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/*
* Copyright (C) 2018 Igalia S.L. 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. AND ITS CONTRIBUTORS ``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 ITS 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.
*/
#pragma once
#include "BaselineAlignment.h"
#include "GridLayoutFunctions.h"
#include "RenderStyleConstants.h"
#include "WritingMode.h"
#include <wtf/HashMap.h>
#include <wtf/HashSet.h>
namespace WebCore {
// This is the class that implements the Baseline Alignment logic, using internally the BaselineAlignmentState and
// BaselineGroup classes.
//
// The first phase is to collect the items that will participate in baseline alignment together. During this
// phase the required baseline-sharing groups will be created for each Baseline alignment-context shared by
// the items participating in the baseline alignment.
//
// Additionally, the baseline-sharing groups' offsets, max-ascend and max-descent will be computed and stored.
// This class also computes the baseline offset for a particular item, based on the max-ascent for its associated
// baseline-sharing group.
class GridBaselineAlignment {
public:
// Collects the items participating in baseline alignment and updates the corresponding baseline-sharing
// group of the Baseline Context the items belongs to.
// All the baseline offsets are updated accordingly based on the added item.
void updateBaselineAlignmentContext(ItemPosition, unsigned sharedContext, const RenderBox&, GridAxis);
// Returns the baseline offset of a particular item, based on the max-ascent for its associated
// baseline-sharing group
LayoutUnit baselineOffsetForGridItem(ItemPosition, unsigned sharedContext, const RenderBox&, GridAxis) const;
// Sets the Grid Container's writing mode so that we can avoid the dependecy of the LayoutGrid class for
// determining whether a grid item is orthogonal or not.
void setWritingMode(WritingMode writingMode) { m_writingMode = writingMode; };
// Clearing the Baseline Alignment context and their internal classes and data structures.
void clear(GridAxis);
private:
const BaselineGroup& baselineGroupForGridItem(ItemPosition, unsigned sharedContext, const RenderBox&, GridAxis) const;
LayoutUnit marginOverForGridItem(const RenderBox&, GridAxis) const;
LayoutUnit marginUnderForGridItem(const RenderBox&, GridAxis) const;
LayoutUnit logicalAscentForGridItem(const RenderBox&, GridAxis, ItemPosition) const;
LayoutUnit ascentForGridItem(const RenderBox&, GridAxis, ItemPosition) const;
LayoutUnit descentForGridItem(const RenderBox&, LayoutUnit, GridAxis, ExtraMarginsFromSubgrids) const;
bool isDescentBaselineForGridItem(const RenderBox&, GridAxis) const;
bool isVerticalAlignmentContext(GridAxis) const;
bool isOrthogonalGridItemForBaseline(const RenderBox&) const;
bool isParallelToAlignmentAxisForGridItem(const RenderBox&, GridAxis) const;
typedef UncheckedKeyHashMap<unsigned, std::unique_ptr<BaselineAlignmentState>, DefaultHash<unsigned>, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> BaselineAlignmentStateMap;
// Grid Container's writing mode, used to determine grid item's orthogonality.
WritingMode m_writingMode;
BaselineAlignmentStateMap m_rowAxisBaselineAlignmentStates;
BaselineAlignmentStateMap m_colAxisBaselineAlignmentStates;
};
} // namespace WebCore
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