void
nsMathMLmpaddedFrame::UpdateValue(int32_t aSign,
int32_t aPseudoUnit,
const nsCSSValue& aCSSValue,
const ReflowOutput& aDesiredSize,
nscoord& aValueToUpdate,
float aFontSizeInflation) const
{
nsCSSUnit unit = aCSSValue.GetUnit();
if (NS_MATHML_SIGN_INVALID != aSign && eCSSUnit_Null != unit) {
nscoord scaler = 0, amount = 0;
if (eCSSUnit_Percent == unit || eCSSUnit_Number == unit) {
switch(aPseudoUnit) {
case NS_MATHML_PSEUDO_UNIT_WIDTH:
scaler = aDesiredSize.Width();
break;
case NS_MATHML_PSEUDO_UNIT_HEIGHT:
scaler = aDesiredSize.BlockStartAscent();
break;
case NS_MATHML_PSEUDO_UNIT_DEPTH:
scaler = aDesiredSize.Height() - aDesiredSize.BlockStartAscent();
break;
default:
// if we ever reach here, it would mean something is wrong
// somewhere with the setup and/or the caller
NS_ERROR("Unexpected Pseudo Unit");
return;
}
}
if (eCSSUnit_Number == unit)
amount = NSToCoordRound(float(scaler) * aCSSValue.GetFloatValue());
else if (eCSSUnit_Percent == unit)
amount = NSToCoordRound(float(scaler) * aCSSValue.GetPercentValue());
else
amount = CalcLength(PresContext(), mStyleContext, aCSSValue,
aFontSizeInflation);
if (NS_MATHML_SIGN_PLUS == aSign)
aValueToUpdate += amount;
else if (NS_MATHML_SIGN_MINUS == aSign)
aValueToUpdate -= amount;
else
aValueToUpdate = amount;
}
}
// Only place the selected child ...
/* virtual */ nsresult
nsMathMLSelectedFrame::Place(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize)
{
nsIFrame* childFrame = GetSelectedFrame();
if (mInvalidMarkup) {
return ReflowError(aDrawTarget, aDesiredSize);
}
aDesiredSize.ClearSize();
aDesiredSize.SetBlockStartAscent(0);
mBoundingMetrics = nsBoundingMetrics();
if (childFrame) {
GetReflowAndBoundingMetricsFor(childFrame, aDesiredSize, mBoundingMetrics);
if (aPlaceOrigin) {
FinishReflowChild(childFrame, PresContext(), aDesiredSize, nullptr, 0, 0, 0);
}
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
}
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
return NS_OK;
}
/* virtual */ nsresult
nsMathMLmpaddedFrame::Place(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize)
{
nsresult rv =
nsMathMLContainerFrame::Place(aDrawTarget, false, aDesiredSize);
if (NS_MATHML_HAS_ERROR(mPresentationData.flags) || NS_FAILED(rv)) {
DidReflowChildren(PrincipalChildList().FirstChild());
return rv;
}
nscoord height = aDesiredSize.BlockStartAscent();
nscoord depth = aDesiredSize.Height() - aDesiredSize.BlockStartAscent();
// The REC says:
//
// "The lspace attribute ('leading' space) specifies the horizontal location
// of the positioning point of the child content with respect to the
// positioning point of the mpadded element. By default they coincide, and
// therefore absolute values for lspace have the same effect as relative
// values."
//
// "MathML renderers should ensure that, except for the effects of the
// attributes, the relative spacing between the contents of the mpadded
// element and surrounding MathML elements would not be modified by replacing
// an mpadded element with an mrow element with the same content, even if
// linebreaking occurs within the mpadded element."
//
// (http://www.w3.org/TR/MathML/chapter3.html#presm.mpadded)
//
// "In those discussions, the terms leading and trailing are used to specify
// a side of an object when which side to use depends on the directionality;
// ie. leading means left in LTR but right in RTL."
