/* -*- 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/. */
#include "nsMathMLContainerFrame.h"
#include "gfxContext.h"
#include "gfxUtils.h"
#include "mozilla/Likely.h"
#include "mozilla/PresShell.h"
#include "mozilla/dom/MutationEventBinding.h"
#include "mozilla/gfx/2D.h"
#include "nsLayoutUtils.h"
#include "nsPresContext.h"
#include "nsNameSpaceManager.h"
#include "nsGkAtoms.h"
#include "nsDisplayList.h"
#include "nsIScriptError.h"
#include "nsContentUtils.h"
#include "mozilla/dom/MathMLElement.h"
using namespace mozilla;
using namespace mozilla::gfx;
//
// nsMathMLContainerFrame implementation
//
NS_QUERYFRAME_HEAD(nsMathMLContainerFrame)
NS_QUERYFRAME_ENTRY(nsIMathMLFrame)
NS_QUERYFRAME_ENTRY(nsMathMLContainerFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
// =============================================================================
// error handlers
// provide a feedback to the user when a frame with bad markup can not be
// rendered
nsresult nsMathMLContainerFrame::ReflowError(DrawTarget* aDrawTarget,
ReflowOutput& aDesiredSize) {
// clear all other flags and record that there is an error with this frame
mEmbellishData.flags = 0;
mPresentationData.flags = NS_MATHML_ERROR;
///////////////
// Set font
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetInflatedFontMetricsForFrame(this);
// bounding metrics
nsAutoString errorMsg;
errorMsg.AssignLiteral("invalid-markup");
mBoundingMetrics = nsLayoutUtils::AppUnitBoundsOfString(
errorMsg.get(), errorMsg.Length(), *fm, aDrawTarget);
// reflow metrics
WritingMode wm = aDesiredSize.GetWritingMode();
aDesiredSize.SetBlockStartAscent(fm->MaxAscent());
nscoord descent = fm->MaxDescent();
aDesiredSize.BSize(wm) = aDesiredSize.BlockStartAscent() + descent;
aDesiredSize.ISize(wm) = mBoundingMetrics.width;
// Also return our bounding metrics
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
return NS_OK;
}
class nsDisplayMathMLError : public nsPaintedDisplayItem {
public:
nsDisplayMathMLError(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame)
: nsPaintedDisplayItem(aBuilder, aFrame) {
MOZ_COUNT_CTOR(nsDisplayMathMLError);
}
MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayMathMLError)
virtual void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
NS_DISPLAY_DECL_NAME("MathMLError", TYPE_MATHML_ERROR)
};
void nsDisplayMathMLError::Paint(nsDisplayListBuilder* aBuilder,
gfxContext* aCtx) {
// Set color and font ...
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetFontMetricsForFrame(mFrame, 1.0f);
nsPoint pt = ToReferenceFrame();
int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
DrawTarget* drawTarget = aCtx->GetDrawTarget();
Rect rect = NSRectToSnappedRect(nsRect(pt, mFrame->GetSize()),
appUnitsPerDevPixel, *drawTarget);
ColorPattern red(ToDeviceColor(sRGBColor(1.f, 0.f, 0.f, 1.f)));
drawTarget->FillRect(rect, red);
aCtx->SetColor(sRGBColor::OpaqueWhite());
nscoord ascent = fm->MaxAscent();
constexpr auto errorMsg = u"invalid-markup"_ns;
nsLayoutUtils::DrawUniDirString(errorMsg.get(), uint32_t(errorMsg.Length()),
nsPoint(pt.x, pt.y + ascent), *fm, *aCtx);
}
/* /////////////
* nsIMathMLFrame - support methods for stretchy elements
* =============================================================================
*/
static bool IsForeignChild(const nsIFrame* aFrame) {
// This counts nsMathMLmathBlockFrame as a foreign child, because it
// uses block reflow
return !(aFrame->IsFrameOfType(nsIFrame::eMathML)) || aFrame->IsBlockFrame();
}
NS_DECLARE_FRAME_PROPERTY_DELETABLE(HTMLReflowOutputProperty, ReflowOutput)
/* static */
void nsMathMLContainerFrame::SaveReflowAndBoundingMetricsFor(
nsIFrame* aFrame, const ReflowOutput& aReflowOutput,
const nsBoundingMetrics& aBoundingMetrics) {
ReflowOutput* reflowOutput = new ReflowOutput(aReflowOutput);
reflowOutput->mBoundingMetrics = aBoundingMetrics;
aFrame->SetProperty(HTMLReflowOutputProperty(), reflowOutput);
}
// helper method to facilitate getting the reflow and bounding metrics
/* static */
void nsMathMLContainerFrame::GetReflowAndBoundingMetricsFor(
nsIFrame* aFrame, ReflowOutput& aReflowOutput,
nsBoundingMetrics& aBoundingMetrics, eMathMLFrameType* aMathMLFrameType) {
MOZ_ASSERT(aFrame, "null arg");
ReflowOutput* reflowOutput = aFrame->GetProperty(HTMLReflowOutputProperty());
// IMPORTANT: This function is only meant to be called in Place() methods
// where it is assumed that SaveReflowAndBoundingMetricsFor has recorded the
// information.
NS_ASSERTION(reflowOutput, "Didn't SaveReflowAndBoundingMetricsFor frame!");
if (reflowOutput) {
aReflowOutput = *reflowOutput;
aBoundingMetrics = reflowOutput->mBoundingMetrics;
}
if (aMathMLFrameType) {
if (!IsForeignChild(aFrame)) {
nsIMathMLFrame* mathMLFrame = do_QueryFrame(aFrame);
if (mathMLFrame) {
*aMathMLFrameType = mathMLFrame->GetMathMLFrameType();
return;
}
}
*aMathMLFrameType = eMathMLFrameType_UNKNOWN;
}
}
void nsMathMLContainerFrame::ClearSavedChildMetrics() {
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
childFrame->RemoveProperty(HTMLReflowOutputProperty());
childFrame = childFrame->GetNextSibling();
}
}
// helper to get the preferred size that a container frame should use to fire
// the stretch on its stretchy child frames.
void nsMathMLContainerFrame::GetPreferredStretchSize(
DrawTarget* aDrawTarget, uint32_t aOptions,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aPreferredStretchSize) {
if (aOptions & STRETCH_CONSIDER_ACTUAL_SIZE) {
// when our actual size is ok, just use it
aPreferredStretchSize = mBoundingMetrics;
} else if (aOptions & STRETCH_CONSIDER_EMBELLISHMENTS) {
// compute our up-to-date size using Place()
ReflowOutput reflowOutput(GetWritingMode());
Place(aDrawTarget, false, reflowOutput);
aPreferredStretchSize = reflowOutput.mBoundingMetrics;
} else {
// compute a size that includes embellishments iff the container stretches
// in the same direction as the embellished operator.
