/* static */ void
nsMathMLFrame::GetAxisHeight(nsIRenderingContext& aRenderingContext,
nsIFontMetrics* aFontMetrics,
nscoord& aAxisHeight)
{
// get the bounding metrics of the minus sign, the rendering context
// is assumed to have been set with the font of the current style context
#ifdef NS_DEBUG
nsCOMPtr<nsIFontMetrics> currFontMetrics;
aRenderingContext.GetFontMetrics(*getter_AddRefs(currFontMetrics));
NS_ASSERTION(currFontMetrics->Font().Equals(aFontMetrics->Font()),
"unexpected state");
#endif
nscoord xHeight;
aFontMetrics->GetXHeight(xHeight);
PRUnichar minus = 0x2212; // not '-', but official Unicode minus sign
nsBoundingMetrics bm;
nsresult rv = aRenderingContext.GetBoundingMetrics(&minus, PRUint32(1), bm);
if (NS_SUCCEEDED(rv)) {
aAxisHeight = bm.ascent - (bm.ascent + bm.descent)/2;
}
if (NS_FAILED(rv) || aAxisHeight <= 0 || aAxisHeight >= xHeight) {
// fall-back to the other version
GetAxisHeight(aFontMetrics, aAxisHeight);
}
}
/* static */ void
nsMathMLFrame::GetAxisHeight(nsRenderingContext& aRenderingContext,
nsFontMetrics* aFontMetrics,
nscoord& aAxisHeight)
{
// get the bounding metrics of the minus sign, the rendering context
// is assumed to have been set with the font of the current style context
NS_ASSERTION(aRenderingContext.FontMetrics()->Font().
Equals(aFontMetrics->Font()),
"unexpected state");
nscoord xHeight = aFontMetrics->XHeight();
PRUnichar minus = 0x2212; // not '-', but official Unicode minus sign
nsBoundingMetrics bm = aRenderingContext.GetBoundingMetrics(&minus, 1);
aAxisHeight = bm.ascent - (bm.ascent + bm.descent)/2;
if (aAxisHeight <= 0 || aAxisHeight >= xHeight) {
// fall-back to the other version
GetAxisHeight(aFontMetrics, aAxisHeight);
}
}
NS_IMETHODIMP
nsMathMLmfencedFrame::Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
nsresult rv;
aDesiredSize.width = aDesiredSize.height = 0;
aDesiredSize.ascent = 0;
aDesiredSize.mBoundingMetrics = nsBoundingMetrics();
PRInt32 i;
const nsStyleFont* font = GetStyleFont();
nsRefPtr<nsFontMetrics> fm;
nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm));
aReflowState.rendContext->SetFont(fm);
nscoord axisHeight, em;
GetAxisHeight(*aReflowState.rendContext, fm, axisHeight);
GetEmHeight(fm, em);
// leading to be left at the top and the bottom of stretched chars
nscoord leading = NSToCoordRound(0.2f * em);
/////////////
// Reflow children
// Asking each child to cache its bounding metrics
// Note that we don't use the base method nsMathMLContainerFrame::Reflow()
// because we want to stretch our fences, separators and stretchy frames using
// the *same* initial aDesiredSize.mBoundingMetrics. If we were to use the base
// method here, our stretchy frames will be stretched and placed, and we may
// end up stretching our fences/separators with a different aDesiredSize.
// XXX The above decision was revisited in bug 121748 and this code can be
// refactored to use nsMathMLContainerFrame::Reflow() at some stage.
nsReflowStatus childStatus;
nsSize availSize(aReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE);
nsIFrame* firstChild = GetFirstChild(nsnull);
nsIFrame* childFrame = firstChild;
nscoord ascent = 0, descent = 0;
if (firstChild || mOpenChar || mCloseChar || mSeparatorsCount > 0) {
// We use the ASCII metrics to get our minimum height. This way,
// if we have borders or a background, they will fit better with
// other elements on the line.
ascent = fm->MaxAscent();
descent = fm->MaxDescent();
}
while (childFrame) {
nsHTMLReflowMetrics childDesiredSize(aDesiredSize.mFlags
| NS_REFLOW_CALC_BOUNDING_METRICS);
nsHTMLReflowState childReflowState(aPresContext, aReflowState,
childFrame, availSize);
rv = ReflowChild(childFrame, aPresContext, childDesiredSize,
childReflowState, childStatus);
//NS_ASSERTION(NS_FRAME_IS_COMPLETE(childStatus), "bad status");
if (NS_FAILED(rv)) {
// Call DidReflow() for the child frames we successfully did reflow.
