| File: | root/firefox-clang/obj-x86_64-pc-linux-gnu/layout/mathml/./../../../layout/mathml/nsMathMLmmultiscriptsFrame.cpp |
| Warning: | line 245, column 11 Value stored to 'trySupScriptShift' during its initialization is never read |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
| 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| 4 | |
| 5 | #include "nsMathMLmmultiscriptsFrame.h" |
| 6 | |
| 7 | #include <algorithm> |
| 8 | |
| 9 | #include "gfxContext.h" |
| 10 | #include "gfxMathTable.h" |
| 11 | #include "gfxTextRun.h" |
| 12 | #include "mozilla/PresShell.h" |
| 13 | #include "mozilla/StaticPrefs_mathml.h" |
| 14 | #include "mozilla/dom/Document.h" |
| 15 | #include "mozilla/dom/Element.h" |
| 16 | #include "nsLayoutUtils.h" |
| 17 | #include "nsPresContext.h" |
| 18 | |
| 19 | using namespace mozilla; |
| 20 | |
| 21 | // |
| 22 | // <mmultiscripts> -- attach prescripts and tensor indices to a base - |
| 23 | // implementation <msub> -- attach a subscript to a base - implementation |
| 24 | // <msubsup> -- attach a subscript-superscript pair to a base - implementation |
| 25 | // <msup> -- attach a superscript to a base - implementation |
| 26 | // |
| 27 | |
| 28 | nsIFrame* NS_NewMathMLmmultiscriptsFrame(PresShell* aPresShell, |
| 29 | ComputedStyle* aStyle) { |
| 30 | return new (aPresShell) |
| 31 | nsMathMLmmultiscriptsFrame(aStyle, aPresShell->GetPresContext()); |
| 32 | } |
| 33 | |
| 34 | NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmmultiscriptsFrame)void* nsMathMLmmultiscriptsFrame ::operator new(size_t sz, mozilla ::PresShell * aShell) { return aShell->AllocateFrame(nsQueryFrame ::nsMathMLmmultiscriptsFrame_id, sz); } |
| 35 | |
| 36 | nsMathMLmmultiscriptsFrame::~nsMathMLmmultiscriptsFrame() = default; |
| 37 | |
| 38 | uint8_t nsMathMLmmultiscriptsFrame::ScriptIncrement(nsIFrame* aFrame) { |
| 39 | if (!aFrame) { |
| 40 | return 0; |
| 41 | } |
| 42 | if (mFrames.ContainsFrame(aFrame)) { |
| 43 | if (mFrames.FirstChild() == aFrame || |
| 44 | aFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts)) { |
| 45 | return 0; // No script increment for base frames or prescript markers |
| 46 | } |
| 47 | return 1; |
| 48 | } |
| 49 | return 0; // not a child |
| 50 | } |
| 51 | |
| 52 | NS_IMETHODIMPnsresult |
| 53 | nsMathMLmmultiscriptsFrame::TransmitAutomaticData() { |
| 54 | // if our base is an embellished operator, let its state bubble to us |
| 55 | mPresentationData.baseFrame = mFrames.FirstChild(); |
| 56 | GetEmbellishDataFrom(mPresentationData.baseFrame, mEmbellishData); |
| 57 | |
| 58 | int32_t count = 0; |
| 59 | bool isSubScript = !mContent->IsMathMLElement(nsGkAtoms::msup); |
| 60 | |
| 61 | nsIFrame* childFrame = mFrames.FirstChild(); |
| 62 | while (childFrame) { |
| 63 | if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts)) { |
| 64 | // mprescripts frame |
| 65 | } else if (0 == count) { |
| 66 | // base frame |
| 67 | } else { |
| 68 | // super/subscript block |
| 69 | PropagateFrameFlagFor(childFrame, NS_FRAME_MATHML_SCRIPT_DESCENDANT); |
| 70 | isSubScript = !isSubScript; |
| 71 | } |
| 72 | count++; |
| 73 | childFrame = childFrame->GetNextSibling(); |
| 74 | } |
| 75 | |
| 76 | return NS_OK; |
| 77 | } |
| 78 | |
| 79 | /* virtual */ |
| 80 | void nsMathMLmmultiscriptsFrame::Place(DrawTarget* aDrawTarget, |
| 81 | const PlaceFlags& aFlags, |
| 82 | ReflowOutput& aDesiredSize) { |
| 83 | nscoord subScriptShift = 0; |
| 84 | nscoord supScriptShift = 0; |
| 85 | float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this); |
| 86 | |
| 87 | return PlaceMultiScript(PresContext(), aDrawTarget, aFlags, aDesiredSize, |
| 88 | this, subScriptShift, supScriptShift, |
| 89 | fontSizeInflation); |
| 90 | } |
| 91 | |
| 92 | // exported routine that both munderover and mmultiscripts share. |
