Deleted: trunk/Source/WebCore/rendering/mathml/RenderMathMLScripts.cpp.orig (225069 => 225070)
--- trunk/Source/WebCore/rendering/mathml/RenderMathMLScripts.cpp.orig 2017-11-21 08:37:59 UTC (rev 225069)
+++ trunk/Source/WebCore/rendering/mathml/RenderMathMLScripts.cpp.orig 2017-11-21 09:19:17 UTC (rev 225070)
@@ -1,490 +0,0 @@
-/*
- * Copyright (C) 2010 Alex Milowski (a...@milowski.com). All rights reserved.
- * Copyright (C) 2013 The MathJax Consortium.
- * Copyright (C) 2016 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 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 "RenderMathMLScripts.h"
-
-#if ENABLE(MATHML)
-
-#include "MathMLElement.h"
-#include "MathMLScriptsElement.h"
-#include "RenderMathMLOperator.h"
-#include <wtf/IsoMallocInlines.h>
-
-namespace WebCore {
-
-WTF_MAKE_ISO_ALLOCATED_IMPL(RenderMathMLScripts);
-
-static bool isPrescriptDelimiter(const RenderObject& renderObject)
-{
- return renderObject.node() && renderObject.node()->hasTagName(MathMLNames::mprescriptsTag);
-}
-
-RenderMathMLScripts::RenderMathMLScripts(MathMLScriptsElement& element, RenderStyle&& style)
- : RenderMathMLBlock(element, WTFMove(style))
-{
- // Determine what kind of sub/sup _expression_ we have by element name
- if (element.hasTagName(MathMLNames::msubTag))
- m_scriptType = Sub;
- else if (element.hasTagName(MathMLNames::msupTag))
- m_scriptType = Super;
- else if (element.hasTagName(MathMLNames::msubsupTag))
- m_scriptType = SubSup;
- else if (element.hasTagName(MathMLNames::munderTag))
- m_scriptType = Under;
- else if (element.hasTagName(MathMLNames::moverTag))
- m_scriptType = Over;
- else if (element.hasTagName(MathMLNames::munderoverTag))
- m_scriptType = UnderOver;
- else {
- ASSERT(element.hasTagName(MathMLNames::mmultiscriptsTag));
- m_scriptType = Multiscripts;
- }
-}
-
-MathMLScriptsElement& RenderMathMLScripts::element() const
-{
- return static_cast<MathMLScriptsElement&>(nodeForNonAnonymous());
-}
-
-RenderMathMLOperator* RenderMathMLScripts::unembellishedOperator()
-{
- auto base = firstChildBox();
- if (!is<RenderMathMLBlock>(base))
- return nullptr;
- return downcast<RenderMathMLBlock>(base)->unembellishedOperator();
-}
-
-std::optional<RenderMathMLScripts::ReferenceChildren> RenderMathMLScripts::validateAndGetReferenceChildren()
-{
- // All scripted elements must have at least one child.
- // The first child is the base.
- auto base = firstChildBox();
- if (!base)
- return std::nullopt;
-
- ReferenceChildren reference;
- reference.base = base;
- reference.firstPostScript = nullptr;
- reference.firstPreScript = nullptr;
- reference.prescriptDelimiter = nullptr;
-
- switch (m_scriptType) {
- case Sub:
- case Super:
- case Under:
- case Over: {
- // These elements must have exactly two children.
- // The second child is a postscript and there are no prescripts.
- // <msub> base subscript </msub>
- // <msup> base superscript </msup>
- // <munder> base underscript </munder>
- // <mover> base overscript </mover>
- auto script = base->nextSiblingBox();
- if (!script || isPrescriptDelimiter(*script) || script->nextSiblingBox())
- return std::nullopt;
- reference.firstPostScript = script;
- return reference;
- }
- case SubSup:
- case UnderOver: {
- // These elements must have exactly three children.
- // The second and third children are postscripts and there are no prescripts.
- // <msubsup> base subscript superscript </msubsup>
- // <munderover> base subscript superscript </munderover>
- auto subScript = base->nextSiblingBox();
- if (!subScript || isPrescriptDelimiter(*subScript))
- return std::nullopt;
- auto superScript = subScript->nextSiblingBox();
- if (!superScript || isPrescriptDelimiter(*superScript) || superScript->nextSiblingBox())
- return std::nullopt;
- reference.firstPostScript = subScript;
- return reference;
- }
- case Multiscripts: {
- // This element accepts the following syntax:
- //
- // <mmultiscripts>
- // base
- // (subscript superscript)*
- // [ <mprescripts/> (presubscript presuperscript)* ]
- // </mmultiscripts>
- //
- // https://www.w3.org/TR/MathML3/chapter3.html#presm.mmultiscripts
- //
- // We set the first postscript, unless (subscript superscript)* is empty.
