track);
if (trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(phase, trackSize))
growBeyondGrowthLimitsTracks.append(&track);
}
if (filteredTracks.isEmpty())
continue;
spanningTracksSize += m_renderGrid->guttersSize(m_grid, m_direction, itemSpan.startLine(), itemSpan.integerSpan(), availableSpace());
LayoutUnit extraSpace = itemSizeForTrackSizeComputationPhase(phase, gridItemWithSpan.gridItem()) - spanningTracksSize;
extraSpace = std::max<LayoutUnit>(extraSpace, 0);
auto& tracksToGrowBeyondGrowthLimits = growBeyondGrowthLimitsTracks.isEmpty() ? filteredTracks : growBeyondGrowthLimitsTracks;
distributeSpaceToTracks<variant, phase>(filteredTracks, &tracksToGrowBeyondGrowthLimits, extraSpace);
}
for (const auto& trackIndex : m_contentSizedTracksIndex) {
GridTrack& track = allTracks[trackIndex];
markAsInfinitelyGrowableForTrackSizeComputationPhase(phase, track);
updateTrackSizeForTrackSizeComputationPhase(phase, track);
}
}
template <TrackSizeComputationVariant variant>
void GridTrackSizingAlgorithm::increaseSizesToAccommodateSpanningItems(const GridItemsSpanGroupRange& gridItemsWithSpan)
{
increaseSizesToAccommodateSpanningItems<variant, ResolveIntrinsicMinimums>(gridItemsWithSpan);
increaseSizesToAccommodateSpanningItems<variant, ResolveContentBasedMinimums>(gridItemsWithSpan);
increaseSizesToAccommodateSpanningItems<variant, ResolveMaxContentMinimums>(gridItemsWithSpan);
increaseSizesToAccommodateSpanningItems<variant, ResolveIntrinsicMaximums>(gridItemsWithSpan);
increaseSizesToAccommodateSpanningItems<variant, ResolveMaxContentMaximums>(gridItemsWithSpan);
}
template <TrackSizeComputationVariant variant>
static double getSizeDistributionWeight(const GridTrack& track)
{
if (variant != TrackSizeComputationVariant::CrossingFlexibleTracks)
return 0;
ASSERT(track.cachedTrackSize().maxTrackBreadth().isFlex());
return track.cachedTrackSize().maxTrackBreadth().flex();
}
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).
bool track1HasInfiniteGrowthPotentialWithoutCap = track1->infiniteGrowthPotential() && !track1->growthLimitCap();
bool track2HasInfiniteGrowthPotentialWithoutCap = track2->infiniteGrowthPotential() && !track2->growthLimitCap();
if (track1HasInfiniteGrowthPotentialWithoutCap && track2HasInfiniteGrowthPotentialWithoutCap)
return false;
if (track1HasInfiniteGrowthPotentialWithoutCap || track2HasInfiniteGrowthPotentialWithoutCap)
return track2HasInfiniteGrowthPotentialWithoutCap;
LayoutUnit track1Limit = track1->growthLimitCap().value_or(track1->growthLimit());
LayoutUnit track2Limit = track2->growthLimitCap().value_or(track2->growthLimit());
return (track1Limit - track1->baseSize()) < (track2Limit - track2->baseSize());
}
static void clampGrowthShareIfNeeded(TrackSizeComputationPhase phase, const GridTrack& track, LayoutUnit& growthShare)
{
if (phase != ResolveMaxContentMaximums || !track.growthLimitCap())
return;
LayoutUnit distanceToCap = track.growthLimitCap().value() - track.tempSize();
if (distanceToCap <= 0)
return;
growthShare = std::min(growthShare, distanceToCap);
}
template <TrackSizeComputationPhase phase, SpaceDistributionLimit limit>
static void distributeItemIncurredIncreaseToTrack(GridTrack& track, LayoutUnit& freeSpace, double shareFraction)
{
LayoutUnit freeSpaceShare(freeSpace / shareFraction);
LayoutUnit growthShare = limit == SpaceDistributionLimit::BeyondGrowthLimit || track.infiniteGrowthPotential() ? freeSpaceShare : std::min(freeSpaceShare, track.growthLimit() - trackSizeForTrackSizeComputationPhase(phase, track, ForbidInfinity));
clampGrowthShareIfNeeded(phase, track, growthShare);
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.growTempSize(growthShare);
freeSpace -= growthShare;
}
template <TrackSizeComputationVariant variant, TrackSizeComputationPhase phase, SpaceDistributionLimit limit>
static void distributeItemIncurredIncreases(Vector<GridTrack*>& tracks, LayoutUnit& freeSpace)
{
uint32_t tracksSize = tracks.size();
if (!tracksSize)
return;
if (variant == TrackSizeComputationVariant::NotCrossingFlexibleTracks) {
// We have to sort tracks according to their growth potential. This is necessary even when distributing beyond growth limits,
// because there might be tracks with growth limit caps (like the ones with fit-content()) which cannot indefinitely grow over the limits.
std::sort(tracks.begin(), tracks.end(), sortByGridTrackGrowthPotential);
for (uint32_t i = 0; i < tracksSize; ++i) {
ASSERT(!getSizeDistributionWeight<variant>(*tracks[i]));
distributeItemIncurredIncreaseToTrack<phase, limit>(*tracks[i], freeSpace, tracksSize - i);
}
return;
}
// We never grow flex tracks beyond growth limits, since they are infinite.
ASSERT(limit != SpaceDistributionLimit::BeyondGrowthLimit);
// For TrackSizeComputationVariant::CrossingFlexibleTracks we don't distribute equally, we need to take the weights into account.
Vector<double> fractionsOfRemainingSpace(tracksSize);
double weightSum = 0;
for (int32_t i = tracksSize - 1; i >= 0; --i) {
double weight = getSizeDistributionWeight<variant>(*tracks[i]);
weightSum += weight;
fractionsOfRemainingSpace[i] = weightSum > 0 ? weightSum / weight : tracksSize - i;
}
for (uint32_t i = 0; i < tracksSize; ++i) {
// Sorting is not needed for TrackSizeComputationVariant::CrossingFlexibleTracks, since all tracks have an infinite growth potential.
ASSERT(tracks[i]->growthLimitIsInfinite());
distributeItemIncurredIncreaseToTrack<phase, limit>(*tracks[i], freeSpace, fractionsOfRemainingSpace[i]);
}
}
template <TrackSizeComputationVariant variant, TrackSizeComputationPhase phase>
void GridTrackSizingAlgorithm::distributeSpaceToTracks(Vector<GridTrack*>& tracks, Vector<GridTrack*>* growBeyondGrowthLimitsTracks, LayoutUnit& freeSpace) const
{
ASSERT(freeSpace >= 0);
for (auto* track : tracks)
track->setTempSize(trackSizeForTrackSizeComputationPhase(phase, *track, ForbidInfinity));
if (freeSpace > 0)
distributeItemIncurredIncreases<variant, phase, SpaceDistributionLimit::UpToGrowthLimit>(tracks, freeSpace);
if (freeSpace > 0 && growBeyondGrowthLimitsTracks)
distributeItemIncurredIncreases<variant, phase, SpaceDistributionLimit::BeyondGrowthLimit>(*growBeyondGrowthLimitsTracks, freeSpace);
for (auto* track : tracks)
track->setPlannedSize(track->plannedSize() == infinity ? track->tempSize() : std::max(track->plannedSize(), track->tempSize()));
}
std::optional<LayoutUnit> GridTrackSizingAlgorithm::estimatedGridAreaBreadthForChild(const RenderBox& child, GridTrackSizingDirection direction) const
{
const GridSpan& span = m_renderGrid->gridSpanForChild(child, direction);
LayoutUnit gridAreaSize;
bool gridAreaIsIndefinite = false;
std::optional<LayoutUnit> availableSize = availableSpace(direction);
for (auto trackPosition : span) {
// We may need to estimate the grid area size before running the track sizing algorithm in order to perform the pre-layout of orthogonal items.
