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diff --git a/Source/WebCore/rendering/mathml/RenderMathMLUnderOver.cpp b/Source/WebCore/rendering/mathml/RenderMathMLUnderOver.cpp
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+/*
+ * Copyright (C) 2009 Alex Milowski (alex@milowski.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"
+
+#if ENABLE(MATHML)
+
+#include "RenderMathMLUnderOver.h"
+
+#include "FontSelector.h"
+#include "MathMLNames.h"
+
+namespace WebCore {
+
+using namespace MathMLNames;
+
+static const double gOverSpacingAdjustment = 0.5;
+
+RenderMathMLUnderOver::RenderMathMLUnderOver(Node* expression)
+ : RenderMathMLBlock(expression)
+{
+ Element* element = static_cast<Element*>(expression);
+ // Determine what kind of under/over expression we have by element name
+
+ if (element->hasLocalName(MathMLNames::munderTag))
+ m_kind = Under;
+ else if (element->hasLocalName(MathMLNames::moverTag))
+ m_kind = Over;
+ else if (element->hasLocalName(MathMLNames::munderoverTag))
+ m_kind = UnderOver;
+ else
+ m_kind = Under;
+
+}
+
+void RenderMathMLUnderOver::addChild(RenderObject* child, RenderObject* beforeChild)
+{
+ RenderMathMLBlock* row = new (renderArena()) RenderMathMLBlock(node());
+ RefPtr<RenderStyle> rowStyle = makeBlockStyle();
+ row->setStyle(rowStyle.release());
+
+ // look through the children for rendered elements counting the blocks so we know what child
+ // we are adding
+ int blocks = 0;
+ RenderObject* current = this->firstChild();
+ while (current) {
+ blocks++;
+ current = current->nextSibling();
+ }
+
+ switch (blocks) {
+ case 0:
+ // this is the base so just append it
+ RenderBlock::addChild(row, beforeChild);
+ break;
+ case 1:
+ // the under or over
+ // FIXME: text-align: center does not work
+ row->style()->setTextAlign(CENTER);
+ if (m_kind == Over) {
+ // add the over as first
+ RenderBlock::addChild(row, firstChild());
+ } else {
+ // add the under as last
+ RenderBlock::addChild(row, beforeChild);
+ }
+ break;
+ case 2:
+ // the under or over
+ // FIXME: text-align: center does not work
+ row->style()->setTextAlign(CENTER);
+ if (m_kind == UnderOver) {
+ // add the over as first
+ RenderBlock::addChild(row, firstChild());
+ } else {
+ // we really shouldn't get here as only munderover should have three children
+ RenderBlock::addChild(row, beforeChild);
+ }
+ break;
+ default:
+ // munderover shouldn't have more than three children. In theory we shouldn't
+ // get here if the MathML is correctly formed, but that isn't a guarantee.
+ // We will treat this as another under element and they'll get something funky.
+ RenderBlock::addChild(row, beforeChild);
+ }
+ row->addChild(child);
+}
+
+inline int getOffsetHeight(RenderObject* obj)
+{
+ if (obj->isBoxModelObject()) {
+ RenderBoxModelObject* box = toRenderBoxModelObject(obj);
+ return box->offsetHeight();
+ }
+
+ return 0;
+}
+
+void RenderMathMLUnderOver::stretchToHeight(int height)
+{
+
+ RenderObject* base = firstChild();
+ if (!base)
+ return;
+
+ // For over or underover, the base is the sibling of the first child
+ if (m_kind != Under)
+ base = base->nextSibling();
+
+ if (!base)
+ return;
+
+ // use the child of the row which is the actual base
+ base = base->firstChild();
+
+ if (base && base->isRenderMathMLBlock()) {
+ RenderMathMLBlock* block = toRenderMathMLBlock(base);
+ block->stretchToHeight(height);
+ setNeedsLayout(true);
+ }
+}
+
+void RenderMathMLUnderOver::layout()
+{
+ RenderBlock::layout();
+ RenderObject* over = 0;
+ RenderObject* base = 0;
+ switch (m_kind) {
+ case Over:
+ // We need to calculate the baseline over the over versus the start of the base and
+ // adjust the placement of the base.
+ over = firstChild();
+ if (over) {
+ // FIXME: descending glyphs intrude into base (e.g. lowercase y over base)
+ // FIXME: bases that ascend higher than the line box intrude into the over
+ if (!over->firstChild()->isBoxModelObject())
+ break;
+
+ int overSpacing = static_cast<int>(gOverSpacingAdjustment * (getOffsetHeight(over) - toRenderBoxModelObject(over->firstChild())->baselinePosition(AlphabeticBaseline, true, HorizontalLine)));
+
+ // base row wrapper
+ base = over->nextSibling();
+ if (base) {
+ if (overSpacing > 0)
+ base->style()->setMarginTop(Length(-overSpacing, Fixed));
+ else
+ base->style()->setMarginTop(Length(0, Fixed));
+ }
+
+ }
+ break;
+ case Under:
+ // FIXME: Non-ascending glyphs in the under should be moved closer to the base
+
+ // We need to calculate the baseline of the base versus the start of the under block and
+ // adjust the placement of the under block.