- if (base->nextSiblingBox() && !isPrescriptDelimiter(*base->nextSiblingBox()))
- reference.firstPostScript = base->nextSiblingBox();
-
- // We browse the children in order to
- // 1) Set the first prescript, unless (presubscript presuperscript)* is empty.
- // 2) Ensure the validity of the element i.e.
- // a) That the list of postscripts can be grouped into pairs of subscript/superscript.
- // b) That the list of prescripts can be grouped into pairs of subscript/superscript.
- // c) That there is at most one <mprescripts/>.
- bool numberOfScriptIsEven = true;
- for (auto script = base->nextSiblingBox(); script; script = script->nextSiblingBox()) {
- if (isPrescriptDelimiter(*script)) {
- // This is a <mprescripts/>. Let's check 2a) and 2c).
- if (!numberOfScriptIsEven || reference.firstPreScript)
- return std::nullopt;
- reference.firstPreScript = script->nextSiblingBox(); // We do 1).
- reference.prescriptDelimiter = script;
- continue;
- }
- numberOfScriptIsEven = !numberOfScriptIsEven;
- }
- return numberOfScriptIsEven ? std::optional<ReferenceChildren>(reference) : std::nullopt; // We verify 2b).
- }
- }
-
- ASSERT_NOT_REACHED();
- return std::nullopt;
-}
-
-LayoutUnit RenderMathMLScripts::spaceAfterScript()
-{
- const auto& primaryFont = style().fontCascade().primaryFont();
- if (auto* mathData = primaryFont.mathData())
- return mathData->getMathConstant(primaryFont, OpenTypeMathData::SpaceAfterScript);
- return style().fontCascade().size() / 5;
-}
-
-LayoutUnit RenderMathMLScripts::italicCorrection(const ReferenceChildren& reference)
-{
- if (is<RenderMathMLBlock>(*reference.base)) {
- if (auto* renderOperator = downcast<RenderMathMLBlock>(*reference.base).unembellishedOperator())
- return renderOperator->italicCorrection();
- }
- return 0;
-}
-
-void RenderMathMLScripts::computePreferredLogicalWidths()
-{
- ASSERT(preferredLogicalWidthsDirty());
-
- m_minPreferredLogicalWidth = 0;
- m_maxPreferredLogicalWidth = 0;
-
- auto possibleReference = validateAndGetReferenceChildren();
- if (!possibleReference) {
- setPreferredLogicalWidthsDirty(false);
- return;
- }
- auto& reference = possibleReference.value();
-
- LayoutUnit baseItalicCorrection = std::min(reference.base->maxPreferredLogicalWidth(), italicCorrection(reference));
- LayoutUnit space = spaceAfterScript();
-
- switch (m_scriptType) {
- case Sub:
- case Under:
- m_maxPreferredLogicalWidth += reference.base->maxPreferredLogicalWidth();
- m_maxPreferredLogicalWidth += std::max(LayoutUnit(0), reference.firstPostScript->maxPreferredLogicalWidth() - baseItalicCorrection + space);
- break;
- case Super:
- case Over:
- m_maxPreferredLogicalWidth += reference.base->maxPreferredLogicalWidth();
- m_maxPreferredLogicalWidth += std::max(LayoutUnit(0), reference.firstPostScript->maxPreferredLogicalWidth() + space);
- break;
- case SubSup:
- case UnderOver:
- case Multiscripts: {
- auto subScript = reference.firstPreScript;
- while (subScript) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subSupPairWidth = std::max(subScript->maxPreferredLogicalWidth(), supScript->maxPreferredLogicalWidth());
- m_maxPreferredLogicalWidth += subSupPairWidth + space;
- subScript = supScript->nextSiblingBox();
- }
- m_maxPreferredLogicalWidth += reference.base->maxPreferredLogicalWidth();
- subScript = reference.firstPostScript;
- while (subScript && subScript != reference.prescriptDelimiter) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subSupPairWidth = std::max(std::max(LayoutUnit(0), subScript->maxPreferredLogicalWidth() - baseItalicCorrection), supScript->maxPreferredLogicalWidth());