| 93 | // munderover uses this when movablelimits is set. |
| 94 | void nsMathMLmmultiscriptsFrame::PlaceMultiScript( |
| 95 | nsPresContext* aPresContext, DrawTarget* aDrawTarget, |
| 96 | const PlaceFlags& aFlags, ReflowOutput& aDesiredSize, |
| 97 | nsMathMLContainerFrame* aFrame, nscoord aUserSubScriptShift, |
| 98 | nscoord aUserSupScriptShift, float aFontSizeInflation) { |
| 99 | nsAtom* tag = aFrame->GetContent()->NodeInfo()->NameAtom(); |
| 100 | |
| 101 | // This function deals with both munderover etc. as well as msubsup etc. |
| 102 | // As the former behaves identically to the later, we treat it as such |
| 103 | // to avoid additional checks later. |
| 104 | if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::mover)) { |
| 105 | tag = nsGkAtoms::msup; |
| 106 | } else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munder)) { |
| 107 | tag = nsGkAtoms::msub; |
| 108 | } else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munderover)) { |
| 109 | tag = nsGkAtoms::msubsup; |
| 110 | } |
| 111 | |
| 112 | nsBoundingMetrics bmFrame; |
| 113 | |
| 114 | nscoord minShiftFromXHeight, subDrop, supDrop; |
| 115 | |
| 116 | //////////////////////////////////////// |
| 117 | // Initialize super/sub shifts that |
| 118 | // depend only on the current font |
| 119 | //////////////////////////////////////// |
| 120 | |
| 121 | nsIFrame* baseFrame = aFrame->PrincipalChildList().FirstChild(); |
| 122 | |
| 123 | if (!baseFrame) { |
| 124 | if (tag == nsGkAtoms::mmultiscripts) { |
| 125 | aFrame->ReportErrorToConsole("NoBase"); |
| 126 | } else { |
| 127 | aFrame->ReportChildCountError(); |
| 128 | } |
| 129 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
| 130 | } |
| 131 | |
| 132 | // get x-height (an ex) |
| 133 | const nsStyleFont* font = aFrame->StyleFont(); |
| 134 | RefPtr<nsFontMetrics> fm = |
| 135 | nsLayoutUtils::GetFontMetricsForFrame(baseFrame, aFontSizeInflation); |
| 136 | |
| 137 | nscoord xHeight = fm->XHeight(); |
| 138 | |
| 139 | nscoord oneDevPixel = fm->AppUnitsPerDevPixel(); |
| 140 | RefPtr<gfxFont> mathFont = fm->GetThebesFontGroup()->GetFirstMathFont(); |
| 141 | // scriptspace from TeX for extra spacing after sup/subscript |
| 142 | nscoord scriptSpace; |
| 143 | if (mathFont) { |
| 144 | scriptSpace = mathFont->MathTable()->Constant( |
| 145 | gfxMathTable::SpaceAfterScript, oneDevPixel); |
| 146 | } else { |
| 147 | // (0.5pt in plain TeX) |
| 148 | scriptSpace = nsPresContext::CSSPointsToAppUnits(0.5f); |
| 149 | } |
| 150 | |
| 151 | // Try and read sub and sup drops from the MATH table. |
| 152 | if (mathFont) { |
| 153 | subDrop = mathFont->MathTable()->Constant( |
| 154 | gfxMathTable::SubscriptBaselineDropMin, oneDevPixel); |
| 155 | supDrop = mathFont->MathTable()->Constant( |
| 156 | gfxMathTable::SuperscriptBaselineDropMax, oneDevPixel); |
| 157 | } |
| 158 | |
| 159 | // force the scriptSpace to be at least 1 pixel |
| 160 | nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1); |
| 161 | scriptSpace = std::max(onePixel, scriptSpace); |
| 162 | |
| 163 | ///////////////////////////////////// |
| 164 | // first the shift for the subscript |
| 165 | |
| 166 | nscoord subScriptShift; |
| 167 | if (mathFont) { |
| 168 | // Try and get the sub script shift from the MATH table. Note that contrary |
| 169 | // to TeX we only have one parameter. |
| 170 | subScriptShift = mathFont->MathTable()->Constant( |
| 171 | gfxMathTable::SubscriptShiftDown, oneDevPixel); |
| 172 | } else { |
| 173 | // subScriptShift{1,2} |
| 174 | // = minimum amount to shift the subscript down |
| 175 | // = sub{1,2} in TeXbook |
| 176 | // subScriptShift1 = subscriptshift attribute * x-height |
| 177 | nscoord subScriptShift1, subScriptShift2; |
| 178 | // Get subScriptShift{1,2} default from font |
| 179 | GetSubScriptShifts(fm, subScriptShift1, subScriptShift2); |