DidReflowChildren(firstChild, childFrame);
return rv;
}
SaveReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
nscoord childDescent = childDesiredSize.height - childDesiredSize.ascent;
if (descent < childDescent)
descent = childDescent;
if (ascent < childDesiredSize.ascent)
ascent = childDesiredSize.ascent;
childFrame = childFrame->GetNextSibling();
}
/////////////
// Ask stretchy children to stretch themselves
nsBoundingMetrics containerSize;
nsStretchDirection stretchDir = NS_STRETCH_DIRECTION_VERTICAL;
GetPreferredStretchSize(*aReflowState.rendContext,
0, /* i.e., without embellishments */
stretchDir, containerSize);
childFrame = firstChild;
while (childFrame) {
nsIMathMLFrame* mathmlChild = do_QueryFrame(childFrame);
if (mathmlChild) {
nsHTMLReflowMetrics childDesiredSize;
// retrieve the metrics that was stored at the previous pass
GetReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
mathmlChild->Stretch(*aReflowState.rendContext,
stretchDir, containerSize, childDesiredSize);
// store the updated metrics
SaveReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
nscoord childDescent = childDesiredSize.height - childDesiredSize.ascent;
if (descent < childDescent)
descent = childDescent;
if (ascent < childDesiredSize.ascent)
ascent = childDesiredSize.ascent;
}
childFrame = childFrame->GetNextSibling();
}
// bug 121748: for surrounding fences & separators, use a size that covers everything
GetPreferredStretchSize(*aReflowState.rendContext,
STRETCH_CONSIDER_EMBELLISHMENTS,
stretchDir, containerSize);
//////////////////////////////////////////
// Prepare the opening fence, separators, and closing fence, and
// adjust the origin of children.
// we need to center around the axis
nscoord delta = NS_MAX(containerSize.ascent - axisHeight,
containerSize.descent + axisHeight);
containerSize.ascent = delta + axisHeight;
containerSize.descent = delta - axisHeight;
/////////////////
// opening fence ...
ReflowChar(aPresContext, *aReflowState.rendContext, mOpenChar,
NS_MATHML_OPERATOR_FORM_PREFIX, font->mScriptLevel,
axisHeight, leading, em, containerSize, ascent, descent);
/////////////////
// separators ...
for (i = 0; i < mSeparatorsCount; i++) {
ReflowChar(aPresContext, *aReflowState.rendContext, &mSeparatorsChar[i],
NS_MATHML_OPERATOR_FORM_INFIX, font->mScriptLevel,
axisHeight, leading, em, containerSize, ascent, descent);
}
/////////////////
// closing fence ...
ReflowChar(aPresContext, *aReflowState.rendContext, mCloseChar,
NS_MATHML_OPERATOR_FORM_POSTFIX, font->mScriptLevel,
axisHeight, leading, em, containerSize, ascent, descent);
//////////////////
// Adjust the origins of each child.
// and update our bounding metrics
i = 0;
nscoord dx = 0;
nsBoundingMetrics bm;
PRBool firstTime = PR_TRUE;
if (mOpenChar) {
PlaceChar(mOpenChar, ascent, bm, dx);
aDesiredSize.mBoundingMetrics = bm;
firstTime = PR_FALSE;
}
childFrame = firstChild;
while (childFrame) {
nsHTMLReflowMetrics childSize;
GetReflowAndBoundingMetricsFor(childFrame, childSize, bm);
if (firstTime) {
firstTime = PR_FALSE;
aDesiredSize.mBoundingMetrics = bm;
}
else
aDesiredSize.mBoundingMetrics += bm;
FinishReflowChild(childFrame, aPresContext, nsnull, childSize,
dx, ascent - childSize.ascent, 0);
dx += childSize.width;
if (i < mSeparatorsCount) {
PlaceChar(&mSeparatorsChar[i], ascent, bm, dx);
aDesiredSize.mBoundingMetrics += bm;
}
i++;
childFrame = childFrame->GetNextSibling();
}
if (mCloseChar) {
PlaceChar(mCloseChar, ascent, bm, dx);
if (firstTime)
aDesiredSize.mBoundingMetrics = bm;
else
aDesiredSize.mBoundingMetrics += bm;
}
aDesiredSize.width = aDesiredSize.mBoundingMetrics.width;
aDesiredSize.height = ascent + descent;
aDesiredSize.ascent = ascent;
SetBoundingMetrics(aDesiredSize.mBoundingMetrics);
SetReference(nsPoint(0, aDesiredSize.ascent));
// see if we should fix the spacing
FixInterFrameSpacing(aDesiredSize);
// Finished with these:
ClearSavedChildMetrics();
// Set our overflow area
GatherAndStoreOverflow(&aDesiredSize);
aStatus = NS_FRAME_COMPLETE;