- m_maxPreferredLogicalWidth += subSupPairWidth + space;
- subScript = supScript->nextSiblingBox();
- }
- }
- }
-
- m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth;
-
- setPreferredLogicalWidthsDirty(false);
-}
-
-auto RenderMathMLScripts::verticalParameters() const -> VerticalParameters
-{
- VerticalParameters parameters;
- const auto& primaryFont = style().fontCascade().primaryFont();
- if (auto* mathData = primaryFont.mathData()) {
- parameters.subscriptShiftDown = mathData->getMathConstant(primaryFont, OpenTypeMathData::SubscriptShiftDown);
- parameters.superscriptShiftUp = mathData->getMathConstant(primaryFont, OpenTypeMathData::SuperscriptShiftUp);
- parameters.subscriptBaselineDropMin = mathData->getMathConstant(primaryFont, OpenTypeMathData::SubscriptBaselineDropMin);
- parameters.superScriptBaselineDropMax = mathData->getMathConstant(primaryFont, OpenTypeMathData::SuperscriptBaselineDropMax);
- parameters.subSuperscriptGapMin = mathData->getMathConstant(primaryFont, OpenTypeMathData::SubSuperscriptGapMin);
- parameters.superscriptBottomMin = mathData->getMathConstant(primaryFont, OpenTypeMathData::SuperscriptBottomMin);
- parameters.subscriptTopMax = mathData->getMathConstant(primaryFont, OpenTypeMathData::SubscriptTopMax);
- parameters.superscriptBottomMaxWithSubscript = mathData->getMathConstant(primaryFont, OpenTypeMathData::SuperscriptBottomMaxWithSubscript);
- } else {
- // Default heuristic values when you do not have a font.
- parameters.subscriptShiftDown = style().fontMetrics().xHeight() / 3;
- parameters.superscriptShiftUp = style().fontMetrics().xHeight();
- parameters.subscriptBaselineDropMin = style().fontMetrics().xHeight() / 2;
- parameters.superScriptBaselineDropMax = style().fontMetrics().xHeight() / 2;
- parameters.subSuperscriptGapMin = style().fontCascade().size() / 5;
- parameters.superscriptBottomMin = style().fontMetrics().xHeight() / 4;
- parameters.subscriptTopMax = 4 * style().fontMetrics().xHeight() / 5;
- parameters.superscriptBottomMaxWithSubscript = 4 * style().fontMetrics().xHeight() / 5;
- }
- return parameters;
-}
-
-RenderMathMLScripts::VerticalMetrics RenderMathMLScripts::verticalMetrics(const ReferenceChildren& reference)
-{
- VerticalParameters parameters = verticalParameters();
- VerticalMetrics metrics = { 0, 0, 0, 0 };
-
- LayoutUnit baseAscent = ascentForChild(*reference.base);
- LayoutUnit baseDescent = reference.base->logicalHeight() - baseAscent;
- if (m_scriptType == Sub || m_scriptType == SubSup || m_scriptType == Multiscripts || m_scriptType == Under || m_scriptType == UnderOver) {
- metrics.subShift = std::max(parameters.subscriptShiftDown, baseDescent + parameters.subscriptBaselineDropMin);
- if (!isRenderMathMLUnderOver()) {
- // It is not clear how to interpret the default shift and it is not available yet anyway.
- // Hence we just pass 0 as the default value used by toUserUnits.
- LayoutUnit specifiedMinSubShift = toUserUnits(element().subscriptShift(), style(), 0);
- metrics.subShift = std::max(metrics.subShift, specifiedMinSubShift);
- }
- }
- if (m_scriptType == Super || m_scriptType == SubSup || m_scriptType == Multiscripts || m_scriptType == Over || m_scriptType == UnderOver) {
- metrics.supShift = std::max(parameters.superscriptShiftUp, baseAscent - parameters.superScriptBaselineDropMax);
- if (!isRenderMathMLUnderOver()) {
- // It is not clear how to interpret the default shift and it is not available yet anyway.
- // Hence we just pass 0 as the default value used by toUserUnits.