bool stretchAll = aStretchDirection == NS_STRETCH_DIRECTION_VERTICAL
? NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
mPresentationData.flags)
: NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
mPresentationData.flags);
NS_ASSERTION(aStretchDirection == NS_STRETCH_DIRECTION_HORIZONTAL ||
aStretchDirection == NS_STRETCH_DIRECTION_VERTICAL,
"You must specify a direction in which to stretch");
NS_ASSERTION(
NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags) || stretchAll,
"invalid call to GetPreferredStretchSize");
bool firstTime = true;
nsBoundingMetrics bm, bmChild;
nsIFrame* childFrame = stretchAll ? PrincipalChildList().FirstChild()
: mPresentationData.baseFrame;
while (childFrame) {
// initializations in case this child happens not to be a MathML frame
nsIMathMLFrame* mathMLFrame = do_QueryFrame(childFrame);
if (mathMLFrame) {
nsEmbellishData embellishData;
nsPresentationData presentationData;
mathMLFrame->GetEmbellishData(embellishData);
mathMLFrame->GetPresentationData(presentationData);
if (NS_MATHML_IS_EMBELLISH_OPERATOR(embellishData.flags) &&
embellishData.direction == aStretchDirection &&
presentationData.baseFrame) {
// embellishements are not included, only consider the inner first
// child itself
// XXXkt Does that mean the core descendent frame should be used
// instead of the base child?
nsIMathMLFrame* mathMLchildFrame =
do_QueryFrame(presentationData.baseFrame);
if (mathMLchildFrame) {
mathMLFrame = mathMLchildFrame;
}
}
mathMLFrame->GetBoundingMetrics(bmChild);
} else {
ReflowOutput unused(GetWritingMode());
GetReflowAndBoundingMetricsFor(childFrame, unused, bmChild);
}
if (firstTime) {
firstTime = false;
bm = bmChild;
if (!stretchAll) {
// we may get here for cases such as <msup><mo>...</mo> ... </msup>,
// or <maction>...<mo>...</mo></maction>.
break;
}
} else {
if (aStretchDirection == NS_STRETCH_DIRECTION_HORIZONTAL) {
// if we get here, it means this is container that will stack its
// children vertically and fire an horizontal stretch on each them.
// This is the case for \munder, \mover, \munderover. We just sum-up
// the size vertically.
bm.descent += bmChild.ascent + bmChild.descent;
// Sometimes non-spacing marks (when width is zero) are positioned
// to the left of the origin, but it is the distance between left
// and right bearing that is important rather than the offsets from
// the origin.
if (bmChild.width == 0) {
bmChild.rightBearing -= bmChild.leftBearing;
bmChild.leftBearing = 0;
}
if (bm.leftBearing > bmChild.leftBearing)
bm.leftBearing = bmChild.leftBearing;
if (bm.rightBearing < bmChild.rightBearing)
bm.rightBearing = bmChild.rightBearing;
} else if (aStretchDirection == NS_STRETCH_DIRECTION_VERTICAL) {
// just sum-up the sizes horizontally.
bm += bmChild;
} else {
NS_ERROR("unexpected case in GetPreferredStretchSize");
break;
}
}
childFrame = childFrame->GetNextSibling();
}
aPreferredStretchSize = bm;
}
}
NS_IMETHODIMP
nsMathMLContainerFrame::Stretch(DrawTarget* aDrawTarget,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aContainerSize,
ReflowOutput& aDesiredStretchSize) {
if (NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags)) {
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;
if (NS_MATHML_HAS_ERROR(mPresentationData.flags)) {
NS_WARNING("it is wrong to fire stretch on a erroneous frame");
return NS_OK;
}
// Pass the stretch to the base child ...
nsIFrame* baseFrame = mPresentationData.baseFrame;
if (baseFrame) {
nsIMathMLFrame* mathMLFrame = do_QueryFrame(baseFrame);
NS_ASSERTION(mathMLFrame, "Something is wrong somewhere");
if (mathMLFrame) {
// And the trick is that the child's rect.x is still holding the
// descent, and rect.y is still holding the ascent ...
ReflowOutput childSize(aDesiredStretchSize);
GetReflowAndBoundingMetricsFor(baseFrame, childSize,
childSize.mBoundingMetrics);
// See if we should downsize and confine the stretch to us...
// XXX there may be other cases where we can downsize the stretch,
// e.g., the first ∑ might appear big in the following situation
// <math xmlns='http://www.w3.org/1998/Math/MathML'>
// <mstyle>
// <msub>
// <msub><mo>∑</mo><mfrac><mi>a</mi><mi>b</mi></mfrac></msub>
// <msub><mo>∑</mo><mfrac><mi>a</mi><mi>b</mi></mfrac></msub>
// </msub>
// </mstyle>
// </math>
nsBoundingMetrics containerSize = aContainerSize;
if (aStretchDirection != mEmbellishData.direction &&
mEmbellishData.direction != NS_STRETCH_DIRECTION_UNSUPPORTED) {
NS_ASSERTION(
mEmbellishData.direction != NS_STRETCH_DIRECTION_DEFAULT,
"Stretches may have a default direction, operators can not.");
if (mEmbellishData.direction == NS_STRETCH_DIRECTION_VERTICAL
? NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
mPresentationData.flags)
: NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
mPresentationData.flags)) {
GetPreferredStretchSize(aDrawTarget, 0, mEmbellishData.direction,
containerSize);
// Stop further recalculations
aStretchDirection = mEmbellishData.direction;
} else {
// We aren't going to stretch the child, so just use the child
// metrics.
containerSize = childSize.mBoundingMetrics;
}
}
// do the stretching...
mathMLFrame->Stretch(aDrawTarget, aStretchDirection, containerSize,
childSize);
// store the updated metrics
SaveReflowAndBoundingMetricsFor(baseFrame, childSize,
childSize.mBoundingMetrics);
// Remember the siblings which were _deferred_.
