forked from mirrors/gecko-dev
662 lines
24 KiB
C++
662 lines
24 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "nsMathMLmfracFrame.h"
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#include "gfxUtils.h"
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#include "mozilla/gfx/2D.h"
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#include "mozilla/RefPtr.h"
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#include "nsLayoutUtils.h"
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#include "nsPresContext.h"
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#include "nsDisplayList.h"
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#include "gfxContext.h"
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#include "nsMathMLElement.h"
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#include <algorithm>
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#include "gfxMathTable.h"
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using namespace mozilla;
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using namespace mozilla::gfx;
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//
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// <mfrac> -- form a fraction from two subexpressions - implementation
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//
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// various fraction line thicknesses (multiplicative values of the default rule thickness)
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#define THIN_FRACTION_LINE 0.5f
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#define THIN_FRACTION_LINE_MINIMUM_PIXELS 1 // minimum of 1 pixel
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#define THICK_FRACTION_LINE 2.0f
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#define THICK_FRACTION_LINE_MINIMUM_PIXELS 2 // minimum of 2 pixels
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nsIFrame*
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NS_NewMathMLmfracFrame(nsIPresShell* aPresShell, ComputedStyle* aStyle)
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{
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return new (aPresShell) nsMathMLmfracFrame(aStyle);
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}
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NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmfracFrame)
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nsMathMLmfracFrame::~nsMathMLmfracFrame()
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{
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}
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eMathMLFrameType
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nsMathMLmfracFrame::GetMathMLFrameType()
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{
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// frac is "inner" in TeXBook, Appendix G, rule 15e. See also page 170.
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return eMathMLFrameType_Inner;
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}
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uint8_t
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nsMathMLmfracFrame::ScriptIncrement(nsIFrame* aFrame)
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{
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if (!StyleFont()->mMathDisplay &&
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aFrame && (mFrames.FirstChild() == aFrame ||
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mFrames.LastChild() == aFrame)) {
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return 1;
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}
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return 0;
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}
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NS_IMETHODIMP
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nsMathMLmfracFrame::TransmitAutomaticData()
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{
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// The TeXbook (Ch 17. p.141) says the numerator inherits the compression
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// while the denominator is compressed
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UpdatePresentationDataFromChildAt(1, 1,
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NS_MATHML_COMPRESSED,
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NS_MATHML_COMPRESSED);
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// If displaystyle is false, then scriptlevel is incremented, so notify the
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// children of this.
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if (!StyleFont()->mMathDisplay) {
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PropagateFrameFlagFor(mFrames.FirstChild(),
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NS_FRAME_MATHML_SCRIPT_DESCENDANT);
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PropagateFrameFlagFor(mFrames.LastChild(),
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NS_FRAME_MATHML_SCRIPT_DESCENDANT);
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}
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// if our numerator is an embellished operator, let its state bubble to us
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GetEmbellishDataFrom(mFrames.FirstChild(), mEmbellishData);
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if (NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags)) {
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// even when embellished, we need to record that <mfrac> won't fire
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// Stretch() on its embellished child
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mEmbellishData.direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
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}
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return NS_OK;
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}
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nscoord
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nsMathMLmfracFrame::CalcLineThickness(nsPresContext* aPresContext,
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ComputedStyle* aComputedStyle,
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nsString& aThicknessAttribute,
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nscoord onePixel,
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nscoord aDefaultRuleThickness,
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float aFontSizeInflation)
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{
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nscoord defaultThickness = aDefaultRuleThickness;
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nscoord lineThickness = aDefaultRuleThickness;
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nscoord minimumThickness = onePixel;
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// linethickness
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//
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// "Specifies the thickness of the horizontal 'fraction bar', or 'rule'. The
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// default value is 'medium', 'thin' is thinner, but visible, 'thick' is
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// thicker; the exact thickness of these is left up to the rendering agent."
