1 /*
2 * Copyright (C) 2009 Alex Milowski (alex@milowski.com). All rights reserved.
3 * Copyright (C) 2010 François Sausset (sausset@gmail.com). All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
18 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
20 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include "config.h"
28
29 #if ENABLE(MATHML)
30
31 #include "RenderMathMLFraction.h"
32
33 #include "GraphicsContext.h"
34 #include "MathMLNames.h"
35 #include "PaintInfo.h"
36 #include "RenderText.h"
37
38 namespace WebCore {
39
40 using namespace MathMLNames;
41
42 static const float gHorizontalPad = 0.2f;
43 static const float gLineThin = 0.33f;
44 static const float gLineMedium = 1.f;
45 static const float gLineThick = 3.f;
46 static const float gFractionBarWidth = 0.05f;
47 static const float gDenominatorPad = 0.1f;
48
RenderMathMLFraction(Element * fraction)49 RenderMathMLFraction::RenderMathMLFraction(Element* fraction)
50 : RenderMathMLBlock(fraction)
51 , m_lineThickness(gLineMedium)
52 {
53 setChildrenInline(false);
54 }
55
updateFromElement()56 void RenderMathMLFraction::updateFromElement()
57 {
58 // FIXME: mfrac where bevelled=true will need to reorganize the descendants
59 if (isEmpty())
60 return;
61
62 Element* fraction = static_cast<Element*>(node());
63
64 RenderObject* numerator = firstChild();
65 String nalign = fraction->getAttribute(MathMLNames::numalignAttr);
66 if (equalIgnoringCase(nalign, "left"))
67 numerator->style()->setTextAlign(LEFT);
68 else if (equalIgnoringCase(nalign, "right"))
69 numerator->style()->setTextAlign(RIGHT);
70 else
71 numerator->style()->setTextAlign(CENTER);
72
73 RenderObject* denominator = numerator->nextSibling();
74 if (!denominator)
75 return;
76
77 String dalign = fraction->getAttribute(MathMLNames::denomalignAttr);
78 if (equalIgnoringCase(dalign, "left"))
79 denominator->style()->setTextAlign(LEFT);
80 else if (equalIgnoringCase(dalign, "right"))
81 denominator->style()->setTextAlign(RIGHT);
82 else
83 denominator->style()->setTextAlign(CENTER);
84
85 // FIXME: parse units
86 String thickness = fraction->getAttribute(MathMLNames::linethicknessAttr);
87 m_lineThickness = gLineMedium;
88 if (equalIgnoringCase(thickness, "thin"))
89 m_lineThickness = gLineThin;
90 else if (equalIgnoringCase(thickness, "medium"))
91 m_lineThickness = gLineMedium;
92 else if (equalIgnoringCase(thickness, "thick"))
93 m_lineThickness = gLineThick;
94 else if (equalIgnoringCase(thickness, "0"))
95 m_lineThickness = 0;
96
97 // Update the style for the padding of the denominator for the line thickness
98 lastChild()->style()->setPaddingTop(Length(static_cast<int>(m_lineThickness + style()->fontSize() * gDenominatorPad), Fixed));
99 }
100
addChild(RenderObject * child,RenderObject * beforeChild)101 void RenderMathMLFraction::addChild(RenderObject* child, RenderObject* beforeChild)
102 {
103 RenderBlock* row = new (renderArena()) RenderMathMLBlock(node());
104 RefPtr<RenderStyle> rowStyle = makeBlockStyle();
105
106 rowStyle->setTextAlign(CENTER);
107 Length pad(static_cast<int>(rowStyle->fontSize() * gHorizontalPad), Fixed);
108 rowStyle->setPaddingLeft(pad);
109 rowStyle->setPaddingRight(pad);
110
111 // Only add padding for rows as denominators
112 bool isNumerator = isEmpty();
113 if (!isNumerator)
114 rowStyle->setPaddingTop(Length(2, Fixed));
115
116 row->setStyle(rowStyle.release());
117 RenderBlock::addChild(row, beforeChild);
118 row->addChild(child);
119 updateFromElement();
120 }
121
layout()122 void RenderMathMLFraction::layout()
123 {
124 updateFromElement();
125
126 // Adjust the fraction line thickness for the zoom
127 if (lastChild() && lastChild()->isRenderBlock())
128 m_lineThickness *= ceilf(gFractionBarWidth * style()->fontSize());
129
130 RenderBlock::layout();
131
132 }
133
paint(PaintInfo & info,int tx,int ty)134 void RenderMathMLFraction::paint(PaintInfo& info, int tx, int ty)
135 {
136 RenderMathMLBlock::paint(info, tx, ty);
137 if (info.context->paintingDisabled() || info.phase != PaintPhaseForeground)
138 return;
139
140 if (!firstChild() ||!m_lineThickness)
141 return;
142
143 int verticalOffset = 0;
144 // The children are always RenderMathMLBlock instances
145 if (firstChild()->isRenderMathMLBlock()) {
146 int adjustForThickness = m_lineThickness > 1 ? int(m_lineThickness / 2) : 1;
147 if (int(m_lineThickness) % 2 == 1)
148 adjustForThickness++;
149 RenderMathMLBlock* numerator = toRenderMathMLBlock(firstChild());
150 if (numerator->isRenderMathMLRow())
151 verticalOffset = numerator->offsetHeight() + adjustForThickness;
152 else
153 verticalOffset = numerator->offsetHeight();
154 }
155
156 tx += x();
157 ty += y() + verticalOffset;
158
159 GraphicsContextStateSaver stateSaver(*info.context);
160
161 info.context->setStrokeThickness(m_lineThickness);
162 info.context->setStrokeStyle(SolidStroke);
163 info.context->setStrokeColor(style()->visitedDependentColor(CSSPropertyColor), ColorSpaceSRGB);
164
165 info.context->drawLine(IntPoint(tx, ty), IntPoint(tx + offsetWidth(), ty));
166 }
167
baselinePosition(FontBaseline,bool firstLine,LineDirectionMode lineDirection,LinePositionMode linePositionMode) const168 int RenderMathMLFraction::baselinePosition(FontBaseline, bool firstLine, LineDirectionMode lineDirection, LinePositionMode linePositionMode) const
169 {
170 if (firstChild() && firstChild()->isRenderMathMLBlock()) {
171 RenderMathMLBlock* numerator = toRenderMathMLBlock(firstChild());
172 RenderStyle* refStyle = style();
173 if (previousSibling())
174 refStyle = previousSibling()->style();
175 else if (nextSibling())
176 refStyle = nextSibling()->style();
177 int shift = int(ceil((refStyle->fontMetrics().xHeight() + 1) / 2));
178 return numerator->offsetHeight() + shift;
179 }
180 return RenderBlock::baselinePosition(AlphabeticBaseline, firstLine, lineDirection, linePositionMode);
181 }
182
183 }
184
185
186 #endif // ENABLE(MATHML)
187