// We cannot use tracks(direction)[trackPosition].cachedTrackSize() because tracks(direction) is empty, since we are either performing pre-layout
// or are running the track sizing algorithm in the opposite direction and haven't run it in the desired direction yet.
const auto& trackSize = wasSetup() ? calculateGridTrackSize(direction, trackPosition) : rawGridTrackSize(direction, trackPosition);
GridLength maxTrackSize = trackSize.maxTrackBreadth();
if (maxTrackSize.isContentSized() || maxTrackSize.isFlex() || isRelativeGridLengthAsAuto(maxTrackSize, direction))
gridAreaIsIndefinite = true;
else
gridAreaSize += valueForLength(maxTrackSize.length(), availableSize.value_or(0_lu));
}
gridAreaSize += m_renderGrid->guttersSize(m_grid, direction, span.startLine(), span.integerSpan(), availableSize);
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*m_renderGrid, child, ForColumns);
if (gridAreaIsIndefinite)
return direction == childInlineDirection ? std::make_optional(std::max(child.maxPreferredLogicalWidth(), gridAreaSize)) : std::nullopt;
return gridAreaSize;
}
std::optional<LayoutUnit> GridTrackSizingAlgorithm::gridAreaBreadthForChild(const RenderBox& child, GridTrackSizingDirection direction) const
{
bool addContentAlignmentOffset =
direction == ForColumns && (m_sizingState == RowSizingFirstIteration || m_sizingState == RowSizingExtraIterationForSizeContainment);
// To determine the column track's size based on an orthogonal grid item we need it's logical
// height, which may depend on the row track's size. It's possible that the row tracks sizing
// logic has not been performed yet, so we will need to do an estimation.
if (direction == ForRows && (m_sizingState == ColumnSizingFirstIteration || m_sizingState == ColumnSizingExtraIterationForSizeContainment || m_sizingState == ColumnSizingSecondIteration)) {
ASSERT(GridLayoutFunctions::isOrthogonalChild(*m_renderGrid, child));
// FIXME (jfernandez) Content Alignment should account for this heuristic.
// https://github.com/w3c/csswg-drafts/issues/2697
if (m_sizingState == ColumnSizingFirstIteration || m_sizingState == ColumnSizingExtraIterationForSizeContainment)
return estimatedGridAreaBreadthForChild(child, ForRows);
addContentAlignmentOffset = true;
}
const Vector<GridTrack>& allTracks = tracks(direction);
const GridSpan& span = m_renderGrid->gridSpanForChild(child, direction);
LayoutUnit gridAreaBreadth;
for (auto trackPosition : span)
gridAreaBreadth += allTracks[trackPosition].baseSize();
if (addContentAlignmentOffset)
gridAreaBreadth += (span.integerSpan() - 1) * m_renderGrid->gridItemOffset(direction);
gridAreaBreadth += m_renderGrid->guttersSize(m_grid, direction, span.startLine(), span.integerSpan(), availableSpace(direction));
return gridAreaBreadth;
}
bool GridTrackSizingAlgorithm::isRelativeGridLengthAsAuto(const GridLength& length, GridTrackSizingDirection direction) const
{
return length.isPercentage() && !availableSpace(direction);
}
bool GridTrackSizingAlgorithm::isIntrinsicSizedGridArea(const RenderBox& child, GridAxis axis) const
{
ASSERT(wasSetup());
GridTrackSizingDirection direction = gridDirectionForAxis(axis);
const GridSpan& span = m_renderGrid->gridSpanForChild(child, direction);
for (auto trackPosition : span) {
const auto& trackSize = rawGridTrackSize(direction, trackPosition);
// We consider fr units as 'auto' for the min sizing function.
// FIXME(jfernandez): https://github.com/w3c/csswg-drafts/issues/2611
//
// The use of AvailableSize function may imply different results
// for the same item when assuming indefinite or definite size
// constraints depending on the phase we evaluate the item's
// baseline participation.
// FIXME(jfernandez): https://github.com/w3c/csswg-drafts/issues/3046
if (trackSize.isContentSized() || trackSize.isFitContent() || trackSize.minTrackBreadth().isFlex() || (trackSize.maxTrackBreadth().isFlex() && !availableSpace(direction)))
return true;
}
return false;
}
GridTrackSize GridTrackSizingAlgorithm::calculateGridTrackSize(GridTrackSizingDirection direction, unsigned translatedIndex) const
{
ASSERT(wasSetup());
// Collapse empty auto repeat tracks if auto-fit.
if (m_grid.hasAutoRepeatEmptyTracks(direction) && m_grid.isEmptyAutoRepeatTrack(direction, translatedIndex))
return { Length(LengthType::Fixed), LengthTrackSizing };
auto& trackSize = rawGridTrackSize(direction, translatedIndex);
if (trackSize.isFitContent())
return isRelativeGridLengthAsAuto(trackSize.fitContentTrackBreadth(), direction) ? GridTrackSize(Length(LengthType::Auto), Length(LengthType::MaxContent)) : trackSize;
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 (isRelativeGridLengthAsAuto(trackSize.minTrackBreadth(), direction))
minTrackBreadth = Length(LengthType::Auto);
if (isRelativeGridLengthAsAuto(trackSize.maxTrackBreadth(), direction))
maxTrackBreadth = Length(LengthType::Auto);
// Flex sizes are invalid as a min sizing function. However we still can have a flexible |minTrackBreadth|
// if the track size is just a flex size (e.g. "1fr"), the spec says that in this case it implies an automatic minimum.
if (minTrackBreadth.isFlex())
minTrackBreadth = Length(LengthType::Auto);
return GridTrackSize(minTrackBreadth, maxTrackBreadth);
}
double GridTrackSizingAlgorithm::computeFlexFactorUnitSize(const Vector<GridTrack>& tracks, double flexFactorSum, LayoutUnit& leftOverSpace, const Vector<unsigned, 8>& flexibleTracksIndexes, std::unique_ptr<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".
bool validFlexFactorUnit = true;
for (auto index : flexibleTracksIndexes) {
if (tracksToTreatAsInflexible && tracksToTreatAsInflexible->contains(index))
continue;
LayoutUnit baseSize = tracks[index].baseSize();
double flexFactor = tracks[index].cachedTrackSize().maxTrackBreadth().flex();
// treating all such tracks as inflexible.
if (baseSize > hypotheticalFactorUnitSize * flexFactor) {
leftOverSpace -= baseSize;
flexFactorSum -= flexFactor;
if (!tracksToTreatAsInflexible)
tracksToTreatAsInflexible = makeUnique<TrackIndexSet>();
tracksToTreatAsInflexible->add(index);
validFlexFactorUnit = false;
}
}
if (!validFlexFactorUnit)
return computeFlexFactorUnitSize(tracks, flexFactorSum, leftOverSpace, flexibleTracksIndexes, WTFMove(tracksToTreatAsInflexible));
return hypotheticalFactorUnitSize;
}
void GridTrackSizingAlgorithm::computeFlexSizedTracksGrowth(double flexFraction, Vector<LayoutUnit>& increments, LayoutUnit& totalGrowth) const
{
size_t numFlexTracks = m_flexibleSizedTracksIndex.size();
ASSERT(increments.size() == numFlexTracks);
const Vector<GridTrack>& allTracks = tracks(m_direction);
// The flexFraction multiplied by the flex factor can result in a non-integer size. Since we floor the stretched size to fit in a LayoutUnit,
// we may lose the fractional part of the computation which can cause the entire free space not being distributed evenly. The leftover
// fractional part from every flexible track are accumulated here to avoid this issue.