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
return NS_OK;
}
// NOTE: aDesiredStretchSize is an IN/OUT parameter
// On input - it contains our current size
// On output - the same size or the new size that we want
NS_IMETHODIMP
nsMathMLmoFrame::Stretch(nsRenderingContext& aRenderingContext,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aContainerSize,
nsHTMLReflowMetrics& aDesiredStretchSize)
{
if (NS_MATHML_STRETCH_WAS_DONE(mPresentationData.flags)) {
NS_WARNING("it is wrong to fire stretch more than once on a frame");
return NS_OK;
}
mPresentationData.flags |= NS_MATHML_STRETCH_DONE;
nsIFrame* firstChild = mFrames.FirstChild();
// get the axis height;
nsRefPtr<nsFontMetrics> fm;
nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm));
aRenderingContext.SetFont(fm);
nscoord axisHeight, height;
GetAxisHeight(aRenderingContext, fm, axisHeight);
// get the leading to be left at the top and the bottom of the stretched char
// this seems more reliable than using fm->GetLeading() on suspicious fonts
nscoord em;
GetEmHeight(fm, em);
nscoord leading = NSToCoordRound(0.2f * em);
// Operators that are stretchy, or those that are to be centered
// to cater for fonts that are not math-aware, are handled by the MathMLChar
// ('form' is reset if stretch fails -- i.e., we don't bother to stretch next time)
bool useMathMLChar = UseMathMLChar();
nsBoundingMetrics charSize;
nsBoundingMetrics container = aDesiredStretchSize.mBoundingMetrics;
bool isVertical = false;
if (((aStretchDirection == NS_STRETCH_DIRECTION_VERTICAL) ||
(aStretchDirection == NS_STRETCH_DIRECTION_DEFAULT)) &&
(mEmbellishData.direction == NS_STRETCH_DIRECTION_VERTICAL)) {
isVertical = true;
}
uint32_t stretchHint =
GetStretchHint(mFlags, mPresentationData, isVertical);
if (useMathMLChar) {
nsBoundingMetrics initialSize = aDesiredStretchSize.mBoundingMetrics;
if (stretchHint != NS_STRETCH_NONE) {
container = aContainerSize;
// some adjustments if the operator is symmetric and vertical
if (isVertical && NS_MATHML_OPERATOR_IS_SYMMETRIC(mFlags)) {
// we need to center about the axis
nscoord delta = std::max(container.ascent - axisHeight,
container.descent + axisHeight);
container.ascent = delta + axisHeight;
container.descent = delta - axisHeight;
// get ready in case we encounter user-desired min-max size
delta = std::max(initialSize.ascent - axisHeight,
initialSize.descent + axisHeight);
initialSize.ascent = delta + axisHeight;
initialSize.descent = delta - axisHeight;
}
// check for user-desired min-max size
if (mMaxSize != NS_MATHML_OPERATOR_SIZE_INFINITY && mMaxSize > 0.0f) {
// if we are here, there is a user defined maxsize ...
//XXX Set stretchHint = NS_STRETCH_NORMAL? to honor the maxsize as close as possible?
if (NS_MATHML_OPERATOR_MAXSIZE_IS_ABSOLUTE(mFlags)) {
// there is an explicit value like maxsize="20pt"
// try to maintain the aspect ratio of the char
float aspect = mMaxSize / float(initialSize.ascent + initialSize.descent);
container.ascent =
std::min(container.ascent, nscoord(initialSize.ascent * aspect));
container.descent =
std::min(container.descent, nscoord(initialSize.descent * aspect));
// below we use a type cast instead of a conversion to avoid a VC++ bug
// see http://support.microsoft.com/support/kb/articles/Q115/7/05.ASP
container.width =
std::min(container.width, (nscoord)mMaxSize);
}
else { // multiplicative value
container.ascent =
std::min(container.ascent, nscoord(initialSize.ascent * mMaxSize));
container.descent =
std::min(container.descent, nscoord(initialSize.descent * mMaxSize));
container.width =
std::min(container.width, nscoord(initialSize.width * mMaxSize));
}
if (isVertical && !NS_MATHML_OPERATOR_IS_SYMMETRIC(mFlags)) {
// re-adjust to align the char with the bottom of the initial container
height = container.ascent + container.descent;
container.descent = aContainerSize.descent;
container.ascent = height - container.descent;
}
}
if (mMinSize > 0.0f) {
// if we are here, there is a user defined minsize ...