// (http://www.w3.org/TR/MathML/chapter3.html#presm.bidi.math)
nscoord lspace = 0;
// In MathML3, "width" will be the bounding box width and "advancewidth" will
// refer "to the horizontal distance between the positioning point of the
// mpadded and the positioning point for the following content". MathML2
// doesn't make the distinction.
nscoord width = aDesiredSize.Width();
nscoord voffset = 0;
int32_t pseudoUnit;
nscoord initialWidth = width;
float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
// update width
pseudoUnit = (mWidthPseudoUnit == NS_MATHML_PSEUDO_UNIT_ITSELF)
? NS_MATHML_PSEUDO_UNIT_WIDTH : mWidthPseudoUnit;
UpdateValue(mWidthSign, pseudoUnit, mWidth,
aDesiredSize, width, fontSizeInflation);
width = std::max(0, width);
// update "height" (this is the ascent in the terminology of the REC)
pseudoUnit = (mHeightPseudoUnit == NS_MATHML_PSEUDO_UNIT_ITSELF)
? NS_MATHML_PSEUDO_UNIT_HEIGHT : mHeightPseudoUnit;
UpdateValue(mHeightSign, pseudoUnit, mHeight,
aDesiredSize, height, fontSizeInflation);
height = std::max(0, height);
// update "depth" (this is the descent in the terminology of the REC)
pseudoUnit = (mDepthPseudoUnit == NS_MATHML_PSEUDO_UNIT_ITSELF)
? NS_MATHML_PSEUDO_UNIT_DEPTH : mDepthPseudoUnit;
UpdateValue(mDepthSign, pseudoUnit, mDepth,
aDesiredSize, depth, fontSizeInflation);
depth = std::max(0, depth);
// update lspace
if (mLeadingSpacePseudoUnit != NS_MATHML_PSEUDO_UNIT_ITSELF) {
pseudoUnit = mLeadingSpacePseudoUnit;
UpdateValue(mLeadingSpaceSign, pseudoUnit, mLeadingSpace,
aDesiredSize, lspace, fontSizeInflation);
}
// update voffset
if (mVerticalOffsetPseudoUnit != NS_MATHML_PSEUDO_UNIT_ITSELF) {
pseudoUnit = mVerticalOffsetPseudoUnit;
UpdateValue(mVerticalOffsetSign, pseudoUnit, mVerticalOffset,
aDesiredSize, voffset, fontSizeInflation);
}
// do the padding now that we have everything
// The idea here is to maintain the invariant that <mpadded>...</mpadded> (i.e.,
// with no attributes) looks the same as <mrow>...</mrow>. But when there are
// attributes, tweak our metrics and move children to achieve the desired visual
// effects.
if ((StyleVisibility()->mDirection ?
mWidthSign : mLeadingSpaceSign) != NS_MATHML_SIGN_INVALID) {
// there was padding on the left. dismiss the left italic correction now
// (so that our parent won't correct us)
mBoundingMetrics.leftBearing = 0;
}
if ((StyleVisibility()->mDirection ?
mLeadingSpaceSign : mWidthSign) != NS_MATHML_SIGN_INVALID) {
// there was padding on the right. dismiss the right italic correction now
// (so that our parent won't correct us)
mBoundingMetrics.width = width;
mBoundingMetrics.rightBearing = mBoundingMetrics.width;
}
nscoord dx = (StyleVisibility()->mDirection ?
width - initialWidth - lspace : lspace);
aDesiredSize.SetBlockStartAscent(height);
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.Height() = depth + aDesiredSize.BlockStartAscent();
mBoundingMetrics.ascent = height;
mBoundingMetrics.descent = depth;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
if (aPlaceOrigin) {
// Finish reflowing child frames, positioning their origins.
PositionRowChildFrames(dx, aDesiredSize.BlockStartAscent() - voffset);
}
return NS_OK;
}
/* virtual */ nsresult
nsMathMLmencloseFrame::PlaceInternal(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize,
bool aWidthOnly)
{
///////////////
// Measure the size of our content using the base class to format like an
// inferred mrow.
