bool
nsView::WindowResized(nsIWidget* aWidget, int32_t aWidth, int32_t aHeight)
{
// The root view may not be set if this is the resize associated with
// window creation
SetForcedRepaint(true);
if (this == mViewManager->GetRootView()) {
RefPtr<nsDeviceContext> devContext = mViewManager->GetDeviceContext();
// ensure DPI is up-to-date, in case of window being opened and sized
// on a non-default-dpi display (bug 829963)
devContext->CheckDPIChange();
int32_t p2a = devContext->AppUnitsPerDevPixel();
mViewManager->SetWindowDimensions(NSIntPixelsToAppUnits(aWidth, p2a),
NSIntPixelsToAppUnits(aHeight, p2a));
nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
if (pm) {
nsIPresShell* presShell = mViewManager->GetPresShell();
if (presShell && presShell->GetDocument()) {
pm->AdjustPopupsOnWindowChange(presShell);
}
}
return true;
}
else if (IsPopupWidget(aWidget)) {
nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
if (pm) {
pm->PopupResized(mFrame, LayoutDeviceIntSize(aWidth, aHeight));
return true;
}
}
return false;
}
/* virtual */ nsresult
nsMathMLmunderoverFrame::Place(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize)
{
float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
if (NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(mEmbellishData.flags) &&
StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_INLINE) {
//place like sub sup or subsup
if (mContent->IsMathMLElement(nsGkAtoms::munderover_)) {
return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
aDrawTarget,
aPlaceOrigin,
aDesiredSize,
this, 0, 0,
fontSizeInflation);
} else if (mContent->IsMathMLElement( nsGkAtoms::munder_)) {
return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
aDrawTarget,
aPlaceOrigin,
aDesiredSize,
this, 0, 0,
fontSizeInflation);
} else {
NS_ASSERTION(mContent->IsMathMLElement(nsGkAtoms::mover_),
"mContent->NodeInfo()->NameAtom() not recognized");
return nsMathMLmmultiscriptsFrame::PlaceMultiScript(PresContext(),
aDrawTarget,
aPlaceOrigin,
aDesiredSize,
this, 0, 0,
fontSizeInflation);
}
}
////////////////////////////////////
// Get the children's desired sizes
nsBoundingMetrics bmBase, bmUnder, bmOver;
ReflowOutput baseSize(aDesiredSize.GetWritingMode());
ReflowOutput underSize(aDesiredSize.GetWritingMode());
ReflowOutput overSize(aDesiredSize.GetWritingMode());
nsIFrame* overFrame = nullptr;
nsIFrame* underFrame = nullptr;
nsIFrame* baseFrame = mFrames.FirstChild();
underSize.SetBlockStartAscent(0);
overSize.SetBlockStartAscent(0);
bool haveError = false;
if (baseFrame) {
if (mContent->IsAnyOfMathMLElements(nsGkAtoms::munder_,
nsGkAtoms::munderover_)) {
underFrame = baseFrame->GetNextSibling();
} else if (mContent->IsMathMLElement(nsGkAtoms::mover_)) {
overFrame = baseFrame->GetNextSibling();
}
}
if (underFrame && mContent->IsMathMLElement(nsGkAtoms::munderover_)) {
overFrame = underFrame->GetNextSibling();
}
if (mContent->IsMathMLElement(nsGkAtoms::munder_)) {
if (!baseFrame || !underFrame || underFrame->GetNextSibling()) {
// report an error, encourage people to get their markups in order
haveError = true;
}
}
if (mContent->IsMathMLElement(nsGkAtoms::mover_)) {
if (!baseFrame || !overFrame || overFrame->GetNextSibling()) {
// report an error, encourage people to get their markups in order
haveError = true;
}
}
if (mContent->IsMathMLElement(nsGkAtoms::munderover_)) {
if (!baseFrame || !underFrame || !overFrame || overFrame->GetNextSibling()) {
// report an error, encourage people to get their markups in order
haveError = true;
}
}
if (haveError) {
if (aPlaceOrigin) {
ReportChildCountError();
}
return ReflowError(aDrawTarget, aDesiredSize);
}
GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase);
if (underFrame) {
GetReflowAndBoundingMetricsFor(underFrame, underSize, bmUnder);
}
if (overFrame) {
GetReflowAndBoundingMetricsFor(overFrame, overSize, bmOver);
}
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
////////////////////
// Place Children
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetFontMetricsForFrame(this, fontSizeInflation);
nscoord xHeight = fm->XHeight();
nscoord oneDevPixel = fm->AppUnitsPerDevPixel();
gfxFont* mathFont = fm->GetThebesFontGroup()->GetFirstMathFont();
nscoord ruleThickness;
GetRuleThickness (aDrawTarget, fm, ruleThickness);
nscoord correction = 0;
GetItalicCorrection (bmBase, correction);
// there are 2 different types of placement depending on
// whether we want an accented under or not
nscoord underDelta1 = 0; // gap between base and underscript
nscoord underDelta2 = 0; // extra space beneath underscript
if (!NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) {
// Rule 13a, App. G, TeXbook
nscoord bigOpSpacing2, bigOpSpacing4, bigOpSpacing5, dummy;
GetBigOpSpacings (fm,
dummy, bigOpSpacing2,
dummy, bigOpSpacing4,
bigOpSpacing5);
if (mathFont) {
// XXXfredw The Open Type MATH table has some StretchStack* parameters
// that we may use when the base is a stretchy horizontal operator. See
// bug 963131.
bigOpSpacing2 =
mathFont->GetMathConstant(gfxFontEntry::LowerLimitGapMin,
oneDevPixel);
bigOpSpacing4 =
mathFont->GetMathConstant(gfxFontEntry::LowerLimitBaselineDropMin,
oneDevPixel);
bigOpSpacing5 = 0;
}
underDelta1 = std::max(bigOpSpacing2, (bigOpSpacing4 - bmUnder.ascent));
underDelta2 = bigOpSpacing5;
}
else {
// No corresponding rule in TeXbook - we are on our own here
// XXX tune the gap delta between base and underscript
// XXX Should we use Rule 10 like \underline does?
