layout/mathml/nsMathMLmunderoverFrame.cpp@b8a032363ba2
layout/mathml/nsMathMLmunderoverFrame.cpp
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #include "nsMathMLmunderoverFrame.h"
7 #include "nsPresContext.h"
8 #include "nsRenderingContext.h"
9 #include "nsMathMLmmultiscriptsFrame.h"
10 #include <algorithm>
12 //
13 // <munderover> -- attach an underscript-overscript pair to a base - implementation
14 // <mover> -- attach an overscript to a base - implementation
15 // <munder> -- attach an underscript to a base - implementation
16 //
18 nsIFrame*
19 NS_NewMathMLmunderoverFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
20 {
21 return new (aPresShell) nsMathMLmunderoverFrame(aContext);
22 }
24 NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmunderoverFrame)
26 nsMathMLmunderoverFrame::~nsMathMLmunderoverFrame()
27 {
28 }
30 nsresult
31 nsMathMLmunderoverFrame::AttributeChanged(int32_t aNameSpaceID,
32 nsIAtom* aAttribute,
33 int32_t aModType)
34 {
35 if (nsGkAtoms::accent_ == aAttribute ||
36 nsGkAtoms::accentunder_ == aAttribute) {
37 // When we have automatic data to update within ourselves, we ask our
38 // parent to re-layout its children
39 return ReLayoutChildren(mParent);
40 }
42 return nsMathMLContainerFrame::
43 AttributeChanged(aNameSpaceID, aAttribute, aModType);
44 }
46 NS_IMETHODIMP
47 nsMathMLmunderoverFrame::UpdatePresentationData(uint32_t aFlagsValues,
48 uint32_t aFlagsToUpdate)
49 {
50 nsMathMLContainerFrame::UpdatePresentationData(aFlagsValues, aFlagsToUpdate);
51 // disable the stretch-all flag if we are going to act like a subscript-superscript pair
52 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) &&
53 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) {
54 mPresentationData.flags &= ~NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY;
55 }
56 else {
57 mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY;
58 }
59 return NS_OK;
60 }
62 NS_IMETHODIMP
63 nsMathMLmunderoverFrame::InheritAutomaticData(nsIFrame* aParent)
64 {
65 // let the base class get the default from our parent
66 nsMathMLContainerFrame::InheritAutomaticData(aParent);
68 mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY;
70 return NS_OK;
71 }
73 uint8_t
74 nsMathMLmunderoverFrame::ScriptIncrement(nsIFrame* aFrame)
75 {
76 nsIFrame* child = mFrames.FirstChild();
77 if (!aFrame || aFrame == child) {
78 return 0;
79 }
80 child = child->GetNextSibling();
81 if (aFrame == child) {
82 if (mContent->Tag() == nsGkAtoms::mover_) {
83 return mIncrementOver ? 1 : 0;
84 }
85 return mIncrementUnder ? 1 : 0;
86 }
87 if (child && aFrame == child->GetNextSibling()) {
88 // must be a over frame of munderover
89 return mIncrementOver ? 1 : 0;
90 }
91 return 0; // frame not found
92 }
94 NS_IMETHODIMP
95 nsMathMLmunderoverFrame::TransmitAutomaticData()
96 {
97 // At this stage, all our children are in sync and we can fully
98 // resolve our own mEmbellishData struct
99 //---------------------------------------------------------------------
101 /*
102 The REC says:
104 As regards munder (respectively mover) :
105 The default value of accentunder is false, unless underscript
106 is an <mo> element or an embellished operator. If underscript is
107 an <mo> element, the value of its accent attribute is used as the
108 default value of accentunder. If underscript is an embellished
109 operator, the accent attribute of the <mo> element at its
110 core is used as the default value. As with all attributes, an
111 explicitly given value overrides the default.
113 XXX The winner is the outermost setting in conflicting settings like these:
114 <munder accentunder='true'>
115 <mi>...</mi>
116 <mo accentunder='false'> ... </mo>
117 </munder>
119 As regards munderover:
120 The accent and accentunder attributes have the same effect as
121 the attributes with the same names on <mover> and <munder>,
122 respectively. Their default values are also computed in the
123 same manner as described for those elements, with the default
124 value of accent depending on overscript and the default value
125 of accentunder depending on underscript.