// always allow the char to stretch in its natural direction,
// even if it is different from the caller's direction
if (aStretchDirection != NS_STRETCH_DIRECTION_DEFAULT &&
aStretchDirection != mEmbellishData.direction) {
aStretchDirection = NS_STRETCH_DIRECTION_DEFAULT;
// but when we are not honoring the requested direction
// we should not use the caller's container size either
container = initialSize;
}
if (NS_MATHML_OPERATOR_MINSIZE_IS_ABSOLUTE(mFlags)) {
// there is an explicit value like minsize="20pt"
// try to maintain the aspect ratio of the char
float aspect = mMinSize / float(initialSize.ascent + initialSize.descent);
container.ascent =
std::max(container.ascent, nscoord(initialSize.ascent * aspect));
container.descent =
std::max(container.descent, nscoord(initialSize.descent * aspect));
container.width =
std::max(container.width, (nscoord)mMinSize);
}
else { // multiplicative value
container.ascent =
std::max(container.ascent, nscoord(initialSize.ascent * mMinSize));
container.descent =
std::max(container.descent, nscoord(initialSize.descent * mMinSize));
container.width =
std::max(container.width, nscoord(initialSize.width * mMinSize));
}
if (isVertical && !NS_MATHML_OPERATOR_IS_SYMMETRIC(mFlags)) {
// re-adjust to align the char with the bottom of the initial container
height = container.ascent + container.descent;
container.descent = aContainerSize.descent;
container.ascent = height - container.descent;
}
}
}
// let the MathMLChar stretch itself...
nsresult res = mMathMLChar.Stretch(PresContext(), aRenderingContext,
aStretchDirection, container, charSize,
stretchHint,
StyleVisibility()->mDirection);
if (NS_FAILED(res)) {
// gracefully handle cases where stretching the char failed (i.e., GetBoundingMetrics failed)
// clear our 'form' to behave as if the operator wasn't in the dictionary
mFlags &= ~NS_MATHML_OPERATOR_FORM;
useMathMLChar = false;
}
}
// Child frames of invisble operators are not reflowed
if (!NS_MATHML_OPERATOR_IS_INVISIBLE(mFlags)) {
// Place our children using the default method
// This will allow our child text frame to get its DidReflow()
nsresult rv = Place(aRenderingContext, true, aDesiredStretchSize);
if (NS_MATHML_HAS_ERROR(mPresentationData.flags) || NS_FAILED(rv)) {
// Make sure the child frames get their DidReflow() calls.
DidReflowChildren(mFrames.FirstChild());
}
}
if (useMathMLChar) {
// update our bounding metrics... it becomes that of our MathML char
mBoundingMetrics = charSize;
// if the returned direction is 'unsupported', the char didn't actually change.
// So we do the centering only if necessary
if (mMathMLChar.GetStretchDirection() != NS_STRETCH_DIRECTION_UNSUPPORTED ||
NS_MATHML_OPERATOR_IS_CENTERED(mFlags)) {
bool largeopOnly =
(NS_STRETCH_LARGEOP & stretchHint) != 0 &&
(NS_STRETCH_VARIABLE_MASK & stretchHint) == 0;
if (isVertical || NS_MATHML_OPERATOR_IS_CENTERED(mFlags)) {
// the desired size returned by mMathMLChar maybe different
// from the size of the container.
// the mMathMLChar.mRect.y calculation is subtle, watch out!!!
height = mBoundingMetrics.ascent + mBoundingMetrics.descent;
if (NS_MATHML_OPERATOR_IS_SYMMETRIC(mFlags) ||
NS_MATHML_OPERATOR_IS_CENTERED(mFlags)) {
// For symmetric and vertical operators, or for operators that are always
// centered ('+', '*', etc) we want to center about the axis of the container
mBoundingMetrics.descent = height/2 - axisHeight;
} else if (!largeopOnly) {
// Align the center of the char with the center of the container
mBoundingMetrics.descent = height/2 +
(container.ascent + container.descent)/2 - container.ascent;
} // else align the baselines
mBoundingMetrics.ascent = height - mBoundingMetrics.descent;
}
}
}
// Fixup for the final height.
// On one hand, our stretchy height can sometimes be shorter than surrounding
// ASCII chars, e.g., arrow symbols have |mBoundingMetrics.ascent + leading|
// that is smaller than the ASCII's ascent, hence when painting the background
// later, it won't look uniform along the line.
// On the other hand, sometimes we may leave too much gap when our glyph happens
// to come from a font with tall glyphs. For example, since CMEX10 has very tall
// glyphs, its natural font metrics are large, even if we pick a small glyph
// whose size is comparable to the size of a normal ASCII glyph.
// So to avoid uneven spacing in either of these two cases, we use the height
// of the ASCII font as a reference and try to match it if possible.
// special case for accents... keep them short to improve mouse operations...