// XXXfredw Perhaps use the Underbar* parameters of the MATH table. See
// bug 963125.
underDelta1 = ruleThickness + onePixel/2;
underDelta2 = ruleThickness;
}
// empty under?
if (!(bmUnder.ascent + bmUnder.descent)) {
underDelta1 = 0;
underDelta2 = 0;
}
nscoord overDelta1 = 0; // gap between base and overscript
nscoord overDelta2 = 0; // extra space above overscript
if (!NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) {
// Rule 13a, App. G, TeXbook
// XXXfredw The Open Type MATH table has some StretchStack* parameters
// that we may use when the base is a stretchy horizontal operator. See
// bug 963131.
nscoord bigOpSpacing1, bigOpSpacing3, bigOpSpacing5, dummy;
GetBigOpSpacings (fm,
bigOpSpacing1, dummy,
bigOpSpacing3, dummy,
bigOpSpacing5);
if (mathFont) {
// XXXfredw The Open Type MATH table has some StretchStack* parameters
// that we may use when the base is a stretchy horizontal operator. See
// bug 963131.
bigOpSpacing1 =
mathFont->GetMathConstant(gfxFontEntry::UpperLimitGapMin,
oneDevPixel);
bigOpSpacing3 =
mathFont->GetMathConstant(gfxFontEntry::UpperLimitBaselineRiseMin,
oneDevPixel);
bigOpSpacing5 = 0;
}
overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - bmOver.descent));
overDelta2 = bigOpSpacing5;
// XXX This is not a TeX rule...
// delta1 (as computed abvove) can become really big when bmOver.descent is
// negative, e.g., if the content is &OverBar. In such case, we use the height
if (bmOver.descent < 0)
overDelta1 = std::max(bigOpSpacing1, (bigOpSpacing3 - (bmOver.ascent + bmOver.descent)));
}
else {
// Rule 12, App. G, TeXbook
// We are going to modify this rule to make it more general.
// The idea behind Rule 12 in the TeXBook is to keep the accent
// as close to the base as possible, while ensuring that the
// distance between the *baseline* of the accent char and
// the *baseline* of the base is atleast x-height.
// The idea is that for normal use, we would like all the accents
// on a line to line up atleast x-height above the baseline
// if possible.
// When the ascent of the base is >= x-height,
// the baseline of the accent char is placed just above the base
// (specifically, the baseline of the accent char is placed
// above the baseline of the base by the ascent of the base).
// For ease of implementation,
// this assumes that the font-designer designs accents
// in such a way that the bottom of the accent is atleast x-height
// above its baseline, otherwise there will be collisions
// with the base. Also there should be proper padding between
// the bottom of the accent char and its baseline.
// The above rule may not be obvious from a first
// reading of rule 12 in the TeXBook !!!
// The mathml <mover> tag can use accent chars that
// do not follow this convention. So we modify TeX's rule
// so that TeX's rule gets subsumed for accents that follow
// TeX's convention,
// while also allowing accents that do not follow the convention :
// we try to keep the *bottom* of the accent char atleast x-height
// from the baseline of the base char. we also slap on an extra
// padding between the accent and base chars.
overDelta1 = ruleThickness + onePixel/2;
nscoord accentBaseHeight = xHeight;
if (mathFont) {
accentBaseHeight =
mathFont->GetMathConstant(gfxFontEntry::AccentBaseHeight,
oneDevPixel);
}
if (bmBase.ascent < accentBaseHeight) {
// also ensure at least accentBaseHeight above the baseline of the base
overDelta1 += accentBaseHeight - bmBase.ascent;
}
overDelta2 = ruleThickness;
}
// empty over?
if (!(bmOver.ascent + bmOver.descent)) {
overDelta1 = 0;
overDelta2 = 0;
}
nscoord dxBase = 0, dxOver = 0, dxUnder = 0;
nsAutoString valueAlign;
enum {
center,
left,
right
} alignPosition = center;
if (mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::align, valueAlign)) {
if (valueAlign.EqualsLiteral("left")) {
alignPosition = left;
} else if (valueAlign.EqualsLiteral("right")) {
alignPosition = right;
}
}
//////////
// pass 1, do what <mover> does: attach the overscript on the base
// Ad-hoc - This is to override fonts which have ready-made _accent_
// glyphs with negative lbearing and rbearing. We want to position
// the overscript ourselves
nscoord overWidth = bmOver.width;
if (!overWidth && (bmOver.rightBearing - bmOver.leftBearing > 0)) {
overWidth = bmOver.rightBearing - bmOver.leftBearing;
dxOver = -bmOver.leftBearing;
}
if (NS_MATHML_EMBELLISH_IS_ACCENTOVER(mEmbellishData.flags)) {
mBoundingMetrics.width = bmBase.width;
if (alignPosition == center) {
dxOver += correction;
}
}
else {
mBoundingMetrics.width = std::max(bmBase.width, overWidth);
if (alignPosition == center) {
dxOver += correction/2;
}
}
if (alignPosition == center) {
dxOver += (mBoundingMetrics.width - overWidth)/2;
dxBase = (mBoundingMetrics.width - bmBase.width)/2;
} else if (alignPosition == right) {
dxOver += mBoundingMetrics.width - overWidth;
dxBase = mBoundingMetrics.width - bmBase.width;
}
mBoundingMetrics.ascent =
bmBase.ascent + overDelta1 + bmOver.ascent + bmOver.descent;
mBoundingMetrics.descent = bmBase.descent;
mBoundingMetrics.leftBearing =
std::min(dxBase + bmBase.leftBearing, dxOver + bmOver.leftBearing);
mBoundingMetrics.rightBearing =
std::max(dxBase + bmBase.rightBearing, dxOver + bmOver.rightBearing);
//////////
// pass 2, do what <munder> does: attach the underscript on the previous
// result. We conceptually view the previous result as an "anynomous base"
// from where to attach the underscript. Hence if the underscript is empty,
// we should end up like <mover>. If the overscript is empty, we should
// end up like <munder>.
nsBoundingMetrics bmAnonymousBase = mBoundingMetrics;
nscoord ascentAnonymousBase =
std::max(mBoundingMetrics.ascent + overDelta2,
overSize.BlockStartAscent() + bmOver.descent +
overDelta1 + bmBase.ascent);
ascentAnonymousBase = std::max(ascentAnonymousBase,
baseSize.BlockStartAscent());
// Width of non-spacing marks is zero so use left and right bearing.
