File: | var/lib/jenkins/workspace/firefox-scan-build/layout/mathml/nsMathMLmmultiscriptsFrame.cpp |
Warning: | line 494, column 9 Value stored to 'trySupScriptShift' is never read |
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1 | /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
2 | /* vim: set ts=8 sts=2 et sw=2 tw=80: */ |
3 | /* This Source Code Form is subject to the terms of the Mozilla Public |
4 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
5 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
6 | |
7 | #include "nsMathMLmmultiscriptsFrame.h" |
8 | |
9 | #include "mozilla/dom/Document.h" |
10 | #include "mozilla/dom/Element.h" |
11 | #include "mozilla/PresShell.h" |
12 | #include "mozilla/StaticPrefs_mathml.h" |
13 | #include "nsLayoutUtils.h" |
14 | #include "nsPresContext.h" |
15 | #include <algorithm> |
16 | #include "gfxContext.h" |
17 | #include "gfxMathTable.h" |
18 | #include "gfxTextRun.h" |
19 | |
20 | using namespace mozilla; |
21 | |
22 | // |
23 | // <mmultiscripts> -- attach prescripts and tensor indices to a base - |
24 | // implementation <msub> -- attach a subscript to a base - implementation |
25 | // <msubsup> -- attach a subscript-superscript pair to a base - implementation |
26 | // <msup> -- attach a superscript to a base - implementation |
27 | // |
28 | |
29 | nsIFrame* NS_NewMathMLmmultiscriptsFrame(PresShell* aPresShell, |
30 | ComputedStyle* aStyle) { |
31 | return new (aPresShell) |
32 | nsMathMLmmultiscriptsFrame(aStyle, aPresShell->GetPresContext()); |
33 | } |
34 | |
35 | NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmmultiscriptsFrame)void* nsMathMLmmultiscriptsFrame ::operator new(size_t sz, mozilla ::PresShell * aShell) { return aShell->AllocateFrame(nsQueryFrame ::nsMathMLmmultiscriptsFrame_id, sz); } |
36 | |
37 | nsMathMLmmultiscriptsFrame::~nsMathMLmmultiscriptsFrame() = default; |
38 | |
39 | uint8_t nsMathMLmmultiscriptsFrame::ScriptIncrement(nsIFrame* aFrame) { |
40 | if (!aFrame) return 0; |
41 | if (mFrames.ContainsFrame(aFrame)) { |
42 | if (mFrames.FirstChild() == aFrame || |
43 | aFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts_)) { |
44 | return 0; // No script increment for base frames or prescript markers |
45 | } |
46 | return 1; |
47 | } |
48 | return 0; // not a child |
49 | } |
50 | |
51 | NS_IMETHODIMPnsresult |
52 | nsMathMLmmultiscriptsFrame::TransmitAutomaticData() { |
53 | // if our base is an embellished operator, let its state bubble to us |
54 | mPresentationData.baseFrame = mFrames.FirstChild(); |
55 | GetEmbellishDataFrom(mPresentationData.baseFrame, mEmbellishData); |
56 | |
57 | // The TeXbook (Ch 17. p.141) says the superscript inherits the compression |
58 | // while the subscript is compressed. So here we collect subscripts and set |
59 | // the compression flag in them. |
60 | |
61 | int32_t count = 0; |
62 | bool isSubScript = !mContent->IsMathMLElement(nsGkAtoms::msup_); |
63 | |
64 | AutoTArray<nsIFrame*, 8> subScriptFrames; |
65 | nsIFrame* childFrame = mFrames.FirstChild(); |
66 | while (childFrame) { |
67 | if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts_)) { |
68 | // mprescripts frame |
69 | } else if (0 == count) { |
70 | // base frame |
71 | } else { |
72 | // super/subscript block |
73 | if (isSubScript) { |
74 | // subscript |
75 | subScriptFrames.AppendElement(childFrame); |
76 | } else { |
77 | // superscript |
78 | } |
79 | PropagateFrameFlagFor(childFrame, NS_FRAME_MATHML_SCRIPT_DESCENDANT); |
80 | isSubScript = !isSubScript; |
81 | } |
82 | count++; |
83 | childFrame = childFrame->GetNextSibling(); |