126 */
128 nsIFrame* overscriptFrame = nullptr;
129 nsIFrame* underscriptFrame = nullptr;
130 nsIFrame* baseFrame = mFrames.FirstChild();
131 nsIAtom* tag = mContent->Tag();
133 if (baseFrame) {
134 if (tag == nsGkAtoms::munder_ ||
135 tag == nsGkAtoms::munderover_) {
136 underscriptFrame = baseFrame->GetNextSibling();
137 } else {
138 NS_ASSERTION(tag == nsGkAtoms::mover_, "mContent->Tag() not recognized");
139 overscriptFrame = baseFrame->GetNextSibling();
140 }
141 }
142 if (underscriptFrame &&
143 tag == nsGkAtoms::munderover_) {
144 overscriptFrame = underscriptFrame->GetNextSibling();
146 }
148 // if our base is an embellished operator, let its state bubble to us (in particular,
149 // this is where we get the flag for NS_MATHML_EMBELLISH_MOVABLELIMITS). Our flags
150 // are reset to the default values of false if the base frame isn't embellished.
151 mPresentationData.baseFrame = baseFrame;
152 GetEmbellishDataFrom(baseFrame, mEmbellishData);
154 // The default value of accentunder is false, unless the underscript is embellished
155 // and its core <mo> is an accent
156 nsEmbellishData embellishData;
157 nsAutoString value;
158 if (tag == nsGkAtoms::munder_ ||
159 tag == nsGkAtoms::munderover_) {
160 GetEmbellishDataFrom(underscriptFrame, embellishData);
161 if (NS_MATHML_EMBELLISH_IS_ACCENT(embellishData.flags)) {
162 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTUNDER;
163 } else {
164 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTUNDER;
165 }
167 // if we have an accentunder attribute, it overrides what the underscript said
168 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accentunder_, value)) {
169 if (value.EqualsLiteral("true")) {
170 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTUNDER;
171 } else if (value.EqualsLiteral("false")) {
172 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTUNDER;
173 }
174 }
175 }
177 // The default value of accent is false, unless the overscript is embellished
178 // and its core <mo> is an accent
179 if (tag == nsGkAtoms::mover_ ||
180 tag == nsGkAtoms::munderover_) {
181 GetEmbellishDataFrom(overscriptFrame, embellishData);
182 if (NS_MATHML_EMBELLISH_IS_ACCENT(embellishData.flags)) {
183 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTOVER;
184 } else {
185 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTOVER;
186 }
188 // if we have an accent attribute, it overrides what the overscript said
189 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accent_, value)) {
190 if (value.EqualsLiteral("true")) {
191 mEmbellishData.flags |= NS_MATHML_EMBELLISH_ACCENTOVER;
192 } else if (value.EqualsLiteral("false")) {
193 mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_ACCENTOVER;
194 }
195 }
196 }
198 bool subsupDisplay =
199 NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) &&
200 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE;
202 // disable the stretch-all flag if we are going to act like a superscript
203 if (subsupDisplay) {
204 mPresentationData.flags &= ~NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY;
205 }
207 // Now transmit any change that we want to our children so that they
208 // can update their mPresentationData structs
209 //---------------------------------------------------------------------
211 /* The REC says:
212 Within underscript, <munderover> always sets displaystyle to "false",
213 but increments scriptlevel by 1 only when accentunder is "false".
215 Within overscript, <munderover> always sets displaystyle to "false",
216 but increments scriptlevel by 1 only when accent is "false".
218 Within subscript and superscript it increments scriptlevel by 1, and
219 sets displaystyle to "false", but leaves both attributes unchanged within
220 base.
222 The TeXBook treats 'over' like a superscript, so p.141 or Rule 13a
223 say it shouldn't be compressed. However, The TeXBook says
224 that math accents and \overline change uncramped styles to their
225 cramped counterparts.
