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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsMathMLFrame_h___
#define nsMathMLFrame_h___
#include "mozilla/Attributes.h"
#include "nsFontMetrics.h"
#include "nsMathMLOperators.h"
#include "nsIMathMLFrame.h"
#include "nsBoundingMetrics.h"
#include "nsIFrame.h"
class nsMathMLChar;
class nsCSSValue;
namespace mozilla {
class nsDisplayListBuilder;
class nsDisplayListSet;
} // namespace mozilla
// Concrete base class with default methods that derived MathML frames can
// override
class nsMathMLFrame : public nsIMathMLFrame {
public:
// nsIMathMLFrame ---
virtual bool IsSpaceLike() override {
return NS_MATHML_IS_SPACE_LIKE(mPresentationData.flags);
}
NS_IMETHOD
GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics) override {
aBoundingMetrics = mBoundingMetrics;
return NS_OK;
}
NS_IMETHOD
SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics) override {
mBoundingMetrics = aBoundingMetrics;
return NS_OK;
}
NS_IMETHOD
SetReference(const nsPoint& aReference) override {
mReference = aReference;
return NS_OK;
}
virtual eMathMLFrameType GetMathMLFrameType() override;
NS_IMETHOD
Stretch(mozilla::gfx::DrawTarget* aDrawTarget,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aContainerSize,
mozilla::ReflowOutput& aDesiredStretchSize) override {
return NS_OK;
}
NS_IMETHOD
GetEmbellishData(nsEmbellishData& aEmbellishData) override {
aEmbellishData = mEmbellishData;
return NS_OK;
}
NS_IMETHOD
GetPresentationData(nsPresentationData& aPresentationData) override {
aPresentationData = mPresentationData;
return NS_OK;
}
NS_IMETHOD
InheritAutomaticData(nsIFrame* aParent) override;
NS_IMETHOD
TransmitAutomaticData() override { return NS_OK; }
NS_IMETHOD
UpdatePresentationData(uint32_t aFlagsValues,
uint32_t aFlagsToUpdate) override;
NS_IMETHOD
UpdatePresentationDataFromChildAt(int32_t aFirstIndex, int32_t aLastIndex,
uint32_t aFlagsValues,
uint32_t aFlagsToUpdate) override {
return NS_OK;
}
uint8_t ScriptIncrement(nsIFrame* aFrame) override { return 0; }
bool IsMrowLike() override { return false; }
// helper to get the mEmbellishData of a frame
// The MathML REC precisely defines an "embellished operator" as:
// - an <mo> element;
// - or one of the elements <msub>, <msup>, <msubsup>, <munder>, <mover>,
// <munderover>, <mmultiscripts>, <mfrac>, or <semantics>, whose first
// argument exists and is an embellished operator;
//- or one of the elements <mstyle>, <mphantom>, or <mpadded>, such that
// an <mrow> containing the same arguments would be an embellished
// operator;
// - or an <maction> element whose selected subexpression exists and is an
// embellished operator;
// - or an <mrow> whose arguments consist (in any order) of one embellished
// operator and zero or more spacelike elements.
static void GetEmbellishDataFrom(nsIFrame* aFrame,
nsEmbellishData& aEmbellishData);
// helper to get the presentation data of a frame. If aClimbTree is
// set to true and the frame happens to be surrounded by non-MathML
// helper frames needed for its support, we walk up the frame hierarchy
// until we reach a MathML ancestor or the <root> math element.
static void GetPresentationDataFrom(nsIFrame* aFrame,
nsPresentationData& aPresentationData,
bool aClimbTree = true);
// utilities to parse and retrieve numeric values in CSS units
// All values are stored in twips.
// @pre aLengthValue is the default length value of the attribute.
// @post aLengthValue is the length value computed from the attribute.
static void ParseNumericValue(const nsString& aString, nscoord* aLengthValue,
uint32_t aFlags, nsPresContext* aPresContext,
mozilla::ComputedStyle* aComputedStyle,
float aFontSizeInflation);
static nscoord CalcLength(nsPresContext* aPresContext,
mozilla::ComputedStyle* aComputedStyle,
const nsCSSValue& aCSSValue,
float aFontSizeInflation);
static eMathMLFrameType GetMathMLFrameTypeFor(nsIFrame* aFrame) {
if (aFrame->IsFrameOfType(nsIFrame::eMathML)) {
nsIMathMLFrame* mathMLFrame = do_QueryFrame(aFrame);
if (mathMLFrame) return mathMLFrame->GetMathMLFrameType();
}
return eMathMLFrameType_UNKNOWN;
}
// estimate of the italic correction
static void GetItalicCorrection(nsBoundingMetrics& aBoundingMetrics,
nscoord& aItalicCorrection) {
aItalicCorrection = aBoundingMetrics.rightBearing - aBoundingMetrics.width;
if (0 > aItalicCorrection) {
aItalicCorrection = 0;
}
}
static void GetItalicCorrection(nsBoundingMetrics& aBoundingMetrics,
nscoord& aLeftItalicCorrection,
nscoord& aRightItalicCorrection) {
aRightItalicCorrection =
aBoundingMetrics.rightBearing - aBoundingMetrics.width;
if (0 > aRightItalicCorrection) {
aRightItalicCorrection = 0;
}
aLeftItalicCorrection = -aBoundingMetrics.leftBearing;