- LayoutUnit specifiedMinSupShift = toUserUnits(element().superscriptShift(), style(), 0);
- metrics.supShift = std::max(metrics.supShift, specifiedMinSupShift);
- }
- }
-
- switch (m_scriptType) {
- case Sub:
- case Under: {
- LayoutUnit subAscent = ascentForChild(*reference.firstPostScript);
- LayoutUnit subDescent = reference.firstPostScript->logicalHeight() - subAscent;
- metrics.descent = subDescent;
- metrics.subShift = std::max(metrics.subShift, subAscent - parameters.subscriptTopMax);
- }
- break;
- case Super:
- case Over: {
- LayoutUnit supAscent = ascentForChild(*reference.firstPostScript);
- LayoutUnit supDescent = reference.firstPostScript->logicalHeight() - supAscent;
- metrics.ascent = supAscent;
- metrics.supShift = std::max(metrics.supShift, parameters.superscriptBottomMin + supDescent);
- }
- break;
- case SubSup:
- case UnderOver:
- case Multiscripts: {
- // FIXME: We should move the code updating VerticalMetrics for each sub/sup pair in a helper
- // function. That way, SubSup/UnderOver can just make one call and the loop for Multiscripts
- // can be rewritten in a more readable.
- auto subScript = reference.firstPostScript ? reference.firstPostScript : reference.firstPreScript;
- while (subScript) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subAscent = ascentForChild(*subScript);
- LayoutUnit subDescent = subScript->logicalHeight() - subAscent;
- LayoutUnit supAscent = ascentForChild(*supScript);
- LayoutUnit supDescent = supScript->logicalHeight() - supAscent;
- metrics.ascent = std::max(metrics.ascent, supAscent);
- metrics.descent = std::max(metrics.descent, subDescent);
- LayoutUnit subScriptShift = std::max(parameters.subscriptShiftDown, baseDescent + parameters.subscriptBaselineDropMin);
- subScriptShift = std::max(subScriptShift, subAscent - parameters.subscriptTopMax);
- LayoutUnit supScriptShift = std::max(parameters.superscriptShiftUp, baseAscent - parameters.superScriptBaselineDropMax);
- supScriptShift = std::max(supScriptShift, parameters.superscriptBottomMin + supDescent);
-
- LayoutUnit subSuperscriptGap = (subScriptShift - subAscent) + (supScriptShift - supDescent);
- if (subSuperscriptGap < parameters.subSuperscriptGapMin) {
- // First, we try and push the superscript up.
- LayoutUnit delta = parameters.superscriptBottomMaxWithSubscript - (supScriptShift - supDescent);
- if (delta > 0) {
- delta = std::min(delta, parameters.subSuperscriptGapMin - subSuperscriptGap);
- supScriptShift += delta;
- subSuperscriptGap += delta;
- }
- // If that is not enough, we push the subscript down.
- if (subSuperscriptGap < parameters.subSuperscriptGapMin)
- subScriptShift += parameters.subSuperscriptGapMin - subSuperscriptGap;
- }
-
- metrics.subShift = std::max(metrics.subShift, subScriptShift);
- metrics.supShift = std::max(metrics.supShift, supScriptShift);
-
- subScript = supScript->nextSiblingBox();
- if (subScript == reference.prescriptDelimiter)
- subScript = reference.firstPreScript;
- }
- }
- }
-
- return metrics;
-}
-
-void RenderMathMLScripts::layoutBlock(bool relayoutChildren, LayoutUnit)
-{
- ASSERT(needsLayout());
-
- if (!relayoutChildren && simplifiedLayout())
- return;
-
- auto possibleReference = validateAndGetReferenceChildren();
- if (!possibleReference) {
- layoutInvalidMarkup(relayoutChildren);
- return;
- }
- auto& reference = possibleReference.value();
-
- recomputeLogicalWidth();
- for (auto child = firstChildBox(); child; child = child->nextSiblingBox())
- child->layoutIfNeeded();
-
- LayoutUnit space = spaceAfterScript();
-
- // We determine the minimal shift/size of each script and take the maximum of the values.