ReflowOutput baseSize(aDesiredSize.GetWritingMode());
nsresult rv =
nsMathMLContainerFrame::Place(aDrawTarget, false, baseSize);
if (NS_MATHML_HAS_ERROR(mPresentationData.flags) || NS_FAILED(rv)) {
DidReflowChildren(PrincipalChildList().FirstChild());
return rv;
}
nsBoundingMetrics bmBase = baseSize.mBoundingMetrics;
nscoord dx_left = 0, dx_right = 0;
nsBoundingMetrics bmLongdivChar, bmRadicalChar;
nscoord radicalAscent = 0, radicalDescent = 0;
nscoord longdivAscent = 0, longdivDescent = 0;
nscoord psi = 0;
nscoord leading = 0;
///////////////
// Thickness of bars and font metrics
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetFontMetricsForFrame(this, fontSizeInflation);
GetRuleThickness(aDrawTarget, fm, mRuleThickness);
if (mRuleThickness < onePixel) {
mRuleThickness = onePixel;
}
char16_t one = '1';
nsBoundingMetrics bmOne =
nsLayoutUtils::AppUnitBoundsOfString(&one, 1, *fm, aDrawTarget);
///////////////
// General rules: the menclose element takes the size of the enclosed content.
// We add a padding when needed.
// determine padding & psi
nscoord padding = 3 * mRuleThickness;
nscoord delta = padding % onePixel;
if (delta)
padding += onePixel - delta; // round up
if (IsToDraw(NOTATION_LONGDIV) || IsToDraw(NOTATION_RADICAL)) {
GetRadicalParameters(fm, StyleFont()->mMathDisplay ==
NS_MATHML_DISPLAYSTYLE_BLOCK,
mRadicalRuleThickness, leading, psi);
// make sure that the rule appears on on screen
if (mRadicalRuleThickness < onePixel) {
mRadicalRuleThickness = onePixel;
}
// adjust clearance psi to get an exact number of pixels -- this
// gives a nicer & uniform look on stacked radicals (bug 130282)
delta = psi % onePixel;
if (delta) {
psi += onePixel - delta; // round up
}
}
// Set horizontal parameters
if (IsToDraw(NOTATION_ROUNDEDBOX) ||
IsToDraw(NOTATION_TOP) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_BOTTOM) ||
IsToDraw(NOTATION_CIRCLE))
dx_left = padding;
if (IsToDraw(NOTATION_ROUNDEDBOX) ||
IsToDraw(NOTATION_TOP) ||
IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_BOTTOM) ||
IsToDraw(NOTATION_CIRCLE))
dx_right = padding;
// Set vertical parameters
if (IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_UPDIAGONALSTRIKE) ||
IsToDraw(NOTATION_UPDIAGONALARROW) ||
IsToDraw(NOTATION_DOWNDIAGONALSTRIKE) ||
IsToDraw(NOTATION_VERTICALSTRIKE) ||
IsToDraw(NOTATION_CIRCLE) ||
IsToDraw(NOTATION_ROUNDEDBOX) ||
IsToDraw(NOTATION_RADICAL) ||
IsToDraw(NOTATION_LONGDIV) ||
IsToDraw(NOTATION_PHASORANGLE)) {
// set a minimal value for the base height
bmBase.ascent = std::max(bmOne.ascent, bmBase.ascent);
bmBase.descent = std::max(0, bmBase.descent);
}
mBoundingMetrics.ascent = bmBase.ascent;
mBoundingMetrics.descent = bmBase.descent;
if (IsToDraw(NOTATION_ROUNDEDBOX) ||
IsToDraw(NOTATION_TOP) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_CIRCLE))
mBoundingMetrics.ascent += padding;
if (IsToDraw(NOTATION_ROUNDEDBOX) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_BOTTOM) ||
IsToDraw(NOTATION_CIRCLE))
mBoundingMetrics.descent += padding;
///////////////
// phasorangle notation
if (IsToDraw(NOTATION_PHASORANGLE)) {
nscoord phasorangleWidth = kPhasorangleWidth * mRuleThickness;
// Update horizontal parameters
dx_left = std::max(dx_left, phasorangleWidth);
}
///////////////
// updiagonal arrow notation. We need enough space at the top right corner to
// draw the arrow head.
if (IsToDraw(NOTATION_UPDIAGONALARROW)) {
// This is an estimate, see nsDisplayNotation::Paint for the exact head size
nscoord arrowHeadSize = kArrowHeadSize * mRuleThickness;
// We want that the arrow shaft strikes the menclose content and that the
// arrow head does not overlap with that content. Hence we add some space
// on the right. We don't add space on the top but only ensure that the
// ascent is large enough.