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//
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// values: length | "thin" | "medium" | "thick"
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// default: medium
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//
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if (!aThicknessAttribute.IsEmpty()) {
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if (aThicknessAttribute.EqualsLiteral("thin")) {
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lineThickness = NSToCoordFloor(defaultThickness * THIN_FRACTION_LINE);
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minimumThickness = onePixel * THIN_FRACTION_LINE_MINIMUM_PIXELS;
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// should visually decrease by at least one pixel, if default is not a pixel
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if (defaultThickness > onePixel && lineThickness > defaultThickness - onePixel)
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lineThickness = defaultThickness - onePixel;
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}
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else if (aThicknessAttribute.EqualsLiteral("medium")) {
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// medium is default
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}
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else if (aThicknessAttribute.EqualsLiteral("thick")) {
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lineThickness = NSToCoordCeil(defaultThickness * THICK_FRACTION_LINE);
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minimumThickness = onePixel * THICK_FRACTION_LINE_MINIMUM_PIXELS;
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// should visually increase by at least one pixel
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if (lineThickness < defaultThickness + onePixel)
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lineThickness = defaultThickness + onePixel;
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}
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else {
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// length value
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lineThickness = defaultThickness;
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ParseNumericValue(aThicknessAttribute, &lineThickness,
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nsMathMLElement::PARSE_ALLOW_UNITLESS,
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aPresContext, aComputedStyle, aFontSizeInflation);
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}
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}
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// use minimum if the lineThickness is a non-zero value less than minimun
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if (lineThickness && lineThickness < minimumThickness)
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lineThickness = minimumThickness;
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return lineThickness;
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}
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void
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nsMathMLmfracFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
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const nsDisplayListSet& aLists)
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{
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/////////////
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// paint the numerator and denominator
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nsMathMLContainerFrame::BuildDisplayList(aBuilder, aLists);
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/////////////
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// paint the fraction line
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if (mIsBevelled) {
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DisplaySlash(aBuilder, this, mLineRect, mLineThickness, aLists);
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} else {
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DisplayBar(aBuilder, this, mLineRect, aLists);
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}
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}
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nsresult
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nsMathMLmfracFrame::AttributeChanged(int32_t aNameSpaceID,
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nsAtom* aAttribute,
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int32_t aModType)
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{
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if (nsGkAtoms::linethickness_ == aAttribute) {
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InvalidateFrame();
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}
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return
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nsMathMLContainerFrame::AttributeChanged(aNameSpaceID, aAttribute,
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aModType);
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}
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/* virtual */ nsresult
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nsMathMLmfracFrame::MeasureForWidth(DrawTarget* aDrawTarget,
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ReflowOutput& aDesiredSize)
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{
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return PlaceInternal(aDrawTarget, false, aDesiredSize, true);
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}
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nscoord
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nsMathMLmfracFrame::FixInterFrameSpacing(ReflowOutput& aDesiredSize)
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{
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nscoord gap = nsMathMLContainerFrame::FixInterFrameSpacing(aDesiredSize);
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if (!gap) return 0;
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mLineRect.MoveBy(gap, 0);
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return gap;
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}
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/* virtual */ nsresult
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nsMathMLmfracFrame::Place(DrawTarget* aDrawTarget,
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bool aPlaceOrigin,
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ReflowOutput& aDesiredSize)
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{
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return PlaceInternal(aDrawTarget, aPlaceOrigin, aDesiredSize, false);
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}
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nsresult
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nsMathMLmfracFrame::PlaceInternal(DrawTarget* aDrawTarget,
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bool aPlaceOrigin,
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ReflowOutput& aDesiredSize,
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bool aWidthOnly)
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{
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////////////////////////////////////
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// Get the children's desired sizes
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nsBoundingMetrics bmNum, bmDen;
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ReflowOutput sizeNum(aDesiredSize.GetWritingMode());
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ReflowOutput sizeDen(aDesiredSize.GetWritingMode());
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nsIFrame* frameDen = nullptr;
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nsIFrame* frameNum = mFrames.FirstChild();
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if (frameNum)
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frameDen = frameNum->GetNextSibling();
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if (!frameNum || !frameDen || frameDen->GetNextSibling()) {
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// report an error, encourage people to get their markups in order
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if (aPlaceOrigin) {
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ReportChildCountError();
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}
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return ReflowError(aDrawTarget, aDesiredSize);
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}
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GetReflowAndBoundingMetricsFor(frameNum, sizeNum, bmNum);
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GetReflowAndBoundingMetricsFor(frameDen, sizeDen, bmDen);
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nsPresContext* presContext = PresContext();
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nscoord onePixel = nsPresContext::CSSPixelsToAppUnits(1);
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float fontSizeInflation = nsLayoutUtils::FontSizeInflationFor(this);
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RefPtr<nsFontMetrics> fm =
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nsLayoutUtils::GetFontMetricsForFrame(this, fontSizeInflation);
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nscoord defaultRuleThickness, axisHeight;
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nscoord oneDevPixel = fm->AppUnitsPerDevPixel();
