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;
}
