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/*
* Copyright (C) 2009 Alex Milowski (alex@milowski.com). All rights reserved.
* Copyright (C) 2012 David Barton (dbarton@mathscribe.com). 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
* OWNER 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 "RenderMathMLBlock.h"
#if ENABLE(MATHML)
#include "CSSHelper.h"
#include "GraphicsContext.h"
#include "LayoutRepainter.h"
#include "MathMLElement.h"
#include "MathMLNames.h"
#include "MathMLPresentationElement.h"
#include "RenderView.h"
#include <wtf/IsoMallocInlines.h>
#if ENABLE(DEBUG_MATH_LAYOUT)
#include "PaintInfo.h"
#endif
namespace WebCore {
using namespace MathMLNames;
WTF_MAKE_ISO_ALLOCATED_IMPL(RenderMathMLBlock);
WTF_MAKE_ISO_ALLOCATED_IMPL(RenderMathMLTable);
RenderMathMLBlock::RenderMathMLBlock(MathMLPresentationElement& container, RenderStyle&& style)
: RenderBlock(container, WTFMove(style), 0)
, m_mathMLStyle(MathMLStyle::create())
{
setChildrenInline(false); // All of our children must be block-level.
}
RenderMathMLBlock::RenderMathMLBlock(Document& document, RenderStyle&& style)
: RenderBlock(document, WTFMove(style), 0)
, m_mathMLStyle(MathMLStyle::create())
{
setChildrenInline(false); // All of our children must be block-level.
}
RenderMathMLBlock::~RenderMathMLBlock() = default;
bool RenderMathMLBlock::isChildAllowed(const RenderObject& child, const RenderStyle&) const
{
return is<Element>(child.node());
}
static LayoutUnit axisHeight(const RenderStyle& style)
{
// If we have a MATH table we just return the AxisHeight constant.
const auto& primaryFont = style.fontCascade().primaryFont();
if (auto* mathData = primaryFont.mathData())
return mathData->getMathConstant(primaryFont, OpenTypeMathData::AxisHeight);
// Otherwise, the idea is to try and use the middle of operators as the math axis which we thus approximate by "half of the x-height".
// Note that Gecko has a slower but more accurate version that measures half of the height of U+2212 MINUS SIGN.
return style.fontMetrics().xHeight() / 2;
}
LayoutUnit RenderMathMLBlock::mathAxisHeight() const
{
return axisHeight(style());
}
LayoutUnit RenderMathMLBlock::mirrorIfNeeded(LayoutUnit horizontalOffset, LayoutUnit boxWidth) const
{
if (style().direction() == TextDirection::RTL)
return logicalWidth() - boxWidth - horizontalOffset;
return horizontalOffset;
}
int RenderMathMLBlock::baselinePosition(FontBaseline baselineType, bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const
{
// mathml.css sets math { -webkit-line-box-contain: glyphs replaced; line-height: 0; }, so when linePositionMode == PositionOfInteriorLineBoxes we want to
// return 0 here to match our line-height. This matters when RootInlineBox::ascentAndDescentForBox is called on a RootInlineBox for an inline-block.
if (linePositionMode == PositionOfInteriorLineBoxes)
return 0;
return firstLineBaseline().valueOr(RenderBlock::baselinePosition(baselineType, firstLine, direction, linePositionMode));
}
#if ENABLE(DEBUG_MATH_LAYOUT)
void RenderMathMLBlock::paint(PaintInfo& info, const LayoutPoint& paintOffset)
{
RenderBlock::paint(info, paintOffset);
if (info.context().paintingDisabled() || info.phase != PaintPhase::Foreground)
return;
IntPoint adjustedPaintOffset = roundedIntPoint(paintOffset + location());
GraphicsContextStateSaver stateSaver(info.context());
info.context().setStrokeThickness(1.0f);
info.context().setStrokeStyle(SolidStroke);
info.context().setStrokeColor(Color(0, 0, 255));
info.context().drawLine(adjustedPaintOffset, IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y()));
info.context().drawLine(IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y()), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight()));
info.context().drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight()), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight()));
info.context().drawLine(adjustedPaintOffset, IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight()));
int topStart = paddingTop();
info.context().setStrokeColor(Color(0, 255, 0));
info.context().drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + topStart), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + topStart));
int baseline = roundToInt(baselinePosition(AlphabeticBaseline, true, HorizontalLine));
info.context().setStrokeColor(Color(255, 0, 0));
info.context().drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + baseline), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + baseline));
}
#endif // ENABLE(DEBUG_MATH_LAYOUT)
LayoutUnit toUserUnits(const MathMLElement::Length& length, const RenderStyle& style, const LayoutUnit& referenceValue)
{
switch (length.type) {
// Zoom for physical units needs to be accounted for.