double leftOverSize = 0;
for (size_t i = 0; i < numFlexTracks; ++i) {
unsigned trackIndex = m_flexibleSizedTracksIndex[i];
const auto& trackSize = allTracks[trackIndex].cachedTrackSize();
ASSERT(trackSize.maxTrackBreadth().isFlex());
LayoutUnit oldBaseSize = allTracks[trackIndex].baseSize();
double frShare = flexFraction * trackSize.maxTrackBreadth().flex() + leftOverSize;
auto stretchedSize = LayoutUnit(frShare);
LayoutUnit newBaseSize = std::max(oldBaseSize, stretchedSize);
increments[i] = newBaseSize - oldBaseSize;
totalGrowth += increments[i];
// In the case that stretchedSize is greater than frShare, we floor it to 0 to avoid a negative leftover.
leftOverSize = std::max(frShare - stretchedSize.toDouble(), 0.0);
}
}
double GridTrackSizingAlgorithm::findFrUnitSize(const GridSpan& tracksSpan, LayoutUnit leftOverSpace) const
{
if (leftOverSpace <= 0)
return 0;
const Vector<GridTrack>& allTracks = tracks(m_direction);
double flexFactorSum = 0;
Vector<unsigned, 8> flexibleTracksIndexes;
for (auto trackIndex : tracksSpan) {
const auto& trackSize = allTracks[trackIndex].cachedTrackSize();
if (!trackSize.maxTrackBreadth().isFlex())
leftOverSpace -= allTracks[trackIndex].baseSize();
else {
double flexFactor = trackSize.maxTrackBreadth().flex();
flexibleTracksIndexes.append(trackIndex);
flexFactorSum += flexFactor;
}
}
// We don't remove the gutters from left_over_space here, because that was already done before.
// The function is not called if we don't have <flex> grid tracks.
ASSERT(!flexibleTracksIndexes.isEmpty());
return computeFlexFactorUnitSize(allTracks, flexFactorSum, leftOverSpace, flexibleTracksIndexes);
}
void GridTrackSizingAlgorithm::computeGridContainerIntrinsicSizes()
{
m_minContentSize = m_maxContentSize = 0_lu;
Vector<GridTrack>& allTracks = tracks(m_direction);
for (auto& track : allTracks) {
ASSERT(m_strategy->isComputingSizeContainment() || m_strategy->isComputingInlineSizeContainment() || !track.infiniteGrowthPotential());
m_minContentSize += track.baseSize();
m_maxContentSize += track.growthLimitIsInfinite() ? track.baseSize() : track.growthLimit();
// The growth limit caps must be cleared now in order to properly sort
// tracks by growth potential on an eventual "Maximize Tracks".
track.setGrowthLimitCap(std::nullopt);
}
}
// GridTrackSizingAlgorithmStrategy.
LayoutUnit GridTrackSizingAlgorithmStrategy::logicalHeightForChild(RenderBox& child) const
{
GridTrackSizingDirection childBlockDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForRows);
// 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 block-axis override size to nullopt (no possible resolution).
if (shouldClearOverridingContainingBlockContentSizeForChild(child, ForRows)) {
setOverridingContainingBlockContentSizeForChild(*renderGrid(), child, childBlockDirection, std::nullopt);
child.setNeedsLayout(MarkOnlyThis);
}
// We need to clear the stretched height to properly compute logical height during layout.
if (child.needsLayout())
child.clearOverridingLogicalHeight();
child.layoutIfNeeded();
return child.logicalHeight() + GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), childBlockDirection, child) + m_algorithm.baselineOffsetForChild(child, gridAxisForDirection(direction()));
}
LayoutUnit GridTrackSizingAlgorithmStrategy::minContentForChild(RenderBox& child) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
if (direction() == childInlineDirection) {
if (isComputingInlineSizeContainment())
return { };
// 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
if (child.needsPreferredWidthsRecalculation())
child.setPreferredLogicalWidthsDirty(true);
return child.minPreferredLogicalWidth() + GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), childInlineDirection, child) + m_algorithm.baselineOffsetForChild(child, gridAxisForDirection(direction()));
}
if (updateOverridingContainingBlockContentSizeForChild(child, childInlineDirection)) {
child.setNeedsLayout(MarkOnlyThis);
// For a child with relative width constraints to the grid area, such as percentaged paddings, we reset the overridingContainingBlockContentSizeForChild value for columns when we are executing a definite strategy
// for columns. Since we have updated the overridingContainingBlockContentSizeForChild inline-axis/width value here, we might need to recompute the child's relative width. For some cases, we probably will not
// be able to do it during the RenderGrid::layoutGridItems() function as the grid area does't change there any more. Also, as we are doing a layout inside GridTrackSizingAlgorithmStrategy::logicalHeightForChild()
// function, let's take the advantage and set it here.
if (shouldClearOverridingContainingBlockContentSizeForChild(child, childInlineDirection))
child.setPreferredLogicalWidthsDirty(true);
}
return logicalHeightForChild(child);
}
LayoutUnit GridTrackSizingAlgorithmStrategy::maxContentForChild(RenderBox& child) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
if (direction() == childInlineDirection) {
if (isComputingInlineSizeContainment())
return { };
// 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
if (child.needsPreferredWidthsRecalculation())
child.setPreferredLogicalWidthsDirty(true);
return child.maxPreferredLogicalWidth() + GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), childInlineDirection, child) + m_algorithm.baselineOffsetForChild(child, gridAxisForDirection(direction()));
}
if (updateOverridingContainingBlockContentSizeForChild(child, childInlineDirection))
child.setNeedsLayout(MarkOnlyThis);
return logicalHeightForChild(child);
}
LayoutUnit GridTrackSizingAlgorithmStrategy::minSizeForChild(RenderBox& child) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
bool isRowAxis = direction() == childInlineDirection;
if (isRowAxis && isComputingInlineSizeContainment())
return { };
const Length& childSize = isRowAxis ? child.style().logicalWidth() : child.style().logicalHeight();
if (!childSize.isAuto() && !childSize.isPercentOrCalculated())
return minContentForChild(child);
const Length& childMinSize = isRowAxis ? child.style().logicalMinWidth() : child.style().logicalMinHeight();
bool overflowIsVisible = isRowAxis ? child.effectiveOverflowInlineDirection() == Overflow::Visible : child.effectiveOverflowBlockDirection() == Overflow::Visible;
LayoutUnit baselineShim = m_algorithm.baselineOffsetForChild(child, gridAxisForDirection(direction()));
if (childMinSize.isAuto() && overflowIsVisible) {
auto minSize = minContentForChild(child);
const GridSpan& span = m_algorithm.m_renderGrid->gridSpanForChild(child, direction());
LayoutUnit maxBreadth;
auto allTracks = m_algorithm.tracks(direction());
bool allFixed = true;
for (auto trackPosition : span) {
const auto& trackSize = allTracks[trackPosition].cachedTrackSize();
if (trackSize.maxTrackBreadth().isFlex() && span.integerSpan() > 1)
return { };
if (!trackSize.hasFixedMaxTrackBreadth())
allFixed = false;
else if (allFixed)
maxBreadth += valueForLength(trackSize.maxTrackBreadth().length(), availableSpace().value_or(0_lu));
}
if (!allFixed)
return minSize;
if (minSize > maxBreadth) {
auto marginAndBorderAndPadding = GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), direction(), child);
marginAndBorderAndPadding += isRowAxis ? child.borderAndPaddingLogicalWidth() : child.borderAndPaddingLogicalHeight();
minSize = std::max(maxBreadth, marginAndBorderAndPadding + baselineShim);
}
return minSize;
}
std::optional<LayoutUnit> gridAreaSize = m_algorithm.gridAreaBreadthForChild(child, childInlineDirection);
return minLogicalSizeForChild(child, childMinSize, gridAreaSize) + baselineShim;
}
bool GridTrackSizingAlgorithm::canParticipateInBaselineAlignment(const RenderBox& child, GridAxis baselineAxis) const
{
ASSERT(baselineAxis == GridColumnAxis ? m_columnBaselineItemsMap.contains(&child) : m_rowBaselineItemsMap.contains(&child));
// Baseline cyclic dependencies only happen with synthesized
// baselines. These cases include orthogonal or empty grid items
// and replaced elements.