| 180 | if (tag == nsGkAtoms::msub) { |
| 181 | subScriptShift = subScriptShift1; |
| 182 | } else { |
| 183 | subScriptShift = std::max(subScriptShift1, subScriptShift2); |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | if (0 < aUserSubScriptShift) { |
| 188 | // the user has set the subscriptshift attribute |
| 189 | subScriptShift = std::max(subScriptShift, aUserSubScriptShift); |
| 190 | } |
| 191 | |
| 192 | ///////////////////////////////////// |
| 193 | // next the shift for the superscript |
| 194 | |
| 195 | nscoord supScriptShift; |
| 196 | nsPresentationData presentationData; |
| 197 | aFrame->GetPresentationData(presentationData); |
| 198 | bool compressed = font->mMathShift == StyleMathShift::Compact; |
| 199 | if (mathFont) { |
| 200 | // Try and get the super script shift from the MATH table. Note that |
| 201 | // contrary to TeX we only have two parameters. |
| 202 | supScriptShift = mathFont->MathTable()->Constant( |
| 203 | compressed ? gfxMathTable::SuperscriptShiftUpCramped |
| 204 | : gfxMathTable::SuperscriptShiftUp, |
| 205 | oneDevPixel); |
| 206 | } else { |
| 207 | // supScriptShift{1,2,3} |
| 208 | // = minimum amount to shift the supscript up |
| 209 | // = sup{1,2,3} in TeX |
| 210 | // supScriptShift1 = superscriptshift attribute * x-height |
| 211 | // Note that there are THREE values for supscript shifts depending |
| 212 | // on the current style |
| 213 | nscoord supScriptShift1, supScriptShift2, supScriptShift3; |
| 214 | // Set supScriptShift{1,2,3} default from font |
| 215 | GetSupScriptShifts(fm, supScriptShift1, supScriptShift2, supScriptShift3); |
| 216 | |
| 217 | // get sup script shift depending on current script level and display style |
| 218 | // Rule 18c, App. G, TeXbook |
| 219 | if (font->mMathDepth == 0 && font->mMathStyle == StyleMathStyle::Normal && |
| 220 | !compressed) { |
| 221 | // Style D in TeXbook |
| 222 | supScriptShift = supScriptShift1; |
| 223 | } else if (compressed) { |
| 224 | // Style C' in TeXbook = D',T',S',SS' |
| 225 | supScriptShift = supScriptShift3; |
| 226 | } else { |
| 227 | // everything else = T,S,SS |
| 228 | supScriptShift = supScriptShift2; |
| 229 | } |
| 230 | } |
| 231 | |
| 232 | if (0 < aUserSupScriptShift) { |
| 233 | // the user has set the supscriptshift attribute |
| 234 | supScriptShift = std::max(supScriptShift, aUserSupScriptShift); |
| 235 | } |
| 236 | |
| 237 | //////////////////////////////////// |
| 238 | // Get the children's sizes |
| 239 | //////////////////////////////////// |
| 240 | |
| 241 | const WritingMode wm(aDesiredSize.GetWritingMode()); |
| 242 | nscoord width = 0, prescriptsWidth = 0, rightBearing = 0; |
| 243 | nscoord minSubScriptShift = 0, minSupScriptShift = 0; |
| 244 | nscoord trySubScriptShift = subScriptShift; |
| 245 | nscoord trySupScriptShift = supScriptShift; |
Value stored to 'trySupScriptShift' during its initialization is never read | |
| 246 | nscoord maxSubScriptShift = subScriptShift; |
| 247 | nscoord maxSupScriptShift = supScriptShift; |
| 248 | ReflowOutput baseSize(wm); |
| 249 | ReflowOutput subScriptSize(wm); |
| 250 | ReflowOutput supScriptSize(wm); |
| 251 | ReflowOutput multiSubSize(wm), multiSupSize(wm); |
| 252 | baseFrame = nullptr; |
| 253 | nsIFrame* subScriptFrame = nullptr; |
| 254 | nsIFrame* supScriptFrame = nullptr; |
| 255 | nsIFrame* prescriptsFrame = nullptr; // frame of <mprescripts/>, if there. |
| 256 | |
| 257 | bool firstPrescriptsPair = false; |
| 258 | nsBoundingMetrics bmBase, bmSubScript, bmSupScript, bmMultiSub, bmMultiSup; |
| 259 | nsMargin baseMargin, subScriptMargin, supScriptMargin; |
| 260 | multiSubSize.SetBlockStartAscent(-0x7FFFFFFF); |
| 261 | multiSupSize.SetBlockStartAscent(-0x7FFFFFFF); |
| 262 | bmMultiSub.ascent = bmMultiSup.ascent = -0x7FFFFFFF; |
