1/* 2 * Copyright (C) 2009 Alex Milowski (alex@milowski.com). All rights reserved. 3 * Copyright (C) 2012 David Barton (dbarton@mathscribe.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 "RenderMathMLBlock.h" 32 33#include "GraphicsContext.h" 34#include "MathMLNames.h" 35#include "RenderView.h" 36#include <wtf/text/StringBuilder.h> 37 38#if ENABLE(DEBUG_MATH_LAYOUT) 39#include "PaintInfo.h" 40#endif 41 42namespace WebCore { 43 44using namespace MathMLNames; 45 46RenderMathMLBlock::RenderMathMLBlock(Element& container, PassRef<RenderStyle> style) 47 : RenderFlexibleBox(container, WTF::move(style)) 48{ 49} 50 51RenderMathMLBlock::RenderMathMLBlock(Document& document, PassRef<RenderStyle> style) 52 : RenderFlexibleBox(document, WTF::move(style)) 53{ 54} 55 56bool RenderMathMLBlock::isChildAllowed(const RenderObject& child, const RenderStyle&) const 57{ 58 return child.node() && isElement(*child.node()); 59} 60 61RenderPtr<RenderMathMLBlock> RenderMathMLBlock::createAnonymousMathMLBlock() 62{ 63 RenderPtr<RenderMathMLBlock> newBlock = createRenderer<RenderMathMLBlock>(document(), RenderStyle::createAnonymousStyleWithDisplay(&style(), FLEX)); 64 newBlock->initializeStyle(); 65 return newBlock; 66} 67 68int RenderMathMLBlock::baselinePosition(FontBaseline baselineType, bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const 69{ 70 // mathml.css sets math { -webkit-line-box-contain: glyphs replaced; line-height: 0; }, so when linePositionMode == PositionOfInteriorLineBoxes we want to 71 // return 0 here to match our line-height. This matters when RootInlineBox::ascentAndDescentForBox is called on a RootInlineBox for an inline-block. 72 if (linePositionMode == PositionOfInteriorLineBoxes) 73 return 0; 74 75 LayoutUnit baseline = firstLineBaseline(); // FIXME: This may be unnecessary after flex baselines are implemented (https://bugs.webkit.org/show_bug.cgi?id=96188). 76 if (baseline != -1) 77 return baseline; 78 79 return RenderFlexibleBox::baselinePosition(baselineType, firstLine, direction, linePositionMode); 80} 81 82const char* RenderMathMLBlock::renderName() const 83{ 84 EDisplay display = style().display(); 85 if (display == FLEX) 86 return isAnonymous() ? "RenderMathMLBlock (anonymous, flex)" : "RenderMathMLBlock (flex)"; 87 if (display == INLINE_FLEX) 88 return isAnonymous() ? "RenderMathMLBlock (anonymous, inline-flex)" : "RenderMathMLBlock (inline-flex)"; 89 // |display| should be one of the above. 90 ASSERT_NOT_REACHED(); 91 return isAnonymous() ? "RenderMathMLBlock (anonymous)" : "RenderMathMLBlock"; 92} 93 94#if ENABLE(DEBUG_MATH_LAYOUT) 95void RenderMathMLBlock::paint(PaintInfo& info, const LayoutPoint& paintOffset) 96{ 97 RenderFlexibleBox::paint(info, paintOffset); 98 99 if (info.context->paintingDisabled() || info.phase != PaintPhaseForeground) 100 return; 101 102 IntPoint adjustedPaintOffset = roundedIntPoint(paintOffset + location()); 103 104 GraphicsContextStateSaver stateSaver(*info.context); 105 106 info.context->setStrokeThickness(1.0f); 107 info.context->setStrokeStyle(SolidStroke); 108 info.context->setStrokeColor(Color(0, 0, 255), ColorSpaceSRGB); 109 110 info.context->drawLine(adjustedPaintOffset, IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y())); 111 info.context->drawLine(IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y()), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight())); 112 info.context->drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight()), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight())); 113 info.context->drawLine(adjustedPaintOffset, IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + pixelSnappedOffsetHeight())); 114 115 int topStart = paddingTop(); 116 117 info.context->setStrokeColor(Color(0, 255, 0), ColorSpaceSRGB); 118 119 info.context->drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + topStart), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + topStart)); 120 121 int baseline = roundToInt(baselinePosition(AlphabeticBaseline, true, HorizontalLine)); 122 123 info.context->setStrokeColor(Color(255, 0, 0), ColorSpaceSRGB); 124 125 info.context->drawLine(IntPoint(adjustedPaintOffset.x(), adjustedPaintOffset.y() + baseline), IntPoint(adjustedPaintOffset.x() + pixelSnappedOffsetWidth(), adjustedPaintOffset.y() + baseline)); 126} 127#endif // ENABLE(DEBUG_MATH_LAYOUT) 128 129// 130// The MathML specification says: 131// (http://www.w3.org/TR/MathML/chapter2.html#fund.units) 132// 133// "Most presentation elements have attributes that accept values representing 134// lengths to be used for size, spacing or similar properties. The syntax of a 135// length is specified as 136// 137// number | number unit | namedspace 138// 139// There should be no space between the number and the unit of a length." 140// 141// "A trailing '%' represents a percent of the default value. The default 142// value, or how it is obtained, is listed in the table of attributes for each 143// element. [...] A number without a unit is intepreted as a multiple of the 144// default value." 