dx_right = std::max(dx_right, arrowHeadSize);
mBoundingMetrics.ascent = std::max(mBoundingMetrics.ascent, arrowHeadSize);
}
///////////////
// circle notation: we don't want the ellipse to overlap the enclosed
// content. Hence, we need to increase the size of the bounding box by a
// factor of at least sqrt(2).
if (IsToDraw(NOTATION_CIRCLE)) {
double ratio = (sqrt(2.0) - 1.0) / 2.0;
nscoord padding2;
// Update horizontal parameters
padding2 = ratio * bmBase.width;
dx_left = std::max(dx_left, padding2);
dx_right = std::max(dx_right, padding2);
// Update vertical parameters
padding2 = ratio * (bmBase.ascent + bmBase.descent);
mBoundingMetrics.ascent = std::max(mBoundingMetrics.ascent,
bmBase.ascent + padding2);
mBoundingMetrics.descent = std::max(mBoundingMetrics.descent,
bmBase.descent + padding2);
}
///////////////
// longdiv notation:
if (IsToDraw(NOTATION_LONGDIV)) {
if (aWidthOnly) {
nscoord longdiv_width = mMathMLChar[mLongDivCharIndex].
GetMaxWidth(PresContext(), aDrawTarget, fontSizeInflation);
// Update horizontal parameters
dx_left = std::max(dx_left, longdiv_width);
} else {
// Stretch the parenthesis to the appropriate height if it is not
// big enough.
nsBoundingMetrics contSize = bmBase;
contSize.ascent = mRuleThickness;
contSize.descent = bmBase.ascent + bmBase.descent + psi;
// height(longdiv) should be >= height(base) + psi + mRuleThickness
mMathMLChar[mLongDivCharIndex].Stretch(PresContext(), aDrawTarget,
fontSizeInflation,
NS_STRETCH_DIRECTION_VERTICAL,
contSize, bmLongdivChar,
NS_STRETCH_LARGER, false);
mMathMLChar[mLongDivCharIndex].GetBoundingMetrics(bmLongdivChar);
// Update horizontal parameters
dx_left = std::max(dx_left, bmLongdivChar.width);
// Update vertical parameters
longdivAscent = bmBase.ascent + psi + mRuleThickness;
longdivDescent = std::max(bmBase.descent,
(bmLongdivChar.ascent + bmLongdivChar.descent -
longdivAscent));
mBoundingMetrics.ascent = std::max(mBoundingMetrics.ascent,
longdivAscent);
mBoundingMetrics.descent = std::max(mBoundingMetrics.descent,
longdivDescent);
}
}
///////////////
// radical notation:
if (IsToDraw(NOTATION_RADICAL)) {
nscoord *dx_leading = StyleVisibility()->mDirection ? &dx_right : &dx_left;
if (aWidthOnly) {
nscoord radical_width = mMathMLChar[mRadicalCharIndex].
GetMaxWidth(PresContext(), aDrawTarget, fontSizeInflation);
// Update horizontal parameters
*dx_leading = std::max(*dx_leading, radical_width);
} else {
// Stretch the radical symbol to the appropriate height if it is not
// big enough.