226 */
227 if (tag == nsGkAtoms::mover_ ||
228 tag == nsGkAtoms::munderover_) {
229 uint32_t compress = NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)
230 ? NS_MATHML_COMPRESSED : 0;
231 mIncrementOver =
232 !NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags) ||
233 subsupDisplay;
234 SetIncrementScriptLevel(tag == nsGkAtoms::mover_ ? 1 : 2, mIncrementOver);
235 if (mIncrementOver) {
236 PropagateFrameFlagFor(overscriptFrame,
237 NS_FRAME_MATHML_SCRIPT_DESCENDANT);
238 }
239 PropagatePresentationDataFor(overscriptFrame, compress, compress);
240 }
241 /*
242 The TeXBook treats 'under' like a subscript, so p.141 or Rule 13a
243 say it should be compressed
244 */
245 if (tag == nsGkAtoms::munder_ ||
246 tag == nsGkAtoms::munderover_) {
247 mIncrementUnder =
248 !NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags) ||
249 subsupDisplay;
250 SetIncrementScriptLevel(1, mIncrementUnder);
251 if (mIncrementUnder) {
252 PropagateFrameFlagFor(underscriptFrame,
253 NS_FRAME_MATHML_SCRIPT_DESCENDANT);
254 }
255 PropagatePresentationDataFor(underscriptFrame,
256 NS_MATHML_COMPRESSED,
257 NS_MATHML_COMPRESSED);
258 }
259 return NS_OK;
260 }
262 /*
263 The REC says:
264 * If the base is an operator with movablelimits="true" (or an embellished
265 operator whose <mo> element core has movablelimits="true"), and
266 displaystyle="false", then underscript and overscript are drawn in
267 a subscript and superscript position, respectively. In this case,
268 the accent and accentunder attributes are ignored. This is often
269 used for limits on symbols such as ∑.
271 i.e.,:
272 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishDataflags) &&
273 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) {
274 // place like subscript-superscript pair
275 }
276 else {
277 // place like underscript-overscript pair
278 }
279 */
281 /* virtual */ nsresult
282 nsMathMLmunderoverFrame::Place(nsRenderingContext& aRenderingContext,
283 bool aPlaceOrigin,
284 nsHTMLReflowMetrics& aDesiredSize)
285 {
286 nsIAtom* tag = mContent->Tag();
287 if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) &&
288 StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) {
289 //place like sub sup or subsup
290 nscoord scriptSpace = nsPresContext::CSSPointsToAppUnits(0.5f);
291 if (tag == nsGkAtoms::munderover_) {
292 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
293 aRenderingContext,
294 aPlaceOrigin,
295 aDesiredSize,
296 this, 0, 0,
297 scriptSpace);
298 } else if (tag == nsGkAtoms::munder_) {
299 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
300 aRenderingContext,
301 aPlaceOrigin,
302 aDesiredSize,
303 this, 0, 0,
304 scriptSpace);
305 } else {
306 NS_ASSERTION(tag == nsGkAtoms::mover_, "mContent->Tag() not recognized");
307 return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
308 aRenderingContext,
309 aPlaceOrigin,
310 aDesiredSize,
311 this, 0, 0,
312 scriptSpace);
313 }
315 }
317 ////////////////////////////////////
318 // Get the children's desired sizes
320 nsBoundingMetrics bmBase, bmUnder, bmOver;
321 nsHTMLReflowMetrics baseSize(aDesiredSize.GetWritingMode());
322 nsHTMLReflowMetrics underSize(aDesiredSize.GetWritingMode());
323 nsHTMLReflowMetrics overSize(aDesiredSize.GetWritingMode());
324 nsIFrame* overFrame = nullptr;
325 nsIFrame* underFrame = nullptr;
326 nsIFrame* baseFrame = mFrames.FirstChild();
327 underSize.SetTopAscent(0);
328 overSize.SetTopAscent(0);
329 bool haveError = false;
330 if (baseFrame) {
331 if (tag == nsGkAtoms::munder_ ||
332 tag == nsGkAtoms::munderover_) {
333 underFrame = baseFrame->GetNextSibling();