nscoord underWidth = bmUnder.width;
if (!underWidth) {
underWidth = bmUnder.rightBearing - bmUnder.leftBearing;
dxUnder = -bmUnder.leftBearing;
}
nscoord maxWidth = std::max(bmAnonymousBase.width, underWidth);
if (alignPosition == center &&
!NS_MATHML_EMBELLISH_IS_ACCENTUNDER(mEmbellishData.flags)) {
GetItalicCorrection(bmAnonymousBase, correction);
dxUnder += -correction/2;
}
nscoord dxAnonymousBase = 0;
if (alignPosition == center) {
dxUnder += (maxWidth - underWidth)/2;
dxAnonymousBase = (maxWidth - bmAnonymousBase.width)/2;
} else if (alignPosition == right) {
dxUnder += maxWidth - underWidth;
dxAnonymousBase = maxWidth - bmAnonymousBase.width;
}
// adjust the offsets of the real base and overscript since their
// final offsets should be relative to us...
dxOver += dxAnonymousBase;
dxBase += dxAnonymousBase;
mBoundingMetrics.width =
std::max(dxAnonymousBase + bmAnonymousBase.width, dxUnder + bmUnder.width);
// At this point, mBoundingMetrics.ascent = bmAnonymousBase.ascent
mBoundingMetrics.descent =
bmAnonymousBase.descent + underDelta1 + bmUnder.ascent + bmUnder.descent;
mBoundingMetrics.leftBearing =
std::min(dxAnonymousBase + bmAnonymousBase.leftBearing, dxUnder + bmUnder.leftBearing);
mBoundingMetrics.rightBearing =
std::max(dxAnonymousBase + bmAnonymousBase.rightBearing, dxUnder + bmUnder.rightBearing);
aDesiredSize.SetBlockStartAscent(ascentAnonymousBase);
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
std::max(mBoundingMetrics.descent + underDelta2,
bmAnonymousBase.descent + underDelta1 + bmUnder.ascent +
underSize.Height() - underSize.BlockStartAscent());
aDesiredSize.Height() = std::max(aDesiredSize.Height(),
aDesiredSize.BlockStartAscent() +
baseSize.Height() - baseSize.BlockStartAscent());
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
if (aPlaceOrigin) {
nscoord dy;
// place overscript
if (overFrame) {
dy = aDesiredSize.BlockStartAscent() -
mBoundingMetrics.ascent + bmOver.ascent -
overSize.BlockStartAscent();
FinishReflowChild (overFrame, PresContext(), overSize, nullptr, dxOver, dy, 0);
}
// place base
dy = aDesiredSize.BlockStartAscent() - baseSize.BlockStartAscent();
FinishReflowChild (baseFrame, PresContext(), baseSize, nullptr, dxBase, dy, 0);
// place underscript
if (underFrame) {
dy = aDesiredSize.BlockStartAscent() +
mBoundingMetrics.descent - bmUnder.descent -
underSize.BlockStartAscent();
FinishReflowChild (underFrame, PresContext(), underSize, nullptr,
dxUnder, dy, 0);
}
}
return NS_OK;
}
// exported routine that both munderover and mmultiscripts share.
// munderover uses this when movablelimits is set.
nsresult
nsMathMLmmultiscriptsFrame::PlaceMultiScript(nsPresContext* aPresContext,
nsRenderingContext& aRenderingContext,
bool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize,
nsMathMLContainerFrame* aFrame,
nscoord aUserSubScriptShift,
nscoord aUserSupScriptShift,
float aFontSizeInflation)
{
nsIAtom* tag = aFrame->GetContent()->NodeInfo()->NameAtom();
// This function deals with both munderover etc. as well as msubsup etc.
// As the former behaves identically to the later, we treat it as such
// to avoid additional checks later.
if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::mover_))
tag = nsGkAtoms::msup_;
else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munder_))
tag = nsGkAtoms::msub_;
else if (aFrame->GetContent()->IsMathMLElement(nsGkAtoms::munderover_))
tag = nsGkAtoms::msubsup_;
nsBoundingMetrics bmFrame;
nscoord minShiftFromXHeight, subDrop, supDrop;
////////////////////////////////////////
// Initialize super/sub shifts that
// depend only on the current font
////////////////////////////////////////
nsIFrame* baseFrame = aFrame->GetFirstPrincipalChild();
if (!baseFrame) {
if (tag == nsGkAtoms::mmultiscripts_)
aFrame->ReportErrorToConsole("NoBase");
else
aFrame->ReportChildCountError();
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
}
// get x-height (an ex)
const nsStyleFont* font = aFrame->StyleFont();
RefPtr<nsFontMetrics> fm;
nsLayoutUtils::GetFontMetricsForFrame(baseFrame, getter_AddRefs(fm),
aFontSizeInflation);
nscoord xHeight = fm->XHeight();
nscoord oneDevPixel = fm->AppUnitsPerDevPixel();
gfxFont* mathFont = fm->GetThebesFontGroup()->GetFirstMathFont();
// scriptspace from TeX for extra spacing after sup/subscript
nscoord scriptSpace;
if (mathFont) {
scriptSpace =
mathFont->GetMathConstant(gfxFontEntry::SpaceAfterScript, oneDevPixel);
} else {
// (0.5pt in plain TeX)
scriptSpace = nsPresContext::CSSPointsToAppUnits(0.5f);
}
// force the scriptSpace to be at least 1 pixel
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
scriptSpace = std::max(onePixel, scriptSpace);
/////////////////////////////////////
// first the shift for the subscript
nscoord subScriptShift;
if (mathFont) {
// Try and get the sub script shift from the MATH table. Note that contrary
// to TeX we only have one parameter.
subScriptShift =
mathFont->GetMathConstant(gfxFontEntry::SubscriptShiftDown, oneDevPixel);
} else {
// subScriptShift{1,2}
// = minimum amount to shift the subscript down
// = sub{1,2} in TeXbook
// subScriptShift1 = subscriptshift attribute * x-height
nscoord subScriptShift1, subScriptShift2;
// Get subScriptShift{1,2} default from font
GetSubScriptShifts (fm, subScriptShift1, subScriptShift2);
if (tag == nsGkAtoms::msub_) {
subScriptShift = subScriptShift1;
} else {
subScriptShift = std::max(subScriptShift1, subScriptShift2);
}
}
if (0 < aUserSubScriptShift) {
// the user has set the subscriptshift attribute
subScriptShift = std::max(subScriptShift, aUserSubScriptShift);
}
/////////////////////////////////////
// next the shift for the superscript
nscoord supScriptShift;
nsPresentationData presentationData;
aFrame->GetPresentationData(presentationData);
if (mathFont) {
// Try and get the super script shift from the MATH table. Note that
// contrary to TeX we only have two parameters.