84 | } |
85 | for (int32_t i = subScriptFrames.Length() - 1; i >= 0; i--) { |
86 | childFrame = subScriptFrames[i]; |
87 | PropagatePresentationDataFor(childFrame, NS_MATHML_COMPRESSED0x00000002U, |
88 | NS_MATHML_COMPRESSED0x00000002U); |
89 | } |
90 | |
91 | return NS_OK; |
92 | } |
93 | |
94 | /* virtual */ |
95 | nsresult nsMathMLmmultiscriptsFrame::Place(DrawTarget* aDrawTarget, |
96 | const PlaceFlags& aFlags, |
97 | ReflowOutput& aDesiredSize) { |
98 | nscoord subScriptShift = 0; |
99 | nscoord supScriptShift = 0; |
100 | float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this); |
101 | |
102 | return PlaceMultiScript(PresContext(), aDrawTarget, aFlags, aDesiredSize, |
103 | this, subScriptShift, supScriptShift, |
104 | fontSizeInflation); |
105 | } |
106 | |
107 | // exported routine that both munderover and mmultiscripts share. |
108 | // munderover uses this when movablelimits is set. |
109 | nsresult nsMathMLmmultiscriptsFrame::PlaceMultiScript( |
110 | nsPresContext* aPresContext, DrawTarget* aDrawTarget, |
111 | const PlaceFlags& aFlags, ReflowOutput& aDesiredSize, |
112 | nsMathMLContainerFrame* aFrame, nscoord aUserSubScriptShift, |
113 | nscoord aUserSupScriptShift, float aFontSizeInflation) { |
114 | nsAtom* tag = aFrame->GetContent()->NodeInfo()->NameAtom(); |
115 | |
116 | // This function deals with both munderover etc. as well as msubsup etc. |
117 | // As the former behaves identically to the later, we treat it as such |
118 | // to avoid additional checks later. |
119 | if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::mover_)) |
120 | tag = nsGkAtoms::msup_; |
121 | else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munder_)) |
122 | tag = nsGkAtoms::msub_; |
123 | else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munderover_)) |
124 | tag = nsGkAtoms::msubsup_; |
125 | |
126 | nsBoundingMetrics bmFrame; |
127 | |
128 | nscoord minShiftFromXHeight, subDrop, supDrop; |
129 | |
130 | //////////////////////////////////////// |
131 | // Initialize super/sub shifts that |
132 | // depend only on the current font |
133 | //////////////////////////////////////// |
134 | |
135 | nsIFrame* baseFrame = aFrame->PrincipalChildList().FirstChild(); |
136 | |
137 | if (!baseFrame) { |
138 | if (tag == nsGkAtoms::mmultiscripts_) |
139 | aFrame->ReportErrorToConsole("NoBase"); |
140 | else |
141 | aFrame->ReportChildCountError(); |
142 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
143 | } |
144 | |
145 | // get x-height (an ex) |
146 | const nsStyleFont* font = aFrame->StyleFont(); |
147 | RefPtr<nsFontMetrics> fm = |
148 | nsLayoutUtils::GetFontMetricsForFrame(baseFrame, aFontSizeInflation); |
149 | |
150 | nscoord xHeight = fm->XHeight(); |
151 | |
152 | nscoord oneDevPixel = fm->AppUnitsPerDevPixel(); |
153 | RefPtr<gfxFont> mathFont = fm->GetThebesFontGroup()->GetFirstMathFont(); |
154 | // scriptspace from TeX for extra spacing after sup/subscript |
155 | nscoord scriptSpace; |
156 | if (mathFont) { |
157 | scriptSpace = mathFont->MathTable()->Constant( |
158 | gfxMathTable::SpaceAfterScript, oneDevPixel); |
159 | } else { |
160 | // (0.5pt in plain TeX) |
161 | scriptSpace = nsPresContext::CSSPointsToAppUnits(0.5f); |
162 | } |
163 | |
164 | // Try and read sub and sup drops from the MATH table. |
165 | if (mathFont) { |
166 | subDrop = mathFont->MathTable()->Constant( |
167 | gfxMathTable::SubscriptBaselineDropMin, oneDevPixel); |
168 | supDrop = mathFont->MathTable()->Constant( |
169 | gfxMathTable::SuperscriptBaselineDropMax, oneDevPixel); |
170 | } |
171 | |