334 } else if (tag == nsGkAtoms::mover_) {
335 overFrame = baseFrame->GetNextSibling();
336 }
337 }
338 if (underFrame && tag == nsGkAtoms::munderover_) {
339 overFrame = underFrame->GetNextSibling();
340 }
342 if (tag == nsGkAtoms::munder_) {
343 if (!baseFrame || !underFrame || underFrame->GetNextSibling()) {
344 // report an error, encourage people to get their markups in order
345 haveError = true;
346 }
347 }
348 if (tag == nsGkAtoms::mover_) {
349 if (!baseFrame || !overFrame || overFrame->GetNextSibling()) {
350 // report an error, encourage people to get their markups in order
351 haveError = true;
352 }
353 }
354 if (tag == nsGkAtoms::munderover_) {
355 if (!baseFrame || !underFrame || !overFrame || overFrame->GetNextSibling()) {
356 // report an error, encourage people to get their markups in order
357 haveError = true;
358 }
359 }
360 if (haveError) {
361 if (aPlaceOrigin) {
362 ReportChildCountError();
363 }
364 return ReflowError(aRenderingContext, aDesiredSize);
365 }
366 GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase);
367 if (underFrame) {
368 GetReflowAndBoundingMetricsFor(underFrame, underSize, bmUnder);
369 }
370 if (overFrame) {
371 GetReflowAndBoundingMetricsFor(overFrame, overSize, bmOver);
372 }
374 nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
376 ////////////////////
377 // Place Children
379 nsRefPtr<nsFontMetrics> fm;
380 nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm));
381 aRenderingContext.SetFont(fm);
383 nscoord xHeight = fm->XHeight();
385 nscoord ruleThickness;
386 GetRuleThickness (aRenderingContext, fm, ruleThickness);
388 nscoord correction = 0;
389 GetItalicCorrection (bmBase, correction);
391 // there are 2 different types of placement depending on
392 // whether we want an accented under or not
394 nscoord underDelta1 = 0; // gap between base and underscript
395 nscoord underDelta2 = 0; // extra space beneath underscript
397 if (!NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) {
398 // Rule 13a, App. G, TeXbook
399 nscoord bigOpSpacing2, bigOpSpacing4, bigOpSpacing5, dummy;
400 GetBigOpSpacings (fm,
401 dummy, bigOpSpacing2,
402 dummy, bigOpSpacing4,
403 bigOpSpacing5);
404 underDelta1 = std::max(bigOpSpacing2, (bigOpSpacing4 - bmUnder.ascent));
405 underDelta2 = bigOpSpacing5;
406 }
407 else {
408 // No corresponding rule in TeXbook - we are on our own here
409 // XXX tune the gap delta between base and underscript
411 // Should we use Rule 10 like \underline does?
412 underDelta1 = ruleThickness + onePixel/2;
413 underDelta2 = ruleThickness;
414 }
415 // empty under?
416 if (!(bmUnder.ascent + bmUnder.descent)) {
417 underDelta1 = 0;
418 underDelta2 = 0;
419 }
421 nscoord overDelta1 = 0; // gap between base and overscript
422 nscoord overDelta2 = 0; // extra space above overscript
424 if (!NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) {
425 // Rule 13a, App. G, TeXbook
426 nscoord bigOpSpacing1, bigOpSpacing3, bigOpSpacing5, dummy;
427 GetBigOpSpacings (fm,
428 bigOpSpacing1, dummy,
429 bigOpSpacing3, dummy,
430 bigOpSpacing5);
431 overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - bmOver.descent));
432 overDelta2 = bigOpSpacing5;
434 // XXX This is not a TeX rule...
435 // delta1 (as computed abvove) can become really big when bmOver.descent is
436 // negative, e.g., if the content is &OverBar. In such case, we use the height
437 if (bmOver.descent < 0)
438 overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - (bmOver.ascent + bmOver.descent)));
439 }
440 else {
441 // Rule 12, App. G, TeXbook
442 // We are going to modify this rule to make it more general.