nsBoundingMetrics contSize = bmBase;
contSize.ascent = mRadicalRuleThickness;
contSize.descent = bmBase.ascent + bmBase.descent + psi;
// height(radical) should be >= height(base) + psi + mRadicalRuleThickness
mMathMLChar[mRadicalCharIndex].Stretch(PresContext(), aDrawTarget,
fontSizeInflation,
NS_STRETCH_DIRECTION_VERTICAL,
contSize, bmRadicalChar,
NS_STRETCH_LARGER,
StyleVisibility()->mDirection);
mMathMLChar[mRadicalCharIndex].GetBoundingMetrics(bmRadicalChar);
// Update horizontal parameters
*dx_leading = std::max(*dx_leading, bmRadicalChar.width);
// Update vertical parameters
radicalAscent = bmBase.ascent + psi + mRadicalRuleThickness;
radicalDescent = std::max(bmBase.descent,
(bmRadicalChar.ascent + bmRadicalChar.descent -
radicalAscent));
mBoundingMetrics.ascent = std::max(mBoundingMetrics.ascent,
radicalAscent);
mBoundingMetrics.descent = std::max(mBoundingMetrics.descent,
radicalDescent);
}
}
///////////////
//
if (IsToDraw(NOTATION_CIRCLE) ||
IsToDraw(NOTATION_ROUNDEDBOX) ||
(IsToDraw(NOTATION_LEFT) && IsToDraw(NOTATION_RIGHT))) {
// center the menclose around the content (horizontally)
dx_left = dx_right = std::max(dx_left, dx_right);
}
///////////////
// The maximum size is now computed: set the remaining parameters
mBoundingMetrics.width = dx_left + bmBase.width + dx_right;
mBoundingMetrics.leftBearing = std::min(0, dx_left + bmBase.leftBearing);
mBoundingMetrics.rightBearing =
std::max(mBoundingMetrics.width, dx_left + bmBase.rightBearing);
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.SetBlockStartAscent(std::max(mBoundingMetrics.ascent,
baseSize.BlockStartAscent()));
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
std::max(mBoundingMetrics.descent,
baseSize.Height() - baseSize.BlockStartAscent());
if (IsToDraw(NOTATION_LONGDIV) || IsToDraw(NOTATION_RADICAL)) {
nscoord desiredSizeAscent = aDesiredSize.BlockStartAscent();
nscoord desiredSizeDescent = aDesiredSize.Height() -
aDesiredSize.BlockStartAscent();
if (IsToDraw(NOTATION_LONGDIV)) {
desiredSizeAscent = std::max(desiredSizeAscent,
longdivAscent + leading);
desiredSizeDescent = std::max(desiredSizeDescent,
longdivDescent + mRuleThickness);
}
if (IsToDraw(NOTATION_RADICAL)) {
desiredSizeAscent = std::max(desiredSizeAscent,
radicalAscent + leading);
desiredSizeDescent = std::max(desiredSizeDescent,
radicalDescent + mRadicalRuleThickness);
}
aDesiredSize.SetBlockStartAscent(desiredSizeAscent);
aDesiredSize.Height() = desiredSizeAscent + desiredSizeDescent;
}
if (IsToDraw(NOTATION_CIRCLE) ||
IsToDraw(NOTATION_ROUNDEDBOX) ||
(IsToDraw(NOTATION_TOP) && IsToDraw(NOTATION_BOTTOM))) {
// center the menclose around the content (vertically)
nscoord dy = std::max(aDesiredSize.BlockStartAscent() - bmBase.ascent,
aDesiredSize.Height() -
aDesiredSize.BlockStartAscent() - bmBase.descent);
aDesiredSize.SetBlockStartAscent(bmBase.ascent + dy);
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() + bmBase.descent + dy;
}
// Update mBoundingMetrics ascent/descent
if (IsToDraw(NOTATION_TOP) ||
IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_UPDIAGONALSTRIKE) ||
IsToDraw(NOTATION_UPDIAGONALARROW) ||
IsToDraw(NOTATION_DOWNDIAGONALSTRIKE) ||
IsToDraw(NOTATION_VERTICALSTRIKE) ||
IsToDraw(NOTATION_CIRCLE) ||
IsToDraw(NOTATION_ROUNDEDBOX))
mBoundingMetrics.ascent = aDesiredSize.BlockStartAscent();
if (IsToDraw(NOTATION_BOTTOM) ||
IsToDraw(NOTATION_RIGHT) ||
IsToDraw(NOTATION_LEFT) ||
IsToDraw(NOTATION_UPDIAGONALSTRIKE) ||
IsToDraw(NOTATION_UPDIAGONALARROW) ||
IsToDraw(NOTATION_DOWNDIAGONALSTRIKE) ||
IsToDraw(NOTATION_VERTICALSTRIKE) ||
IsToDraw(NOTATION_CIRCLE) ||
IsToDraw(NOTATION_ROUNDEDBOX))
mBoundingMetrics.descent = aDesiredSize.Height() - aDesiredSize.BlockStartAscent();
// phasorangle notation:
// move up from the bottom by the angled line height
if (IsToDraw(NOTATION_PHASORANGLE))
mBoundingMetrics.ascent = std::max(mBoundingMetrics.ascent, 2 * kPhasorangleWidth * mRuleThickness - mBoundingMetrics.descent);
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
if (aPlaceOrigin) {
//////////////////
// Set position and size of MathMLChars
if (IsToDraw(NOTATION_LONGDIV))
mMathMLChar[mLongDivCharIndex].SetRect(nsRect(dx_left -
bmLongdivChar.width,
aDesiredSize.BlockStartAscent() -
longdivAscent,
bmLongdivChar.width,
bmLongdivChar.ascent +
bmLongdivChar.descent));
if (IsToDraw(NOTATION_RADICAL)) {
nscoord dx = (StyleVisibility()->mDirection ?