172 | // force the scriptSpace to be at least 1 pixel |
173 | nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1); |
174 | scriptSpace = std::max(onePixel, scriptSpace); |
175 | |
176 | ///////////////////////////////////// |
177 | // first the shift for the subscript |
178 | |
179 | nscoord subScriptShift; |
180 | if (mathFont) { |
181 | // Try and get the sub script shift from the MATH table. Note that contrary |
182 | // to TeX we only have one parameter. |
183 | subScriptShift = mathFont->MathTable()->Constant( |
184 | gfxMathTable::SubscriptShiftDown, oneDevPixel); |
185 | } else { |
186 | // subScriptShift{1,2} |
187 | // = minimum amount to shift the subscript down |
188 | // = sub{1,2} in TeXbook |
189 | // subScriptShift1 = subscriptshift attribute * x-height |
190 | nscoord subScriptShift1, subScriptShift2; |
191 | // Get subScriptShift{1,2} default from font |
192 | GetSubScriptShifts(fm, subScriptShift1, subScriptShift2); |
193 | if (tag == nsGkAtoms::msub_) { |
194 | subScriptShift = subScriptShift1; |
195 | } else { |
196 | subScriptShift = std::max(subScriptShift1, subScriptShift2); |
197 | } |
198 | } |
199 | |
200 | if (0 < aUserSubScriptShift) { |
201 | // the user has set the subscriptshift attribute |
202 | subScriptShift = std::max(subScriptShift, aUserSubScriptShift); |
203 | } |
204 | |
205 | ///////////////////////////////////// |
206 | // next the shift for the superscript |
207 | |
208 | nscoord supScriptShift; |
209 | nsPresentationData presentationData; |
210 | aFrame->GetPresentationData(presentationData); |
211 | if (mathFont) { |
212 | // Try and get the super script shift from the MATH table. Note that |
213 | // contrary to TeX we only have two parameters. |
214 | supScriptShift = mathFont->MathTable()->Constant( |
215 | NS_MATHML_IS_COMPRESSED(presentationData.flags)(0x00000002U == ((presentationData.flags) & 0x00000002U)) |
216 | ? gfxMathTable::SuperscriptShiftUpCramped |
217 | : gfxMathTable::SuperscriptShiftUp, |
218 | oneDevPixel); |
219 | } else { |
220 | // supScriptShift{1,2,3} |
221 | // = minimum amount to shift the supscript up |
222 | // = sup{1,2,3} in TeX |
223 | // supScriptShift1 = superscriptshift attribute * x-height |
224 | // Note that there are THREE values for supscript shifts depending |
225 | // on the current style |
226 | nscoord supScriptShift1, supScriptShift2, supScriptShift3; |
227 | // Set supScriptShift{1,2,3} default from font |
228 | GetSupScriptShifts(fm, supScriptShift1, supScriptShift2, supScriptShift3); |
229 | |
230 | // get sup script shift depending on current script level and display style |
231 | // Rule 18c, App. G, TeXbook |
232 | if (font->mMathDepth == 0 && font->mMathStyle == StyleMathStyle::Normal && |
233 | !NS_MATHML_IS_COMPRESSED(presentationData.flags)(0x00000002U == ((presentationData.flags) & 0x00000002U))) { |
234 | // Style D in TeXbook |
235 | supScriptShift = supScriptShift1; |
236 | } else if (NS_MATHML_IS_COMPRESSED(presentationData.flags)(0x00000002U == ((presentationData.flags) & 0x00000002U))) { |
237 | // Style C' in TeXbook = D',T',S',SS' |
238 | supScriptShift = supScriptShift3; |
239 | } else { |
240 | // everything else = T,S,SS |
241 | supScriptShift = supScriptShift2; |
242 | } |
243 | } |
244 | |
245 | if (0 < aUserSupScriptShift) { |
246 | // the user has set the supscriptshift attribute |
247 | supScriptShift = std::max(supScriptShift, aUserSupScriptShift); |
248 | } |
249 | |
250 | //////////////////////////////////// |
251 | // Get the children's sizes |
252 | //////////////////////////////////// |
253 | |