// Now that this embellished child may have changed, we need to
// fire the stretch on its siblings using our updated size
if (NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
mPresentationData.flags) ||
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
mPresentationData.flags)) {
nsStretchDirection stretchDir =
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
mPresentationData.flags)
? NS_STRETCH_DIRECTION_VERTICAL
: NS_STRETCH_DIRECTION_HORIZONTAL;
GetPreferredStretchSize(aDrawTarget, STRETCH_CONSIDER_EMBELLISHMENTS,
stretchDir, containerSize);
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
if (childFrame != mPresentationData.baseFrame) {
mathMLFrame = do_QueryFrame(childFrame);
if (mathMLFrame) {
// retrieve the metrics that was stored at the previous pass
GetReflowAndBoundingMetricsFor(childFrame, childSize,
childSize.mBoundingMetrics);
// do the stretching...
mathMLFrame->Stretch(aDrawTarget, stretchDir, containerSize,
childSize);
// store the updated metrics
SaveReflowAndBoundingMetricsFor(childFrame, childSize,
childSize.mBoundingMetrics);
}
}
childFrame = childFrame->GetNextSibling();
}
}
// re-position all our children
nsresult rv = Place(aDrawTarget, 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 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.
nsEmbellishData parentData;
GetEmbellishDataFrom(GetParent(), parentData);
// ensure that we are the embellished child, not just a sibling
// (need to test coreFrame since <mfrac> resets other things)
if (parentData.coreFrame != mEmbellishData.coreFrame) {
// (we fetch values from the core since they may use units that depend
// on style data, and style changes could have occurred in the core
// since our last visit there)
nsEmbellishData coreData;
GetEmbellishDataFrom(mEmbellishData.coreFrame, coreData);
mBoundingMetrics.width +=
coreData.leadingSpace + coreData.trailingSpace;
aDesiredStretchSize.Width() = mBoundingMetrics.width;
aDesiredStretchSize.mBoundingMetrics.width = mBoundingMetrics.width;
nscoord dx = StyleVisibility()->mDirection == StyleDirection::Rtl
? coreData.trailingSpace
: coreData.leadingSpace;
if (dx != 0) {
mBoundingMetrics.leftBearing += dx;
mBoundingMetrics.rightBearing += dx;
aDesiredStretchSize.mBoundingMetrics.leftBearing += dx;
aDesiredStretchSize.mBoundingMetrics.rightBearing += dx;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
childFrame->SetPosition(childFrame->GetPosition() +
nsPoint(dx, 0));
childFrame = childFrame->GetNextSibling();
}
}
}
// Finished with these:
ClearSavedChildMetrics();
// Set our overflow area
GatherAndStoreOverflow(&aDesiredStretchSize);
}
}
}
return NS_OK;
}
nsresult nsMathMLContainerFrame::FinalizeReflow(DrawTarget* aDrawTarget,
ReflowOutput& aDesiredSize) {
// During reflow, we use rect.x and rect.y as placeholders for the child's
// ascent and descent in expectation of a stretch command. Hence we need to
// ensure that a stretch command will actually be fired later on, after
// exiting from our reflow. If the stretch is not fired, the rect.x, and
// rect.y will remain with inappropriate data causing children to be
// improperly positioned. This helper method checks to see if our parent will
// fire a stretch command targeted at us. If not, we go ahead and fire an
// involutive stretch on ourselves. This will clear all the rect.x and rect.y,
// and return our desired size.
// First, complete the post-reflow hook.
// We use the information in our children rectangles to position them.
// If placeOrigin==false, then Place() will not touch rect.x, and rect.y.
// They will still be holding the ascent and descent for each child.
// The first clause caters for any non-embellished container.
// The second clause is for a container which won't fire stretch even though
// it is embellished, e.g., as in <mfrac><mo>...</mo> ... </mfrac>, the test
// is convoluted because it excludes the particular case of the core
// <mo>...</mo> itself.
// (<mo> needs to fire stretch on its MathMLChar in any case to initialize it)
bool placeOrigin =
!NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags) ||
(mEmbellishData.coreFrame != this && !mPresentationData.baseFrame &&
mEmbellishData.direction == NS_STRETCH_DIRECTION_UNSUPPORTED);
nsresult rv = Place(aDrawTarget, placeOrigin, aDesiredSize);
// Place() will call FinishReflowChild() when placeOrigin is true but if
// it returns before reaching FinishReflowChild() due to errors we need
// to fulfill the reflow protocol by calling DidReflow for the child frames
// that still needs it here (or we may crash - bug 366012).
// If placeOrigin is false we should reach Place() with aPlaceOrigin == true
// through Stretch() eventually.
if (NS_MATHML_HAS_ERROR(mPresentationData.flags) || NS_FAILED(rv)) {
GatherAndStoreOverflow(&aDesiredSize);
DidReflowChildren(PrincipalChildList().FirstChild());
return rv;
}
bool parentWillFireStretch = false;
if (!placeOrigin) {
// This means the rect.x and rect.y of our children were not set!!
// Don't go without checking to see if our parent will later fire a
// Stretch() command targeted at us. The Stretch() will cause the rect.x and
// rect.y to clear...
nsIMathMLFrame* mathMLFrame = do_QueryFrame(GetParent());
if (mathMLFrame) {
nsEmbellishData embellishData;
nsPresentationData presentationData;
mathMLFrame->GetEmbellishData(embellishData);
mathMLFrame->GetPresentationData(presentationData);
if (NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
presentationData.flags) ||
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
presentationData.flags) ||
(NS_MATHML_IS_EMBELLISH_OPERATOR(embellishData.flags) &&
presentationData.baseFrame == this)) {
parentWillFireStretch = true;
}
}
if (!parentWillFireStretch) {
// There is nobody who will fire the stretch for us, we do it ourselves!
bool stretchAll =
/* NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(mPresentationData.flags)
|| */
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
mPresentationData.flags);
nsStretchDirection stretchDir;
if (mEmbellishData.coreFrame ==
this || /* case of a bare <mo>...</mo> itself */
(mEmbellishData.direction == NS_STRETCH_DIRECTION_HORIZONTAL &&
stretchAll) || /* or <mover><mo>...</mo>...</mover>, or friends */
mEmbellishData.direction ==
NS_STRETCH_DIRECTION_UNSUPPORTED) { /* Doesn't stretch */
stretchDir = mEmbellishData.direction;
} else {
// Let the Stretch() call decide the direction.
stretchDir = NS_STRETCH_DIRECTION_DEFAULT;
}
// Use our current size as computed earlier by Place()
// The stretch call will detect if this is incorrect and recalculate the
// size.
nsBoundingMetrics defaultSize = aDesiredSize.mBoundingMetrics;
Stretch(aDrawTarget, stretchDir, defaultSize, aDesiredSize);
#ifdef DEBUG
{
// The Place() call above didn't request FinishReflowChild(),
// so let's check that we eventually did through Stretch().
for (nsIFrame* childFrame : PrincipalChildList()) {
NS_ASSERTION(!childFrame->HasAnyStateBits(NS_FRAME_IN_REFLOW),
"DidReflow() was never called");
}
}
#endif
}
}
// Also return our bounding metrics
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
// see if we should fix the spacing
FixInterFrameSpacing(aDesiredSize);
if (!parentWillFireStretch) {
// Not expecting a stretch.