supScriptShift = mathFont->
GetMathConstant(NS_MATHML_IS_COMPRESSED(presentationData.flags) ?
gfxFontEntry::SuperscriptShiftUpCramped :
gfxFontEntry::SuperscriptShiftUp,
oneDevPixel);
} else {
// supScriptShift{1,2,3}
// = minimum amount to shift the supscript up
// = sup{1,2,3} in TeX
// supScriptShift1 = superscriptshift attribute * x-height
// Note that there are THREE values for supscript shifts depending
// on the current style
nscoord supScriptShift1, supScriptShift2, supScriptShift3;
// Set supScriptShift{1,2,3} default from font
GetSupScriptShifts (fm, supScriptShift1, supScriptShift2, supScriptShift3);
// get sup script shift depending on current script level and display style
// Rule 18c, App. G, TeXbook
if (font->mScriptLevel == 0 &&
font->mMathDisplay == NS_MATHML_DISPLAYSTYLE_BLOCK &&
!NS_MATHML_IS_COMPRESSED(presentationData.flags)) {
// Style D in TeXbook
supScriptShift = supScriptShift1;
} else if (NS_MATHML_IS_COMPRESSED(presentationData.flags)) {
// Style C' in TeXbook = D',T',S',SS'
supScriptShift = supScriptShift3;
} else {
// everything else = T,S,SS
supScriptShift = supScriptShift2;
}
}
if (0 < aUserSupScriptShift) {
// the user has set the supscriptshift attribute
supScriptShift = std::max(supScriptShift, aUserSupScriptShift);
}
////////////////////////////////////
// Get the children's sizes
////////////////////////////////////
const WritingMode wm(aDesiredSize.GetWritingMode());
nscoord width = 0, prescriptsWidth = 0, rightBearing = 0;
nscoord minSubScriptShift = 0, minSupScriptShift = 0;
nscoord trySubScriptShift = subScriptShift;
nscoord trySupScriptShift = supScriptShift;
nscoord maxSubScriptShift = subScriptShift;
nscoord maxSupScriptShift = supScriptShift;
nsHTMLReflowMetrics baseSize(wm);
nsHTMLReflowMetrics subScriptSize(wm);
nsHTMLReflowMetrics supScriptSize(wm);
nsHTMLReflowMetrics multiSubSize(wm), multiSupSize(wm);
baseFrame = nullptr;
nsIFrame* subScriptFrame = nullptr;
nsIFrame* supScriptFrame = nullptr;
nsIFrame* prescriptsFrame = nullptr; // frame of <mprescripts/>, if there.
bool firstPrescriptsPair = false;
nsBoundingMetrics bmBase, bmSubScript, bmSupScript, bmMultiSub, bmMultiSup;
multiSubSize.SetBlockStartAscent(-0x7FFFFFFF);
multiSupSize.SetBlockStartAscent(-0x7FFFFFFF);
bmMultiSub.ascent = bmMultiSup.ascent = -0x7FFFFFFF;
bmMultiSub.descent = bmMultiSup.descent = -0x7FFFFFFF;
nscoord italicCorrection = 0;
nsBoundingMetrics boundingMetrics;
boundingMetrics.width = 0;
boundingMetrics.ascent = boundingMetrics.descent = -0x7FFFFFFF;
aDesiredSize.Width() = aDesiredSize.Height() = 0;
int32_t count = 0;
bool foundNoneTag = false;
// Boolean to determine whether the current child is a subscript.
// Note that only msup starts with a superscript.
bool isSubScript = (tag != nsGkAtoms::msup_);
nsIFrame* childFrame = aFrame->GetFirstPrincipalChild();
while (childFrame) {
if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::mprescripts_)) {
if (tag != nsGkAtoms::mmultiscripts_) {
if (aPlaceOrigin) {
aFrame->ReportInvalidChildError(nsGkAtoms::mprescripts_);
}
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
}
if (prescriptsFrame) {
// duplicate <mprescripts/> found
// report an error, encourage people to get their markups in order
if (aPlaceOrigin) {
aFrame->ReportErrorToConsole("DuplicateMprescripts");
}
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
}
if (!isSubScript) {
if (aPlaceOrigin) {
aFrame->ReportErrorToConsole("SubSupMismatch");
}
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
}
prescriptsFrame = childFrame;
firstPrescriptsPair = true;
} else if (0 == count) {
// base
if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::none)) {
if (tag == nsGkAtoms::mmultiscripts_) {
if (aPlaceOrigin) {
aFrame->ReportErrorToConsole("NoBase");
}
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
} else {
//A different error message is triggered later for the other tags
foundNoneTag = true;
}
}
baseFrame = childFrame;
GetReflowAndBoundingMetricsFor(baseFrame, baseSize, bmBase);
if (tag != nsGkAtoms::msub_) {
// Apply italics correction if there is the potential for a
// postsupscript.
GetItalicCorrection(bmBase, italicCorrection);
// If italics correction is applied, we always add "a little to spare"
// (see TeXbook Ch.11, p.64), as we estimate the italic creation
// ourselves and it isn't the same as TeX.