254 | const WritingMode wm(aDesiredSize.GetWritingMode()); |
255 | nscoord width = 0, prescriptsWidth = 0, rightBearing = 0; |
256 | nscoord minSubScriptShift = 0, minSupScriptShift = 0; |
257 | nscoord trySubScriptShift = subScriptShift; |
258 | nscoord trySupScriptShift = supScriptShift; |
259 | nscoord maxSubScriptShift = subScriptShift; |
260 | nscoord maxSupScriptShift = supScriptShift; |
261 | ReflowOutput baseSize(wm); |
262 | ReflowOutput subScriptSize(wm); |
263 | ReflowOutput supScriptSize(wm); |
264 | ReflowOutput multiSubSize(wm), multiSupSize(wm); |
265 | baseFrame = nullptr; |
266 | nsIFrame* subScriptFrame = nullptr; |
267 | nsIFrame* supScriptFrame = nullptr; |
268 | nsIFrame* prescriptsFrame = nullptr; // frame of <mprescripts/>, if there. |
269 | |
270 | bool firstPrescriptsPair = false; |
271 | nsBoundingMetrics bmBase, bmSubScript, bmSupScript, bmMultiSub, bmMultiSup; |
272 | nsMargin baseMargin, subScriptMargin, supScriptMargin; |
273 | multiSubSize.SetBlockStartAscent(-0x7FFFFFFF); |
274 | multiSupSize.SetBlockStartAscent(-0x7FFFFFFF); |
275 | bmMultiSub.ascent = bmMultiSup.ascent = -0x7FFFFFFF; |
276 | bmMultiSub.descent = bmMultiSup.descent = -0x7FFFFFFF; |
277 | nscoord italicCorrection = 0; |
278 | |
279 | nsBoundingMetrics boundingMetrics; |
280 | boundingMetrics.width = 0; |
281 | boundingMetrics.ascent = boundingMetrics.descent = -0x7FFFFFFF; |
282 | aDesiredSize.Width() = aDesiredSize.Height() = 0; |
283 | |
284 | int32_t count = 0; |
285 | |
286 | // Boolean to determine whether the current child is a subscript. |
287 | // Note that only msup starts with a superscript. |
288 | bool isSubScript = (tag != nsGkAtoms::msup_); |
289 | |
290 | nsIFrame* childFrame = aFrame->PrincipalChildList().FirstChild(); |
291 | while (childFrame) { |
292 | if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts_)) { |
293 | if (tag != nsGkAtoms::mmultiscripts_) { |
294 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
295 | aFrame->ReportInvalidChildError(nsGkAtoms::mprescripts_); |
296 | } |
297 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
298 | } |
299 | if (prescriptsFrame) { |
300 | // duplicate <mprescripts/> found |
301 | // report an error, encourage people to get their markups in order |
302 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
303 | aFrame->ReportErrorToConsole("DuplicateMprescripts"); |
304 | } |
305 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
306 | } |
307 | if (!isSubScript) { |
308 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
309 | aFrame->ReportErrorToConsole("SubSupMismatch"); |
310 | } |
311 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
312 | } |
313 | |
314 | prescriptsFrame = childFrame; |
315 | firstPrescriptsPair = true; |
316 | } else if (0 == count) { |
317 | // base |
318 | baseFrame = childFrame; |
319 | GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase); |
320 | baseMargin = GetMarginForPlace(aFlags, baseFrame); |
321 | |
322 | if (tag != nsGkAtoms::msub_) { |
323 | // Apply italics correction if there is the potential for a |
324 | // postsupscript. |
325 | GetItalicCorrection(bmBase, italicCorrection); |
326 | // If italics correction is applied, we always add "a little to spare" |
327 | // (see TeXbook Ch.11, p.64), as we estimate the italic creation |
328 | // ourselves and it isn't the same as TeX. |
329 | italicCorrection += onePixel; |
330 | } |
331 | |
332 | // we update boundingMetrics.{ascent,descent} with that |
333 | // of the baseFrame only after processing all the sup/sub pairs |
334 | boundingMetrics.width = bmBase.width + baseMargin.LeftRight(); |