// Finished with these:
ClearSavedChildMetrics();
// Set our overflow area.
GatherAndStoreOverflow(&aDesiredSize);
}
return NS_OK;
}
/* /////////////
* nsIMathMLFrame - support methods for scripting elements (nested frames
* within msub, msup, msubsup, munder, mover, munderover, mmultiscripts,
* mfrac, mroot, mtable).
* =============================================================================
*/
// helper to let the update of presentation data pass through
// a subtree that may contain non-mathml container frames
/* static */
void nsMathMLContainerFrame::PropagatePresentationDataFor(
nsIFrame* aFrame, uint32_t aFlagsValues, uint32_t aFlagsToUpdate) {
if (!aFrame || !aFlagsToUpdate) return;
nsIMathMLFrame* mathMLFrame = do_QueryFrame(aFrame);
if (mathMLFrame) {
// update
mathMLFrame->UpdatePresentationData(aFlagsValues, aFlagsToUpdate);
// propagate using the base method to make sure that the control
// is passed on to MathML frames that may be overloading the method
mathMLFrame->UpdatePresentationDataFromChildAt(0, -1, aFlagsValues,
aFlagsToUpdate);
} else {
// propagate down the subtrees
for (nsIFrame* childFrame : aFrame->PrincipalChildList()) {
PropagatePresentationDataFor(childFrame, aFlagsValues, aFlagsToUpdate);
}
}
}
/* static */
void nsMathMLContainerFrame::PropagatePresentationDataFromChildAt(
nsIFrame* aParentFrame, int32_t aFirstChildIndex, int32_t aLastChildIndex,
uint32_t aFlagsValues, uint32_t aFlagsToUpdate) {
if (!aParentFrame || !aFlagsToUpdate) return;
int32_t index = 0;
for (nsIFrame* childFrame : aParentFrame->PrincipalChildList()) {
if ((index >= aFirstChildIndex) &&
((aLastChildIndex <= 0) ||
((aLastChildIndex > 0) && (index <= aLastChildIndex)))) {
PropagatePresentationDataFor(childFrame, aFlagsValues, aFlagsToUpdate);
}
index++;
}
}
/* //////////////////
* Frame construction
* =============================================================================
*/
void nsMathMLContainerFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) {
// report an error if something wrong was found in this frame
if (NS_MATHML_HAS_ERROR(mPresentationData.flags)) {
if (!IsVisibleForPainting()) return;
aLists.Content()->AppendNewToTop<nsDisplayMathMLError>(aBuilder, this);
return;
}
BuildDisplayListForInline(aBuilder, aLists);
#if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
// for visual debug
// ----------------
// if you want to see your bounding box, make sure to properly fill
// your mBoundingMetrics and mReference point, and set
// mPresentationData.flags |= NS_MATHML_SHOW_BOUNDING_METRICS
// in the Init() of your sub-class
DisplayBoundingMetrics(aBuilder, this, mReference, mBoundingMetrics, aLists);
#endif
}
// 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()).
/* static */
void nsMathMLContainerFrame::RebuildAutomaticDataForChildren(
nsIFrame* aParentFrame) {
// 1. As we descend the tree, make each child frame inherit data from
// the parent
// 2. As we ascend the tree, transmit any specific change that we want
// down the subtrees
for (nsIFrame* childFrame : aParentFrame->PrincipalChildList()) {
nsIMathMLFrame* childMathMLFrame = do_QueryFrame(childFrame);
if (childMathMLFrame) {
childMathMLFrame->InheritAutomaticData(aParentFrame);
}
RebuildAutomaticDataForChildren(childFrame);
}
nsIMathMLFrame* mathMLFrame = do_QueryFrame(aParentFrame);
if (mathMLFrame) {
mathMLFrame->TransmitAutomaticData();
}
}
/* static */
nsresult nsMathMLContainerFrame::ReLayoutChildren(nsIFrame* aParentFrame) {
if (!aParentFrame) return NS_OK;
// walk-up to the first frame that is a MathML frame, stop if we reach <math>
nsIFrame* frame = aParentFrame;
while (1) {
nsIFrame* parent = frame->GetParent();
if (!parent || !parent->GetContent()) break;
// stop if it is a MathML frame
nsIMathMLFrame* mathMLFrame = do_QueryFrame(frame);
if (mathMLFrame) break;
// stop if we reach the root <math> tag
nsIContent* content = frame->GetContent();
NS_ASSERTION(content, "dangling frame without a content node");
if (!content) break;
if (content->IsMathMLElement(nsGkAtoms::math)) break;
frame = parent;
}
// re-sync the presentation data and embellishment data of our children
RebuildAutomaticDataForChildren(frame);
// Ask our parent frame to reflow us
nsIFrame* parent = frame->GetParent();
NS_ASSERTION(parent, "No parent to pass the reflow request up to");
if (!parent) return NS_OK;
frame->PresShell()->FrameNeedsReflow(frame, IntrinsicDirty::StyleChange,
NS_FRAME_IS_DIRTY);
return NS_OK;
}
// There are precise rules governing children of a MathML frame,
// and properties such as the scriptlevel depends on those rules.
// Hence for things to work, callers must use Append/Insert/etc wisely.
nsresult nsMathMLContainerFrame::ChildListChanged(int32_t aModType) {
// If this is an embellished frame we need to rebuild the
// embellished hierarchy by walking-up to the parent of the
// outermost embellished container.
nsIFrame* frame = this;
if (mEmbellishData.coreFrame) {
nsIFrame* parent = GetParent();
nsEmbellishData embellishData;
for (; parent; frame = parent, parent = parent->GetParent()) {
GetEmbellishDataFrom(parent, embellishData);
if (embellishData.coreFrame != mEmbellishData.coreFrame) break;
}
}
return ReLayoutChildren(frame);
}
void nsMathMLContainerFrame::AppendFrames(ChildListID aListID,
nsFrameList& aFrameList) {
MOZ_ASSERT(aListID == kPrincipalList);
mFrames.AppendFrames(this, aFrameList);
ChildListChanged(dom::MutationEvent_Binding::ADDITION);
}
void nsMathMLContainerFrame::InsertFrames(
ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine, nsFrameList& aFrameList) {
MOZ_ASSERT(aListID == kPrincipalList);
mFrames.InsertFrames(this, aPrevFrame, aFrameList);
ChildListChanged(dom::MutationEvent_Binding::ADDITION);
}
void nsMathMLContainerFrame::RemoveFrame(ChildListID aListID,
nsIFrame* aOldFrame) {
MOZ_ASSERT(aListID == kPrincipalList);
mFrames.DestroyFrame(aOldFrame);
ChildListChanged(dom::MutationEvent_Binding::REMOVAL);
}
nsresult nsMathMLContainerFrame::AttributeChanged(int32_t aNameSpaceID,
nsAtom* aAttribute,
int32_t aModType) {
// XXX Since they are numerous MathML attributes that affect layout, and
// we can't check all of them here, play safe by requesting a reflow.