443 // The idea behind Rule 12 in the TeXBook is to keep the accent
444 // as close to the base as possible, while ensuring that the
445 // distance between the *baseline* of the accent char and
446 // the *baseline* of the base is atleast x-height.
447 // The idea is that for normal use, we would like all the accents
448 // on a line to line up atleast x-height above the baseline
449 // if possible.
450 // When the ascent of the base is >= x-height,
451 // the baseline of the accent char is placed just above the base
452 // (specifically, the baseline of the accent char is placed
453 // above the baseline of the base by the ascent of the base).
454 // For ease of implementation,
455 // this assumes that the font-designer designs accents
456 // in such a way that the bottom of the accent is atleast x-height
457 // above its baseline, otherwise there will be collisions
458 // with the base. Also there should be proper padding between
459 // the bottom of the accent char and its baseline.
460 // The above rule may not be obvious from a first
461 // reading of rule 12 in the TeXBook !!!
462 // The mathml <mover> tag can use accent chars that
463 // do not follow this convention. So we modify TeX's rule
464 // so that TeX's rule gets subsumed for accents that follow
465 // TeX's convention,
466 // while also allowing accents that do not follow the convention :
467 // we try to keep the *bottom* of the accent char atleast x-height
468 // from the baseline of the base char. we also slap on an extra
469 // padding between the accent and base chars.
470 overDelta1 = ruleThickness + onePixel/2;
471 if (bmBase.ascent < xHeight) {
472 // also ensure at least x-height above the baseline of the base
473 overDelta1 += xHeight - bmBase.ascent;
474 }
475 overDelta2 = ruleThickness;
476 }
477 // empty over?
478 if (!(bmOver.ascent + bmOver.descent)) {
479 overDelta1 = 0;
480 overDelta2 = 0;
481 }
483 nscoord dxBase = 0, dxOver = 0, dxUnder = 0;
484 nsAutoString valueAlign;
485 enum {
486 center,
487 left,
488 right
489 } alignPosition = center;
491 if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::align, valueAlign)) {
492 if (valueAlign.EqualsLiteral("left")) {
493 alignPosition = left;
494 } else if (valueAlign.EqualsLiteral("right")) {
495 alignPosition = right;
496 }
497 }
499 //////////
500 // pass 1, do what <mover> does: attach the overscript on the base
502 // Ad-hoc - This is to override fonts which have ready-made _accent_
503 // glyphs with negative lbearing and rbearing. We want to position
504 // the overscript ourselves
505 nscoord overWidth = bmOver.width;
506 if (!overWidth && (bmOver.rightBearing - bmOver.leftBearing > 0)) {
507 overWidth = bmOver.rightBearing - bmOver.leftBearing;
508 dxOver = -bmOver.leftBearing;
509 }
511 if (NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) {
512 mBoundingMetrics.width = bmBase.width;
513 if (alignPosition == center) {
514 dxOver += correction;
515 }
516 }
517 else {
518 mBoundingMetrics.width = std::max(bmBase.width, overWidth);
519 if (alignPosition == center) {
520 dxOver += correction/2;
521 }
522 }
524 if (alignPosition == center) {
525 dxOver += (mBoundingMetrics.width - overWidth)/2;
526 dxBase = (mBoundingMetrics.width - bmBase.width)/2;
527 } else if (alignPosition == right) {
528 dxOver += mBoundingMetrics.width - overWidth;
529 dxBase = mBoundingMetrics.width - bmBase.width;
530 }
532 mBoundingMetrics.ascent =
533 bmBase.ascent + overDelta1 + bmOver.ascent + bmOver.descent;
534 mBoundingMetrics.descent = bmBase.descent;
535 mBoundingMetrics.leftBearing =
536 std::min(dxBase + bmBase.leftBearing, dxOver + bmOver.leftBearing);
537 mBoundingMetrics.rightBearing =
538 std::max(dxBase + bmBase.rightBearing, dxOver + bmOver.rightBearing);
540 //////////
541 // pass 2, do what <munder> does: attach the underscript on the previous
542 // result. We conceptually view the previous result as an "anynomous base"
543 // from where to attach the underscript. Hence if the underscript is empty,
544 // we should end up like <mover>. If the overscript is empty, we should
545 // end up like <munder>.