dx_left + bmBase.width : dx_left - bmRadicalChar.width);
mMathMLChar[mRadicalCharIndex].SetRect(nsRect(dx,
aDesiredSize.BlockStartAscent() -
radicalAscent,
bmRadicalChar.width,
bmRadicalChar.ascent +
bmRadicalChar.descent));
}
mContentWidth = bmBase.width;
//////////////////
// Finish reflowing child frames
PositionRowChildFrames(dx_left, aDesiredSize.BlockStartAscent());
}
return NS_OK;
}
void
BRFrame::Reflow(nsPresContext* aPresContext,
ReflowOutput& aMetrics,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus)
{
MarkInReflow();
DO_GLOBAL_REFLOW_COUNT("BRFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowInput, aMetrics, aStatus);
WritingMode wm = aReflowInput.GetWritingMode();
LogicalSize finalSize(wm);
finalSize.BSize(wm) = 0; // BR frames with block size 0 are ignored in quirks
// mode by nsLineLayout::VerticalAlignFrames .
// However, it's not always 0. See below.
finalSize.ISize(wm) = 0;
aMetrics.SetBlockStartAscent(0);
// Only when the BR is operating in a line-layout situation will it
// behave like a BR. Additionally, we suppress breaks from BR inside
// of ruby frames. To determine if we're inside ruby, we have to rely
// on the *parent's* ShouldSuppressLineBreak() method, instead of our
// own, because we may have custom "display" value that makes our
// ShouldSuppressLineBreak() return false.
nsLineLayout* ll = aReflowInput.mLineLayout;
if (ll && !GetParent()->StyleContext()->ShouldSuppressLineBreak()) {
// Note that the compatibility mode check excludes AlmostStandards
// mode, since this is the inline box model. See bug 161691.
if ( ll->LineIsEmpty() ||
aPresContext->CompatibilityMode() == eCompatibility_FullStandards ) {
// The line is logically empty; any whitespace is trimmed away.
//
// If this frame is going to terminate the line we know
// that nothing else will go on the line. Therefore, in this
// case, we provide some height for the BR frame so that it
// creates some vertical whitespace. It's necessary to use the
// line-height rather than the font size because the
// quirks-mode fix that doesn't apply the block's min
// line-height makes this necessary to make BR cause a line
// of the full line-height
// We also do this in strict mode because BR should act like a
// normal inline frame. That line-height is used is important
// here for cases where the line-height is less than 1.
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetInflatedFontMetricsForFrame(this);
if (fm) {
nscoord logicalHeight = aReflowInput.CalcLineHeight();
finalSize.BSize(wm) = logicalHeight;
aMetrics.SetBlockStartAscent(nsLayoutUtils::GetCenteredFontBaseline(
fm, logicalHeight, wm.IsLineInverted()));
}
else {
aMetrics.SetBlockStartAscent(aMetrics.BSize(wm) = 0);
}
// XXX temporary until I figure out a better solution; see the
// code in nsLineLayout::VerticalAlignFrames that zaps minY/maxY
// if the width is zero.
// XXX This also fixes bug 10036!
// Warning: nsTextControlFrame::CalculateSizeStandard depends on
// the following line, see bug 228752.