bool isParallelToBaselineAxis = baselineAxis == GridColumnAxis ? !GridLayoutFunctions::isOrthogonalChild(*m_renderGrid, child) : GridLayoutFunctions::isOrthogonalChild(*m_renderGrid, child);
if (isParallelToBaselineAxis && child.firstLineBaseline())
return true;
// FIXME: We don't currently allow items within subgrids that need to
// synthesize a baseline, since we need a layout to have been completed
// and performGridItemsPreLayout on the outer grid doesn't layout subgrid
// items.
if (child.parent() != renderGrid())
return false;
// Baseline cyclic dependencies only happen in grid areas with
// intrinsically-sized tracks.
if (!isIntrinsicSizedGridArea(child, baselineAxis))
return true;
return isParallelToBaselineAxis ? !child.hasRelativeLogicalHeight() : !child.hasRelativeLogicalWidth() && !child.style().logicalWidth().isAuto();
}
bool GridTrackSizingAlgorithm::participateInBaselineAlignment(const RenderBox& child, GridAxis baselineAxis) const
{
return baselineAxis == GridColumnAxis ? m_columnBaselineItemsMap.get(&child) : m_rowBaselineItemsMap.get(&child);
}
void GridTrackSizingAlgorithm::updateBaselineAlignmentContext(const RenderBox& child, GridAxis baselineAxis)
{
ASSERT(wasSetup());
ASSERT(canParticipateInBaselineAlignment(child, baselineAxis));
ItemPosition align = m_renderGrid->selfAlignmentForChild(baselineAxis, child).position();
const auto& span = m_renderGrid->gridSpanForChild(child, gridDirectionForAxis(baselineAxis));
m_baselineAlignment.updateBaselineAlignmentContext(align, span.startLine(), child, baselineAxis);
}
LayoutUnit GridTrackSizingAlgorithm::baselineOffsetForChild(const RenderBox& child, GridAxis baselineAxis) const
{
// If we haven't yet initialized this axis (which can be the case if we're doing
// prelayout of a subgrid), then we can't know the baseline offset.
if (tracks(gridDirectionForAxis(baselineAxis)).isEmpty())
return LayoutUnit();
if (!participateInBaselineAlignment(child, baselineAxis))
return LayoutUnit();
ItemPosition align = m_renderGrid->selfAlignmentForChild(baselineAxis, child).position();
const auto& span = m_renderGrid->gridSpanForChild(child, gridDirectionForAxis(baselineAxis));
return m_baselineAlignment.baselineOffsetForChild(align, span.startLine(), child, baselineAxis);
}
void GridTrackSizingAlgorithm::clearBaselineItemsCache()
{
m_columnBaselineItemsMap.clear();
m_rowBaselineItemsMap.clear();
}
void GridTrackSizingAlgorithm::cacheBaselineAlignedItem(const RenderBox& item, GridAxis axis)
{
ASSERT(downcast<RenderGrid>(item.parent())->isBaselineAlignmentForChild(item, axis));
if (GridLayoutFunctions::isOrthogonalParent(*m_renderGrid, *item.parent()))
axis = axis == GridColumnAxis ? GridRowAxis : GridColumnAxis;
if (axis == GridColumnAxis)
m_columnBaselineItemsMap.add(&item, true);
else
m_rowBaselineItemsMap.add(&item, true);
}
void GridTrackSizingAlgorithm::copyBaselineItemsCache(const GridTrackSizingAlgorithm& source, GridAxis axis)
{
if (axis == GridColumnAxis)
m_columnBaselineItemsMap = source.m_columnBaselineItemsMap;
else
m_rowBaselineItemsMap = source.m_rowBaselineItemsMap;
}
bool GridTrackSizingAlgorithmStrategy::updateOverridingContainingBlockContentSizeForChild(RenderBox& child, GridTrackSizingDirection direction, std::optional<LayoutUnit> overrideSize) const
{
if (!overrideSize)
overrideSize = m_algorithm.gridAreaBreadthForChild(child, direction);
if (renderGrid() != child.parent()) {
// If child is part of a subgrid, find the nearest ancestor this is directly part of this grid
// (either by being a child of the grid, or via being subgridded in this dimension.
RenderGrid* grid = downcast<RenderGrid>(child.parent());
GridTrackSizingDirection subgridDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), *grid, direction);
while (grid->parent() != renderGrid() && !grid->isSubgridOf(subgridDirection, *renderGrid())) {
grid = downcast<RenderGrid>(grid->parent());
subgridDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), *grid, direction);
}
if (grid == child.parent() && grid->isSubgrid(subgridDirection)) {
// If the item is subgridded in this direction (and thus the tracks it covers are tracks
// owned by this sizing algorithm), then we want to take the breadth of the tracks we occupy,
// and subtract any space occupied by the subgrid itself (and any ancestor subgrids).
*overrideSize -= GridLayoutFunctions::extraMarginForSubgridAncestors(subgridDirection, child);
} else {
// Otherwise the tracks that this child covers (in this non-subgridded axis) are owned
// by one of the intermediate RenderGrids (which are subgrids in the other axis), which may
// be |grid| or a descendent.
// Set the override size for |grid| (which is part of the outer grid), and force a layout
// so that it computes the track sizes for the non-subgridded dimension and makes the size
// of |child| available.