335 | boundingMetrics.rightBearing = |
336 | bmBase.rightBearing + baseMargin.LeftRight(); |
337 | boundingMetrics.leftBearing = bmBase.leftBearing; // until overwritten |
338 | } else { |
339 | // super/subscript block |
340 | if (isSubScript) { |
341 | // subscript |
342 | subScriptFrame = childFrame; |
343 | GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, |
344 | bmSubScript); |
345 | subScriptMargin = GetMarginForPlace(aFlags, subScriptFrame); |
346 | |
347 | if (!mathFont) { |
348 | // get the subdrop from the subscript font |
349 | GetSubDropFromChild(subScriptFrame, subDrop, aFontSizeInflation); |
350 | } |
351 | |
352 | // parameter v, Rule 18a, App. G, TeXbook |
353 | minSubScriptShift = bmBase.descent + baseMargin.bottom + subDrop; |
354 | trySubScriptShift = std::max(minSubScriptShift, subScriptShift); |
355 | multiSubSize.SetBlockStartAscent( |
356 | std::max(multiSubSize.BlockStartAscent(), |
357 | subScriptSize.BlockStartAscent() + subScriptMargin.top)); |
358 | bmMultiSub.ascent = std::max(bmMultiSub.ascent, |
359 | bmSubScript.ascent + subScriptMargin.top); |
360 | bmMultiSub.descent = std::max( |
361 | bmMultiSub.descent, bmSubScript.descent + subScriptMargin.bottom); |
362 | multiSubSize.Height() = |
363 | std::max(multiSubSize.Height(), |
364 | subScriptSize.Height() - subScriptSize.BlockStartAscent() + |
365 | subScriptMargin.bottom); |
366 | if (bmSubScript.width) { |
367 | width = bmSubScript.width + subScriptMargin.LeftRight() + scriptSpace; |
368 | } |
369 | rightBearing = bmSubScript.rightBearing + subScriptMargin.LeftRight(); |
370 | |
371 | if (tag == nsGkAtoms::msub_) { |
372 | boundingMetrics.rightBearing = boundingMetrics.width + rightBearing; |
373 | boundingMetrics.width += width; |
374 | |
375 | nscoord subscriptTopMax; |
376 | if (mathFont) { |
377 | subscriptTopMax = mathFont->MathTable()->Constant( |
378 | gfxMathTable::SubscriptTopMax, oneDevPixel); |
379 | } else { |
380 | // get min subscript shift limit from x-height |
381 | // = h(x) - 4/5 * sigma_5, Rule 18b, App. G, TeXbook |
382 | subscriptTopMax = NSToCoordRound((4.0f / 5.0f) * xHeight); |
383 | } |
384 | nscoord minShiftFromXHeight = |
385 | bmSubScript.ascent + subScriptMargin.top - subscriptTopMax; |
386 | maxSubScriptShift = std::max(trySubScriptShift, minShiftFromXHeight); |
387 | |
388 | maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift); |
389 | trySubScriptShift = subScriptShift; |
390 | } |
391 | } else { |
392 | // supscript |
393 | supScriptFrame = childFrame; |
394 | GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, |
395 | bmSupScript); |
396 | supScriptMargin = GetMarginForPlace(aFlags, supScriptFrame); |
397 | if (!mathFont) { |
398 | // get the supdrop from the supscript font |
399 | GetSupDropFromChild(supScriptFrame, supDrop, aFontSizeInflation); |
400 | } |
401 | // parameter u, Rule 18a, App. G, TeXbook |
402 | minSupScriptShift = bmBase.ascent + baseMargin.top - supDrop; |
403 | nscoord superscriptBottomMin; |
404 | if (mathFont) { |
405 | superscriptBottomMin = mathFont->MathTable()->Constant( |
406 | gfxMathTable::SuperscriptBottomMin, oneDevPixel); |
407 | } else { |
408 | // get min supscript shift limit from x-height |
409 | // = d(x) + 1/4 * sigma_5, Rule 18c, App. G, TeXbook |
410 | superscriptBottomMin = NSToCoordRound((1.0f / 4.0f) * xHeight); |
411 | } |
412 | minShiftFromXHeight = |
413 | bmSupScript.descent + supScriptMargin.bottom + superscriptBottomMin; |
414 | trySupScriptShift = std::max( |
415 | minSupScriptShift, std::max(minShiftFromXHeight, supScriptShift)); |