547 nsBoundingMetrics bmAnonymousBase = mBoundingMetrics;
548 nscoord ascentAnonymousBase =
549 std::max(mBoundingMetrics.ascent + overDelta2,
550 overSize.TopAscent() + bmOver.descent + overDelta1 + bmBase.ascent);
551 ascentAnonymousBase = std::max(ascentAnonymousBase, baseSize.TopAscent());
553 // Width of non-spacing marks is zero so use left and right bearing.
554 nscoord underWidth = bmUnder.width;
555 if (!underWidth) {
556 underWidth = bmUnder.rightBearing - bmUnder.leftBearing;
557 dxUnder = -bmUnder.leftBearing;
558 }
560 nscoord maxWidth = std::max(bmAnonymousBase.width, underWidth);
561 if (alignPosition == center &&
562 !NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) {
563 GetItalicCorrection(bmAnonymousBase, correction);
564 dxUnder += -correction/2;
565 }
566 nscoord dxAnonymousBase = 0;
567 if (alignPosition == center) {
568 dxUnder += (maxWidth - underWidth)/2;
569 dxAnonymousBase = (maxWidth - bmAnonymousBase.width)/2;
570 } else if (alignPosition == right) {
571 dxUnder += maxWidth - underWidth;
572 dxAnonymousBase = maxWidth - bmAnonymousBase.width;
573 }
575 // adjust the offsets of the real base and overscript since their
576 // final offsets should be relative to us...
577 dxOver += dxAnonymousBase;
578 dxBase += dxAnonymousBase;
580 mBoundingMetrics.width =
581 std::max(dxAnonymousBase + bmAnonymousBase.width, dxUnder + bmUnder.width);
582 // At this point, mBoundingMetrics.ascent = bmAnonymousBase.ascent
583 mBoundingMetrics.descent =
584 bmAnonymousBase.descent + underDelta1 + bmUnder.ascent + bmUnder.descent;
585 mBoundingMetrics.leftBearing =
586 std::min(dxAnonymousBase + bmAnonymousBase.leftBearing, dxUnder + bmUnder.leftBearing);
587 mBoundingMetrics.rightBearing =
588 std::max(dxAnonymousBase + bmAnonymousBase.rightBearing, dxUnder + bmUnder.rightBearing);
590 aDesiredSize.SetTopAscent(ascentAnonymousBase);
591 aDesiredSize.Height() = aDesiredSize.TopAscent() +
592 std::max(mBoundingMetrics.descent + underDelta2,
593 bmAnonymousBase.descent + underDelta1 + bmUnder.ascent +
594 underSize.Height() - underSize.TopAscent());
595 aDesiredSize.Height() = std::max(aDesiredSize.Height(),
596 aDesiredSize.TopAscent() +
597 baseSize.Height() - baseSize.TopAscent());
598 aDesiredSize.Width() = mBoundingMetrics.width;
599 aDesiredSize.mBoundingMetrics = mBoundingMetrics;
601 mReference.x = 0;
602 mReference.y = aDesiredSize.TopAscent();
604 if (aPlaceOrigin) {
605 nscoord dy;
606 // place overscript
607 if (overFrame) {
608 dy = aDesiredSize.TopAscent() - mBoundingMetrics.ascent + bmOver.ascent
609 - overSize.TopAscent();
610 FinishReflowChild (overFrame, PresContext(), overSize, nullptr, dxOver, dy, 0);
611 }
612 // place base
613 dy = aDesiredSize.TopAscent() - baseSize.TopAscent();
614 FinishReflowChild (baseFrame, PresContext(), baseSize, nullptr, dxBase, dy, 0);
615 // place underscript
616 if (underFrame) {
617 dy = aDesiredSize.TopAscent() + mBoundingMetrics.descent - bmUnder.descent
618 - underSize.TopAscent();
619 FinishReflowChild (underFrame, PresContext(), underSize, nullptr,
620 dxUnder, dy, 0);
621 }
622 }
623 return NS_OK;
624 }