| 263 | bmMultiSub.descent = bmMultiSup.descent = -0x7FFFFFFF; |
| 264 | nscoord italicCorrection = 0; |
| 265 | nscoord largeOpItalicCorrection = 0; |
| 266 | |
| 267 | nsBoundingMetrics boundingMetrics; |
| 268 | boundingMetrics.width = 0; |
| 269 | boundingMetrics.ascent = boundingMetrics.descent = -0x7FFFFFFF; |
| 270 | aDesiredSize.Width() = aDesiredSize.Height() = 0; |
| 271 | |
| 272 | int32_t count = 0; |
| 273 | |
| 274 | // Boolean to determine whether the current child is a subscript. |
| 275 | // Note that only msup starts with a superscript. |
| 276 | bool isSubScript = (tag != nsGkAtoms::msup); |
| 277 | |
| 278 | nsIFrame* childFrame = aFrame->PrincipalChildList().FirstChild(); |
| 279 | while (childFrame) { |
| 280 | if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts)) { |
| 281 | if (tag != nsGkAtoms::mmultiscripts) { |
| 282 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
| 283 | aFrame->ReportInvalidChildError(nsGkAtoms::mprescripts); |
| 284 | } |
| 285 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
| 286 | } |
| 287 | if (prescriptsFrame) { |
| 288 | // duplicate <mprescripts/> found |
| 289 | // report an error, encourage people to get their markups in order |
| 290 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
| 291 | aFrame->ReportErrorToConsole("DuplicateMprescripts"); |
| 292 | } |
| 293 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
| 294 | } |
| 295 | if (!isSubScript) { |
| 296 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
| 297 | aFrame->ReportErrorToConsole("SubSupMismatch"); |
| 298 | } |
| 299 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
| 300 | } |
| 301 | |
| 302 | prescriptsFrame = childFrame; |
| 303 | firstPrescriptsPair = true; |
| 304 | } else if (0 == count) { |
| 305 | // base |
| 306 | baseFrame = childFrame; |
| 307 | GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase); |
| 308 | baseMargin = GetMarginForPlace(aFlags, baseFrame); |
| 309 | |
| 310 | if (tag != nsGkAtoms::msub) { |
| 311 | // Apply italics correction if there is the potential for a |
| 312 | // postsupscript. |
| 313 | GetItalicCorrection(bmBase, italicCorrection); |
| 314 | // If italics correction is applied, we always add "a little to spare" |
| 315 | // (see TeXbook Ch.11, p.64), as we estimate the italic creation |
| 316 | // ourselves and it isn't the same as TeX. |
| 317 | italicCorrection += onePixel; |
| 318 | } |
| 319 | |
| 320 | if (tag != nsGkAtoms::msup) { |
| 321 | // If the base is a largeop, determine its italic correction. |
| 322 | // https://w3c.github.io/mathml-core/#base-with-subscript |
| 323 | if (nsIMathMLFrame* mathMLFrame = do_QueryFrame(baseFrame)) { |
| 324 | nsEmbellishData baseFrameEmbellishData; |
| 325 | mathMLFrame->GetEmbellishData(baseFrameEmbellishData); |
| 326 | if (baseFrameEmbellishData.flags.contains( |
| 327 | MathMLEmbellishFlag::LargeOp)) { |
| 328 | largeOpItalicCorrection = mathMLFrame->ItalicCorrection(); |
| 329 | } |
| 330 | } |
| 331 | } |
| 332 | |
| 333 | // we update boundingMetrics.{ascent,descent} with that |
| 334 | // of the baseFrame only after processing all the sup/sub pairs |
| 335 | boundingMetrics.width = bmBase.width + baseMargin.LeftRight(); |
| 336 | boundingMetrics.rightBearing = |
| 337 | bmBase.rightBearing + baseMargin.LeftRight(); |
| 338 | boundingMetrics.leftBearing = bmBase.leftBearing; // until overwritten |
| 339 | } else { |
| 340 | // super/subscript block |
| 341 | if (isSubScript) { |
| 342 | // subscript |
| 343 | subScriptFrame = childFrame; |
| 344 | GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, |
| 345 | bmSubScript); |
| 346 | subScriptMargin = GetMarginForPlace(aFlags, subScriptFrame); |
| 347 | |
| 348 | if (!mathFont) { |
| 349 | // get the subdrop from the subscript font |