// The code below in AddInlinePrefISize also adds 1 appunit to width
finalSize.ISize(wm) = 1;
}
// Return our reflow status
uint32_t breakType = aReflowInput.mStyleDisplay->PhysicalBreakType(wm);
if (NS_STYLE_CLEAR_NONE == breakType) {
breakType = NS_STYLE_CLEAR_LINE;
}
aStatus = NS_INLINE_BREAK | NS_INLINE_BREAK_AFTER |
NS_INLINE_MAKE_BREAK_TYPE(breakType);
ll->SetLineEndsInBR(true);
}
else {
aStatus = NS_FRAME_COMPLETE;
}
aMetrics.SetSize(wm, finalSize);
aMetrics.SetOverflowAreasToDesiredBounds();
mAscent = aMetrics.BlockStartAscent();
NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aMetrics);
}
void
nsMathMLmrootFrame::Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus)
{
MarkInReflow();
nsReflowStatus childStatus;
mPresentationData.flags &= ~NS_MATHML_ERROR;
aDesiredSize.ClearSize();
aDesiredSize.SetBlockStartAscent(0);
nsBoundingMetrics bmSqr, bmBase, bmIndex;
DrawTarget* drawTarget = aReflowInput.mRenderingContext->GetDrawTarget();
//////////////////
// Reflow Children
int32_t count = 0;
nsIFrame* baseFrame = nullptr;
nsIFrame* indexFrame = nullptr;
ReflowOutput baseSize(aReflowInput);
ReflowOutput indexSize(aReflowInput);
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
// ask our children to compute their bounding metrics
ReflowOutput childDesiredSize(aReflowInput,
aDesiredSize.mFlags
| NS_REFLOW_CALC_BOUNDING_METRICS);
WritingMode wm = childFrame->GetWritingMode();
LogicalSize availSize = aReflowInput.ComputedSize(wm);
availSize.BSize(wm) = NS_UNCONSTRAINEDSIZE;
ReflowInput childReflowInput(aPresContext, aReflowInput,
childFrame, availSize);
ReflowChild(childFrame, aPresContext,
childDesiredSize, childReflowInput, childStatus);
//NS_ASSERTION(childStatus.IsComplete(), "bad status");
if (0 == count) {
// base
baseFrame = childFrame;
baseSize = childDesiredSize;
bmBase = childDesiredSize.mBoundingMetrics;
}
else if (1 == count) {
// index
indexFrame = childFrame;
indexSize = childDesiredSize;
bmIndex = childDesiredSize.mBoundingMetrics;
}
count++;
childFrame = childFrame->GetNextSibling();
}
if (2 != count) {
// report an error, encourage people to get their markups in order
ReportChildCountError();
ReflowError(drawTarget, aDesiredSize);
aStatus.Reset();
NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
// Call DidReflow() for the child frames we successfully did reflow.
DidReflowChildren(mFrames.FirstChild(), childFrame);
return;
}
////////////
// Prepare the radical symbol and the overline bar
float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetFontMetricsForFrame(this, fontSizeInflation);
nscoord ruleThickness, leading, psi;
GetRadicalParameters(fm, StyleFont()->mMathDisplay ==
NS_MATHML_DISPLAYSTYLE_BLOCK,
ruleThickness, leading, psi);
// built-in: adjust clearance psi to emulate \mathstrut using '1' (TexBook, p.131)
char16_t one = '1';
nsBoundingMetrics bmOne =
nsLayoutUtils::AppUnitBoundsOfString(&one, 1, *fm, drawTarget);
if (bmOne.ascent > bmBase.ascent)
psi += bmOne.ascent - bmBase.ascent;
// make sure that the rule appears on on screen
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
if (ruleThickness < onePixel) {
ruleThickness = onePixel;
}
// adjust clearance psi to get an exact number of pixels -- this
// gives a nicer & uniform look on stacked radicals (bug 130282)
nscoord delta = psi % onePixel;
if (delta)
psi += onePixel - delta; // round up
// Stretch the radical symbol to the appropriate height if it is not big enough.
nsBoundingMetrics contSize = bmBase;
contSize.descent = bmBase.ascent + bmBase.descent + psi;
contSize.ascent = ruleThickness;
// height(radical) should be >= height(base) + psi + ruleThickness
nsBoundingMetrics radicalSize;
mSqrChar.Stretch(aPresContext, drawTarget,
fontSizeInflation,
NS_STRETCH_DIRECTION_VERTICAL,
contSize, radicalSize,
NS_STRETCH_LARGER,
StyleVisibility()->mDirection);
// radicalSize have changed at this point, and should match with
// the bounding metrics of the char
mSqrChar.GetBoundingMetrics(bmSqr);
// Update the desired size for the container (like msqrt, index is not yet included)
// the baseline will be that of the base.