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gfxFont* mathFont = fm->GetThebesFontGroup()->GetFirstMathFont();
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if (mathFont) {
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defaultRuleThickness = mathFont->MathTable()->
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Constant(gfxMathTable::FractionRuleThickness, oneDevPixel);
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} else {
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GetRuleThickness(aDrawTarget, fm, defaultRuleThickness);
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}
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GetAxisHeight(aDrawTarget, fm, axisHeight);
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bool outermostEmbellished = false;
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if (mEmbellishData.coreFrame) {
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nsEmbellishData parentData;
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GetEmbellishDataFrom(GetParent(), parentData);
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outermostEmbellished = parentData.coreFrame != mEmbellishData.coreFrame;
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}
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// see if the linethickness attribute is there
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nsAutoString value;
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mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::linethickness_, value);
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mLineThickness = CalcLineThickness(presContext, mComputedStyle, value,
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onePixel, defaultRuleThickness,
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fontSizeInflation);
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// bevelled attribute
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mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::bevelled_, value);
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mIsBevelled = value.EqualsLiteral("true");
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bool displayStyle = StyleFont()->mMathDisplay == NS_MATHML_DISPLAYSTYLE_BLOCK;
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if (!mIsBevelled) {
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mLineRect.height = mLineThickness;
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// by default, leave at least one-pixel padding at either end, and add
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// lspace & rspace that may come from <mo> if we are an outermost
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// embellished container (we fetch values from the core since they may use
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// units that depend on style data, and style changes could have occurred
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// in the core since our last visit there)
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nscoord leftSpace = onePixel;
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nscoord rightSpace = onePixel;
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if (outermostEmbellished) {
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nsEmbellishData coreData;
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GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
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leftSpace += StyleVisibility()->mDirection ?
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coreData.trailingSpace : coreData.leadingSpace;
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rightSpace += StyleVisibility()->mDirection ?
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coreData.leadingSpace : coreData.trailingSpace;
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}
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nscoord actualRuleThickness = mLineThickness;
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//////////////////
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// Get shifts
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nscoord numShift = 0;
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nscoord denShift = 0;
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// Rule 15b, App. G, TeXbook
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nscoord numShift1, numShift2, numShift3;
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nscoord denShift1, denShift2;
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GetNumeratorShifts(fm, numShift1, numShift2, numShift3);
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GetDenominatorShifts(fm, denShift1, denShift2);
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if (0 == actualRuleThickness) {
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numShift = displayStyle ? numShift1 : numShift3;
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denShift = displayStyle ? denShift1 : denShift2;
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if (mathFont) {
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numShift = mathFont->
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MathTable()->Constant(displayStyle ?
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gfxMathTable::StackTopDisplayStyleShiftUp :
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gfxMathTable::StackTopShiftUp,
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oneDevPixel);
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denShift = mathFont->
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MathTable()->Constant(displayStyle ?
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gfxMathTable::StackBottomDisplayStyleShiftDown :
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gfxMathTable::StackBottomShiftDown,
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oneDevPixel);
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}
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} else {
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numShift = displayStyle ? numShift1 : numShift2;
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denShift = displayStyle ? denShift1 : denShift2;
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if (mathFont) {
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numShift = mathFont->MathTable()->
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Constant(displayStyle ?
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gfxMathTable::FractionNumeratorDisplayStyleShiftUp :
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gfxMathTable::FractionNumeratorShiftUp,
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oneDevPixel);
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denShift = mathFont->MathTable()->
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Constant(displayStyle ?
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gfxMathTable::FractionDenominatorDisplayStyleShiftDown :
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gfxMathTable::FractionDenominatorShiftDown,
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oneDevPixel);
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}
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}
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if (0 == actualRuleThickness) {
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// Rule 15c, App. G, TeXbook
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// min clearance between numerator and denominator
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nscoord minClearance = displayStyle ?
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7 * defaultRuleThickness : 3 * defaultRuleThickness;
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if (mathFont) {
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minClearance = mathFont->MathTable()->
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Constant(displayStyle ?
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gfxMathTable::StackDisplayStyleGapMin :
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gfxMathTable::StackGapMin,
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oneDevPixel);
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}
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// Factor in axis height
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// http://www.mathml-association.org/MathMLinHTML5/S3.html#SS3.SSS2
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numShift += axisHeight;
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denShift += axisHeight;
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nscoord actualClearance =
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(numShift - bmNum.descent) - (bmDen.ascent - denShift);
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// actualClearance should be >= minClearance
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if (actualClearance < minClearance) {
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nscoord halfGap = (minClearance - actualClearance)/2;
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numShift += halfGap;
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denShift += halfGap;
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}
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}
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else {
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// Rule 15d, App. G, TeXbook
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// min clearance between numerator or denominator and middle of bar
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// TeX has a different interpretation of the thickness.