bool overrideSizeHasChanged =
updateOverridingContainingBlockContentSizeForChild(*grid, direction);
layoutGridItemForMinSizeComputation(*grid, overrideSizeHasChanged);
return overrideSizeHasChanged;
}
}
if (GridLayoutFunctions::hasOverridingContainingBlockContentSizeForChild(child, direction) && GridLayoutFunctions::overridingContainingBlockContentSizeForChild(child, direction) == overrideSize)
return false;
setOverridingContainingBlockContentSizeForChild(*renderGrid(), child, direction, overrideSize);
return true;
}
LayoutUnit GridTrackSizingAlgorithmStrategy::minLogicalSizeForChild(RenderBox& child, const Length& childMinSize, std::optional<LayoutUnit> availableSize) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
bool isRowAxis = direction() == childInlineDirection;
if (isRowAxis)
return isComputingInlineSizeContainment() ? 0_lu : child.computeLogicalWidthInFragmentUsing(MinSize, childMinSize, availableSize.value_or(0), *renderGrid(), nullptr) + GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), childInlineDirection, child);
bool overrideSizeHasChanged = updateOverridingContainingBlockContentSizeForChild(child, childInlineDirection, availableSize);
layoutGridItemForMinSizeComputation(child, overrideSizeHasChanged);
GridTrackSizingDirection childBlockDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForRows);
return child.computeLogicalHeightUsing(MinSize, childMinSize, std::nullopt).value_or(0) + GridLayoutFunctions::marginLogicalSizeForChild(*renderGrid(), childBlockDirection, child);
}
class IndefiniteSizeStrategy final : public GridTrackSizingAlgorithmStrategy {
public:
IndefiniteSizeStrategy(GridTrackSizingAlgorithm& algorithm)
: GridTrackSizingAlgorithmStrategy(algorithm) { }
private:
void layoutGridItemForMinSizeComputation(RenderBox&, bool overrideSizeHasChanged) const override;
void maximizeTracks(Vector<GridTrack>&, std::optional<LayoutUnit>& freeSpace) override;
double findUsedFlexFraction(Vector<unsigned>& flexibleSizedTracksIndex, GridTrackSizingDirection, std::optional<LayoutUnit> freeSpace) const override;
bool recomputeUsedFlexFractionIfNeeded(double& flexFraction, LayoutUnit& totalGrowth) const override;
LayoutUnit freeSpaceForStretchAutoTracksStep() const override;
bool isComputingSizeContainment() const override { return renderGrid()->shouldApplySizeContainment(); }
bool isComputingInlineSizeContainment() const override { return renderGrid()->shouldApplyInlineSizeContainment(); }
void accumulateFlexFraction(double& flexFraction, GridIterator&, GridTrackSizingDirection outermostDirection, HashSet<RenderBox*>& itemsSet) const;
};
void IndefiniteSizeStrategy::layoutGridItemForMinSizeComputation(RenderBox& child, bool overrideSizeHasChanged) const
{
if (overrideSizeHasChanged && direction() != ForColumns)
child.setNeedsLayout(MarkOnlyThis);
child.layoutIfNeeded();
}
void IndefiniteSizeStrategy::maximizeTracks(Vector<GridTrack>& tracks, std::optional<LayoutUnit>& freeSpace)
{
UNUSED_PARAM(freeSpace);
for (auto& track : tracks)
track.setBaseSize(track.growthLimit());
}
static inline double normalizedFlexFraction(const GridTrack& track)
{
double flexFactor = track.cachedTrackSize().maxTrackBreadth().flex();
return track.baseSize() / std::max<double>(1, flexFactor);
}
void IndefiniteSizeStrategy::accumulateFlexFraction(double& flexFraction, GridIterator& iterator, GridTrackSizingDirection outermostDirection, HashSet<RenderBox*>& itemsSet) const
{
while (auto* gridItem = iterator.nextGridItem()) {
if (is<RenderGrid>(gridItem) && downcast<RenderGrid>(gridItem)->isSubgridInParentDirection(iterator.direction())) {
RenderGrid* inner = downcast<RenderGrid>(gridItem);
GridIterator childIterator = GridIterator::createForSubgrid(*inner, iterator);
accumulateFlexFraction(flexFraction, childIterator, outermostDirection, itemsSet);
continue;
}
// Do not include already processed items.
if (!itemsSet.add(gridItem).isNewEntry)
continue;
GridSpan span = m_algorithm.renderGrid()->gridSpanForChild(*gridItem, outermostDirection);
// Removing gutters from the max-content contribution of the item, so they are not taken into account in FindFrUnitSize().
LayoutUnit leftOverSpace = maxContentForChild(*gridItem) - renderGrid()->guttersSize(m_algorithm.grid(), outermostDirection, span.startLine(), span.integerSpan(), availableSpace());
flexFraction = std::max(flexFraction, findFrUnitSize(span, leftOverSpace));
}
}
double IndefiniteSizeStrategy::findUsedFlexFraction(Vector<unsigned>& flexibleSizedTracksIndex, GridTrackSizingDirection direction, std::optional<LayoutUnit> freeSpace) const
{
UNUSED_PARAM(freeSpace);
auto allTracks = m_algorithm.tracks(direction);
double flexFraction = 0;
for (const auto& trackIndex : flexibleSizedTracksIndex) {
// FIXME: we pass TrackSizing to gridTrackSize() because it does not really matter
// as we know the track is a flex sized track. It'd be nice not to have to do that.
flexFraction = std::max(flexFraction, normalizedFlexFraction(allTracks[trackIndex]));
}
const Grid& grid = m_algorithm.grid();
if (!grid.hasGridItems())
return flexFraction;
HashSet<RenderBox*> itemsSet;
for (const auto& trackIndex : flexibleSizedTracksIndex) {
GridIterator iterator(grid, direction, trackIndex);
accumulateFlexFraction(flexFraction, iterator, direction, itemsSet);
}
return flexFraction;
}
bool IndefiniteSizeStrategy::recomputeUsedFlexFractionIfNeeded(double& flexFraction, LayoutUnit& totalGrowth) const
{
if (direction() == ForColumns)
return false;
const RenderGrid* renderGrid = this->renderGrid();
auto minSize = renderGrid->computeContentLogicalHeight(MinSize, renderGrid->style().logicalMinHeight(), std::nullopt);
auto maxSize = renderGrid->computeContentLogicalHeight(MaxSize, renderGrid->style().logicalMaxHeight(), std::nullopt);
// Redo the flex fraction computation using min|max-height as definite available space in case
// the total height is smaller than min-height or larger than max-height.
LayoutUnit rowsSize = totalGrowth + computeTrackBasedSize();
bool checkMinSize = minSize && rowsSize < minSize.value();
bool checkMaxSize = maxSize && rowsSize > maxSize.value();
if (!checkMinSize && !checkMaxSize)
return false;
LayoutUnit freeSpace = checkMaxSize ? maxSize.value() : -1_lu;
const Grid& grid = m_algorithm.grid();
freeSpace = std::max(freeSpace, minSize.value_or(0_lu)) - renderGrid->guttersSize(grid, ForRows, 0, grid.numTracks(ForRows), availableSpace());
size_t numberOfTracks = m_algorithm.tracks(ForRows).size();
flexFraction = findFrUnitSize(GridSpan::translatedDefiniteGridSpan(0, numberOfTracks), freeSpace);
return true;
}
class DefiniteSizeStrategy final : public GridTrackSizingAlgorithmStrategy {
public:
DefiniteSizeStrategy(GridTrackSizingAlgorithm& algorithm)
: GridTrackSizingAlgorithmStrategy(algorithm) { }
private:
void layoutGridItemForMinSizeComputation(RenderBox&, bool overrideSizeHasChanged) const override;
void maximizeTracks(Vector<GridTrack>&, std::optional<LayoutUnit>& freeSpace) override;
double findUsedFlexFraction(Vector<unsigned>& flexibleSizedTracksIndex, GridTrackSizingDirection, std::optional<LayoutUnit> freeSpace) const override;
bool recomputeUsedFlexFractionIfNeeded(double& flexFraction, LayoutUnit& totalGrowth) const override;
LayoutUnit freeSpaceForStretchAutoTracksStep() const override;
LayoutUnit minContentForChild(RenderBox&) const override;
LayoutUnit minLogicalSizeForChild(RenderBox&, const Length& childMinSize, std::optional<LayoutUnit> availableSize) const override;
bool isComputingSizeContainment() const override { return false; }
bool isComputingInlineSizeContainment() const override { return false; }
};
LayoutUnit IndefiniteSizeStrategy::freeSpaceForStretchAutoTracksStep() const