// an accent can only be the non-first child of <mover>, <munder>, <munderover>
bool isAccent =
NS_MATHML_EMBELLISH_IS_ACCENT(mEmbellishData.flags);
if (isAccent) {
nsEmbellishData parentData;
GetEmbellishDataFrom(mParent, parentData);
isAccent =
(NS_MATHML_EMBELLISH_IS_ACCENTOVER(parentData.flags) ||
NS_MATHML_EMBELLISH_IS_ACCENTUNDER(parentData.flags)) &&
parentData.coreFrame != this;
}
if (isAccent && firstChild) {
// see bug 188467 for what is going on here
nscoord dy = aDesiredStretchSize.ascent - (mBoundingMetrics.ascent + leading);
aDesiredStretchSize.ascent = mBoundingMetrics.ascent + leading;
aDesiredStretchSize.height = aDesiredStretchSize.ascent + mBoundingMetrics.descent;
firstChild->SetPosition(firstChild->GetPosition() - nsPoint(0, dy));
}
else if (useMathMLChar) {
nscoord ascent = fm->MaxAscent();
nscoord descent = fm->MaxDescent();
aDesiredStretchSize.ascent = std::max(mBoundingMetrics.ascent + leading, ascent);
aDesiredStretchSize.height = aDesiredStretchSize.ascent +
std::max(mBoundingMetrics.descent + leading, descent);
}
aDesiredStretchSize.width = mBoundingMetrics.width;
aDesiredStretchSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredStretchSize.ascent;
// Place our mMathMLChar, its origin is in our coordinate system
if (useMathMLChar) {
nscoord dy = aDesiredStretchSize.ascent - mBoundingMetrics.ascent;
mMathMLChar.SetRect(nsRect(0, dy, charSize.width, charSize.ascent + charSize.descent));
}
// Before we leave... there is a last item in the check-list:
// If our parent is not embellished, it means we are the outermost embellished
// container and so we put the spacing, otherwise we don't include the spacing,
// the outermost embellished container will take care of it.
if (!NS_MATHML_OPERATOR_HAS_EMBELLISH_ANCESTOR(mFlags)) {
// Account the spacing if we are not an accent with explicit attributes
nscoord leadingSpace = mEmbellishData.leadingSpace;
if (isAccent && !NS_MATHML_OPERATOR_HAS_LSPACE_ATTR(mFlags)) {
leadingSpace = 0;
}
nscoord trailingSpace = mEmbellishData.trailingSpace;
if (isAccent && !NS_MATHML_OPERATOR_HAS_RSPACE_ATTR(mFlags)) {
trailingSpace = 0;
}
mBoundingMetrics.width += leadingSpace + trailingSpace;
aDesiredStretchSize.width = mBoundingMetrics.width;
aDesiredStretchSize.mBoundingMetrics.width = mBoundingMetrics.width;
nscoord dx = (StyleVisibility()->mDirection ?
trailingSpace : leadingSpace);
if (dx) {
// adjust the offsets
mBoundingMetrics.leftBearing += dx;
mBoundingMetrics.rightBearing += dx;
aDesiredStretchSize.mBoundingMetrics.leftBearing += dx;
aDesiredStretchSize.mBoundingMetrics.rightBearing += dx;
if (useMathMLChar) {
nsRect rect;
mMathMLChar.GetRect(rect);
mMathMLChar.SetRect(nsRect(rect.x + dx, rect.y,
rect.width, rect.height));
}
else {
nsIFrame* childFrame = firstChild;
while (childFrame) {
childFrame->SetPosition(childFrame->GetPosition() +
nsPoint(dx, 0));
childFrame = childFrame->GetNextSibling();
}
}
}
}
// Finished with these:
ClearSavedChildMetrics();
// Set our overflow area
GatherAndStoreOverflow(&aDesiredStretchSize);
// There used to be code here to change the height of the child frame to
// change the caret height, but the text frame that manages the caret is now
// not a direct child but wrapped in a block frame. See also bug 412033.
