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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
#ifndef nsMathMLContainerFrame_h___
#define nsMathMLContainerFrame_h___
#include "mozilla/Attributes.h"
#include "nsContainerFrame.h"
#include "nsBlockFrame.h"
#include "nsInlineFrame.h"
#include "nsMathMLOperators.h"
#include "nsMathMLFrame.h"
#include "mozilla/Likely.h"
namespace mozilla {
class PresShell;
} // namespace mozilla
/*
* Base class for MathML container frames. It acts like an inferred
* mrow. By default, this frame uses its Reflow() method to lay its
* children horizontally and ensure that their baselines are aligned.
* The Reflow() method relies upon Place() to position children.
* By overloading Place() in derived classes, it is therefore possible
* to position children in various customized ways.
*/
// Options for the preferred size at which to stretch our stretchy children
#define STRETCH_CONSIDER_ACTUAL_SIZE 0x00000001 // just use our current size
#define STRETCH_CONSIDER_EMBELLISHMENTS \
0x00000002 // size calculations include embellishments
class nsMathMLContainerFrame : public nsContainerFrame, public nsMathMLFrame {
public:
nsMathMLContainerFrame(ComputedStyle* aStyle, nsPresContext* aPresContext,
ClassID aID)
: nsContainerFrame(aStyle, aPresContext, aID) {}
NS_DECL_QUERYFRAME_TARGET(nsMathMLContainerFrame)
NS_DECL_QUERYFRAME
NS_DECL_ABSTRACT_FRAME(nsMathMLContainerFrame)
// --------------------------------------------------------------------------
// Overloaded nsMathMLFrame methods -- see documentation in nsIMathMLFrame.h
NS_IMETHOD
Stretch(DrawTarget* aDrawTarget, nsStretchDirection aStretchDirection,
nsBoundingMetrics& aContainerSize,
ReflowOutput& aDesiredStretchSize) override;
NS_IMETHOD
UpdatePresentationDataFromChildAt(int32_t aFirstIndex, int32_t aLastIndex,
uint32_t aFlagsValues,
uint32_t aFlagsToUpdate) override {
PropagatePresentationDataFromChildAt(this, aFirstIndex, aLastIndex,
aFlagsValues, aFlagsToUpdate);
return NS_OK;
}
// --------------------------------------------------------------------------
// Overloaded nsContainerFrame methods -- see documentation in nsIFrame.h
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override;
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override;
void RemoveFrame(DestroyContext&, ChildListID aListID,
nsIFrame* aOldFrame) override;
/**
* Both GetMinISize and GetPrefISize use the intrinsic width metrics
* returned by GetIntrinsicMetrics, including ink overflow.
*/
nscoord GetMinISize(gfxContext* aRenderingContext) override;
nscoord GetPrefISize(gfxContext* aRenderingContext) override;
/**
* Return the intrinsic horizontal metrics of the frame's content area.
*/
virtual void GetIntrinsicISizeMetrics(gfxContext* aRenderingContext,
ReflowOutput& aDesiredSize);
void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
void DidReflow(nsPresContext* aPresContext,
const ReflowInput* aReflowInput) override
{
mPresentationData.flags &= ~NS_MATHML_STRETCH_DONE;
return nsContainerFrame::DidReflow(aPresContext, aReflowInput);
}
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override;
bool ComputeCustomOverflow(mozilla::OverflowAreas& aOverflowAreas) override;
void MarkIntrinsicISizesDirty() override;
// Notification when an attribute is changed. The MathML module uses the
// following paradigm:
//
// 1. If the MathML frame class doesn't have any cached automatic data that
// depends on the attribute: we just reflow (e.g., this happens with
// <msub>, <msup>, <mmultiscripts>, etc). This is the default behavior
// implemented by this base class.
//
// 2. If the MathML frame class has cached automatic data that depends on
// the attribute:
// 2a. If the automatic data to update resides only within the descendants,
// we just re-layout them using ReLayoutChildren(this);
// (e.g., this happens with <ms>).
// 2b. If the automatic data to update affects us in some way, we ask our
// parent to re-layout its children using ReLayoutChildren(mParent);
// Therefore, there is an overhead here in that our siblings are
// re-laid too (e.g., this happens with <munder>, <mover>,
// <munderover>).
nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
int32_t aModType) override;
// helper function to apply mirroring to a horizontal coordinate, if needed.
nscoord MirrorIfRTL(nscoord aParentWidth, nscoord aChildWidth,
nscoord aChildLeading) {
return StyleVisibility()->mDirection == mozilla::StyleDirection::Rtl
? aParentWidth - aChildWidth - aChildLeading
: aChildLeading;
}
// --------------------------------------------------------------------------
// Additional methods
protected:
/* Place :
* This method is used to measure or position child frames and other
* elements. It may be called any number of times with aPlaceOrigin
* false to measure, and the final call of the Reflow process before
* returning from Reflow() or Stretch() will have aPlaceOrigin true
* to position the elements.