{
ASSERT(!m_algorithm.freeSpace(direction()));
if (direction() == ForColumns)
return 0_lu;
auto minSize = renderGrid()->computeContentLogicalHeight(MinSize, renderGrid()->style().logicalMinHeight(), std::nullopt);
if (!minSize)
return 0_lu;
return minSize.value() - computeTrackBasedSize();
}
LayoutUnit DefiniteSizeStrategy::minLogicalSizeForChild(RenderBox& child, const Length& childMinSize, std::optional<LayoutUnit> availableSize) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
GridTrackSizingDirection flowAwareDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, direction());
if (hasRelativeMarginOrPaddingForChild(child, flowAwareDirection) || (direction() != childInlineDirection && hasRelativeOrIntrinsicSizeForChild(child, flowAwareDirection))) {
auto indefiniteSize = direction() == childInlineDirection ? std::make_optional(0_lu) : std::nullopt;
setOverridingContainingBlockContentSizeForChild(*renderGrid(), child, direction(), indefiniteSize);
}
return GridTrackSizingAlgorithmStrategy::minLogicalSizeForChild(child, childMinSize, availableSize);
}
void DefiniteSizeStrategy::maximizeTracks(Vector<GridTrack>& tracks, std::optional<LayoutUnit>& freeSpace)
{
size_t tracksSize = tracks.size();
Vector<GridTrack*> tracksForDistribution(tracksSize);
for (size_t i = 0; i < tracksSize; ++i) {
tracksForDistribution[i] = tracks.data() + i;
tracksForDistribution[i]->setPlannedSize(tracksForDistribution[i]->baseSize());
}
ASSERT(freeSpace);
distributeSpaceToTracks(tracksForDistribution, freeSpace.value());
for (auto* track : tracksForDistribution)
track->setBaseSize(track->plannedSize());
}
void DefiniteSizeStrategy::layoutGridItemForMinSizeComputation(RenderBox& child, bool overrideSizeHasChanged) const
{
if (overrideSizeHasChanged)
child.setNeedsLayout(MarkOnlyThis);
child.layoutIfNeeded();
}
double DefiniteSizeStrategy::findUsedFlexFraction(Vector<unsigned>&, GridTrackSizingDirection direction, std::optional<LayoutUnit> freeSpace) const
{
GridSpan allTracksSpan = GridSpan::translatedDefiniteGridSpan(0, m_algorithm.tracks(direction).size());
ASSERT(freeSpace);
return findFrUnitSize(allTracksSpan, freeSpace.value());
}
LayoutUnit DefiniteSizeStrategy::freeSpaceForStretchAutoTracksStep() const
{
return m_algorithm.freeSpace(direction()).value();
}
LayoutUnit DefiniteSizeStrategy::minContentForChild(RenderBox& child) const
{
GridTrackSizingDirection childInlineDirection = GridLayoutFunctions::flowAwareDirectionForChild(*renderGrid(), child, ForColumns);
if (direction() == childInlineDirection && child.needsLayout() && shouldClearOverridingContainingBlockContentSizeForChild(child, ForColumns))
setOverridingContainingBlockContentSizeForChild(*renderGrid(), child, childInlineDirection, LayoutUnit());
return GridTrackSizingAlgorithmStrategy::minContentForChild(child);
}
bool DefiniteSizeStrategy::recomputeUsedFlexFractionIfNeeded(double& flexFraction, LayoutUnit& totalGrowth) const
{
UNUSED_PARAM(flexFraction);
UNUSED_PARAM(totalGrowth);
return false;
}
// GridTrackSizingAlgorithm steps.
void GridTrackSizingAlgorithm::initializeTrackSizes()
{
ASSERT(m_contentSizedTracksIndex.isEmpty());
ASSERT(m_flexibleSizedTracksIndex.isEmpty());
ASSERT(m_autoSizedTracksForStretchIndex.isEmpty());
ASSERT(!m_hasPercentSizedRowsIndefiniteHeight);
ASSERT(!m_hasFlexibleMaxTrackBreadth);
Vector<GridTrack>& allTracks = tracks(m_direction);
const bool indefiniteHeight = m_direction == ForRows && !m_renderGrid->hasDefiniteLogicalHeight();
LayoutUnit maxSize = std::max(0_lu, availableSpace().value_or(0_lu));
// 1. Initialize per Grid track variables.
for (unsigned i = 0; i < allTracks.size(); ++i) {
GridTrack& track = allTracks[i];
const auto& trackSize = calculateGridTrackSize(m_direction, i);
track.setCachedTrackSize(trackSize);
track.setBaseSize(initialBaseSize(trackSize));
track.setGrowthLimit(initialGrowthLimit(trackSize, track.baseSize()));
track.setInfinitelyGrowable(false);
if (trackSize.isFitContent())
track.setGrowthLimitCap(valueForLength(trackSize.fitContentTrackBreadth().length(), maxSize));
if (trackSize.isContentSized())
m_contentSizedTracksIndex.append(i);
if (trackSize.maxTrackBreadth().isFlex())
m_flexibleSizedTracksIndex.append(i);
if (trackSize.hasAutoMaxTrackBreadth() && !trackSize.isFitContent())
m_autoSizedTracksForStretchIndex.append(i);
if (indefiniteHeight) {
auto& rawTrackSize = rawGridTrackSize(m_direction, i);
// Set the flag for repeating the track sizing algorithm. For flexible tracks, as per spec https://drafts.csswg.org/css-grid/#algo-flex-tracks,
// in clause "if the free space is an indefinite length:", it states that "If using this flex fraction would cause the grid to be smaller than
// the grid container’s min-width/height (or larger than the grid container’s max-width/height), then redo this step".
if (!m_hasFlexibleMaxTrackBreadth && rawTrackSize.maxTrackBreadth().isFlex())
m_hasFlexibleMaxTrackBreadth = true;
if (!m_hasPercentSizedRowsIndefiniteHeight && (rawTrackSize.minTrackBreadth().isPercentage() || rawTrackSize.maxTrackBreadth().isPercentage()))
m_hasPercentSizedRowsIndefiniteHeight = true;
}
}
}
static LayoutUnit marginAndBorderAndPaddingForEdge(const RenderGrid& grid, GridTrackSizingDirection direction, bool startEdge)
{
if (direction == ForColumns)
return startEdge ? grid.marginAndBorderAndPaddingStart() : grid.marginAndBorderAndPaddingEnd();
return startEdge ? grid.marginAndBorderAndPaddingBefore() : grid.marginAndBorderAndPaddingAfter();
}
// https://drafts.csswg.org/css-grid-2/#subgrid-edge-placeholders
// FIXME: This is a simplification of the specified behaviour, where we add the hypothetical
// items directly to the edge tracks as if they had a span of 1. This matches the current Gecko
// behavior.
static void addSubgridMarginBorderPadding(const RenderGrid* outermost, GridTrackSizingDirection outermostDirection, Vector<GridTrack>& allTracks, GridSpan& span, RenderGrid* subgrid)
{
// Convert the direction into the coordinate space of subgrid (which may not be a direct child
// of the outermost grid for which we're running the track sizing algorithm).
GridTrackSizingDirection direction = GridLayoutFunctions::flowAwareDirectionForChild(*outermost, *subgrid, outermostDirection);
bool reversed = GridLayoutFunctions::isSubgridReversedDirection(*outermost, outermostDirection, *subgrid);
if (allTracks[span.startLine()].cachedTrackSize().hasIntrinsicMinTrackBreadth()) {
// If the subgrid has a reversed flow direction relative to the outermost grid, then
// we want the MBP from the end edge in its local coordinate space.
LayoutUnit mbpStart = marginAndBorderAndPaddingForEdge(*subgrid, direction, !reversed);
allTracks[span.startLine()].setBaseSize(std::max(allTracks[span.startLine()].baseSize(), mbpStart));
}
if (allTracks[span.endLine() - 1].cachedTrackSize().hasIntrinsicMinTrackBreadth()) {
LayoutUnit mbpEnd = marginAndBorderAndPaddingForEdge(*subgrid, direction, reversed);
allTracks[span.endLine() - 1].setBaseSize(std::max(allTracks[span.endLine() - 1].baseSize(), mbpEnd));
}
}
void GridTrackSizingAlgorithm::accumulateIntrinsicSizesForTrack(GridTrack& track, GridIterator& iterator, Vector<GridItemWithSpan>& itemsSortedByIncreasingSpan, Vector<GridItemWithSpan>& itemsCrossingFlexibleTracks, HashSet<RenderBox*>& itemsSet)
{
Vector<GridTrack>& allTracks = tracks(m_direction);
while (auto* gridItem = iterator.nextGridItem()) {
bool isNewEntry = itemsSet.add(gridItem).isNewEntry;
if (is<RenderGrid>(gridItem) && downcast<RenderGrid>(gridItem)->isSubgridInParentDirection(iterator.direction())) {
// Contribute the mbp of wrapper to the first and last tracks that we span.