mBoundingMetrics.ascent = bmBase.ascent + psi + ruleThickness;
mBoundingMetrics.descent =
std::max(bmBase.descent,
(bmSqr.ascent + bmSqr.descent - mBoundingMetrics.ascent));
mBoundingMetrics.width = bmSqr.width + bmBase.width;
mBoundingMetrics.leftBearing = bmSqr.leftBearing;
mBoundingMetrics.rightBearing = bmSqr.width +
std::max(bmBase.width, bmBase.rightBearing); // take also care of the rule
aDesiredSize.SetBlockStartAscent(mBoundingMetrics.ascent + leading);
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
std::max(baseSize.Height() - baseSize.BlockStartAscent(),
mBoundingMetrics.descent + ruleThickness);
aDesiredSize.Width() = mBoundingMetrics.width;
/////////////
// Re-adjust the desired size to include the index.
// the index is raised by some fraction of the height
// of the radical, see \mroot macro in App. B, TexBook
float raiseIndexPercent = 0.6f;
gfxFont* mathFont = fm->GetThebesFontGroup()->GetFirstMathFont();
if (mathFont) {
raiseIndexPercent = mathFont->MathTable()->
Constant(gfxMathTable::RadicalDegreeBottomRaisePercent);
}
nscoord raiseIndexDelta = NSToCoordRound(raiseIndexPercent *
(bmSqr.ascent + bmSqr.descent));
nscoord indexRaisedAscent = mBoundingMetrics.ascent // top of radical
- (bmSqr.ascent + bmSqr.descent) // to bottom of radical
+ raiseIndexDelta + bmIndex.ascent + bmIndex.descent; // to top of raised index
nscoord indexClearance = 0;
if (mBoundingMetrics.ascent < indexRaisedAscent) {
indexClearance =
indexRaisedAscent - mBoundingMetrics.ascent; // excess gap introduced by a tall index
mBoundingMetrics.ascent = indexRaisedAscent;
nscoord descent = aDesiredSize.Height() - aDesiredSize.BlockStartAscent();
aDesiredSize.SetBlockStartAscent(mBoundingMetrics.ascent + leading);
aDesiredSize.Height() = aDesiredSize.BlockStartAscent() + descent;
}
nscoord dxIndex, dxSqr;
GetRadicalXOffsets(bmIndex.width, bmSqr.width, fm, &dxIndex, &dxSqr);
mBoundingMetrics.width = dxSqr + bmSqr.width + bmBase.width;
mBoundingMetrics.leftBearing =
std::min(dxIndex + bmIndex.leftBearing, dxSqr + bmSqr.leftBearing);
mBoundingMetrics.rightBearing = dxSqr + bmSqr.width +
std::max(bmBase.width, bmBase.rightBearing);
aDesiredSize.Width() = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
GatherAndStoreOverflow(&aDesiredSize);
// place the index
nscoord dx = dxIndex;
nscoord dy = aDesiredSize.BlockStartAscent() -
(indexRaisedAscent + indexSize.BlockStartAscent() - bmIndex.ascent);
FinishReflowChild(indexFrame, aPresContext, indexSize, nullptr,
MirrorIfRTL(aDesiredSize.Width(), indexSize.Width(), dx),
dy, 0);
// place the radical symbol and the radical bar
dx = dxSqr;
dy = indexClearance + leading; // leave a leading at the top
mSqrChar.SetRect(nsRect(MirrorIfRTL(aDesiredSize.Width(), bmSqr.width, dx),
dy, bmSqr.width, bmSqr.ascent + bmSqr.descent));
dx += bmSqr.width;
mBarRect.SetRect(MirrorIfRTL(aDesiredSize.Width(), bmBase.width, dx),
dy, bmBase.width, ruleThickness);
// place the base
dy = aDesiredSize.BlockStartAscent() - baseSize.BlockStartAscent();
FinishReflowChild(baseFrame, aPresContext, baseSize, nullptr,
MirrorIfRTL(aDesiredSize.Width(), baseSize.Width(), dx),
dy, 0);
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
aStatus.Reset();
NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
}
/* 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;
}
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;
}