// XXXldb This should only do work for attributes that cause changes!
PresShell()->FrameNeedsReflow(this, IntrinsicDirty::StyleChange,
NS_FRAME_IS_DIRTY);
return NS_OK;
}
void nsMathMLContainerFrame::GatherAndStoreOverflow(ReflowOutput* aMetrics) {
mBlockStartAscent = aMetrics->BlockStartAscent();
// nsIFrame::FinishAndStoreOverflow likes the overflow area to include the
// frame rectangle.
aMetrics->SetOverflowAreasToDesiredBounds();
ComputeCustomOverflow(aMetrics->mOverflowAreas);
// mBoundingMetrics does not necessarily include content of <mpadded>
// elements whose mBoundingMetrics may not be representative of the true
// bounds, and doesn't include the CSS2 outline rectangles of children, so
// make such to include child overflow areas.
UnionChildOverflow(aMetrics->mOverflowAreas);
FinishAndStoreOverflow(aMetrics);
}
bool nsMathMLContainerFrame::ComputeCustomOverflow(
OverflowAreas& aOverflowAreas) {
// All non-child-frame content such as nsMathMLChars (and most child-frame
// content) is included in mBoundingMetrics.
nsRect boundingBox(
mBoundingMetrics.leftBearing, mBlockStartAscent - mBoundingMetrics.ascent,
mBoundingMetrics.rightBearing - mBoundingMetrics.leftBearing,
mBoundingMetrics.ascent + mBoundingMetrics.descent);
// REVIEW: Maybe this should contribute only to ink overflow
// and not scrollable?
aOverflowAreas.UnionAllWith(boundingBox);
return nsContainerFrame::ComputeCustomOverflow(aOverflowAreas);
}
void nsMathMLContainerFrame::ReflowChild(nsIFrame* aChildFrame,
nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) {
// Having foreign/hybrid children, e.g., from html markups, is not defined by
// the MathML spec. But it can happen in practice, e.g., <html:img> allows us
// to do some cool demos... or we may have a child that is an nsInlineFrame
// from a generated content such as :before { content: open-quote } or
// :after { content: close-quote }. Unfortunately, the other frames out-there
// may expect their own invariants that are not met when we mix things.
// Hence we do not claim their support, but we will nevertheless attempt to
// keep them in the flow, if we can get their desired size. We observed that
// most frames may be reflowed generically, but nsInlineFrames need extra
// care.
#ifdef DEBUG
nsInlineFrame* inlineFrame = do_QueryFrame(aChildFrame);
NS_ASSERTION(!inlineFrame, "Inline frames should be wrapped in blocks");
#endif
nsContainerFrame::ReflowChild(aChildFrame, aPresContext, aDesiredSize,
aReflowInput, 0, 0,
ReflowChildFlags::NoMoveFrame, aStatus);
if (aDesiredSize.BlockStartAscent() == ReflowOutput::ASK_FOR_BASELINE) {
// This will be suitable for inline frames, which are wrapped in a block.
nscoord ascent;
WritingMode wm = aDesiredSize.GetWritingMode();
if (!nsLayoutUtils::GetLastLineBaseline(wm, aChildFrame, &ascent)) {
// We don't expect any other block children so just place the frame on
// the baseline instead of going through DidReflow() and
// GetBaseline(). This is what nsIFrame::GetBaseline() will do anyway.
aDesiredSize.SetBlockStartAscent(aDesiredSize.BSize(wm));
} else {
aDesiredSize.SetBlockStartAscent(ascent);
}
}
if (IsForeignChild(aChildFrame)) {
// use ComputeTightBounds API as aDesiredSize.mBoundingMetrics is not set.
nsRect r = aChildFrame->ComputeTightBounds(
aReflowInput.mRenderingContext->GetDrawTarget());
aDesiredSize.mBoundingMetrics.leftBearing = r.x;
aDesiredSize.mBoundingMetrics.rightBearing = r.XMost();
aDesiredSize.mBoundingMetrics.ascent =
aDesiredSize.BlockStartAscent() - r.y;
aDesiredSize.mBoundingMetrics.descent =
r.YMost() - aDesiredSize.BlockStartAscent();
aDesiredSize.mBoundingMetrics.width = aDesiredSize.Width();
}
}
void nsMathMLContainerFrame::Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) {
MarkInReflow();
MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
mPresentationData.flags &= ~NS_MATHML_ERROR;
aDesiredSize.Width() = aDesiredSize.Height() = 0;
aDesiredSize.SetBlockStartAscent(0);
aDesiredSize.mBoundingMetrics = nsBoundingMetrics();
/////////////
// Reflow children
// Asking each child to cache its bounding metrics
nsReflowStatus childStatus;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
ReflowOutput childDesiredSize(aReflowInput);
WritingMode wm = childFrame->GetWritingMode();
LogicalSize availSize = aReflowInput.ComputedSize(wm);
availSize.BSize(wm) = NS_UNCONSTRAINEDSIZE;
ReflowInput childReflowInput(aPresContext, aReflowInput, childFrame,
availSize);
ReflowChild(childFrame, aPresContext, childDesiredSize, childReflowInput,
childStatus);
// NS_ASSERTION(childStatus.IsComplete(), "bad status");
SaveReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
childFrame = childFrame->GetNextSibling();
}
/////////////
// If we are a container which is entitled to stretch its children, then we
// ask our stretchy children to stretch themselves
// The stretching of siblings of an embellished child is _deferred_ until
// after finishing the stretching of the embellished child - bug 117652
DrawTarget* drawTarget = aReflowInput.mRenderingContext->GetDrawTarget();
if (!NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags) &&
(NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(
mPresentationData.flags) ||
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(
mPresentationData.flags))) {
// get the stretchy direction
nsStretchDirection stretchDir =
NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(mPresentationData.flags)
? NS_STRETCH_DIRECTION_VERTICAL
: NS_STRETCH_DIRECTION_HORIZONTAL;
// what size should we use to stretch our stretchy children
// We don't use STRETCH_CONSIDER_ACTUAL_SIZE -- because our size is not
// known yet We don't use STRETCH_CONSIDER_EMBELLISHMENTS -- because we
// don't want to include them in the caculations of the size of stretchy
// elements
nsBoundingMetrics containerSize;
GetPreferredStretchSize(drawTarget, 0, stretchDir, containerSize);
// fire the stretch on each child
childFrame = mFrames.FirstChild();
while (childFrame) {
nsIMathMLFrame* mathMLFrame = do_QueryFrame(childFrame);
if (mathMLFrame) {
// retrieve the metrics that was stored at the previous pass
ReflowOutput childDesiredSize(aReflowInput);
GetReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
mathMLFrame->Stretch(drawTarget, stretchDir, containerSize,
childDesiredSize);
// store the updated metrics
SaveReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
}
childFrame = childFrame->GetNextSibling();
}
}
/////////////
// Place children now by re-adjusting the origins to align the baselines
FinalizeReflow(drawTarget, aDesiredSize);
NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
}
static nscoord AddInterFrameSpacingToSize(ReflowOutput& aDesiredSize,
nsMathMLContainerFrame* aFrame);
/* virtual */
void nsMathMLContainerFrame::MarkIntrinsicISizesDirty() {
mIntrinsicWidth = NS_INTRINSIC_ISIZE_UNKNOWN;
nsContainerFrame::MarkIntrinsicISizesDirty();
}
void nsMathMLContainerFrame::UpdateIntrinsicWidth(
gfxContext* aRenderingContext) {
if (mIntrinsicWidth == NS_INTRINSIC_ISIZE_UNKNOWN) {
ReflowOutput desiredSize(GetWritingMode());
GetIntrinsicISizeMetrics(aRenderingContext, desiredSize);
// Include the additional width added by FixInterFrameSpacing to ensure
// consistent width calculations.