italicCorrection += onePixel;
}
// we update boundingMetrics.{ascent,descent} with that
// of the baseFrame only after processing all the sup/sub pairs
boundingMetrics.width = bmBase.width;
boundingMetrics.rightBearing = bmBase.rightBearing;
boundingMetrics.leftBearing = bmBase.leftBearing; // until overwritten
} else {
// super/subscript block
if (childFrame->GetContent()->IsMathMLElement(nsGkAtoms::none)) {
foundNoneTag = true;
}
if (isSubScript) {
// subscript
subScriptFrame = childFrame;
GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, bmSubScript);
// get the subdrop from the subscript font
GetSubDropFromChild (subScriptFrame, subDrop, aFontSizeInflation);
// parameter v, Rule 18a, App. G, TeXbook
minSubScriptShift = bmBase.descent + subDrop;
trySubScriptShift = std::max(minSubScriptShift,subScriptShift);
multiSubSize.SetBlockStartAscent(
std::max(multiSubSize.BlockStartAscent(),
subScriptSize.BlockStartAscent()));
bmMultiSub.ascent = std::max(bmMultiSub.ascent, bmSubScript.ascent);
bmMultiSub.descent = std::max(bmMultiSub.descent, bmSubScript.descent);
multiSubSize.Height() =
std::max(multiSubSize.Height(),
subScriptSize.Height() - subScriptSize.BlockStartAscent());
if (bmSubScript.width)
width = bmSubScript.width + scriptSpace;
rightBearing = bmSubScript.rightBearing;
if (tag == nsGkAtoms::msub_) {
boundingMetrics.rightBearing = boundingMetrics.width + rightBearing;
boundingMetrics.width += width;
nscoord subscriptTopMax;
if (mathFont) {
subscriptTopMax =
mathFont->GetMathConstant(gfxFontEntry::SubscriptTopMax,
oneDevPixel);
} else {
// get min subscript shift limit from x-height
// = h(x) - 4/5 * sigma_5, Rule 18b, App. G, TeXbook
subscriptTopMax = NSToCoordRound((4.0f/5.0f) * xHeight);
}
nscoord minShiftFromXHeight = bmSubScript.ascent - subscriptTopMax;
maxSubScriptShift = std::max(trySubScriptShift,minShiftFromXHeight);
maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift);
trySubScriptShift = subScriptShift;
}
} else {
// supscript
supScriptFrame = childFrame;
GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, bmSupScript);
// get the supdrop from the supscript font
GetSupDropFromChild (supScriptFrame, supDrop, aFontSizeInflation);
// parameter u, Rule 18a, App. G, TeXbook
minSupScriptShift = bmBase.ascent - supDrop;
nscoord superscriptBottomMin;
if (mathFont) {
superscriptBottomMin =
mathFont->GetMathConstant(gfxFontEntry::SuperscriptBottomMin,
oneDevPixel);
} else {
// get min supscript shift limit from x-height
// = d(x) + 1/4 * sigma_5, Rule 18c, App. G, TeXbook
superscriptBottomMin = NSToCoordRound((1.0f / 4.0f) * xHeight);
}
minShiftFromXHeight = bmSupScript.descent + superscriptBottomMin;
trySupScriptShift = std::max(minSupScriptShift,
std::max(minShiftFromXHeight,
supScriptShift));
multiSupSize.SetBlockStartAscent(
std::max(multiSupSize.BlockStartAscent(),
supScriptSize.BlockStartAscent()));
bmMultiSup.ascent = std::max(bmMultiSup.ascent, bmSupScript.ascent);
bmMultiSup.descent = std::max(bmMultiSup.descent, bmSupScript.descent);
multiSupSize.Height() =
std::max(multiSupSize.Height(),
supScriptSize.Height() - supScriptSize.BlockStartAscent());
if (bmSupScript.width)
width = std::max(width, bmSupScript.width + scriptSpace);
if (!prescriptsFrame) { // we are still looping over base & postscripts
rightBearing = std::max(rightBearing,
italicCorrection + bmSupScript.rightBearing);
boundingMetrics.rightBearing = boundingMetrics.width + rightBearing;
boundingMetrics.width += width;
} else {
prescriptsWidth += width;
if (firstPrescriptsPair) {
firstPrescriptsPair = false;
boundingMetrics.leftBearing =
std::min(bmSubScript.leftBearing, bmSupScript.leftBearing);
}
}
width = rightBearing = 0;
// negotiate between the various shifts so that
// there is enough gap between the sup and subscripts
// Rule 18e, App. G, TeXbook
if (tag == nsGkAtoms::mmultiscripts_ ||
tag == nsGkAtoms::msubsup_) {
nscoord subSuperscriptGapMin;
if (mathFont) {
subSuperscriptGapMin =
mathFont->GetMathConstant(gfxFontEntry::SubSuperscriptGapMin,
oneDevPixel);
} else {
nscoord ruleSize;
GetRuleThickness(aRenderingContext, fm, ruleSize);
subSuperscriptGapMin = 4 * ruleSize;
}
nscoord gap =
(trySupScriptShift - bmSupScript.descent) -
(bmSubScript.ascent - trySubScriptShift);
if (gap < subSuperscriptGapMin) {
// adjust trySubScriptShift to get a gap of subSuperscriptGapMin
trySubScriptShift += subSuperscriptGapMin - gap;
}
// next we want to ensure that the bottom of the superscript
// will be > superscriptBottomMaxWithSubscript
nscoord superscriptBottomMaxWithSubscript;
if (mathFont) {
superscriptBottomMaxWithSubscript = mathFont->
GetMathConstant(gfxFontEntry::SuperscriptBottomMaxWithSubscript,
oneDevPixel);
} else {
superscriptBottomMaxWithSubscript =
NSToCoordRound((4.0f / 5.0f) * xHeight);
}
gap = superscriptBottomMaxWithSubscript -
(trySupScriptShift - bmSupScript.descent);
if (gap > 0) {
trySupScriptShift += gap;
trySubScriptShift -= gap;
}
}
maxSubScriptShift = std::max(maxSubScriptShift, trySubScriptShift);
maxSupScriptShift = std::max(maxSupScriptShift, trySupScriptShift);
trySubScriptShift = subScriptShift;
trySupScriptShift = supScriptShift;
}
isSubScript = !isSubScript;
}
count++;
childFrame = childFrame->GetNextSibling();
}
//NoBase error may also have been reported above
if ((count != 2 && (tag == nsGkAtoms::msup_ || tag == nsGkAtoms::msub_)) ||
(count != 3 && tag == nsGkAtoms::msubsup_) || !baseFrame ||
(foundNoneTag && tag != nsGkAtoms::mmultiscripts_) ||
(!isSubScript && tag == nsGkAtoms::mmultiscripts_)) {
// report an error, encourage people to get their markups in order
if (aPlaceOrigin) {
if ((count != 2 && (tag == nsGkAtoms::msup_ ||
tag == nsGkAtoms::msub_)) ||
(count != 3 && tag == nsGkAtoms::msubsup_ )) {
aFrame->ReportChildCountError();
} else if (foundNoneTag && tag != nsGkAtoms::mmultiscripts_) {
aFrame->ReportInvalidChildError(nsGkAtoms::none);
} else if (!baseFrame) {
aFrame->ReportErrorToConsole("NoBase");
} else {
aFrame->ReportErrorToConsole("SubSupMismatch");
}
}
return aFrame->ReflowError(aRenderingContext, aDesiredSize);
}
// we left out the width of prescripts, so ...