case MathMLElement::LengthType::Cm:
return style.effectiveZoom() * length.value * cssPixelsPerInch / 2.54f;
case MathMLElement::LengthType::In:
return style.effectiveZoom() * length.value * cssPixelsPerInch;
case MathMLElement::LengthType::Mm:
return style.effectiveZoom() * length.value * cssPixelsPerInch / 25.4f;
case MathMLElement::LengthType::Pc:
return style.effectiveZoom() * length.value * cssPixelsPerInch / 6;
case MathMLElement::LengthType::Pt:
return style.effectiveZoom() * length.value * cssPixelsPerInch / 72;
case MathMLElement::LengthType::Px:
return style.effectiveZoom() * length.value;
// Zoom for logical units is accounted for either in the font info or referenceValue.
case MathMLElement::LengthType::Em:
return length.value * style.fontCascade().size();
case MathMLElement::LengthType::Ex:
return length.value * style.fontMetrics().xHeight();
case MathMLElement::LengthType::MathUnit:
return length.value * style.fontCascade().size() / 18;
case MathMLElement::LengthType::Percentage:
return referenceValue * length.value / 100;
case MathMLElement::LengthType::UnitLess:
return referenceValue * length.value;
case MathMLElement::LengthType::ParsingFailed:
return referenceValue;
case MathMLElement::LengthType::Infinity:
return intMaxForLayoutUnit;
default:
ASSERT_NOT_REACHED();
return referenceValue;
}
}
Optional<int> RenderMathMLTable::firstLineBaseline() const
{
// By default the vertical center of <mtable> is aligned on the math axis.
// This is different than RenderTable::firstLineBoxBaseline, which returns the baseline of the first row of a <table>.
return Optional<int>(logicalHeight() / 2 + axisHeight(style()));
}
void RenderMathMLBlock::layoutItems(bool relayoutChildren)
{
LayoutUnit verticalOffset = borderBefore() + paddingBefore();
LayoutUnit horizontalOffset = borderStart() + paddingStart();
LayoutUnit preferredHorizontalExtent;
for (auto* child = firstChildBox(); child; child = child->nextSiblingBox()) {
LayoutUnit childHorizontalExtent = child->maxPreferredLogicalWidth() - child->horizontalBorderAndPaddingExtent();
LayoutUnit childHorizontalMarginBoxExtent = child->horizontalBorderAndPaddingExtent() + childHorizontalExtent;
childHorizontalMarginBoxExtent += child->horizontalMarginExtent();
preferredHorizontalExtent += childHorizontalMarginBoxExtent;
}
LayoutUnit currentHorizontalExtent = contentLogicalWidth();
for (auto* child = firstChildBox(); child; child = child->nextSiblingBox()) {
LayoutUnit childSize = child->maxPreferredLogicalWidth() - child->horizontalBorderAndPaddingExtent();
if (preferredHorizontalExtent > currentHorizontalExtent)
childSize = currentHorizontalExtent;
LayoutUnit childPreferredSize = childSize + child->horizontalBorderAndPaddingExtent();
if (childPreferredSize != child->width())
child->setChildNeedsLayout(MarkOnlyThis);
updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, *child);
child->layoutIfNeeded();
LayoutUnit childVerticalMarginBoxExtent;
childVerticalMarginBoxExtent = child->height() + child->verticalMarginExtent();
setLogicalHeight(std::max(logicalHeight(), verticalOffset + borderAfter() + paddingAfter() + childVerticalMarginBoxExtent + horizontalScrollbarHeight()));
horizontalOffset += child->marginStart();
LayoutUnit childHorizontalExtent = child->width();
LayoutPoint childLocation(style().isLeftToRightDirection() ? horizontalOffset : width() - horizontalOffset - childHorizontalExtent,
verticalOffset + child->marginBefore());
child->setLocation(childLocation);
horizontalOffset += childHorizontalExtent + child->marginEnd();
}
}
void RenderMathMLBlock::layoutBlock(bool relayoutChildren, LayoutUnit)
{
ASSERT(needsLayout());
if (!relayoutChildren && simplifiedLayout())
return;
LayoutRepainter repainter(*this, checkForRepaintDuringLayout());
if (recomputeLogicalWidth())
relayoutChildren = true;
setLogicalHeight(borderAndPaddingLogicalHeight() + scrollbarLogicalHeight());
layoutItems(relayoutChildren);
updateLogicalHeight();
layoutPositionedObjects(relayoutChildren);
repainter.repaintAfterLayout();
updateScrollInfoAfterLayout();
clearNeedsLayout();
}
void RenderMathMLBlock::layoutInvalidMarkup(bool relayoutChildren)
{
// Invalid MathML subtrees are just renderered as empty boxes.
// FIXME: https://webkit.org/b/135460 - Should we display some "invalid" markup message instead?
ASSERT(needsLayout());
for (auto child = firstChildBox(); child; child = child->nextSiblingBox())
child->layoutIfNeeded();
setLogicalWidth(0);
setLogicalHeight(0);
layoutPositionedObjects(relayoutChildren);
updateScrollInfoAfterLayout();
clearNeedsLayout();
}
}
#endif