AddInterFrameSpacingToSize(desiredSize, this);
mIntrinsicWidth = desiredSize.ISize(GetWritingMode());
}
}
/* virtual */
nscoord nsMathMLContainerFrame::GetMinISize(gfxContext* aRenderingContext) {
nscoord result;
DISPLAY_MIN_INLINE_SIZE(this, result);
UpdateIntrinsicWidth(aRenderingContext);
result = mIntrinsicWidth;
return result;
}
/* virtual */
nscoord nsMathMLContainerFrame::GetPrefISize(gfxContext* aRenderingContext) {
nscoord result;
DISPLAY_PREF_INLINE_SIZE(this, result);
UpdateIntrinsicWidth(aRenderingContext);
result = mIntrinsicWidth;
return result;
}
/* virtual */
void nsMathMLContainerFrame::GetIntrinsicISizeMetrics(
gfxContext* aRenderingContext, ReflowOutput& aDesiredSize) {
// Get child widths
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
ReflowOutput childDesiredSize(GetWritingMode()); // ???
nsMathMLContainerFrame* containerFrame = do_QueryFrame(childFrame);
if (containerFrame) {
containerFrame->GetIntrinsicISizeMetrics(aRenderingContext,
childDesiredSize);
} else {
// XXX This includes margin while Reflow currently doesn't consider
// margin, so we may end up with too much space, but, with stretchy
// characters, this is an approximation anyway.
nscoord width = nsLayoutUtils::IntrinsicForContainer(
aRenderingContext, childFrame, IntrinsicISizeType::PrefISize);
childDesiredSize.Width() = width;
childDesiredSize.mBoundingMetrics.width = width;
childDesiredSize.mBoundingMetrics.leftBearing = 0;
childDesiredSize.mBoundingMetrics.rightBearing = width;
nscoord x, xMost;
if (NS_SUCCEEDED(childFrame->GetPrefWidthTightBounds(aRenderingContext,
&x, &xMost))) {
childDesiredSize.mBoundingMetrics.leftBearing = x;
childDesiredSize.mBoundingMetrics.rightBearing = xMost;
}
}
SaveReflowAndBoundingMetricsFor(childFrame, childDesiredSize,
childDesiredSize.mBoundingMetrics);
childFrame = childFrame->GetNextSibling();
}
// Measure
nsresult rv =
MeasureForWidth(aRenderingContext->GetDrawTarget(), aDesiredSize);
if (NS_FAILED(rv)) {
ReflowError(aRenderingContext->GetDrawTarget(), aDesiredSize);
}
ClearSavedChildMetrics();
}
/* virtual */
nsresult nsMathMLContainerFrame::MeasureForWidth(DrawTarget* aDrawTarget,
ReflowOutput& aDesiredSize) {
return Place(aDrawTarget, false, aDesiredSize);
}
// see spacing table in Chapter 18, TeXBook (p.170)
// Our table isn't quite identical to TeX because operators have
// built-in values for lspace & rspace in the Operator Dictionary.
static int32_t
kInterFrameSpacingTable[eMathMLFrameType_COUNT][eMathMLFrameType_COUNT] = {
// in units of muspace.
// upper half of the byte is set if the
// spacing is not to be used for scriptlevel > 0
/* Ord OpOrd OpInv OpUsr Inner Italic Upright */
/*Ord */ {0x00, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00},
/*OpOrd */ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
/*OpInv */ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
/*OpUsr */ {0x01, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01},
/*Inner */ {0x01, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01},
/*Italic */ {0x00, 0x00, 0x00, 0x01, 0x01, 0x00, 0x01},
/*Upright*/ {0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x00}};
#define GET_INTERSPACE(scriptlevel_, frametype1_, frametype2_, space_) \
/* no space if there is a frame that we know nothing about */ \
if (frametype1_ == eMathMLFrameType_UNKNOWN || \
frametype2_ == eMathMLFrameType_UNKNOWN) \
space_ = 0; \
else { \
space_ = kInterFrameSpacingTable[frametype1_][frametype2_]; \
space_ = (scriptlevel_ > 0 && (space_ & 0xF0)) \
? 0 /* spacing is disabled */ \
: space_ & 0x0F; \
}
// This function computes the inter-space between two frames. However,
// since invisible operators need special treatment, the inter-space may
// be delayed when an invisible operator is encountered. In this case,
// the function will carry the inter-space forward until it is determined
// that it can be applied properly (i.e., until we encounter a visible
// frame where to decide whether to accept or reject the inter-space).
// aFromFrameType: remembers the frame when the carry-forward initiated.
// aCarrySpace: keeps track of the inter-space that is delayed.