boundingMetrics.rightBearing += prescriptsWidth;
boundingMetrics.width += prescriptsWidth;
// Zero out the shifts in where a frame isn't present to avoid the potential
// for overflow.
if (!subScriptFrame)
maxSubScriptShift = 0;
if (!supScriptFrame)
maxSupScriptShift = 0;
// we left out the base during our bounding box updates, so ...
if (tag == nsGkAtoms::msub_) {
boundingMetrics.ascent = std::max(bmBase.ascent,
bmMultiSub.ascent - maxSubScriptShift);
} else {
boundingMetrics.ascent =
std::max(bmBase.ascent, (bmMultiSup.ascent + maxSupScriptShift));
}
if (tag == nsGkAtoms::msup_) {
boundingMetrics.descent = std::max(bmBase.descent,
bmMultiSup.descent - maxSupScriptShift);
} else {
boundingMetrics.descent =
std::max(bmBase.descent, (bmMultiSub.descent + maxSubScriptShift));
}
aFrame->SetBoundingMetrics(boundingMetrics);
// get the reflow metrics ...
aDesiredSize.SetBlockStartAscent(
std::max(baseSize.BlockStartAscent(),
std::max(multiSubSize.BlockStartAscent() - maxSubScriptShift,
multiSupSize.BlockStartAscent() + maxSupScriptShift)));
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
std::max(baseSize.Height() - baseSize.BlockStartAscent(),
std::max(multiSubSize.Height() + maxSubScriptShift,
multiSupSize.Height() - maxSupScriptShift));
aDesiredSize.Width() = boundingMetrics.width;
aDesiredSize.mBoundingMetrics = boundingMetrics;
aFrame->SetReference(nsPoint(0, aDesiredSize.BlockStartAscent()));
//////////////////
// Place Children
// Place prescripts, followed by base, and then postscripts.
// The list of frames is in the order: {base} {postscripts} {prescripts}
// We go over the list in a circular manner, starting at <prescripts/>
if (aPlaceOrigin) {
nscoord dx = 0, dy = 0;
// With msub and msup there is only one element and
// subscriptFrame/supScriptFrame have already been set above where
// relevant. In these cases we skip to the reflow part.
if (tag == nsGkAtoms::msub_ || tag == nsGkAtoms::msup_)
count = 1;
else
count = 0;
childFrame = prescriptsFrame;
bool isPreScript = true;
do {
if (!childFrame) { // end of prescripts,
isPreScript = false;
// place the base ...
childFrame = baseFrame;
dy = aDesiredSize.BlockStartAscent() - baseSize.BlockStartAscent();
FinishReflowChild (baseFrame, aPresContext, baseSize, nullptr,
aFrame->MirrorIfRTL(aDesiredSize.Width(),
baseSize.Width(),
dx),
dy, 0);
dx += bmBase.width;
} else if (prescriptsFrame == childFrame) {
// Clear reflow flags of prescripts frame.
prescriptsFrame->DidReflow(aPresContext, nullptr, nsDidReflowStatus::FINISHED);
} else {
// process each sup/sub pair
if (0 == count) {
subScriptFrame = childFrame;
count = 1;
} else if (1 == count) {
if (tag != nsGkAtoms::msub_)
supScriptFrame = childFrame;
count = 0;
// get the ascent/descent of sup/subscripts stored in their rects
// rect.x = descent, rect.y = ascent
if (subScriptFrame)
GetReflowAndBoundingMetricsFor(subScriptFrame, subScriptSize, bmSubScript);
if (supScriptFrame)
GetReflowAndBoundingMetricsFor(supScriptFrame, supScriptSize, bmSupScript);
width = std::max(subScriptSize.Width(), supScriptSize.Width());
if (subScriptFrame) {
nscoord x = dx;
// prescripts should be right aligned
// https://bugzilla.mozilla.org/show_bug.cgi?id=928675
if (isPreScript)
x += width - subScriptSize.Width();
dy = aDesiredSize.BlockStartAscent() - subScriptSize.BlockStartAscent() +
maxSubScriptShift;
FinishReflowChild (subScriptFrame, aPresContext, subScriptSize,
nullptr,
aFrame->MirrorIfRTL(aDesiredSize.Width(),
subScriptSize.Width(),
x),
dy, 0);
}
if (supScriptFrame) {
nscoord x = dx;
if (isPreScript) {
x += width - supScriptSize.Width();
} else {
// post superscripts are shifted by the italic correction value
x += italicCorrection;
}
dy = aDesiredSize.BlockStartAscent() - supScriptSize.BlockStartAscent() -
maxSupScriptShift;
FinishReflowChild (supScriptFrame, aPresContext, supScriptSize,
nullptr,
aFrame->MirrorIfRTL(aDesiredSize.Width(),
supScriptSize.Width(),
x),
dy, 0);
}
dx += width + scriptSpace;
}
}
childFrame = childFrame->GetNextSibling();
} while (prescriptsFrame != childFrame);
}
return NS_OK;
}
nsresult
nsMathMLmfracFrame::PlaceInternal(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize,
bool aWidthOnly)
{
////////////////////////////////////
// Get the children's desired sizes
nsBoundingMetrics bmNum, bmDen;
ReflowOutput sizeNum(aDesiredSize.GetWritingMode());
ReflowOutput sizeDen(aDesiredSize.GetWritingMode());
nsIFrame* frameDen = nullptr;
nsIFrame* frameNum = mFrames.FirstChild();
if (frameNum)
frameDen = frameNum->GetNextSibling();
if (!frameNum || !frameDen || frameDen->GetNextSibling()) {
// report an error, encourage people to get their markups in order
if (aPlaceOrigin) {
ReportChildCountError();
}
return ReflowError(aDrawTarget, aDesiredSize);
}
GetReflowAndBoundingMetricsFor(frameNum, sizeNum, bmNum);
GetReflowAndBoundingMetricsFor(frameDen, sizeDen, bmDen);
nsPresContext* presContext = PresContext();
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetFontMetricsForFrame(this, fontSizeInflation);
nscoord defaultRuleThickness, axisHeight;
nscoord oneDevPixel = fm->AppUnitsPerDevPixel();
gfxFont* mathFont = fm->GetThebesFontGroup()->GetFirstMathFont();
if (mathFont) {
defaultRuleThickness =
mathFont->GetMathConstant(gfxFontEntry::FractionRuleThickness,
oneDevPixel);
} else {
GetRuleThickness(aDrawTarget, fm, defaultRuleThickness);
}
GetAxisHeight(aDrawTarget, fm, axisHeight);
bool outermostEmbellished = false;
if (mEmbellishData.coreFrame) {
nsEmbellishData parentData;
GetEmbellishDataFrom(GetParent(), parentData);
outermostEmbellished = parentData.coreFrame != mEmbellishData.coreFrame;
}
// see if the linethickness attribute is there
nsAutoString value;
mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::linethickness_, value);
mLineThickness = CalcLineThickness(presContext, mStyleContext, value,
onePixel, defaultRuleThickness,
fontSizeInflation);
// bevelled attribute
mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::bevelled_, value);
mIsBevelled = value.EqualsLiteral("true");
bool displayStyle = StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_BLOCK;
if (!mIsBevelled) {
mLineRect.height = mLineThickness;
// by default, leave at least one-pixel padding at either end, and add
// lspace & rspace that may come from <mo> if we are an outermost
// embellished container (we fetch values from the core since they may use
// units that depend on style data, and style changes could have occurred
// in the core since our last visit there)
nscoord leftSpace = onePixel;
nscoord rightSpace = onePixel;
if (outermostEmbellished) {
nsEmbellishData coreData;
GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
leftSpace += StyleVisibility()->mDirection ?