| 350 | GetSubDropFromChild(subScriptFrame, subDrop, aFontSizeInflation); |
| 351 | } |
| 352 | |
| 353 | // parameter v, Rule 18a, App. G, TeXbook |
| 354 | minSubScriptShift = bmBase.descent + baseMargin.bottom + subDrop; |
| 355 | trySubScriptShift = std::max(minSubScriptShift, subScriptShift); |
| 356 | multiSubSize.SetBlockStartAscent( |
| 357 | std::max(multiSubSize.BlockStartAscent(), |
| 358 | subScriptSize.BlockStartAscent() + subScriptMargin.top)); |
| 359 | bmMultiSub.ascent = std::max(bmMultiSub.ascent, |
| 360 | bmSubScript.ascent + subScriptMargin.top); |
| 361 | bmMultiSub.descent = std::max( |
| 362 | bmMultiSub.descent, bmSubScript.descent + subScriptMargin.bottom); |
| 363 | multiSubSize.Height() = |
| 364 | std::max(multiSubSize.Height(), |
| 365 | subScriptSize.Height() - subScriptSize.BlockStartAscent() + |
| 366 | subScriptMargin.bottom); |
| 367 | if (bmSubScript.width) { |
| 368 | width = bmSubScript.width + subScriptMargin.LeftRight() + scriptSpace; |
| 369 | } |
| 370 | rightBearing = bmSubScript.rightBearing + subScriptMargin.LeftRight(); |
| 371 | |
| 372 | if (tag == nsGkAtoms::msub) { |
| 373 | boundingMetrics.rightBearing = boundingMetrics.width + rightBearing; |
| 374 | boundingMetrics.width += width; |
| 375 | |
| 376 | nscoord subscriptTopMax; |
| 377 | if (mathFont) { |
| 378 | subscriptTopMax = mathFont->MathTable()->Constant( |
| 379 | gfxMathTable::SubscriptTopMax, oneDevPixel); |
| 380 | } else { |
| 381 | // get min subscript shift limit from x-height |
| 382 | // = h(x) - 4/5 * sigma_5, Rule 18b, App. G, TeXbook |
| 383 | subscriptTopMax = NSToCoordRound((4.0f / 5.0f) * xHeight); |
| 384 | } |
| 385 | nscoord minShiftFromXHeight = |
| 386 | bmSubScript.ascent + subScriptMargin.top - subscriptTopMax; |
| 387 | maxSubScriptShift = std::max(trySubScriptShift, minShiftFromXHeight); |
| 388 | |
| 389 | maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift); |
| 390 | trySubScriptShift = subScriptShift; |
| 391 | } |
| 392 | } else { |
| 393 | // supscript |
| 394 | supScriptFrame = childFrame; |
| 395 | GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, |
| 396 | bmSupScript); |
| 397 | supScriptMargin = GetMarginForPlace(aFlags, supScriptFrame); |
| 398 | if (!mathFont) { |
| 399 | // get the supdrop from the supscript font |
| 400 | GetSupDropFromChild(supScriptFrame, supDrop, aFontSizeInflation); |
| 401 | } |
| 402 | // parameter u, Rule 18a, App. G, TeXbook |
| 403 | minSupScriptShift = bmBase.ascent + baseMargin.top - supDrop; |
| 404 | nscoord superscriptBottomMin; |
| 405 | if (mathFont) { |
| 406 | superscriptBottomMin = mathFont->MathTable()->Constant( |
| 407 | gfxMathTable::SuperscriptBottomMin, oneDevPixel); |
| 408 | } else { |
| 409 | // get min supscript shift limit from x-height |
| 410 | // = d(x) + 1/4 * sigma_5, Rule 18c, App. G, TeXbook |
| 411 | superscriptBottomMin = NSToCoordRound((1.0f / 4.0f) * xHeight); |
| 412 | } |
| 413 | minShiftFromXHeight = |
| 414 | bmSupScript.descent + supScriptMargin.bottom + superscriptBottomMin; |
| 415 | trySupScriptShift = std::max( |
| 416 | minSupScriptShift, std::max(minShiftFromXHeight, supScriptShift)); |
| 417 | multiSupSize.SetBlockStartAscent( |
| 418 | std::max(multiSupSize.BlockStartAscent(), |
| 419 | supScriptSize.BlockStartAscent() + supScriptMargin.top)); |
| 420 | bmMultiSup.ascent = std::max(bmMultiSup.ascent, |
| 421 | bmSupScript.ascent + supScriptMargin.top); |
| 422 | bmMultiSup.descent = std::max( |
| 423 | bmMultiSup.descent, bmSupScript.descent + supScriptMargin.bottom); |
| 424 | multiSupSize.Height() = |
| 425 | std::max(multiSupSize.Height(), |
| 426 | supScriptSize.Height() - supScriptSize.BlockStartAscent() + |
| 427 | supScriptMargin.bottom); |
| 428 | |
| 429 | if (bmSupScript.width) { |
| 430 | width = |