416 | multiSupSize.SetBlockStartAscent( |
417 | std::max(multiSupSize.BlockStartAscent(), |
418 | supScriptSize.BlockStartAscent() + supScriptMargin.top)); |
419 | bmMultiSup.ascent = std::max(bmMultiSup.ascent, |
420 | bmSupScript.ascent + supScriptMargin.top); |
421 | bmMultiSup.descent = std::max( |
422 | bmMultiSup.descent, bmSupScript.descent + supScriptMargin.bottom); |
423 | multiSupSize.Height() = |
424 | std::max(multiSupSize.Height(), |
425 | supScriptSize.Height() - supScriptSize.BlockStartAscent() + |
426 | supScriptMargin.bottom); |
427 | |
428 | if (bmSupScript.width) |
429 | width = |
430 | std::max(width, bmSupScript.width + supScriptMargin.LeftRight() + |
431 | scriptSpace); |
432 | |
433 | if (!prescriptsFrame) { // we are still looping over base & postscripts |
434 | rightBearing = std::max(rightBearing, |
435 | italicCorrection + bmSupScript.rightBearing + |
436 | supScriptMargin.LeftRight()); |
437 | boundingMetrics.rightBearing = boundingMetrics.width + rightBearing; |
438 | boundingMetrics.width += width; |
439 | } else { |
440 | prescriptsWidth += width; |
441 | if (firstPrescriptsPair) { |
442 | firstPrescriptsPair = false; |
443 | boundingMetrics.leftBearing = |
444 | std::min(bmSubScript.leftBearing, bmSupScript.leftBearing); |
445 | } |
446 | } |
447 | width = rightBearing = 0; |
448 | |
449 | // negotiate between the various shifts so that |
450 | // there is enough gap between the sup and subscripts |
451 | // Rule 18e, App. G, TeXbook |
452 | if (tag == nsGkAtoms::mmultiscripts_ || tag == nsGkAtoms::msubsup_) { |
453 | nscoord subSuperscriptGapMin; |
454 | if (mathFont) { |
455 | subSuperscriptGapMin = mathFont->MathTable()->Constant( |
456 | gfxMathTable::SubSuperscriptGapMin, oneDevPixel); |
457 | } else { |
458 | nscoord ruleSize; |
459 | GetRuleThickness(aDrawTarget, fm, ruleSize); |
460 | subSuperscriptGapMin = 4 * ruleSize; |
461 | } |
462 | nscoord gap = |
463 | (trySupScriptShift - bmSupScript.descent - |
464 | supScriptMargin.bottom) - |
465 | (subScriptMargin.top + bmSubScript.ascent - trySubScriptShift); |
466 | if (gap < subSuperscriptGapMin) { |
467 | // adjust trySubScriptShift to get a gap of subSuperscriptGapMin |
468 | trySubScriptShift += subSuperscriptGapMin - gap; |
469 | } |
470 | |
471 | // next we want to ensure that the bottom of the superscript |
472 | // will be > superscriptBottomMaxWithSubscript |
473 | nscoord superscriptBottomMaxWithSubscript; |
474 | if (mathFont) { |
475 | superscriptBottomMaxWithSubscript = mathFont->MathTable()->Constant( |
476 | gfxMathTable::SuperscriptBottomMaxWithSubscript, oneDevPixel); |
477 | } else { |
478 | superscriptBottomMaxWithSubscript = |
479 | NSToCoordRound((4.0f / 5.0f) * xHeight); |
480 | } |
481 | gap = superscriptBottomMaxWithSubscript - |
482 | (trySupScriptShift - bmSupScript.descent - |
483 | supScriptMargin.bottom); |
484 | if (gap > 0) { |
485 | trySupScriptShift += gap; |
486 | trySubScriptShift -= gap; |
487 | } |
488 | } |
489 | |
490 | maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift); |
491 | maxSupScriptShift = std::max(maxSupScriptShift, trySupScriptShift); |
492 | |
493 | trySubScriptShift = subScriptShift; |
494 | trySupScriptShift = supScriptShift; |
Value stored to 'trySupScriptShift' is never read | |
495 | } |
496 | |
497 | isSubScript = !isSubScript; |
498 | } |
499 | count++; |
500 | childFrame = childFrame->GetNextSibling(); |
501 | } |
502 | |
503 | // NoBase error may also have been reported above |
504 | if ((count != 2 && (tag == nsGkAtoms::msup_ || tag == nsGkAtoms::msub_)) || |