RenderGrid* inner = downcast<RenderGrid>(gridItem);
if (isNewEntry) {
GridSpan span = m_renderGrid->gridSpanForChild(*gridItem, m_direction);
addSubgridMarginBorderPadding(m_renderGrid, m_direction, allTracks, span, inner);
}
GridIterator childIterator = GridIterator::createForSubgrid(*inner, iterator);
accumulateIntrinsicSizesForTrack(track, childIterator, itemsSortedByIncreasingSpan, itemsCrossingFlexibleTracks, itemsSet);
continue;
}
if (!isNewEntry)
continue;
GridSpan span = m_renderGrid->gridSpanForChild(*gridItem, m_direction);
if (spanningItemCrossesFlexibleSizedTracks(span))
itemsCrossingFlexibleTracks.append(GridItemWithSpan(*gridItem, span));
else if (span.integerSpan() == 1)
sizeTrackToFitNonSpanningItem(span, *gridItem, track);
else
itemsSortedByIncreasingSpan.append(GridItemWithSpan(*gridItem, span));
}
}
void GridTrackSizingAlgorithm::resolveIntrinsicTrackSizes()
{
Vector<GridTrack>& allTracks = tracks(m_direction);
auto handleInfinityGrowthLimit = [&]() {
for (auto trackIndex : m_contentSizedTracksIndex) {
GridTrack& track = allTracks[trackIndex];
if (track.growthLimit() == infinity)
track.setGrowthLimit(track.baseSize());
}
};
if (m_strategy->isComputingSizeContainment()) {
handleInfinityGrowthLimit();
return;
}
Vector<GridItemWithSpan> itemsSortedByIncreasingSpan;
Vector<GridItemWithSpan> itemsCrossingFlexibleTracks;
HashSet<RenderBox*> itemsSet;
if (m_grid.hasGridItems()) {
for (auto trackIndex : m_contentSizedTracksIndex) {
GridIterator iterator(m_grid, m_direction, trackIndex);
GridTrack& track = allTracks[trackIndex];
accumulateIntrinsicSizesForTrack(track, iterator, itemsSortedByIncreasingSpan, itemsCrossingFlexibleTracks, itemsSet);
}
std::sort(itemsSortedByIncreasingSpan.begin(), itemsSortedByIncreasingSpan.end());
}
auto it = itemsSortedByIncreasingSpan.begin();
auto end = itemsSortedByIncreasingSpan.end();
while (it != end) {
GridItemsSpanGroupRange spanGroupRange = { it, std::upper_bound(it, end, *it) };
increaseSizesToAccommodateSpanningItems<TrackSizeComputationVariant::NotCrossingFlexibleTracks>(spanGroupRange);
it = spanGroupRange.rangeEnd;
}
GridItemsSpanGroupRange tracksGroupRange = { itemsCrossingFlexibleTracks.begin(), itemsCrossingFlexibleTracks.end() };
increaseSizesToAccommodateSpanningItems<TrackSizeComputationVariant::CrossingFlexibleTracks>(tracksGroupRange);
handleInfinityGrowthLimit();
}
void GridTrackSizingAlgorithm::stretchFlexibleTracks(std::optional<LayoutUnit> freeSpace)
{
if (m_flexibleSizedTracksIndex.isEmpty())
return;
double flexFraction = m_strategy->findUsedFlexFraction(m_flexibleSizedTracksIndex, m_direction, freeSpace);
LayoutUnit totalGrowth;
Vector<LayoutUnit> increments;
increments.grow(m_flexibleSizedTracksIndex.size());
computeFlexSizedTracksGrowth(flexFraction, increments, totalGrowth);
if (m_strategy->recomputeUsedFlexFractionIfNeeded(flexFraction, totalGrowth)) {
totalGrowth = 0_lu;
computeFlexSizedTracksGrowth(flexFraction, increments, totalGrowth);
}
size_t i = 0;
Vector<GridTrack>& allTracks = tracks(m_direction);
for (auto trackIndex : m_flexibleSizedTracksIndex) {
auto& track = allTracks[trackIndex];
if (LayoutUnit increment = increments[i++])
track.setBaseSize(track.baseSize() + increment);
}
if (this->freeSpace(m_direction))
setFreeSpace(m_direction, this->freeSpace(m_direction).value() - totalGrowth);
m_maxContentSize += totalGrowth;
}
void GridTrackSizingAlgorithm::stretchAutoTracks()
{
auto currentFreeSpace = m_strategy->freeSpaceForStretchAutoTracksStep();
if (m_autoSizedTracksForStretchIndex.isEmpty() || currentFreeSpace <= 0
|| (m_renderGrid->contentAlignment(m_direction).distribution() != ContentDistribution::Stretch))
return;
Vector<GridTrack>& allTracks = tracks(m_direction);
unsigned numberOfAutoSizedTracks = m_autoSizedTracksForStretchIndex.size();
LayoutUnit sizeToIncrease = currentFreeSpace / numberOfAutoSizedTracks;
for (const auto& trackIndex : m_autoSizedTracksForStretchIndex) {
auto& track = allTracks[trackIndex];
track.setBaseSize(track.baseSize() + sizeToIncrease);
}
setFreeSpace(m_direction, 0_lu);
}
void GridTrackSizingAlgorithm::advanceNextState()
{
switch (m_sizingState) {
case ColumnSizingFirstIteration:
m_sizingState = m_strategy->isComputingSizeContainment() || m_strategy->isComputingInlineSizeContainment() ? ColumnSizingExtraIterationForSizeContainment : RowSizingFirstIteration;
return;
case ColumnSizingExtraIterationForSizeContainment:
m_sizingState = RowSizingFirstIteration;
return;
case RowSizingFirstIteration:
m_sizingState = m_strategy->isComputingSizeContainment() ? RowSizingExtraIterationForSizeContainment : ColumnSizingSecondIteration;
return;
case RowSizingExtraIterationForSizeContainment:
m_sizingState = ColumnSizingSecondIteration;
return;
case ColumnSizingSecondIteration:
m_sizingState = RowSizingSecondIteration;
return;
case RowSizingSecondIteration:
m_sizingState = ColumnSizingFirstIteration;
return;
}
ASSERT_NOT_REACHED();
m_sizingState = ColumnSizingFirstIteration;
}
bool GridTrackSizingAlgorithm::isValidTransition() const
{
switch (m_sizingState) {
case ColumnSizingFirstIteration:
case ColumnSizingExtraIterationForSizeContainment:
case ColumnSizingSecondIteration:
return m_direction == ForColumns;
case RowSizingFirstIteration:
case RowSizingExtraIterationForSizeContainment:
case RowSizingSecondIteration:
return m_direction == ForRows;
}
ASSERT_NOT_REACHED();
return false;
}
// GridTrackSizingAlgorithm API.