// @returns: current inter-space (which is 0 when the true inter-space is
// delayed -- and thus has no effect since the frame is invisible anyway).
static nscoord GetInterFrameSpacing(int32_t aScriptLevel,
eMathMLFrameType aFirstFrameType,
eMathMLFrameType aSecondFrameType,
eMathMLFrameType* aFromFrameType, // IN/OUT
int32_t* aCarrySpace) // IN/OUT
{
eMathMLFrameType firstType = aFirstFrameType;
eMathMLFrameType secondType = aSecondFrameType;
int32_t space;
GET_INTERSPACE(aScriptLevel, firstType, secondType, space);
// feedback control to avoid the inter-space to be added when not necessary
if (secondType == eMathMLFrameType_OperatorInvisible) {
// see if we should start to carry the space forward until we
// encounter a visible frame
if (*aFromFrameType == eMathMLFrameType_UNKNOWN) {
*aFromFrameType = firstType;
*aCarrySpace = space;
}
// keep carrying *aCarrySpace forward, while returning 0 for this stage
space = 0;
} else if (*aFromFrameType != eMathMLFrameType_UNKNOWN) {
// no carry-forward anymore, get the real inter-space between
// the two frames of interest
firstType = *aFromFrameType;
// But... the invisible operator that we encountered earlier could
// be sitting between italic and upright identifiers, e.g.,
//
// 1. <mi>sin</mi> <mo>⁡</mo> <mi>x</mi>
// 2. <mi>x</mi> <mo>&InvisibileTime;</mo> <mi>sin</mi>
//
// the trick to get the inter-space in either situation
// is to promote "<mi>sin</mi><mo>⁡</mo>" and
// "<mo>&InvisibileTime;</mo><mi>sin</mi>" to user-defined operators...
if (firstType == eMathMLFrameType_UprightIdentifier) {
firstType = eMathMLFrameType_OperatorUserDefined;
} else if (secondType == eMathMLFrameType_UprightIdentifier) {
secondType = eMathMLFrameType_OperatorUserDefined;
}
GET_INTERSPACE(aScriptLevel, firstType, secondType, space);
// Now, we have two values: the computed space and the space that
// has been carried forward until now. Which value do we pick?
// If the second type is an operator (e.g., fence), it already has
// built-in lspace & rspace, so we let them win. Otherwise we pick
// the max between the two values that we have.
if (secondType != eMathMLFrameType_OperatorOrdinary && space < *aCarrySpace)
space = *aCarrySpace;
// reset everything now that the carry-forward is done
*aFromFrameType = eMathMLFrameType_UNKNOWN;
*aCarrySpace = 0;
}
return space;
}
static nscoord GetThinSpace(const nsStyleFont* aStyleFont) {
return aStyleFont->mFont.size.ScaledBy(3.0f / 18.0f).ToAppUnits();
}
class nsMathMLContainerFrame::RowChildFrameIterator {
public:
explicit RowChildFrameIterator(nsMathMLContainerFrame* aParentFrame)
: mParentFrame(aParentFrame),
mReflowOutput(aParentFrame->GetWritingMode()),
mX(0),
mChildFrameType(eMathMLFrameType_UNKNOWN),
mCarrySpace(0),
mFromFrameType(eMathMLFrameType_UNKNOWN),
mRTL(aParentFrame->StyleVisibility()->mDirection ==
StyleDirection::Rtl) {
if (!mRTL) {
mChildFrame = aParentFrame->mFrames.FirstChild();
} else {
mChildFrame = aParentFrame->mFrames.LastChild();
}
if (!mChildFrame) return;
InitMetricsForChild();
}
RowChildFrameIterator& operator++() {
// add child size + italic correction
mX += mReflowOutput.mBoundingMetrics.width + mItalicCorrection;
if (!mRTL) {
mChildFrame = mChildFrame->GetNextSibling();
} else {
mChildFrame = mChildFrame->GetPrevSibling();
}
if (!mChildFrame) return *this;
eMathMLFrameType prevFrameType = mChildFrameType;
InitMetricsForChild();
// add inter frame spacing
const nsStyleFont* font = mParentFrame->StyleFont();
nscoord space =
GetInterFrameSpacing(font->mMathDepth, prevFrameType, mChildFrameType,
&mFromFrameType, &mCarrySpace);
mX += space * GetThinSpace(font);
return *this;
}
nsIFrame* Frame() const { return mChildFrame; }
nscoord X() const { return mX; }
const ReflowOutput& GetReflowOutput() const { return mReflowOutput; }
nscoord Ascent() const { return mReflowOutput.BlockStartAscent(); }
nscoord Descent() const {
return mReflowOutput.Height() - mReflowOutput.BlockStartAscent();
}
const nsBoundingMetrics& BoundingMetrics() const {
return mReflowOutput.mBoundingMetrics;
}
private:
const nsMathMLContainerFrame* mParentFrame;
nsIFrame* mChildFrame;
ReflowOutput mReflowOutput;
nscoord mX;
nscoord mItalicCorrection;
eMathMLFrameType mChildFrameType;
int32_t mCarrySpace;
eMathMLFrameType mFromFrameType;
bool mRTL;
void InitMetricsForChild() {
GetReflowAndBoundingMetricsFor(mChildFrame, mReflowOutput,
mReflowOutput.mBoundingMetrics,
&mChildFrameType);
nscoord leftCorrection, rightCorrection;
GetItalicCorrection(mReflowOutput.mBoundingMetrics, leftCorrection,
rightCorrection);
if (!mChildFrame->GetPrevSibling() &&
mParentFrame->GetContent()->IsMathMLElement(nsGkAtoms::msqrt_)) {
// Remove leading correction in <msqrt> because the sqrt glyph itself is
// there first.
if (!mRTL) {
leftCorrection = 0;
} else {
rightCorrection = 0;
}
}
// add left correction -- this fixes the problem of the italic 'f'
// e.g., <mo>q</mo> <mi>f</mi> <mo>I</mo>
mX += leftCorrection;
mItalicCorrection = rightCorrection;
}
};
/* virtual */
nsresult nsMathMLContainerFrame::Place(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize) {
// This is needed in case this frame is empty (i.e., no child frames)
mBoundingMetrics = nsBoundingMetrics();
RowChildFrameIterator child(this);
nscoord ascent = 0, descent = 0;
while (child.Frame()) {
if (descent < child.Descent()) descent = child.Descent();
if (ascent < child.Ascent()) ascent = child.Ascent();
// add the child size
mBoundingMetrics.width = child.X();
mBoundingMetrics += child.BoundingMetrics();
++child;
}
// Add the italic correction at the end (including the last child).