| 431 | std::max(width, bmSupScript.width + supScriptMargin.LeftRight() + |
| 432 | scriptSpace); |
| 433 | } |
| 434 | |
| 435 | if (!prescriptsFrame) { // we are still looping over base & postscripts |
| 436 | rightBearing = std::max(rightBearing, |
| 437 | italicCorrection + bmSupScript.rightBearing + |
| 438 | supScriptMargin.LeftRight()); |
| 439 | boundingMetrics.rightBearing = boundingMetrics.width + rightBearing; |
| 440 | boundingMetrics.width += width; |
| 441 | } else { |
| 442 | prescriptsWidth += width; |
| 443 | if (firstPrescriptsPair) { |
| 444 | firstPrescriptsPair = false; |
| 445 | boundingMetrics.leftBearing = |
| 446 | std::min(bmSubScript.leftBearing, bmSupScript.leftBearing); |
| 447 | } |
| 448 | } |
| 449 | width = rightBearing = 0; |
| 450 | |
| 451 | // negotiate between the various shifts so that |
| 452 | // there is enough gap between the sup and subscripts |
| 453 | // Rule 18e, App. G, TeXbook |
| 454 | if (tag == nsGkAtoms::mmultiscripts || tag == nsGkAtoms::msubsup) { |
| 455 | nscoord subSuperscriptGapMin; |
| 456 | if (mathFont) { |
| 457 | subSuperscriptGapMin = mathFont->MathTable()->Constant( |
| 458 | gfxMathTable::SubSuperscriptGapMin, oneDevPixel); |
| 459 | } else { |
| 460 | nscoord ruleSize; |
| 461 | GetRuleThickness(aDrawTarget, fm, ruleSize); |
| 462 | subSuperscriptGapMin = 4 * ruleSize; |
| 463 | } |
| 464 | nscoord gap = |
| 465 | (trySupScriptShift - bmSupScript.descent - |
| 466 | supScriptMargin.bottom) - |
| 467 | (subScriptMargin.top + bmSubScript.ascent - trySubScriptShift); |
| 468 | if (gap < subSuperscriptGapMin) { |
| 469 | // adjust trySubScriptShift to get a gap of subSuperscriptGapMin |
| 470 | trySubScriptShift += subSuperscriptGapMin - gap; |
| 471 | } |
| 472 | |
| 473 | // next we want to ensure that the bottom of the superscript |
| 474 | // will be > superscriptBottomMaxWithSubscript |
| 475 | nscoord superscriptBottomMaxWithSubscript; |
| 476 | if (mathFont) { |
| 477 | superscriptBottomMaxWithSubscript = mathFont->MathTable()->Constant( |
| 478 | gfxMathTable::SuperscriptBottomMaxWithSubscript, oneDevPixel); |
| 479 | } else { |
| 480 | superscriptBottomMaxWithSubscript = |
| 481 | NSToCoordRound((4.0f / 5.0f) * xHeight); |
| 482 | } |
| 483 | gap = superscriptBottomMaxWithSubscript - |
| 484 | (trySupScriptShift - bmSupScript.descent - |
| 485 | supScriptMargin.bottom); |
| 486 | if (gap > 0) { |
| 487 | trySupScriptShift += gap; |
| 488 | trySubScriptShift -= gap; |
| 489 | } |
| 490 | } |
| 491 | |
| 492 | maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift); |
| 493 | maxSupScriptShift = std::max(maxSupScriptShift, trySupScriptShift); |
| 494 | |
| 495 | trySubScriptShift = subScriptShift; |
| 496 | trySupScriptShift = supScriptShift; |
| 497 | } |
| 498 | |
| 499 | isSubScript = !isSubScript; |
| 500 | } |
| 501 | count++; |
| 502 | childFrame = childFrame->GetNextSibling(); |
| 503 | } |
| 504 | |
| 505 | // NoBase error may also have been reported above |
| 506 | if ((count != 2 && (tag == nsGkAtoms::msup || tag == nsGkAtoms::msub)) || |
| 507 | (count != 3 && tag == nsGkAtoms::msubsup) || !baseFrame || |
| 508 | (!isSubScript && tag == nsGkAtoms::mmultiscripts)) { |
| 509 | // report an error, encourage people to get their markups in order |
| 510 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
| 511 | if ((count != 2 && (tag == nsGkAtoms::msup || tag == nsGkAtoms::msub)) || |
| 512 | (count != 3 && tag == nsGkAtoms::msubsup)) { |
| 513 | aFrame->ReportChildCountError(); |
| 514 | } else if (!baseFrame) { |
| 515 | aFrame->ReportErrorToConsole("NoBase"); |
| 516 | } else { |
| 517 | aFrame->ReportErrorToConsole("SubSupMismatch"); |
| 518 | } |
| 519 | } |
| 520 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
| 521 | } |
| 522 | |
| 523 | // we left out the width of prescripts, so ... |