return NS_OK;
}
nsresult
nsMathMLmfracFrame::PlaceInternal(nsRenderingContext& aRenderingContext,
bool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize,
bool aWidthOnly)
{
////////////////////////////////////
// Get the children's desired sizes
nsBoundingMetrics bmNum, bmDen;
nsHTMLReflowMetrics sizeNum;
nsHTMLReflowMetrics sizeDen;
nsIFrame* frameDen = nsnull;
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
return ReflowError(aRenderingContext, aDesiredSize);
}
GetReflowAndBoundingMetricsFor(frameNum, sizeNum, bmNum);
GetReflowAndBoundingMetricsFor(frameDen, sizeDen, bmDen);
nsPresContext* presContext = PresContext();
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
nsRefPtr<nsFontMetrics> fm;
nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm));
aRenderingContext.SetFont(fm);
nscoord defaultRuleThickness, axisHeight;
GetRuleThickness(aRenderingContext, fm, defaultRuleThickness);
GetAxisHeight(aRenderingContext, fm, axisHeight);
nsEmbellishData coreData;
GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
// see if the linethickness attribute is there
nsAutoString value;
GetAttribute(mContent, mPresentationData.mstyle, nsGkAtoms::linethickness_,
value);
mLineThickness = CalcLineThickness(presContext, mStyleContext, value,
onePixel, defaultRuleThickness);
// bevelled attribute
GetAttribute(mContent, mPresentationData.mstyle, nsGkAtoms::bevelled_,
value);
mIsBevelled = value.EqualsLiteral("true");
if (!mIsBevelled) {
mLineRect.height = mLineThickness;
// by default, leave at least one-pixel padding at either end, or use
// lspace & rspace that may come from <mo> if we are an 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 = NS_MAX(onePixel, coreData.leftSpace);
nscoord rightSpace = NS_MAX(onePixel, coreData.rightSpace);
//////////////////
// 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 (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) {
// C > T
numShift = numShift1;
denShift = denShift1;
}
else {
numShift = (0 < mLineRect.height) ? numShift2 : numShift3;
denShift = denShift2;
}
nscoord minClearance = 0;
nscoord actualClearance = 0;
nscoord actualRuleThickness = mLineThickness;
if (0 == actualRuleThickness) {
// Rule 15c, App. G, TeXbook
// min clearance between numerator and denominator
minClearance = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
7 * defaultRuleThickness : 3 * defaultRuleThickness;
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 = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
// 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.
minClearance = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
3 * defaultRuleThickness : defaultRuleThickness + onePixel;
// adjust numShift to maintain minClearance if needed
actualClearance =
(numShift - bmNum.descent) - (axisHeight + actualRuleThickness/2);
if (actualClearance < minClearance) {
numShift += (minClearance - actualClearance);
}
// adjust denShift to maintain minClearance if needed
actualClearance =
(axisHeight - actualRuleThickness/2) - (bmDen.ascent - denShift);
if (actualClearance < minClearance) {
denShift += (minClearance - actualClearance);
}
}
//////////////////
// Place Children
// XXX Need revisiting the width. TeX uses the exact width
// e.g. in $$\huge\frac{\displaystyle\int}{i}$$
nscoord width = NS_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
GetAttribute(mContent, mPresentationData.mstyle, 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
GetAttribute(mContent, mPresentationData.mstyle, nsGkAtoms::denomalign_,
value);
if (value.EqualsLiteral("left"))
dxDen = leftSpace;
else if (value.EqualsLiteral("right"))
dxDen = width - rightSpace - sizeDen.width;
mBoundingMetrics.rightBearing =
NS_MAX(dxNum + bmNum.rightBearing, dxDen + bmDen.rightBearing);
if (mBoundingMetrics.rightBearing < width - rightSpace)
mBoundingMetrics.rightBearing = width - rightSpace;
mBoundingMetrics.leftBearing =
NS_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.ascent = sizeNum.ascent + numShift;
aDesiredSize.height = aDesiredSize.ascent +
sizeDen.height - sizeDen.ascent + denShift;
aDesiredSize.width = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.ascent;
if (aPlaceOrigin) {
nscoord dy;
// place numerator
dy = 0;
FinishReflowChild(frameNum, presContext, nsnull, sizeNum, dxNum, dy, 0);
// place denominator