void GridTrackSizingAlgorithm::setup(GridTrackSizingDirection direction, unsigned numTracks, SizingOperation sizingOperation, std::optional<LayoutUnit> availableSpace)
{
ASSERT(m_needsSetup);
m_direction = direction;
setAvailableSpace(direction, availableSpace ? std::max(0_lu, *availableSpace) : availableSpace);
m_sizingOperation = sizingOperation;
switch (m_sizingOperation) {
case IntrinsicSizeComputation:
m_strategy = makeUnique<IndefiniteSizeStrategy>(*this);
break;
case TrackSizing:
m_strategy = makeUnique<DefiniteSizeStrategy>(*this);
break;
}
m_contentSizedTracksIndex.shrink(0);
m_flexibleSizedTracksIndex.shrink(0);
m_autoSizedTracksForStretchIndex.shrink(0);
if (availableSpace) {
LayoutUnit guttersSize = m_renderGrid->guttersSize(m_grid, direction, 0, m_grid.numTracks(direction), this->availableSpace(direction));
setFreeSpace(direction, *availableSpace - guttersSize);
} else
setFreeSpace(direction, std::nullopt);
tracks(direction).resize(numTracks);
m_needsSetup = false;
m_hasPercentSizedRowsIndefiniteHeight = false;
m_hasFlexibleMaxTrackBreadth = false;
computeBaselineAlignmentContext();
}
void GridTrackSizingAlgorithm::computeBaselineAlignmentContext()
{
GridAxis axis = gridAxisForDirection(m_direction);
m_baselineAlignment.clear(axis);
m_baselineAlignment.setBlockFlow(m_renderGrid->style().writingMode());
BaselineItemsCache& baselineItemsCache = axis == GridColumnAxis ? m_columnBaselineItemsMap : m_rowBaselineItemsMap;
BaselineItemsCache tmpBaselineItemsCache = baselineItemsCache;
for (auto* child : tmpBaselineItemsCache.keys()) {
// FIXME (jfernandez): We may have to get rid of the baseline participation
// flag (hence just using a HashSet) depending on the CSS WG resolution on
// https://github.com/w3c/csswg-drafts/issues/3046
if (canParticipateInBaselineAlignment(*child, axis)) {
updateBaselineAlignmentContext(*child, axis);
baselineItemsCache.set(child, true);
} else
baselineItemsCache.set(child, false);
}
}
static void removeSubgridMarginBorderPaddingFromTracks(Vector<GridTrack>& tracks, LayoutUnit mbp, bool forwards)
{
int numTracks = tracks.size();
int i = forwards ? 0 : numTracks - 1;
while (mbp > 0 && (forwards ? i < numTracks : i >= 0)) {
LayoutUnit size = tracks[i].baseSize();
if (size > mbp) {
size -= mbp;
mbp = 0;
} else {
mbp -= size;
size = 0;
}
tracks[i].setBaseSize(size);
forwards ? i++ : i--;
}
}
bool GridTrackSizingAlgorithm::copyUsedTrackSizesForSubgrid()
{
ASSERT(is<RenderGrid>(m_renderGrid->parent()));
RenderGrid* outer = downcast<RenderGrid>(m_renderGrid->parent());
GridTrackSizingAlgorithm& parentAlgo = outer->m_trackSizingAlgorithm;
GridTrackSizingDirection direction = GridLayoutFunctions::flowAwareDirectionForParent(*m_renderGrid, *outer, m_direction);
Vector<GridTrack>& parentTracks = parentAlgo.tracks(direction);
if (!parentTracks.size())
return false;
GridSpan span = outer->gridSpanForChild(*m_renderGrid, direction);
Vector<GridTrack>& allTracks = tracks(m_direction);
int numTracks = allTracks.size();
for (int i = 0; i < numTracks; i++)
allTracks[i] = parentTracks[i + span.startLine()];
if (GridLayoutFunctions::isSubgridReversedDirection(*outer, direction, *m_renderGrid))
allTracks.reverse();
LayoutUnit startMBP = (m_direction == ForColumns) ? m_renderGrid->marginAndBorderAndPaddingStart() : m_renderGrid->marginAndBorderAndPaddingBefore();
removeSubgridMarginBorderPaddingFromTracks(allTracks, startMBP, true);
LayoutUnit endMBP = (m_direction == ForColumns) ? m_renderGrid->marginAndBorderAndPaddingEnd() : m_renderGrid->marginAndBorderAndPaddingAfter();
removeSubgridMarginBorderPaddingFromTracks(allTracks, endMBP, false);
LayoutUnit gapDifference = (m_renderGrid->gridGap(m_direction, availableSpace(m_direction)) - outer->gridGap(direction)) / 2;
for (int i = 0; i < numTracks; i++) {
LayoutUnit size = allTracks[i].baseSize();
if (i)
size -= gapDifference;
if (i != numTracks - 1)
size -= gapDifference;
allTracks[i].setBaseSize(std::max(size, 0_lu));
}
return true;
}
void GridTrackSizingAlgorithm::run()
{
ASSERT(wasSetup());
StateMachine stateMachine(*this);
if (m_renderGrid->isSubgrid(m_direction) && copyUsedTrackSizesForSubgrid())
return;
// Step 1.
const std::optional<LayoutUnit> initialFreeSpace = freeSpace(m_direction);
initializeTrackSizes();
// Step 2.
if (!m_contentSizedTracksIndex.isEmpty())
resolveIntrinsicTrackSizes();
// This is not exactly a step of the track sizing algorithm, but we use the track sizes computed
// up to this moment (before maximization) to calculate the grid container intrinsic sizes.
computeGridContainerIntrinsicSizes();
if (freeSpace(m_direction)) {
LayoutUnit updatedFreeSpace = freeSpace(m_direction).value() - m_minContentSize;
setFreeSpace(m_direction, updatedFreeSpace);
if (updatedFreeSpace <= 0)
return;
}
// Step 3.
m_strategy->maximizeTracks(tracks(m_direction), m_direction == ForColumns ? m_freeSpaceColumns : m_freeSpaceRows);
if (m_strategy->isComputingSizeContainment())
return;
// Step 4.
stretchFlexibleTracks(initialFreeSpace);
// Step 5.
stretchAutoTracks();
}
void GridTrackSizingAlgorithm::reset()
{
ASSERT(wasSetup());
m_sizingState = ColumnSizingFirstIteration;
m_columns.shrink(0);
m_rows.shrink(0);
m_contentSizedTracksIndex.shrink(0);
m_flexibleSizedTracksIndex.shrink(0);
m_autoSizedTracksForStretchIndex.shrink(0);
setAvailableSpace(ForRows, std::nullopt);
setAvailableSpace(ForColumns, std::nullopt);
m_hasPercentSizedRowsIndefiniteHeight = false;
m_hasFlexibleMaxTrackBreadth = false;
}
#if ASSERT_ENABLED
bool GridTrackSizingAlgorithm::tracksAreWiderThanMinTrackBreadth() const
{
// Subgrids inherit their sizing directly from the parent, so may be unrelated
// to their initial base size.
if (m_renderGrid->isSubgrid(m_direction))
return true;
const Vector<GridTrack>& allTracks = tracks(m_direction);
for (size_t i = 0; i < allTracks.size(); ++i) {
const auto& trackSize = allTracks[i].cachedTrackSize();
if (initialBaseSize(trackSize) > allTracks[i].baseSize())
return false;
}
return true;
}
#endif // ASSERT_ENABLED
GridTrackSizingAlgorithm::StateMachine::StateMachine(GridTrackSizingAlgorithm& algorithm)
: m_algorithm(algorithm)
{
ASSERT(m_algorithm.isValidTransition());
ASSERT(!m_algorithm.m_needsSetup);
}
GridTrackSizingAlgorithm::StateMachine::~StateMachine()
{
m_algorithm.advanceNextState();
m_algorithm.m_needsSetup = true;
}
} // namespace WebCore