| 524 | boundingMetrics.rightBearing += prescriptsWidth; |
| 525 | boundingMetrics.width += prescriptsWidth; |
| 526 | |
| 527 | // Zero out the shifts in where a frame isn't present to avoid the potential |
| 528 | // for overflow. |
| 529 | if (!subScriptFrame) { |
| 530 | maxSubScriptShift = 0; |
| 531 | } |
| 532 | if (!supScriptFrame) { |
| 533 | maxSupScriptShift = 0; |
| 534 | } |
| 535 | |
| 536 | // we left out the base during our bounding box updates, so ... |
| 537 | if (tag == nsGkAtoms::msub) { |
| 538 | boundingMetrics.ascent = std::max(bmBase.ascent + baseMargin.top, |
| 539 | bmMultiSub.ascent - maxSubScriptShift); |
| 540 | } else { |
| 541 | boundingMetrics.ascent = std::max(bmBase.ascent + baseMargin.top, |
| 542 | (bmMultiSup.ascent + maxSupScriptShift)); |
| 543 | } |
| 544 | if (tag == nsGkAtoms::msup) { |
| 545 | boundingMetrics.descent = std::max(bmBase.descent + baseMargin.bottom, |
| 546 | bmMultiSup.descent - maxSupScriptShift); |
| 547 | } else { |
| 548 | boundingMetrics.descent = |
| 549 | std::max(bmBase.descent + baseMargin.bottom, |
| 550 | (bmMultiSub.descent + maxSubScriptShift)); |
| 551 | } |
| 552 | |
| 553 | // get the reflow metrics ... |
| 554 | aDesiredSize.SetBlockStartAscent( |
| 555 | std::max(baseSize.BlockStartAscent() + baseMargin.top, |
| 556 | std::max(multiSubSize.BlockStartAscent() - maxSubScriptShift, |
| 557 | multiSupSize.BlockStartAscent() + maxSupScriptShift))); |
| 558 | aDesiredSize.Height() = |
| 559 | aDesiredSize.BlockStartAscent() + |
| 560 | std::max( |
| 561 | baseSize.Height() - baseSize.BlockStartAscent() + baseMargin.bottom, |
| 562 | std::max(multiSubSize.Height() + maxSubScriptShift, |
| 563 | multiSupSize.Height() - maxSupScriptShift)); |
| 564 | aDesiredSize.Width() = boundingMetrics.width; |
| 565 | aDesiredSize.mBoundingMetrics = boundingMetrics; |
| 566 | |
| 567 | // Apply width/height to math content box. |
| 568 | auto sizes = aFrame->GetWidthAndHeightForPlaceAdjustment(aFlags); |
| 569 | aFrame->ApplyAdjustmentForWidthAndHeight(aFlags, sizes, aDesiredSize, |
| 570 | boundingMetrics); |
| 571 | |
| 572 | // Add padding+border. |
| 573 | auto borderPadding = aFrame->GetBorderPaddingForPlace(aFlags); |
| 574 | InflateReflowAndBoundingMetrics(borderPadding, aDesiredSize, boundingMetrics); |
| 575 | |
| 576 | aFrame->SetBoundingMetrics(boundingMetrics); |
| 577 | aFrame->SetReference(nsPoint(0, aDesiredSize.BlockStartAscent())); |
| 578 | |
| 579 | ////////////////// |
| 580 | // Place Children |
| 581 | |
| 582 | // Place prescripts, followed by base, and then postscripts. |
| 583 | // The list of frames is in the order: {base} {postscripts} {prescripts} |
| 584 | // We go over the list in a circular manner, starting at <prescripts/> |
| 585 | |
| 586 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
| 587 | const bool isRTL = aFrame->GetWritingMode().IsBidiRTL(); |
| 588 | nscoord dx = isRTL ? borderPadding.right : borderPadding.left; |
| 589 | nscoord dy = 0; |
| 590 | |
| 591 | // With msub and msup there is only one element and |
| 592 | // subscriptFrame/supScriptFrame have already been set above where |
| 593 | // relevant. In these cases we skip to the reflow part. |
| 594 | if (tag == nsGkAtoms::msub || tag == nsGkAtoms::msup) { |
| 595 | count = 1; |
| 596 | } else { |
| 597 | count = 0; |
| 598 | } |
| 599 | childFrame = prescriptsFrame; |
| 600 | bool isPreScript = true; |
| 601 | do { |
| 602 | if (!childFrame) { // end of prescripts, |
| 603 | isPreScript = false; |
| 604 | // place the base ... |
| 605 | childFrame = baseFrame; |
| 606 | dy = aDesiredSize.BlockStartAscent() - baseSize.BlockStartAscent(); |
| 607 | baseMargin = GetMarginForPlace(aFlags, baseFrame); |
| 608 | nscoord dx_base = dx + (isRTL ? baseMargin.right : baseMargin.left); |