505 | (count != 3 && tag == nsGkAtoms::msubsup_) || !baseFrame || |
506 | (!isSubScript && tag == nsGkAtoms::mmultiscripts_)) { |
507 | // report an error, encourage people to get their markups in order |
508 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
509 | if ((count != 2 && |
510 | (tag == nsGkAtoms::msup_ || tag == nsGkAtoms::msub_)) || |
511 | (count != 3 && tag == nsGkAtoms::msubsup_)) { |
512 | aFrame->ReportChildCountError(); |
513 | } else if (!baseFrame) { |
514 | aFrame->ReportErrorToConsole("NoBase"); |
515 | } else { |
516 | aFrame->ReportErrorToConsole("SubSupMismatch"); |
517 | } |
518 | } |
519 | return aFrame->PlaceAsMrow(aDrawTarget, aFlags, aDesiredSize); |
520 | } |
521 | |
522 | // we left out the width of prescripts, so ... |
523 | boundingMetrics.rightBearing += prescriptsWidth; |
524 | boundingMetrics.width += prescriptsWidth; |
525 | |
526 | // Zero out the shifts in where a frame isn't present to avoid the potential |
527 | // for overflow. |
528 | if (!subScriptFrame) maxSubScriptShift = 0; |
529 | if (!supScriptFrame) maxSupScriptShift = 0; |
530 | |
531 | // we left out the base during our bounding box updates, so ... |
532 | if (tag == nsGkAtoms::msub_) { |
533 | boundingMetrics.ascent = std::max(bmBase.ascent + baseMargin.top, |
534 | bmMultiSub.ascent - maxSubScriptShift); |
535 | } else { |
536 | boundingMetrics.ascent = std::max(bmBase.ascent + baseMargin.top, |
537 | (bmMultiSup.ascent + maxSupScriptShift)); |
538 | } |
539 | if (tag == nsGkAtoms::msup_) { |
540 | boundingMetrics.descent = std::max(bmBase.descent + baseMargin.bottom, |
541 | bmMultiSup.descent - maxSupScriptShift); |
542 | } else { |
543 | boundingMetrics.descent = |
544 | std::max(bmBase.descent + baseMargin.bottom, |
545 | (bmMultiSub.descent + maxSubScriptShift)); |
546 | } |
547 | |
548 | // get the reflow metrics ... |
549 | aDesiredSize.SetBlockStartAscent( |
550 | std::max(baseSize.BlockStartAscent() + baseMargin.top, |
551 | std::max(multiSubSize.BlockStartAscent() - maxSubScriptShift, |
552 | multiSupSize.BlockStartAscent() + maxSupScriptShift))); |
553 | aDesiredSize.Height() = |
554 | aDesiredSize.BlockStartAscent() + |
555 | std::max( |
556 | baseSize.Height() - baseSize.BlockStartAscent() + baseMargin.bottom, |
557 | std::max(multiSubSize.Height() + maxSubScriptShift, |
558 | multiSupSize.Height() - maxSupScriptShift)); |
559 | aDesiredSize.Width() = boundingMetrics.width; |
560 | aDesiredSize.mBoundingMetrics = boundingMetrics; |
561 | |
562 | // Add padding+border. |
563 | auto borderPadding = aFrame->GetBorderPaddingForPlace(aFlags); |
564 | InflateReflowAndBoundingMetrics(borderPadding, aDesiredSize, boundingMetrics); |
565 | |
566 | aFrame->SetBoundingMetrics(boundingMetrics); |
567 | aFrame->SetReference(nsPoint(0, aDesiredSize.BlockStartAscent())); |
568 | |
569 | ////////////////// |
570 | // Place Children |
571 | |
572 | // Place prescripts, followed by base, and then postscripts. |
573 | // The list of frames is in the order: {base} {postscripts} {prescripts} |
574 | // We go over the list in a circular manner, starting at <prescripts/> |
575 | |
576 | if (!aFlags.contains(PlaceFlag::MeasureOnly)) { |
577 | const bool isRTL = |
578 | aFrame->StyleVisibility()->mDirection == StyleDirection::Rtl; |
579 | nscoord dx = isRTL ? borderPadding.right : borderPadding.left; |
580 | nscoord dy = 0; |
581 | |
582 | // With msub and msup there is only one element and |
583 | // subscriptFrame/supScriptFrame have already been set above where |
584 | // relevant. In these cases we skip to the reflow part. |