+
+ // base row wrapper
+ base = firstChild();
+ if (base) {
+ int baseHeight = getOffsetHeight(base);
+ // actual base
+ base = base->firstChild();
+ if (!base->isBoxModelObject())
+ break;
+
+ // FIXME: We need to look at the space between a single maximum height of
+ // the line boxes and the baseline and squeeze them together
+ int underSpacing = baseHeight - toRenderBoxModelObject(base)->baselinePosition(AlphabeticBaseline, true, HorizontalLine);
+
+ // adjust the base's intrusion into the under
+ RenderObject* under = lastChild();
+ if (under && underSpacing > 0)
+ under->style()->setMarginTop(Length(-underSpacing, Fixed));
+ }
+ break;
+ case UnderOver:
+ // FIXME: Non-descending glyphs in the over should be moved closer to the base
+ // FIXME: Non-ascending glyphs in the under should be moved closer to the base
+
+ // We need to calculate the baseline of the over versus the start of the base and
+ // adjust the placement of the base.
+
+ over = firstChild();
+ if (over) {
+ // FIXME: descending glyphs intrude into base (e.g. lowercase y over base)
+ // FIXME: bases that ascend higher than the line box intrude into the over
+ if (!over->firstChild()->isBoxModelObject())
+ break;
+ int overSpacing = static_cast<int>(gOverSpacingAdjustment * (getOffsetHeight(over) - toRenderBoxModelObject(over->firstChild())->baselinePosition(AlphabeticBaseline, true, HorizontalLine)));
+
+ // base row wrapper
+ base = over->nextSibling();
+
+ if (base) {
+ if (overSpacing > 0)
+ base->style()->setMarginTop(Length(-overSpacing, Fixed));
+
+ // We need to calculate the baseline of the base versus the start of the under block and
+ // adjust the placement of the under block.
+
+ int baseHeight = getOffsetHeight(base);
+ // actual base
+ base = base->firstChild();
+ if (!base->isBoxModelObject())
+ break;
+
+ // FIXME: We need to look at the space between a single maximum height of
+ // the line boxes and the baseline and squeeze them together
+ int underSpacing = baseHeight - toRenderBoxModelObject(base)->baselinePosition(AlphabeticBaseline, true, HorizontalLine);
+
+ RenderObject* under = lastChild();
+ if (under && under->firstChild()->isRenderInline() && underSpacing > 0)
+ under->style()->setMarginTop(Length(-underSpacing, Fixed));
+
+ }
+ }
+ break;
+ }
+ setNeedsLayout(true);
+ RenderBlock::layout();
+}
+
+int RenderMathMLUnderOver::baselinePosition(FontBaseline, bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const
+{
+ RenderObject* current = firstChild();
+ if (!current)
+ return RenderBlock::baselinePosition(AlphabeticBaseline, firstLine, direction, linePositionMode);
+
+ int baseline = 0;
+ switch (m_kind) {
+ case UnderOver:
+ case Over:
+ baseline += getOffsetHeight(current);
+ current = current->nextSibling();
+ if (current) {
+ // actual base
+ RenderObject* base = current->firstChild();
+ if (!base || !base->isBoxModelObject())
+ break;
+ baseline += toRenderBoxModelObject(base)->baselinePosition(AlphabeticBaseline, firstLine, HorizontalLine, linePositionMode);
+ // added the negative top margin
+ baseline += current->style()->marginTop().value();
+ }
+ break;
+ case Under:
+ RenderObject* base = current->firstChild();
+ if (base && base->isBoxModelObject())
+ baseline += toRenderBoxModelObject(base)->baselinePosition(AlphabeticBaseline, true, HorizontalLine);
+ }
+
+ // FIXME: Where is the extra 2-3px adjusted for zoom coming from?
+ float zoomFactor = style()->effectiveZoom();
+ baseline += static_cast<int>((zoomFactor > 1.25 ? 2 : 3) * zoomFactor);
+ return baseline;
+}
+
+
+int RenderMathMLUnderOver::nonOperatorHeight() const
+{
+ int nonOperators = 0;
+ for (RenderObject* current = firstChild(); current; current = current->nextSibling()) {
+ if (current->firstChild()->isRenderMathMLBlock()) {
+ RenderMathMLBlock* block = toRenderMathMLBlock(current->firstChild());
+ if (!block->isRenderMathMLOperator())
+ nonOperators += getOffsetHeight(current);
+ } else {
+ nonOperators += getOffsetHeight(current);
+ }
+ }
+ return nonOperators;
+}
+
+}
+
+
+#endif // ENABLE(MATHML)
generated by cgit v1.1 at 2025-05-14 05:33:24 +0000