- VerticalMetrics metrics = verticalMetrics(reference);
-
- LayoutUnit baseAscent = ascentForChild(*reference.base);
- LayoutUnit baseDescent = reference.base->logicalHeight() - baseAscent;
- LayoutUnit baseItalicCorrection = std::min(reference.base->logicalWidth(), italicCorrection(reference));
- LayoutUnit horizontalOffset = 0;
-
- LayoutUnit ascent = std::max(baseAscent, metrics.ascent + metrics.supShift);
- LayoutUnit descent = std::max(baseDescent, metrics.descent + metrics.subShift);
- setLogicalHeight(ascent + descent);
-
- switch (m_scriptType) {
- case Sub:
- case Under: {
- setLogicalWidth(reference.base->logicalWidth() + std::max(LayoutUnit(0), reference.firstPostScript->logicalWidth() - baseItalicCorrection + space));
- LayoutPoint baseLocation(mirrorIfNeeded(horizontalOffset, *reference.base), ascent - baseAscent);
- reference.base->setLocation(baseLocation);
- horizontalOffset += reference.base->logicalWidth();
- LayoutUnit scriptAscent = ascentForChild(*reference.firstPostScript);
- LayoutPoint scriptLocation(mirrorIfNeeded(horizontalOffset - baseItalicCorrection, *reference.firstPostScript), ascent + metrics.subShift - scriptAscent);
- reference.firstPostScript->setLocation(scriptLocation);
- }
- break;
- case Super:
- case Over: {
- setLogicalWidth(reference.base->logicalWidth() + std::max(LayoutUnit(0), reference.firstPostScript->logicalWidth() + space));
- LayoutPoint baseLocation(mirrorIfNeeded(horizontalOffset, *reference.base), ascent - baseAscent);
- reference.base->setLocation(baseLocation);
- horizontalOffset += reference.base->logicalWidth();
- LayoutUnit scriptAscent = ascentForChild(*reference.firstPostScript);
- LayoutPoint scriptLocation(mirrorIfNeeded(horizontalOffset, *reference.firstPostScript), ascent - metrics.supShift - scriptAscent);
- reference.firstPostScript->setLocation(scriptLocation);
- }
- break;
- case SubSup:
- case UnderOver:
- case Multiscripts: {
- // Calculate the logical width.
- LayoutUnit logicalWidth = 0;
- auto subScript = reference.firstPreScript;
- while (subScript) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subSupPairWidth = std::max(subScript->logicalWidth(), supScript->logicalWidth());
- logicalWidth += subSupPairWidth + space;
- subScript = supScript->nextSiblingBox();
- }
- logicalWidth += reference.base->logicalWidth();
- subScript = reference.firstPostScript;
- while (subScript && subScript != reference.prescriptDelimiter) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subSupPairWidth = std::max(std::max(LayoutUnit(0), subScript->logicalWidth() - baseItalicCorrection), supScript->logicalWidth());
- logicalWidth += subSupPairWidth + space;
- subScript = supScript->nextSiblingBox();
- }
- setLogicalWidth(logicalWidth);
-
- subScript = reference.firstPreScript;
- while (subScript) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subSupPairWidth = std::max(subScript->logicalWidth(), supScript->logicalWidth());
- horizontalOffset += space + subSupPairWidth;
- LayoutUnit subAscent = ascentForChild(*subScript);
- LayoutPoint subScriptLocation(mirrorIfNeeded(horizontalOffset - subScript->logicalWidth(), *subScript), ascent + metrics.subShift - subAscent);
- subScript->setLocation(subScriptLocation);
- LayoutUnit supAscent = ascentForChild(*supScript);
- LayoutPoint supScriptLocation(mirrorIfNeeded(horizontalOffset - supScript->logicalWidth(), *supScript), ascent - metrics.supShift - supAscent);
- supScript->setLocation(supScriptLocation);
- subScript = supScript->nextSiblingBox();
- }
- LayoutPoint baseLocation(mirrorIfNeeded(horizontalOffset, *reference.base), ascent - baseAscent);
- reference.base->setLocation(baseLocation);
- horizontalOffset += reference.base->logicalWidth();
- subScript = reference.firstPostScript;
- while (subScript && subScript != reference.prescriptDelimiter) {
- auto supScript = subScript->nextSiblingBox();
- ASSERT(supScript);
- LayoutUnit subAscent = ascentForChild(*subScript);
- LayoutPoint subScriptLocation(mirrorIfNeeded(horizontalOffset - baseItalicCorrection, *subScript), ascent + metrics.subShift - subAscent);
- subScript->setLocation(subScriptLocation);
- LayoutUnit supAscent = ascentForChild(*supScript);
- LayoutPoint supScriptLocation(mirrorIfNeeded(horizontalOffset, *supScript), ascent - metrics.supShift - supAscent);
- supScript->setLocation(supScriptLocation);
-
- LayoutUnit subSupPairWidth = std::max(subScript->logicalWidth(), supScript->logicalWidth());
- horizontalOffset += subSupPairWidth + space;
- subScript = supScript->nextSiblingBox();
- }
- }
- }
-
- layoutPositionedObjects(relayoutChildren);
-
- clearNeedsLayout();
-}
-
-std::optional<int> RenderMathMLScripts::firstLineBaseline() const
-{
- ASSERT(!needsLayout());
- auto* base = firstChildBox();
- if (!base)
- return std::optional<int>();
- return std::optional<int>(static_cast<int>(lroundf(ascentForChild(*base) + base->logicalTop())));
-}
-
-}
-
-#endif // ENABLE(MATHML)