dy = aDesiredSize.height - sizeDen.height;
FinishReflowChild(frameDen, presContext, nsnull, sizeDen, dxDen, dy, 0);
// place the fraction bar - dy is top of bar
dy = aDesiredSize.ascent - (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 *
NS_MIN(2 * mLineThickness, slashMaxWidthConstant);
nscoord leftSpace = NS_MAX(padding, coreData.leftSpace);
nscoord rightSpace = NS_MAX(padding, coreData.rightSpace);
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 = NS_MAX(bmDen.ascent - bmNum.ascent,
bmNum.descent - bmDen.descent) / 2;
if (delta > 0) {
numShift += delta;
denShift += delta;
}
if (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) {
delta = NS_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 +
NS_MIN(slashMaxWidthConstant,
(mBoundingMetrics.ascent + mBoundingMetrics.descent) /
slashRatio);
}
// Set horizontal bounding metrics
mBoundingMetrics.leftBearing = leftSpace + bmNum.leftBearing;
mBoundingMetrics.rightBearing =
leftSpace + bmNum.width + mLineRect.width + bmDen.rightBearing;
mBoundingMetrics.width =
leftSpace + bmNum.width + mLineRect.width + bmDen.width + rightSpace;
// Set aDesiredSize
aDesiredSize.ascent = mBoundingMetrics.ascent + padding;
aDesiredSize.height =
mBoundingMetrics.ascent + mBoundingMetrics.descent + 2 * padding;
aDesiredSize.width = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.ascent;
if (aPlaceOrigin) {
FinishReflowChild(frameNum, presContext, nsnull, sizeNum,
leftSpace,
aDesiredSize.ascent - numShift - sizeNum.ascent, 0);
mLineRect.SetRect(leftSpace + bmNum.width,
aDesiredSize.ascent - mBoundingMetrics.ascent,
mLineRect.width,
aDesiredSize.height - 2 * padding);
FinishReflowChild(frameDen, presContext, nsnull, sizeDen,
leftSpace + bmNum.width + mLineRect.width,
aDesiredSize.ascent + denShift - sizeDen.ascent, 0);
}
}
return NS_OK;
}
/* virtual */ nsresult
nsMathMLmfracFrame::Place(nsIRenderingContext& aRenderingContext,
PRBool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize)
{
////////////////////////////////////
// Get the children's desired sizes
nsBoundingMetrics bmNum, bmDen;
nsHTMLReflowMetrics sizeNum;
nsHTMLReflowMetrics sizeDen;
nsIFrame* frameDen = nsnull;
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
NS_WARNING("invalid markup");
return ReflowError(aRenderingContext, aDesiredSize);
}
GetReflowAndBoundingMetricsFor(frameNum, sizeNum, bmNum);
GetReflowAndBoundingMetricsFor(frameDen, sizeDen, bmDen);
//////////////////
// Get shifts
nsPresContext* presContext = PresContext();
nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
aRenderingContext.SetFont(GetStyleFont()->mFont, nsnull);
nsCOMPtr<nsIFontMetrics> fm;
aRenderingContext.GetFontMetrics(*getter_AddRefs(fm));
nscoord defaultRuleThickness, axisHeight;
GetRuleThickness(aRenderingContext, fm, defaultRuleThickness);
GetAxisHeight(aRenderingContext, fm, axisHeight);
// by default, leave at least one-pixel padding at either end, or use
// lspace & rspace that may come from <mo> if we are an 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)
nsEmbellishData coreData;
GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
nscoord leftSpace = PR_MAX(onePixel, coreData.leftSpace);
nscoord rightSpace = PR_MAX(onePixel, coreData.rightSpace);
// see if the linethickness attribute is there
nsAutoString value;
GetAttribute(mContent, mPresentationData.mstyle, nsGkAtoms::linethickness_, value);
mLineRect.height = CalcLineThickness(presContext, mStyleContext, value,
onePixel, defaultRuleThickness);
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 (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) {
// C > T
numShift = numShift1;
denShift = denShift1;
}
else {
numShift = (0 < mLineRect.height) ? numShift2 : numShift3;
denShift = denShift2;
}
nscoord minClearance = 0;
nscoord actualClearance = 0;
nscoord actualRuleThickness = mLineRect.height;
if (0 == actualRuleThickness) {
// Rule 15c, App. G, TeXbook
// min clearance between numerator and denominator
minClearance = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
7 * defaultRuleThickness : 3 * defaultRuleThickness;
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 = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
// 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.
minClearance = (NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags)) ?