*
* IMPORTANT: This method uses GetReflowAndBoundingMetricsFor() which must
* have been set up with SaveReflowAndBoundingMetricsFor().
*
* The Place() method will use this information to compute the desired size
* of the frame.
*
* @param aPlaceOrigin [in]
* If aPlaceOrigin is false, compute your desired size using the
* information from GetReflowAndBoundingMetricsFor. However, child
* frames or other elements should not be repositioned.
*
* If aPlaceOrigin is true, reflow is finished. You should position
* all your children, and return your desired size. You should now
* use FinishReflowChild() on your children to complete post-reflow
* operations.
*
* @param aDesiredSize [out] parameter where you should return your desired
* size and your ascent/descent info. Compute your desired size using
* the information from GetReflowAndBoundingMetricsFor, and include
* any space you want for border/padding in the desired size you
* return.
*/
virtual nsresult Place(DrawTarget* aDrawTarget, bool aPlaceOrigin,
ReflowOutput& aDesiredSize);
// MeasureForWidth:
//
// A method used by nsMathMLContainerFrame::GetIntrinsicISize to get the
// width that a particular Place method desires. For most frames, this will
// just call the object's Place method. However <msqrt> and <menclose> use
// nsMathMLContainerFrame::GetIntrinsicISize to measure the child frames as
// if in an <mrow>, and so their frames implement MeasureForWidth to use
// nsMathMLContainerFrame::Place.
virtual nsresult MeasureForWidth(DrawTarget* aDrawTarget,
ReflowOutput& aDesiredSize);
// helper to re-sync the automatic data in our children and notify our parent
// to reflow us when changes (e.g., append/insert/remove) happen in our child
// list
virtual nsresult ChildListChanged(int32_t aModType);
// helper to get the preferred size that a container frame should use to fire
// the stretch on its stretchy child frames.
void GetPreferredStretchSize(DrawTarget* aDrawTarget, uint32_t aOptions,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aPreferredStretchSize);
// helper used by mstyle, mphantom, mpadded and mrow in their implementation
// of TransmitAutomaticData() to determine whether they are space-like.
nsresult TransmitAutomaticDataForMrowLikeElement();
public:
/*
* Helper to render the frame as a default mrow-like container when an error
* (typically invalid markup) was encountered during reflow. Parameters are
* the same as Place().
*/
nsresult PlaceAsMrow(DrawTarget* aDrawTarget, bool aPlaceOrigin,
ReflowOutput& aDesiredSize);
/*
* Helper to call ReportErrorToConsole for parse errors involving
* attribute/value pairs.
* @param aAttribute The attribute for which the parse error occured.
* @param aValue The value for which the parse error occured.
*/
nsresult ReportParseError(const char16_t* aAttribute, const char16_t* aValue);
/*
* Helper to call ReportErrorToConsole when certain tags
* have more than the expected amount of children.
*/
nsresult ReportChildCountError();
/*
* Helper to call ReportErrorToConsole when certain tags have
* invalid child tags
* @param aChildTag The tag which is forbidden in this context
*/
nsresult ReportInvalidChildError(nsAtom* aChildTag);
/*
* Helper to call ReportToConsole when an error occurs.
* @param aParams see nsContentUtils::ReportToConsole
*/
nsresult ReportErrorToConsole(
const char* aErrorMsgId,
const nsTArray<nsString>& aParams = nsTArray<nsString>());
// helper method to reflow a child frame. We are inline frames, and we don't
// know our positions until reflow is finished. That's why we ask the
// base method not to worry about our position.
void ReflowChild(nsIFrame* aKidFrame, nsPresContext* aPresContext,
ReflowOutput& aDesiredSize, const ReflowInput& aReflowInput,
nsReflowStatus& aStatus);
protected:
// helper to add the inter-spacing when <math> is the immediate parent.
// Since we don't (yet) handle the root <math> element ourselves, we need to
// take special care of the inter-frame spacing on elements for which <math>
// is the direct xml parent. This function will be repeatedly called from
// left to right on the childframes of <math>, and by so doing it will
// emulate the spacing that would have been done by a <mrow> container.