if (0 > aLeftItalicCorrection) {
aLeftItalicCorrection = 0;
}
}
// helper methods for getting sup/subdrop's from a child
static void GetSubDropFromChild(nsIFrame* aChild, nscoord& aSubDrop,
float aFontSizeInflation);
static void GetSupDropFromChild(nsIFrame* aChild, nscoord& aSupDrop,
float aFontSizeInflation);
static void GetSkewCorrectionFromChild(nsIFrame* aChild,
nscoord& aSkewCorrection) {
// default is 0
// individual classes should over-ride this method if necessary
aSkewCorrection = 0;
}
// 2 levels of subscript shifts
static void GetSubScriptShifts(nsFontMetrics* fm, nscoord& aSubScriptShift1,
nscoord& aSubScriptShift2) {
nscoord xHeight = fm->XHeight();
aSubScriptShift1 = NSToCoordRound(150.000f / 430.556f * xHeight);
aSubScriptShift2 = NSToCoordRound(247.217f / 430.556f * xHeight);
}
// 3 levels of superscript shifts
static void GetSupScriptShifts(nsFontMetrics* fm, nscoord& aSupScriptShift1,
nscoord& aSupScriptShift2,
nscoord& aSupScriptShift3) {
nscoord xHeight = fm->XHeight();
aSupScriptShift1 = NSToCoordRound(412.892f / 430.556f * xHeight);
aSupScriptShift2 = NSToCoordRound(362.892f / 430.556f * xHeight);
aSupScriptShift3 = NSToCoordRound(288.889f / 430.556f * xHeight);
}
// these are TeX specific params not found in ordinary fonts
static void GetSubDrop(nsFontMetrics* fm, nscoord& aSubDrop) {
nscoord xHeight = fm->XHeight();
aSubDrop = NSToCoordRound(50.000f / 430.556f * xHeight);
}
static void GetSupDrop(nsFontMetrics* fm, nscoord& aSupDrop) {
nscoord xHeight = fm->XHeight();
aSupDrop = NSToCoordRound(386.108f / 430.556f * xHeight);
}
static void GetNumeratorShifts(nsFontMetrics* fm, nscoord& numShift1,
nscoord& numShift2, nscoord& numShift3) {
nscoord xHeight = fm->XHeight();
numShift1 = NSToCoordRound(676.508f / 430.556f * xHeight);
numShift2 = NSToCoordRound(393.732f / 430.556f * xHeight);
numShift3 = NSToCoordRound(443.731f / 430.556f * xHeight);
}
static void GetDenominatorShifts(nsFontMetrics* fm, nscoord& denShift1,
nscoord& denShift2) {
nscoord xHeight = fm->XHeight();
denShift1 = NSToCoordRound(685.951f / 430.556f * xHeight);
denShift2 = NSToCoordRound(344.841f / 430.556f * xHeight);
}
static void GetEmHeight(nsFontMetrics* fm, nscoord& emHeight) {
#if 0
// should switch to this API in order to scale with changes of TextZoom
emHeight = fm->EmHeight();
#else
emHeight = fm->Font().size.ToAppUnits();
#endif
}
static void GetAxisHeight(nsFontMetrics* fm, nscoord& axisHeight) {
axisHeight = NSToCoordRound(250.000f / 430.556f * fm->XHeight());
}
static void GetBigOpSpacings(nsFontMetrics* fm, nscoord& bigOpSpacing1,
nscoord& bigOpSpacing2, nscoord& bigOpSpacing3,
nscoord& bigOpSpacing4, nscoord& bigOpSpacing5) {
nscoord xHeight = fm->XHeight();
bigOpSpacing1 = NSToCoordRound(111.111f / 430.556f * xHeight);
bigOpSpacing2 = NSToCoordRound(166.667f / 430.556f * xHeight);
bigOpSpacing3 = NSToCoordRound(200.000f / 430.556f * xHeight);
bigOpSpacing4 = NSToCoordRound(600.000f / 430.556f * xHeight);
bigOpSpacing5 = NSToCoordRound(100.000f / 430.556f * xHeight);
}
static void GetRuleThickness(nsFontMetrics* fm, nscoord& ruleThickness) {
nscoord xHeight = fm->XHeight();
ruleThickness = NSToCoordRound(40.000f / 430.556f * xHeight);
}
// Some parameters are not accurately obtained using the x-height.
// Here are some slower variants to obtain the desired metrics
// by actually measuring some characters
static void GetRuleThickness(mozilla::gfx::DrawTarget* aDrawTarget,
nsFontMetrics* aFontMetrics,
nscoord& aRuleThickness);
static void GetAxisHeight(mozilla::gfx::DrawTarget* aDrawTarget,
nsFontMetrics* aFontMetrics, nscoord& aAxisHeight);
static void GetRadicalParameters(nsFontMetrics* aFontMetrics,
bool aDisplayStyle,
nscoord& aRadicalRuleThickness,
nscoord& aRadicalExtraAscender,
nscoord& aRadicalVerticalGap);
protected:
#if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
void DisplayBoundingMetrics(mozilla::nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame, const nsPoint& aPt,
const nsBoundingMetrics& aMetrics,
const nsDisplayListSet& aLists);
#endif
/**
* Display a solid rectangle in the frame's text color. Used for drawing
* fraction separators and root/sqrt overbars.
*/
void DisplayBar(mozilla::nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
const nsRect& aRect, const mozilla::nsDisplayListSet& aLists,
uint32_t aIndex = 0);
// information about the presentation policy of the frame
nsPresentationData mPresentationData;
// information about a container that is an embellished operator
nsEmbellishData mEmbellishData;
// Metrics that _exactly_ enclose the text of the frame
nsBoundingMetrics mBoundingMetrics;
// Reference point of the frame: mReference.y is the baseline
nsPoint mReference;
};
#endif /* nsMathMLFrame_h___ */