| 609 | FinishReflowChild(baseFrame, aPresContext, baseSize, nullptr, |
| 610 | aFrame->MirrorIfRTL(aDesiredSize.Width(), |
| 611 | baseSize.Width(), dx_base), |
| 612 | dy, ReflowChildFlags::Default); |
| 613 | if (prescriptsFrame) { |
| 614 | // place the <mprescripts/> |
| 615 | ReflowOutput prescriptsSize(wm); |
| 616 | nsBoundingMetrics unusedBm; |
| 617 | GetReflowAndBoundingMetricsFor(prescriptsFrame, prescriptsSize, |
| 618 | unusedBm); |
| 619 | nsMargin prescriptsMargin = |
| 620 | GetMarginForPlace(aFlags, prescriptsFrame); |
| 621 | nscoord dx_prescripts = |
| 622 | dx + (isRTL ? prescriptsMargin.right : prescriptsMargin.left); |
| 623 | dy = aDesiredSize.BlockStartAscent() - |
| 624 | prescriptsSize.BlockStartAscent(); |
| 625 | FinishReflowChild( |
| 626 | prescriptsFrame, aPresContext, prescriptsSize, nullptr, |
| 627 | aFrame->MirrorIfRTL(aDesiredSize.Width(), prescriptsSize.Width(), |
| 628 | dx_prescripts), |
| 629 | dy, ReflowChildFlags::Default); |
| 630 | } |
| 631 | dx += bmBase.width + baseMargin.LeftRight(); |
| 632 | } else if (childFrame != prescriptsFrame) { |
| 633 | // process each sup/sub pair |
| 634 | if (0 == count) { |
| 635 | subScriptFrame = childFrame; |
| 636 | count = 1; |
| 637 | } else if (1 == count) { |
| 638 | if (tag != nsGkAtoms::msub) { |
| 639 | supScriptFrame = childFrame; |
| 640 | } |
| 641 | count = 0; |
| 642 | |
| 643 | // get the ascent/descent of sup/subscripts stored in their rects |
| 644 | // rect.x = descent, rect.y = ascent |
| 645 | if (subScriptFrame) { |
| 646 | GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, |
| 647 | bmSubScript); |
| 648 | subScriptMargin = GetMarginForPlace(aFlags, subScriptFrame); |
| 649 | } |
| 650 | if (supScriptFrame) { |
| 651 | GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, |
| 652 | bmSupScript); |
| 653 | supScriptMargin = GetMarginForPlace(aFlags, supScriptFrame); |
| 654 | } |
| 655 | |
| 656 | width = std::max(subScriptSize.Width() + subScriptMargin.LeftRight(), |
| 657 | supScriptSize.Width() + supScriptMargin.LeftRight()); |
| 658 | |
| 659 | if (subScriptFrame) { |
| 660 | nscoord x = |
| 661 | dx + (isRTL ? subScriptMargin.right : subScriptMargin.left); |
| 662 | // prescripts should be right aligned |
| 663 | // https://bugzilla.mozilla.org/show_bug.cgi?id=928675 |
| 664 | if (isPreScript) { |
| 665 | x += width - subScriptSize.Width() - subScriptMargin.LeftRight(); |
| 666 | } else { |
| 667 | // post subscripts are shifted by the largeOpItalicCorrection |
| 668 | // value. |
| 669 | x -= largeOpItalicCorrection; |
| 670 | } |
| 671 | dy = aDesiredSize.BlockStartAscent() - |
| 672 | subScriptSize.BlockStartAscent() + maxSubScriptShift; |
| 673 | FinishReflowChild(subScriptFrame, aPresContext, subScriptSize, |
| 674 | nullptr, |
| 675 | aFrame->MirrorIfRTL(aDesiredSize.Width(), |
| 676 | subScriptSize.Width(), x), |
| 677 | dy, ReflowChildFlags::Default); |
| 678 | } |
| 679 | |
| 680 | if (supScriptFrame) { |
| 681 | nscoord x = |
| 682 | dx + (isRTL ? supScriptMargin.right : supScriptMargin.left); |
| 683 | if (isPreScript) { |
| 684 | x += width - supScriptSize.Width() - supScriptMargin.LeftRight(); |
| 685 | } else { |
| 686 | // post superscripts are shifted by the italic correction value |
| 687 | x += italicCorrection; |
| 688 | } |
| 689 | dy = aDesiredSize.BlockStartAscent() - |
| 690 | supScriptSize.BlockStartAscent() - maxSupScriptShift; |
| 691 | FinishReflowChild(supScriptFrame, aPresContext, supScriptSize, |
| 692 | nullptr, |
| 693 | aFrame->MirrorIfRTL(aDesiredSize.Width(), |
| 694 | supScriptSize.Width(), x), |
| 695 | dy, ReflowChildFlags::Default); |
| 696 | } |
| 697 | dx += width + scriptSpace; |
| 698 | } |
| 699 | } |
| 700 | childFrame = childFrame->GetNextSibling(); |
| 701 | } while (prescriptsFrame != childFrame); |
| 702 | } |
| 703 | } |