1 files changed, 188 insertions, 0 deletions
diff --git a/Source/WebCore/rendering/mathml/RenderMathMLFraction.cpp b/Source/WebCore/rendering/mathml/RenderMathMLFraction.cpp
new file mode 100644
index 0000000..7117618
--- /dev/null
+++ b/Source/WebCore/rendering/mathml/RenderMathMLFraction.cpp
@@ -0,0 +1,188 @@
+/*
+ * Copyright (C) 2009 Alex Milowski (alex@milowski.com). All rights reserved.
+ * Copyright (C) 2010 François Sausset (sausset@gmail.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 "RenderMathMLFraction.h"
+
+#include "GraphicsContext.h"
+#include "MathMLNames.h"
+#include "PaintInfo.h"
+#include "RenderText.h"
+
+namespace WebCore {
+    
+using namespace MathMLNames;
+
+static const double gHorizontalPad = 0.2;
+static const double gLineThin = 0.33;
+static const double gLineMedium = 1.;
+static const double gLineThick = 3.;
+static const double gFractionBarWidth = 0.05;
+static const double gDenominatorPad = 0.1;
+
+RenderMathMLFraction::RenderMathMLFraction(Element* fraction) 
+    : RenderMathMLBlock(fraction)
+    , m_lineThickness(gLineMedium)
+{
+    setChildrenInline(false);
+}
+
+void RenderMathMLFraction::updateFromElement()
+{
+    // FIXME: mfrac where bevelled=true will need to reorganize the descendants
+    if (isEmpty()) 
+        return;
+    
+    Element* fraction = static_cast<Element*>(node());
+    
+    RenderObject* numerator = firstChild();
+    String nalign = fraction->getAttribute(MathMLNames::numalignAttr);
+    if (equalIgnoringCase(nalign, "left"))
+        numerator->style()->setTextAlign(LEFT);
+    else if (equalIgnoringCase(nalign, "right"))
+        numerator->style()->setTextAlign(RIGHT);
+    else
+        numerator->style()->setTextAlign(CENTER);
+    
+    RenderObject* denominator = numerator->nextSibling();
+    if (!denominator)
+        return;
+    
+    String dalign = fraction->getAttribute(MathMLNames::denomalignAttr);
+    if (equalIgnoringCase(dalign, "left"))
+        denominator->style()->setTextAlign(LEFT);
+    else if (equalIgnoringCase(dalign, "right"))
+        denominator->style()->setTextAlign(RIGHT);
+    else
+        denominator->style()->setTextAlign(CENTER);
+    
+    // FIXME: parse units
+    String thickness = fraction->getAttribute(MathMLNames::linethicknessAttr);
+    m_lineThickness = gLineMedium;
+    if (equalIgnoringCase(thickness, "thin"))
+        m_lineThickness = gLineThin;
+    else if (equalIgnoringCase(thickness, "medium"))
+        m_lineThickness = gLineMedium;
+    else if (equalIgnoringCase(thickness, "thick"))
+        m_lineThickness = gLineThick;
+    else if (equalIgnoringCase(thickness, "0"))
+        m_lineThickness = 0;
+
+    // Update the style for the padding of the denominator for the line thickness
+    lastChild()->style()->setPaddingTop(Length(static_cast<int>(m_lineThickness + style()->fontSize() * gDenominatorPad), Fixed));
+}
+
+void RenderMathMLFraction::addChild(RenderObject* child, RenderObject* beforeChild)
+{
+    RenderBlock* row = new (renderArena()) RenderMathMLBlock(node());
+    RefPtr<RenderStyle> rowStyle = makeBlockStyle();
+    
+    rowStyle->setTextAlign(CENTER);
+    Length pad(static_cast<int>(rowStyle->fontSize() * gHorizontalPad), Fixed);
+    rowStyle->setPaddingLeft(pad);
+    rowStyle->setPaddingRight(pad);
+    
+    // Only add padding for rows as denominators
+    bool isNumerator = isEmpty();
+    if (!isNumerator) 
+        rowStyle->setPaddingTop(Length(2, Fixed));
+    
+    row->setStyle(rowStyle.release());
+    RenderBlock::addChild(row, beforeChild);
+    row->addChild(child);
+    updateFromElement();
+}
+
+void RenderMathMLFraction::layout()
+{
+    updateFromElement();
+
+    // Adjust the fraction line thickness for the zoom
+    if (lastChild() && lastChild()->isRenderBlock())
+        m_lineThickness *= ceil(gFractionBarWidth * style()->fontSize());
+
+    RenderBlock::layout();
+
+}
+
+void RenderMathMLFraction::paint(PaintInfo& info, int tx, int ty)
+{
+    RenderMathMLBlock::paint(info, tx, ty);
+    if (info.context->paintingDisabled() || info.phase != PaintPhaseForeground)
+        return;
+    
+    if (!firstChild() ||!m_lineThickness)
+        return;
+
+    int verticalOffset = 0;
+    // The children are always RenderMathMLBlock instances
+    if (firstChild()->isRenderMathMLBlock()) {
+        int adjustForThickness = m_lineThickness > 1 ? int(m_lineThickness / 2) : 1;
+        if (int(m_lineThickness) % 2 == 1)
+            adjustForThickness++;
+        RenderMathMLBlock* numerator = toRenderMathMLBlock(firstChild());
+        if (numerator->isRenderMathMLRow())
+            verticalOffset = numerator->offsetHeight() + adjustForThickness;
+        else 
+            verticalOffset = numerator->offsetHeight();        
+    }
+    
+    tx += x();
+    ty += y() + verticalOffset;
+    
+    info.context->save();
+    
+    info.context->setStrokeThickness(static_cast<float>(m_lineThickness));
+    info.context->setStrokeStyle(SolidStroke);
+    info.context->setStrokeColor(style()->visitedDependentColor(CSSPropertyColor), ColorSpaceSRGB);
+    
+    info.context->drawLine(IntPoint(tx, ty), IntPoint(tx + offsetWidth(), ty));
+    
+    info.context->restore();
+}
+
+int RenderMathMLFraction::baselinePosition(FontBaseline, bool firstLine, LineDirectionMode lineDirection, LinePositionMode linePositionMode) const
+{
+    if (firstChild() && firstChild()->isRenderMathMLBlock()) {
+        RenderMathMLBlock* numerator = toRenderMathMLBlock(firstChild());
+        RenderStyle* refStyle = style();
+        if (previousSibling())
+            refStyle = previousSibling()->style();
+        else if (nextSibling())
+            refStyle = nextSibling()->style();
+        int shift = int(ceil((refStyle->font().xHeight() + 1) / 2));
+        return numerator->offsetHeight() + shift;
+    }
+    return RenderBlock::baselinePosition(AlphabeticBaseline, firstLine, lineDirection, linePositionMode);
+}
+
+}
+
+
+#endif // ENABLE(MATHML)