// e.g., it fixes <math> <mi>f</mi> <mo>q</mo> <mi>f</mi> <mo>I</mo> </math>
virtual nscoord FixInterFrameSpacing(ReflowOutput& aDesiredSize);
// helper method to complete the post-reflow hook and ensure that embellished
// operators don't terminate their Reflow without receiving a Stretch command.
virtual nsresult FinalizeReflow(DrawTarget* aDrawTarget,
ReflowOutput& aDesiredSize);
// Record metrics of a child frame for recovery through the following method
static void SaveReflowAndBoundingMetricsFor(
nsIFrame* aFrame, const ReflowOutput& aReflowOutput,
const nsBoundingMetrics& aBoundingMetrics);
// helper method to facilitate getting the reflow and bounding metrics of a
// child frame. The argument aMathMLFrameType, when non null, will return
// the 'type' of the frame, which is used to determine the inter-frame
// spacing.
// IMPORTANT: This function is only meant to be called in Place() methods as
// the information is available only when set up with the above method
// during Reflow/Stretch() and GetPrefISize().
static void GetReflowAndBoundingMetricsFor(
nsIFrame* aFrame, ReflowOutput& aReflowOutput,
nsBoundingMetrics& aBoundingMetrics,
eMathMLFrameType* aMathMLFrameType = nullptr);
// helper method to clear metrics saved with
// SaveReflowAndBoundingMetricsFor() from all child frames.
void ClearSavedChildMetrics();
// helper to let the update of presentation data pass through
// a subtree that may contain non-MathML container frames
static void PropagatePresentationDataFor(nsIFrame* aFrame,
uint32_t aFlagsValues,
uint32_t aFlagsToUpdate);
public:
static void PropagatePresentationDataFromChildAt(nsIFrame* aParentFrame,
int32_t aFirstChildIndex,
int32_t aLastChildIndex,
uint32_t aFlagsValues,
uint32_t aFlagsToUpdate);
// Sets flags on aFrame and all descendant frames
static void PropagateFrameFlagFor(nsIFrame* aFrame, nsFrameState aFlags);
// helper to let the rebuild of automatic data (presentation data
// and embellishement data) walk through a subtree that may contain
// non-MathML container frames. Note that this method re-builds the
// automatic data in the children -- not in aParentFrame itself (except
// for those particular operations that the parent frame may do in its
// TransmitAutomaticData()). The reason it works this way is because
// a container frame knows what it wants for its children, whereas children
// have no clue who their parent is. For example, it is <mfrac> who knows
// that its children have to be in scriptsizes, and has to transmit this
// information to them. Hence, when changes occur in a child frame, the child
// has to request the re-build from its parent. Unfortunately, the extra cost
// for this is that it will re-sync in the siblings of the child as well.
static void RebuildAutomaticDataForChildren(nsIFrame* aParentFrame);
// helper to blow away the automatic data cached in a frame's subtree and
// re-layout its subtree to reflect changes that may have happen. In the
// event where aParentFrame isn't a MathML frame, it will first walk up to
// the ancestor that is a MathML frame, and re-layout from there -- this is
// to guarantee that automatic data will be rebuilt properly. Note that this
// method re-builds the automatic data in the children -- not in the parent
// frame itself (except for those particular operations that the parent frame
// may do do its TransmitAutomaticData()). @see
// RebuildAutomaticDataForChildren
//
// aBits are the bits to pass to FrameNeedsReflow() when we call it.
static nsresult ReLayoutChildren(nsIFrame* aParentFrame);
protected:
// Helper method which positions child frames as an <mrow> on given baseline
// y = aBaseline starting from x = aOffsetX, calling FinishReflowChild()
// on the frames.
void PositionRowChildFrames(nscoord aOffsetX, nscoord aBaseline);
// A variant on FinishAndStoreOverflow() that uses the union of child
// overflows, the frame bounds, and mBoundingMetrics to set and store the
// overflow.
void GatherAndStoreOverflow(ReflowOutput* aMetrics);
/**
* Call DidReflow() if the NS_FRAME_IN_REFLOW frame bit is set on aFirst and
* all its next siblings up to, but not including, aStop.
* aStop == nullptr meaning all next siblings with the bit set.
* The method does nothing if aFirst == nullptr.
*/
static void DidReflowChildren(nsIFrame* aFirst, nsIFrame* aStop = nullptr);
/**
* Recompute mIntrinsicISize if it's not already up to date.