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// Try $a \above10pt b$ to see. Here is what TeX does:
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// minClearance = displayStyle ?
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// 3 * actualRuleThickness : actualRuleThickness;
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// we slightly depart from TeX here. We use the defaultRuleThickness instead
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// of the value coming from the linethickness attribute, i.e., we recover what
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// TeX does if the user hasn't set linethickness. But when the linethickness
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// is set, we avoid the wide gap problem.
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nscoord minClearanceNum = displayStyle ?
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3 * defaultRuleThickness : defaultRuleThickness + onePixel;
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nscoord minClearanceDen = minClearanceNum;
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if (mathFont) {
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minClearanceNum = mathFont->
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MathTable()->Constant(displayStyle ?
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gfxMathTable::FractionNumDisplayStyleGapMin :
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gfxMathTable::FractionNumeratorGapMin,
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oneDevPixel);
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minClearanceDen = mathFont->
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MathTable()->Constant(displayStyle ?
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gfxMathTable::FractionDenomDisplayStyleGapMin :
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gfxMathTable::FractionDenominatorGapMin,
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oneDevPixel);
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}
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// adjust numShift to maintain minClearanceNum if needed
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nscoord actualClearanceNum =
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(numShift - bmNum.descent) - (axisHeight + actualRuleThickness/2);
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if (actualClearanceNum < minClearanceNum) {
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numShift += (minClearanceNum - actualClearanceNum);
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}
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// adjust denShift to maintain minClearanceDen if needed
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nscoord actualClearanceDen =
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(axisHeight - actualRuleThickness/2) - (bmDen.ascent - denShift);
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if (actualClearanceDen < minClearanceDen) {
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denShift += (minClearanceDen - actualClearanceDen);
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}
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}
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//////////////////
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// Place Children
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// XXX Need revisiting the width. TeX uses the exact width
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// e.g. in $$\huge\frac{\displaystyle\int}{i}$$
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nscoord width = std::max(bmNum.width, bmDen.width);
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nscoord dxNum = leftSpace + (width - sizeNum.Width())/2;
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nscoord dxDen = leftSpace + (width - sizeDen.Width())/2;
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width += leftSpace + rightSpace;
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// see if the numalign attribute is there
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mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::numalign_, value);
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if (value.EqualsLiteral("left"))
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dxNum = leftSpace;
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else if (value.EqualsLiteral("right"))
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dxNum = width - rightSpace - sizeNum.Width();
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// see if the denomalign attribute is there
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mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::denomalign_, value);
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if (value.EqualsLiteral("left"))
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dxDen = leftSpace;
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else if (value.EqualsLiteral("right"))
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dxDen = width - rightSpace - sizeDen.Width();
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mBoundingMetrics.rightBearing =
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std::max(dxNum + bmNum.rightBearing, dxDen + bmDen.rightBearing);
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if (mBoundingMetrics.rightBearing < width - rightSpace)
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mBoundingMetrics.rightBearing = width - rightSpace;
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mBoundingMetrics.leftBearing =
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std::min(dxNum + bmNum.leftBearing, dxDen + bmDen.leftBearing);
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if (mBoundingMetrics.leftBearing > leftSpace)