3 * defaultRuleThickness : defaultRuleThickness + onePixel;
// adjust numShift to maintain minClearance if needed
actualClearance =
(numShift - bmNum.descent) - (axisHeight + actualRuleThickness/2);
if (actualClearance < minClearance) {
numShift += (minClearance - actualClearance);
}
// adjust denShift to maintain minClearance if needed
actualClearance =
(axisHeight - actualRuleThickness/2) - (bmDen.ascent - denShift);
if (actualClearance < minClearance) {
denShift += (minClearance - actualClearance);
}
}
//////////////////
// Place Children
// XXX Need revisiting the width. TeX uses the exact width
// e.g. in $$\huge\frac{\displaystyle\int}{i}$$
nscoord width = PR_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
GetAttribute(mContent, mPresentationData.mstyle, 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
GetAttribute(mContent, mPresentationData.mstyle, nsGkAtoms::denomalign_,
value);
if (value.EqualsLiteral("left"))
dxDen = leftSpace;
else if (value.EqualsLiteral("right"))
dxDen = width - rightSpace - sizeDen.width;
mBoundingMetrics.rightBearing =
PR_MAX(dxNum + bmNum.rightBearing, dxDen + bmDen.rightBearing);
if (mBoundingMetrics.rightBearing < width - rightSpace)
mBoundingMetrics.rightBearing = width - rightSpace;
mBoundingMetrics.leftBearing =
PR_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.ascent = sizeNum.ascent + numShift;
aDesiredSize.height = aDesiredSize.ascent +
sizeDen.height - sizeDen.ascent + denShift;
aDesiredSize.width = mBoundingMetrics.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.ascent;
if (aPlaceOrigin) {
nscoord dy;
// place numerator
dy = 0;
FinishReflowChild(frameNum, presContext, nsnull, sizeNum, dxNum, dy, 0);
// place denominator
dy = aDesiredSize.height - sizeDen.height;
FinishReflowChild(frameDen, presContext, nsnull, sizeDen, dxDen, dy, 0);
// place the fraction bar - dy is top of bar
dy = aDesiredSize.ascent - (axisHeight + actualRuleThickness/2);
mLineRect.SetRect(leftSpace, dy, width - (leftSpace + rightSpace), actualRuleThickness);
}
return NS_OK;
}
NS_IMETHODIMP
nsMathMLmtableOuterFrame::Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
nsresult rv;
nsAutoString value;
// we want to return a table that is anchored according to the align attribute
rv = nsTableOuterFrame::Reflow(aPresContext, aDesiredSize, aReflowState,
aStatus);
NS_ASSERTION(aDesiredSize.height >= 0, "illegal height for mtable");
NS_ASSERTION(aDesiredSize.width >= 0, "illegal width for mtable");
// see if the user has set the align attribute on the <mtable>
// XXX should we also check <mstyle> ?
PRInt32 rowIndex = 0;
eAlign tableAlign = eAlign_axis;
GetAttribute(mContent, nsnull, nsGkAtoms::align, value);
if (!value.IsEmpty()) {
ParseAlignAttribute(value, tableAlign, rowIndex);
}
// adjustments if there is a specified row from where to anchor the table
// (conceptually: when there is no row of reference, picture the table as if
// it is wrapped in a single big fictional row at dy = 0, this way of
// doing so allows us to have a single code path for all cases).
nscoord dy = 0;
nscoord height = aDesiredSize.height;
nsIFrame* rowFrame = nsnull;
if (rowIndex) {
rowFrame = GetRowFrameAt(aPresContext, rowIndex);
if (rowFrame) {
// translate the coordinates to be relative to us
nsIFrame* frame = rowFrame;
height = frame->GetSize().height;
do {
dy += frame->GetPosition().y;
frame = frame->GetParent();
} while (frame != this);
}
}
switch (tableAlign) {
case eAlign_top:
aDesiredSize.ascent = dy;
break;
case eAlign_bottom:
aDesiredSize.ascent = dy + height;
break;
case eAlign_center:
aDesiredSize.ascent = dy + height/2;
break;
case eAlign_baseline:
if (rowFrame) {
// anchor the table on the baseline of the row of reference
nscoord rowAscent = ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent();
if (rowAscent) { // the row has at least one cell with 'vertical-align: baseline'
aDesiredSize.ascent = dy + rowAscent;
break;
}
}
// in other situations, fallback to center
aDesiredSize.ascent = dy + height/2;
break;
case eAlign_axis:
default: {
// XXX should instead use style data from the row of reference here ?
aReflowState.rendContext->SetFont(GetStyleFont()->mFont, nsnull,
aPresContext->GetUserFontSet());
nsCOMPtr<nsIFontMetrics> fm;
aReflowState.rendContext->GetFontMetrics(*getter_AddRefs(fm));
nscoord axisHeight;
GetAxisHeight(*aReflowState.rendContext, fm, axisHeight);
if (rowFrame) {
// anchor the table on the axis of the row of reference
// XXX fallback to baseline because it is a hard problem
// XXX need to fetch the axis of the row; would need rowalign=axis to work better
nscoord rowAscent = ((nsTableRowFrame*)rowFrame)->GetMaxCellAscent();
if (rowAscent) { // the row has at least one cell with 'vertical-align: baseline'
aDesiredSize.ascent = dy + rowAscent;
break;
}
}
// in other situations, fallback to using half of the height
aDesiredSize.ascent = dy + height/2 + axisHeight;
}
}
mReference.x = 0;
mReference.y = aDesiredSize.ascent;
// just make-up a bounding metrics
mBoundingMetrics.Clear();
mBoundingMetrics.ascent = aDesiredSize.ascent;
mBoundingMetrics.descent = aDesiredSize.height - aDesiredSize.ascent;
mBoundingMetrics.width = aDesiredSize.width;
mBoundingMetrics.leftBearing = 0;
mBoundingMetrics.rightBearing = aDesiredSize.width;
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
return rv;
}