coreData.trailingSpace : coreData.leadingSpace;
rightSpace += StyleVisibility()->mDirection ?
coreData.leadingSpace : coreData.trailingSpace;
}
nscoord actualRuleThickness = mLineThickness;
//////////////////
// Get shifts
nscoord numShift = 0;
nscoord denShift = 0;
// Rule 15b, App. G, TeXbook
nscoord numShift1, numShift2, numShift3;
nscoord denShift1, denShift2;
GetNumeratorShifts(fm, numShift1, numShift2, numShift3);
GetDenominatorShifts(fm, denShift1, denShift2);
if (0 == actualRuleThickness) {
numShift = displayStyle ? numShift1 : numShift3;
denShift = displayStyle ? denShift1 : denShift2;
if (mathFont) {
numShift = mathFont->
GetMathConstant(displayStyle ?
gfxFontEntry::StackTopDisplayStyleShiftUp :
gfxFontEntry::StackTopShiftUp,
oneDevPixel);
denShift = mathFont->
GetMathConstant(displayStyle ?
gfxFontEntry::StackBottomDisplayStyleShiftDown :
gfxFontEntry::StackBottomShiftDown,
oneDevPixel);
}
} else {
numShift = displayStyle ? numShift1 : numShift2;
denShift = displayStyle ? denShift1 : denShift2;
if (mathFont) {
numShift = mathFont->
GetMathConstant(displayStyle ?
gfxFontEntry::FractionNumeratorDisplayStyleShiftUp :
gfxFontEntry::FractionNumeratorShiftUp,
oneDevPixel);
denShift = mathFont->
GetMathConstant(
displayStyle ?
gfxFontEntry::FractionDenominatorDisplayStyleShiftDown :
gfxFontEntry::FractionDenominatorShiftDown,
oneDevPixel);
}
}
if (0 == actualRuleThickness) {
// Rule 15c, App. G, TeXbook
// min clearance between numerator and denominator
nscoord minClearance = displayStyle ?
7 * defaultRuleThickness : 3 * defaultRuleThickness;
if (mathFont) {
minClearance =
mathFont->GetMathConstant(displayStyle ?
gfxFontEntry::StackDisplayStyleGapMin :
gfxFontEntry::StackGapMin,
oneDevPixel);
}
// Factor in axis height
// http://www.mathml-association.org/MathMLinHTML5/S3.html#SS3.SSS2
numShift += axisHeight;
denShift += axisHeight;
nscoord actualClearance =
(numShift - bmNum.descent) - (bmDen.ascent - denShift);
// actualClearance should be >= minClearance
if (actualClearance < minClearance) {
nscoord halfGap = (minClearance - actualClearance)/2;
numShift += halfGap;
denShift += halfGap;
}
}
else {
// Rule 15d, App. G, TeXbook
// min clearance between numerator or denominator and middle of bar
// TeX has a different interpretation of the thickness.
// Try $a \above10pt b$ to see. Here is what TeX does:
// minClearance = displayStyle ?
// 3 * actualRuleThickness : actualRuleThickness;
// we slightly depart from TeX here. We use the defaultRuleThickness instead
// of the value coming from the linethickness attribute, i.e., we recover what
// TeX does if the user hasn't set linethickness. But when the linethickness
// is set, we avoid the wide gap problem.
nscoord minClearanceNum = displayStyle ?
3 * defaultRuleThickness : defaultRuleThickness + onePixel;
nscoord minClearanceDen = minClearanceNum;
if (mathFont) {
minClearanceNum = mathFont->
GetMathConstant(displayStyle ?
gfxFontEntry::FractionNumDisplayStyleGapMin :
gfxFontEntry::FractionNumeratorGapMin,
oneDevPixel);
minClearanceDen = mathFont->
GetMathConstant(displayStyle ?