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mBoundingMetrics.leftBearing = leftSpace;
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mBoundingMetrics.ascent = bmNum.ascent + numShift;
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mBoundingMetrics.descent = bmDen.descent + denShift;
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mBoundingMetrics.width = width;
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aDesiredSize.SetBlockStartAscent(sizeNum.BlockStartAscent() + numShift);
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aDesiredSize.Height() = aDesiredSize.BlockStartAscent() +
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sizeDen.Height() - sizeDen.BlockStartAscent() + denShift;
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aDesiredSize.Width() = mBoundingMetrics.width;
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aDesiredSize.mBoundingMetrics = mBoundingMetrics;
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mReference.x = 0;
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mReference.y = aDesiredSize.BlockStartAscent();
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if (aPlaceOrigin) {
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nscoord dy;
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// place numerator
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dy = 0;
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FinishReflowChild(frameNum, presContext, sizeNum, nullptr, dxNum, dy, 0);
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// place denominator
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dy = aDesiredSize.Height() - sizeDen.Height();
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FinishReflowChild(frameDen, presContext, sizeDen, nullptr, dxDen, dy, 0);
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// place the fraction bar - dy is top of bar
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dy = aDesiredSize.BlockStartAscent() - (axisHeight + actualRuleThickness/2);
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mLineRect.SetRect(leftSpace, dy, width - (leftSpace + rightSpace),
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actualRuleThickness);
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}
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} else {
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nscoord numShift = 0.0;
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nscoord denShift = 0.0;
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nscoord padding = 3 * defaultRuleThickness;
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nscoord slashRatio = 3;
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// Define the constant used in the expression of the maximum width
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nscoord em = fm->EmHeight();
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nscoord slashMaxWidthConstant = 2 * em;
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// For large line thicknesses the minimum slash height is limited to the
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// largest expected height of a fraction
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nscoord slashMinHeight = slashRatio *
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std::min(2 * mLineThickness, slashMaxWidthConstant);
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nscoord leadingSpace = padding;
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nscoord trailingSpace = padding;
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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;
|
|
}
|
|
|
|
class nsDisplayMathMLSlash : public nsDisplayItem {
|
|
public:
|
|
nsDisplayMathMLSlash(nsDisplayListBuilder* aBuilder,
|
|
nsIFrame* aFrame, const nsRect& aRect,
|
|
nscoord aThickness, bool aRTL)
|
|
: nsDisplayItem(aBuilder, aFrame), mRect(aRect), mThickness(aThickness),
|
|
mRTL(aRTL) {
|
|
MOZ_COUNT_CTOR(nsDisplayMathMLSlash);
|
|
}
|
|
#ifdef NS_BUILD_REFCNT_LOGGING
|
|
virtual ~nsDisplayMathMLSlash() {
|
|
MOZ_COUNT_DTOR(nsDisplayMathMLSlash);
|
|
}
|
|
#endif
|
|
|
|
virtual void Paint(nsDisplayListBuilder* aBuilder,
|
|
gfxContext* aCtx) override;
|
|
NS_DISPLAY_DECL_NAME("MathMLSlash", TYPE_MATHML_SLASH)
|
|
|
|
private:
|
|
nsRect mRect;
|
|
nscoord mThickness;
|
|
bool mRTL;
|
|
};
|
|
|
|
void nsDisplayMathMLSlash::Paint(nsDisplayListBuilder* aBuilder,
|
|
gfxContext* aCtx)
|
|
{
|
|
DrawTarget& aDrawTarget = *aCtx->GetDrawTarget();
|
|
|
|
// get the gfxRect
|
|
nsPresContext* presContext = mFrame->PresContext();
|
|
Rect rect = NSRectToRect(mRect + ToReferenceFrame(),
|
|
presContext->AppUnitsPerDevPixel());
|
|
|
|
ColorPattern color(ToDeviceColor(
|
|
mFrame->GetVisitedDependentColor(&nsStyleText::mWebkitTextFillColor)));
|
|
|
|
// draw the slash as a parallelogram
|
|
Point delta = Point(presContext->AppUnitsToGfxUnits(mThickness), 0);
|
|
RefPtr<PathBuilder> builder = aDrawTarget.CreatePathBuilder();
|
|
if (mRTL) {
|
|
builder->MoveTo(rect.TopLeft());
|
|
builder->LineTo(rect.TopLeft() + delta);
|
|
builder->LineTo(rect.BottomRight());
|
|
builder->LineTo(rect.BottomRight() - delta);
|
|
} else {
|
|
builder->MoveTo(rect.BottomLeft());
|
|
builder->LineTo(rect.BottomLeft() + delta);
|
|
builder->LineTo(rect.TopRight());
|
|
builder->LineTo(rect.TopRight() - delta);
|
|
}
|
|
RefPtr<Path> path = builder->Finish();
|
|
aDrawTarget.Fill(path, color);
|
|
}
|
|
|
|
void
|
|
nsMathMLmfracFrame::DisplaySlash(nsDisplayListBuilder* aBuilder,
|
|
nsIFrame* aFrame, const nsRect& aRect,
|
|
nscoord aThickness,
|
|
const nsDisplayListSet& aLists) {
|
|
if (!aFrame->StyleVisibility()->IsVisible() || aRect.IsEmpty())
|
|
return;
|
|
|
|
aLists.Content()->AppendToTop(
|
|
MakeDisplayItem<nsDisplayMathMLSlash>(aBuilder, aFrame, aRect, aThickness,
|
|
StyleVisibility()->mDirection));
|
|
}
|