585 | if (tag == nsGkAtoms::msub_ || tag == nsGkAtoms::msup_) |
586 | count = 1; |
587 | else |
588 | count = 0; |
589 | childFrame = prescriptsFrame; |
590 | bool isPreScript = true; |
591 | do { |
592 | if (!childFrame) { // end of prescripts, |
593 | isPreScript = false; |
594 | // place the base ... |
595 | childFrame = baseFrame; |
596 | dy = aDesiredSize.BlockStartAscent() - baseSize.BlockStartAscent(); |
597 | baseMargin = GetMarginForPlace(aFlags, baseFrame); |
598 | dx += isRTL ? baseMargin.right : baseMargin.left; |
599 | FinishReflowChild( |
600 | baseFrame, aPresContext, baseSize, nullptr, |
601 | aFrame->MirrorIfRTL(aDesiredSize.Width(), baseSize.Width(), dx), dy, |
602 | ReflowChildFlags::Default); |
603 | dx += bmBase.width; |
604 | dx += isRTL ? baseMargin.left : baseMargin.right; |
605 | } else if (prescriptsFrame == childFrame) { |
606 | // Clear reflow flags of prescripts frame. |
607 | // FIXME (bug 1909417): We should call FinishReflowChild at the same |
608 | // position as baseFrame. |
609 | prescriptsFrame->DidReflow(aPresContext, nullptr); |
610 | } else { |
611 | // process each sup/sub pair |
612 | if (0 == count) { |
613 | subScriptFrame = childFrame; |
614 | count = 1; |
615 | } else if (1 == count) { |
616 | if (tag != nsGkAtoms::msub_) supScriptFrame = childFrame; |
617 | count = 0; |
618 | |
619 | // get the ascent/descent of sup/subscripts stored in their rects |
620 | // rect.x = descent, rect.y = ascent |
621 | if (subScriptFrame) { |
622 | GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, |
623 | bmSubScript); |
624 | subScriptMargin = GetMarginForPlace(aFlags, subScriptFrame); |
625 | } |
626 | if (supScriptFrame) { |
627 | GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, |
628 | bmSupScript); |
629 | supScriptMargin = GetMarginForPlace(aFlags, supScriptFrame); |
630 | } |
631 | |
632 | width = std::max(subScriptSize.Width() + subScriptMargin.LeftRight(), |
633 | supScriptSize.Width() + supScriptMargin.LeftRight()); |
634 | |
635 | if (subScriptFrame) { |
636 | nscoord x = |
637 | dx + (isRTL ? subScriptMargin.right : subScriptMargin.left); |
638 | // prescripts should be right aligned |
639 | // https://bugzilla.mozilla.org/show_bug.cgi?id=928675 |
640 | if (isPreScript) { |
641 | x += width - subScriptSize.Width() - subScriptMargin.LeftRight(); |
642 | } |
643 | dy = aDesiredSize.BlockStartAscent() - |
644 | subScriptSize.BlockStartAscent() + maxSubScriptShift; |
645 | FinishReflowChild(subScriptFrame, aPresContext, subScriptSize, |
646 | nullptr, |
647 | aFrame->MirrorIfRTL(aDesiredSize.Width(), |
648 | subScriptSize.Width(), x), |
649 | dy, ReflowChildFlags::Default); |
650 | } |
651 | |
652 | if (supScriptFrame) { |
653 | nscoord x = |
654 | dx + (isRTL ? supScriptMargin.right : supScriptMargin.left); |
655 | if (isPreScript) { |
656 | x += width - supScriptSize.Width() - supScriptMargin.LeftRight(); |
657 | } else { |
658 | // post superscripts are shifted by the italic correction value |
659 | x += italicCorrection; |
660 | } |
661 | dy = aDesiredSize.BlockStartAscent() - |
662 | supScriptSize.BlockStartAscent() - maxSupScriptShift; |
663 | FinishReflowChild(supScriptFrame, aPresContext, supScriptSize, |
664 | nullptr, |
665 | aFrame->MirrorIfRTL(aDesiredSize.Width(), |
666 | supScriptSize.Width(), x), |
667 | dy, ReflowChildFlags::Default); |
668 | } |
669 | dx += width + scriptSpace; |
670 | } |
671 | } |
672 | childFrame = childFrame->GetNextSibling(); |
673 | } while (prescriptsFrame != childFrame); |
674 | } |
675 | |
676 | return NS_OK; |
677 | } |