*/
void UpdateIntrinsicISize(gfxContext* aRenderingContext);
nscoord mIntrinsicISize = NS_INTRINSIC_ISIZE_UNKNOWN;
nscoord mBlockStartAscent = 0;
private:
class RowChildFrameIterator;
friend class RowChildFrameIterator;
};
// --------------------------------------------------------------------------
// Currently, to benefit from line-breaking inside the <math> element, <math> is
// simply mapping to nsBlockFrame or nsInlineFrame.
// A separate implemention needs to provide:
// 1) line-breaking
// 2) proper inter-frame spacing
// 3) firing of Stretch() (in which case FinalizeReflow() would have to be
// cleaned)
// Issues: If/when mathml becomes a pluggable component, the separation will be
// needed.
class nsMathMLmathBlockFrame final : public nsBlockFrame {
public:
NS_DECL_QUERYFRAME
NS_DECL_FRAMEARENA_HELPERS(nsMathMLmathBlockFrame)
friend nsContainerFrame* NS_NewMathMLmathBlockFrame(
mozilla::PresShell* aPresShell, ComputedStyle* aStyle);
// beware, mFrames is not set by nsBlockFrame
// cannot use mFrames{.FirstChild()|.etc} since the block code doesn't set
// mFrames
void SetInitialChildList(ChildListID aListID,
nsFrameList&& aChildList) override {
MOZ_ASSERT(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::Backdrop,
"unexpected frame list");
nsBlockFrame::SetInitialChildList(aListID, std::move(aChildList));
if (aListID == mozilla::FrameChildListID::Principal) {
// re-resolve our subtree to set any mathml-expected data
nsMathMLContainerFrame::RebuildAutomaticDataForChildren(this);
}
}
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsBlockFrame::AppendFrames(aListID, std::move(aFrameList));
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsBlockFrame::InsertFrames(aListID, aPrevFrame, aPrevFrameLine,
std::move(aFrameList));
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
void RemoveFrame(DestroyContext& aContext, ChildListID aListID,
nsIFrame* aOldFrame) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsBlockFrame::RemoveFrame(aContext, aListID, aOldFrame);
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
// See nsIMathMLFrame.h
bool IsMrowLike() {
return mFrames.FirstChild() != mFrames.LastChild() || !mFrames.FirstChild();
}
protected:
explicit nsMathMLmathBlockFrame(ComputedStyle* aStyle,
nsPresContext* aPresContext)
: nsBlockFrame(aStyle, aPresContext, kClassID) {}
virtual ~nsMathMLmathBlockFrame() = default;
};
// --------------
class nsMathMLmathInlineFrame final : public nsInlineFrame,
public nsMathMLFrame {
public:
NS_DECL_QUERYFRAME
NS_DECL_FRAMEARENA_HELPERS(nsMathMLmathInlineFrame)
friend nsContainerFrame* NS_NewMathMLmathInlineFrame(
mozilla::PresShell* aPresShell, ComputedStyle* aStyle);
void SetInitialChildList(ChildListID aListID,
nsFrameList&& aChildList) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal,
"unexpected frame list");
nsInlineFrame::SetInitialChildList(aListID, std::move(aChildList));
// re-resolve our subtree to set any mathml-expected data
nsMathMLContainerFrame::RebuildAutomaticDataForChildren(this);
}
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsInlineFrame::AppendFrames(aListID, std::move(aFrameList));
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsInlineFrame::InsertFrames(aListID, aPrevFrame, aPrevFrameLine,
std::move(aFrameList));
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
void RemoveFrame(DestroyContext& aContext, ChildListID aListID,
nsIFrame* aOldFrame) override {
NS_ASSERTION(aListID == mozilla::FrameChildListID::Principal ||
aListID == mozilla::FrameChildListID::NoReflowPrincipal,
"unexpected frame list");
nsInlineFrame::RemoveFrame(aContext, aListID, aOldFrame);
if (MOZ_LIKELY(aListID == mozilla::FrameChildListID::Principal)) {
nsMathMLContainerFrame::ReLayoutChildren(this);
}
}
bool IsMrowLike() override {
return mFrames.FirstChild() != mFrames.LastChild() || !mFrames.FirstChild();
}
protected:
explicit nsMathMLmathInlineFrame(ComputedStyle* aStyle,
nsPresContext* aPresContext)
: nsInlineFrame(aStyle, aPresContext, kClassID) {}
virtual ~nsMathMLmathInlineFrame() = default;
};
#endif /* nsMathMLContainerFrame_h___ */