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; }