gfxFontEntry::FractionDenomDisplayStyleGapMin :
gfxFontEntry::FractionDenominatorGapMin,
oneDevPixel);
}
// adjust numShift to maintain minClearanceNum if needed
nscoord actualClearanceNum =
(numShift - bmNum.descent) - (axisHeight + actualRuleThickness/2);
if (actualClearanceNum < minClearanceNum) {
numShift += (minClearanceNum - actualClearanceNum);
}
// adjust denShift to maintain minClearanceDen if needed
nscoord actualClearanceDen =
(axisHeight - actualRuleThickness/2) - (bmDen.ascent - denShift);
if (actualClearanceDen < minClearanceDen) {
denShift += (minClearanceDen - actualClearanceDen);
}
}
//////////////////
// Place Children
// XXX Need revisiting the width. TeX uses the exact width
// e.g. in $$\huge\frac{\displaystyle\int}{i}$$
nscoord width = std::max(bmNum.width, bmDen.width);
nscoord dxNum = leftSpace + (width - sizeNum.Width())/2;
nscoord dxDen = leftSpace + (width - sizeDen.Width())/2;
width += leftSpace + rightSpace;
// see if the numalign attribute is there
mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::numalign_, value);
if (value.EqualsLiteral("left"))
dxNum = leftSpace;
else if (value.EqualsLiteral("right"))
dxNum = width - rightSpace - sizeNum.Width();
// see if the denomalign attribute is there
mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::denomalign_, value);
if (value.EqualsLiteral("left"))
dxDen = leftSpace;
else if (value.EqualsLiteral("right"))
dxDen = width - rightSpace - sizeDen.Width();
mBoundingMetrics.rightBearing =
std::max(dxNum + bmNum.rightBearing, dxDen + bmDen.rightBearing);
if (mBoundingMetrics.rightBearing < width - rightSpace)
mBoundingMetrics.rightBearing = width - rightSpace;
mBoundingMetrics.leftBearing =
std::min(dxNum + bmNum.leftBearing, dxDen + bmDen.leftBearing);
if (mBoundingMetrics.leftBearing > leftSpace)
mBoundingMetrics.leftBearing = leftSpace;
mBoundingMetrics.ascent = bmNum.ascent + numShift;
mBoundingMetrics.descent = bmDen.descent + denShift;
mBoundingMetrics.width = width;
aDesiredSize.SetBlockStartAscent(sizeNum.BlockStartAscent() + numShift);
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
sizeDen.Height() - sizeDen.BlockStartAscent() + denShift;
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
if (aPlaceOrigin) {
nscoord dy;
// place numerator
dy = 0;
FinishReflowChild(frameNum, presContext, sizeNum, nullptr, dxNum, dy, 0);
// place denominator
dy = aDesiredSize.Height() - sizeDen.Height();
FinishReflowChild(frameDen, presContext, sizeDen, nullptr, dxDen, dy, 0);
// place the fraction bar - dy is top of bar
dy = aDesiredSize.BlockStartAscent() - (axisHeight + actualRuleThickness/2);
mLineRect.SetRect(leftSpace, dy, width - (leftSpace + rightSpace),
actualRuleThickness);
}
} else {
nscoord numShift = 0.0;
nscoord denShift = 0.0;
nscoord padding = 3 * defaultRuleThickness;
nscoord slashRatio = 3;
// Define the constant used in the expression of the maximum width
nscoord em = fm->EmHeight();
nscoord slashMaxWidthConstant = 2 * em;
// For large line thicknesses the minimum slash height is limited to the
// largest expected height of a fraction
nscoord slashMinHeight = slashRatio *
std::min(2 * mLineThickness, slashMaxWidthConstant);
nscoord leadingSpace = padding;
nscoord trailingSpace = padding;
if (outermostEmbellished) {
nsEmbellishData coreData;
GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
leadingSpace += coreData.leadingSpace;
trailingSpace += coreData.trailingSpace;
}
nscoord delta;
// ___________
// | | /
// {|-NUMERATOR-| /
// {|___________| S
// { L
// numShift{ A
// ------------------------------------------------------- baseline
// S _____________ } denShift
// H | |}
// / |-DENOMINATOR-|}
// / |_____________|
//
// first, ensure that the top of the numerator is at least as high as the
// top of the denominator (and the reverse for the bottoms)
delta = std::max(bmDen.ascent - bmNum.ascent,
bmNum.descent - bmDen.descent) / 2;
if (delta > 0) {
numShift += delta;
denShift += delta;
}
if (StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_BLOCK) {
delta = std::min(bmDen.ascent + bmDen.descent,
bmNum.ascent + bmNum.descent) / 2;
numShift += delta;
denShift += delta;
} else {
nscoord xHeight = fm->XHeight();
numShift += xHeight / 2;
denShift += xHeight / 4;
}
// Set the ascent/descent of our BoundingMetrics.
mBoundingMetrics.ascent = bmNum.ascent + numShift;
mBoundingMetrics.descent = bmDen.descent + denShift;
// At this point the height of the slash is
// mBoundingMetrics.ascent + mBoundingMetrics.descent
// Ensure that it is greater than slashMinHeight
delta = (slashMinHeight -
(mBoundingMetrics.ascent + mBoundingMetrics.descent)) / 2;
if (delta > 0) {
mBoundingMetrics.ascent += delta;
mBoundingMetrics.descent += delta;
}
// Set the width of the slash
if (aWidthOnly) {
mLineRect.width = mLineThickness + slashMaxWidthConstant;
} else {
mLineRect.width = mLineThickness +
std::min(slashMaxWidthConstant,
(mBoundingMetrics.ascent + mBoundingMetrics.descent) /
slashRatio);
}
// Set horizontal bounding metrics
if (StyleVisibility()->mDirection) {
mBoundingMetrics.leftBearing = trailingSpace + bmDen.leftBearing;
mBoundingMetrics.rightBearing = trailingSpace + bmDen.width + mLineRect.width + bmNum.rightBearing;
} else {
mBoundingMetrics.leftBearing = leadingSpace + bmNum.leftBearing;
mBoundingMetrics.rightBearing = leadingSpace + bmNum.width + mLineRect.width + bmDen.rightBearing;
}
mBoundingMetrics.width =
leadingSpace + bmNum.width + mLineRect.width + bmDen.width +
trailingSpace;
// Set aDesiredSize
aDesiredSize.SetBlockStartAscent(mBoundingMetrics.ascent + padding);
aDesiredSize.Height() =
mBoundingMetrics.ascent + mBoundingMetrics.descent + 2 * padding;
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
if (aPlaceOrigin) {
nscoord dx, dy;
// place numerator
dx = MirrorIfRTL(aDesiredSize.Width(), sizeNum.Width(),
leadingSpace);
dy = aDesiredSize.BlockStartAscent() - numShift - sizeNum.BlockStartAscent();
FinishReflowChild(frameNum, presContext, sizeNum, nullptr, dx, dy, 0);
// place the fraction bar
dx = MirrorIfRTL(aDesiredSize.Width(), mLineRect.width,
leadingSpace + bmNum.width);
dy = aDesiredSize.BlockStartAscent() - mBoundingMetrics.ascent;
mLineRect.SetRect(dx, dy,
mLineRect.width, aDesiredSize.Height() - 2 * padding);
// place denominator
dx = MirrorIfRTL(aDesiredSize.Width(), sizeDen.Width(),
leadingSpace + bmNum.width + mLineRect.width);
dy = aDesiredSize.BlockStartAscent() + denShift - sizeDen.BlockStartAscent();
FinishReflowChild(frameDen, presContext, sizeDen, nullptr, dx, dy, 0);
}
}
return NS_OK;
}