145// 146// "The possible units in MathML are: 147// 148// Unit Description 149// em an em (font-relative unit traditionally used for horizontal lengths) 150// ex an ex (font-relative unit traditionally used for vertical lengths) 151// px pixels, or size of a pixel in the current display 152// in inches (1 inch = 2.54 centimeters) 153// cm centimeters 154// mm millimeters 155// pt points (1 point = 1/72 inch) 156// pc picas (1 pica = 12 points) 157// % percentage of default value" 158// 159// The numbers are defined that way: 160// - unsigned-number: "a string of decimal digits with up to one decimal point 161// (U+002E), representing a non-negative terminating decimal number (a type of 162// rational number)" 163// - number: "an optional prefix of '-' (U+002D), followed by an unsigned 164// number, representing a terminating decimal number (a type of rational 165// number)" 166// 167bool parseMathMLLength(const String& string, LayoutUnit& lengthValue, const RenderStyle* style, bool allowNegative) 168{ 169 String s = string.simplifyWhiteSpace(); 170 171 int stringLength = s.length(); 172 if (!stringLength) 173 return false; 174 175 if (parseMathMLNamedSpace(s, lengthValue, style, allowNegative)) 176 return true; 177 178 StringBuilder number; 179 String unit; 180 181 // This verifies whether the negative sign is there. 182 int i = 0; 183 UChar c = s[0]; 184 if (c == '-') { 185 number.append(c); 186 i++; 187 } 188 189 // This gathers up characters that make up the number. 190 bool gotDot = false; 191 for ( ; i < stringLength; i++) { 192 c = s[i]; 193 // The string is invalid if it contains two dots. 194 if (gotDot && c == '.') 195 return false; 196 if (c == '.') 197 gotDot = true; 198 else if (!isASCIIDigit(c)) { 199 unit = s.substring(i, stringLength - i); 200 // Some authors leave blanks before the unit, but that shouldn't 201 // be allowed, so don't simplifyWhitespace on 'unit'. 202 break; 203 } 204 number.append(c); 205 } 206 207 // Convert number to floating point 208 bool ok; 209 float floatValue = number.toString().toFloat(&ok); 210 if (!ok) 211 return false; 212 if (floatValue < 0 && !allowNegative) 213 return false; 214 215 if (unit.isEmpty()) { 216 // no explicit unit, this is a number that will act as a multiplier 217 lengthValue *= floatValue; 218 return true; 219 } 220 if (unit == "%") { 221 lengthValue *= floatValue / 100; 222 return true; 223 } 224 if (unit == "em") { 225 lengthValue = floatValue * style->font().size(); 226 return true; 227 } 228 if (unit == "ex") { 229 lengthValue = floatValue * style->fontMetrics().xHeight(); 230 return true; 231 } 232 if (unit == "px") { 233 lengthValue = floatValue; 234 return true; 235 } 236 if (unit == "pt") { 237 lengthValue = 4 * (floatValue / 3); 238 return true; 239 } 240 if (unit == "pc") { 241 lengthValue = 16 * floatValue; 242 return true; 243 } 244 if (unit == "in") { 245 lengthValue = 96 * floatValue; 246 return true; 247 } 248 if (unit == "cm") { 249 lengthValue = 96 * (floatValue / 2.54); 250 return true; 251 } 252 if (unit == "mm") { 253 lengthValue = 96 * (floatValue / 25.4); 254 return true; 255 } 256 257 // unexpected unit 258 return false; 259} 260 261bool parseMathMLNamedSpace(const String& string, LayoutUnit& lengthValue, const RenderStyle* style, bool allowNegative) 262{ 263 float length = 0; 264 // See if it is one of the namedspaces (ranging -7/18em, -6/18, ... 7/18em) 265 if (string == "veryverythinmathspace") 266 length = 1; 267 else if (string == "verythinmathspace") 268 length = 2; 269 else if (string == "thinmathspace") 270 length = 3; 271 else if (string == "mediummathspace") 272 length = 4; 273 else if (string == "thickmathspace") 274 length = 5; 275 else if (string == "verythickmathspace") 276 length = 6; 277 else if (string == "veryverythickmathspace") 278 length = 7; 279 else if (allowNegative) { 280 if (string == "negativeveryverythinmathspace") 281 length = -1; 282 else if (string == "negativeverythinmathspace") 283 length = -2; 284 else if (string == "negativethinmathspace") 285 length = -3; 286 else if (string == "negativemediummathspace") 287 length = -4; 288 else if (string == "negativethickmathspace") 289 length = -5; 290 else if (string == "negativeverythickmathspace") 291 length = -6; 292 else if (string == "negativeveryverythickmathspace") 293 length = -7; 294 } 295 if (length) { 296 lengthValue = length * style->font().size() / 18; 297 return true; 298 } 299 return false; 300} 301 302int RenderMathMLTable::firstLineBaseline() const 303{ 304 // In legal MathML, we'll have a MathML parent. That RenderFlexibleBox parent will use our firstLineBaseline() for baseline alignment, per 305 // http://dev.w3.org/csswg/css3-flexbox/#flex-baselines. We want to vertically center an <mtable>, such as a matrix. Essentially the whole <mtable> element fits on a 306 // single line, whose baseline gives this centering. This is different than RenderTable::firstLineBoxBaseline, which returns the baseline of the first row of a <table>. 307 return (logicalHeight() + style().fontMetrics().xHeight()) / 2; 308} 309 310} 311 312#endif 313