// This gives a nice gap between math and non-math frames, and still
// gives the same math inter-spacing in case this frame connects to
// another math frame
mBoundingMetrics.width = child.X();
aDesiredSize.Width() = std::max(0, mBoundingMetrics.width);
aDesiredSize.Height() = ascent + descent;
aDesiredSize.SetBlockStartAscent(ascent);
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
//////////////////
// Place Children
if (aPlaceOrigin) {
PositionRowChildFrames(0, aDesiredSize.BlockStartAscent());
}
return NS_OK;
}
void nsMathMLContainerFrame::PositionRowChildFrames(nscoord aOffsetX,
nscoord aBaseline) {
RowChildFrameIterator child(this);
while (child.Frame()) {
nscoord dx = aOffsetX + child.X();
nscoord dy = aBaseline - child.Ascent();
FinishReflowChild(child.Frame(), PresContext(), child.GetReflowOutput(),
nullptr, dx, dy, ReflowChildFlags::Default);
++child;
}
}
// helpers to fix the inter-spacing when <math> is the only parent
// e.g., it fixes <math> <mi>f</mi> <mo>q</mo> <mi>f</mi> <mo>I</mo> </math>
static nscoord GetInterFrameSpacingFor(int32_t aScriptLevel,
nsIFrame* aParentFrame,
nsIFrame* aChildFrame) {
nsIFrame* childFrame = aParentFrame->PrincipalChildList().FirstChild();
if (!childFrame || aChildFrame == childFrame) return 0;
int32_t carrySpace = 0;
eMathMLFrameType fromFrameType = eMathMLFrameType_UNKNOWN;
eMathMLFrameType prevFrameType = eMathMLFrameType_UNKNOWN;
eMathMLFrameType childFrameType =
nsMathMLFrame::GetMathMLFrameTypeFor(childFrame);
childFrame = childFrame->GetNextSibling();
while (childFrame) {
prevFrameType = childFrameType;
childFrameType = nsMathMLFrame::GetMathMLFrameTypeFor(childFrame);
nscoord space =
GetInterFrameSpacing(aScriptLevel, prevFrameType, childFrameType,
&fromFrameType, &carrySpace);
if (aChildFrame == childFrame) {
// get thinspace
ComputedStyle* parentContext = aParentFrame->Style();
nscoord thinSpace = GetThinSpace(parentContext->StyleFont());
// we are done
return space * thinSpace;
}
childFrame = childFrame->GetNextSibling();
}
MOZ_ASSERT_UNREACHABLE("child not in the childlist of its parent");
return 0;
}
static nscoord AddInterFrameSpacingToSize(ReflowOutput& aDesiredSize,
nsMathMLContainerFrame* aFrame) {
nscoord gap = 0;
nsIFrame* parent = aFrame->GetParent();
nsIContent* parentContent = parent->GetContent();
if (MOZ_UNLIKELY(!parentContent)) {
return 0;
}
if (parentContent->IsAnyOfMathMLElements(nsGkAtoms::math, nsGkAtoms::mtd_)) {
gap = GetInterFrameSpacingFor(aFrame->StyleFont()->mMathDepth, parent,
aFrame);
// add our own italic correction
nscoord leftCorrection = 0, italicCorrection = 0;
nsMathMLContainerFrame::GetItalicCorrection(
aDesiredSize.mBoundingMetrics, leftCorrection, italicCorrection);
gap += leftCorrection;
if (gap) {
aDesiredSize.mBoundingMetrics.leftBearing += gap;
aDesiredSize.mBoundingMetrics.rightBearing += gap;
aDesiredSize.mBoundingMetrics.width += gap;
aDesiredSize.Width() += gap;
}
aDesiredSize.mBoundingMetrics.width += italicCorrection;
aDesiredSize.Width() += italicCorrection;
}
return gap;
}
nscoord nsMathMLContainerFrame::FixInterFrameSpacing(
ReflowOutput& aDesiredSize) {
nscoord gap = 0;
gap = AddInterFrameSpacingToSize(aDesiredSize, this);
if (gap) {
// Shift our children to account for the correction
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
childFrame->SetPosition(childFrame->GetPosition() + nsPoint(gap, 0));
childFrame = childFrame->GetNextSibling();
}
}
return gap;
}
/* static */
void nsMathMLContainerFrame::DidReflowChildren(nsIFrame* aFirst,
nsIFrame* aStop)
{
if (MOZ_UNLIKELY(!aFirst)) return;
for (nsIFrame* frame = aFirst; frame != aStop;
frame = frame->GetNextSibling()) {
NS_ASSERTION(frame, "aStop isn't a sibling");
if (frame->HasAnyStateBits(NS_FRAME_IN_REFLOW)) {
// finish off principal descendants, too
nsIFrame* grandchild = frame->PrincipalChildList().FirstChild();
if (grandchild) DidReflowChildren(grandchild, nullptr);
frame->DidReflow(frame->PresContext(), nullptr);
}
}
}
// helper used by mstyle, mphantom, mpadded and mrow in their implementations
// of TransmitAutomaticData().
nsresult nsMathMLContainerFrame::TransmitAutomaticDataForMrowLikeElement() {
//
// One loop to check both conditions below:
//
// 1) whether all the children of the mrow-like element are space-like.
//
// The REC defines the following elements to be "space-like":
// * an mstyle, mphantom, or mpadded element, all of whose direct
// sub-expressions are space-like;
// * an mrow all of whose direct sub-expressions are space-like.
//
// 2) whether all but one child of the mrow-like element are space-like and
// this non-space-like child is an embellished operator.
//
// The REC defines the following elements to be embellished operators:
// * one of the elements mstyle, mphantom, or mpadded, such that an mrow
// containing the same arguments would be an embellished operator;
// * an mrow whose arguments consist (in any order) of one embellished
// operator and zero or more space-like elements.
//
nsIFrame *childFrame, *baseFrame;
bool embellishedOpFound = false;
nsEmbellishData embellishData;
for (childFrame = PrincipalChildList().FirstChild(); childFrame;
childFrame = childFrame->GetNextSibling()) {
nsIMathMLFrame* mathMLFrame = do_QueryFrame(childFrame);
if (!mathMLFrame) break;
if (!mathMLFrame->IsSpaceLike()) {
if (embellishedOpFound) break;
baseFrame = childFrame;
GetEmbellishDataFrom(baseFrame, embellishData);
if (!NS_MATHML_IS_EMBELLISH_OPERATOR(embellishData.flags)) break;
embellishedOpFound = true;
}
}
if (!childFrame) {
// we successfully went to the end of the loop. This means that one of
// condition 1) or 2) holds.
if (!embellishedOpFound) {
// the mrow-like element is space-like.
mPresentationData.flags |= NS_MATHML_SPACE_LIKE;
} else {
// the mrow-like element is an embellished operator.
// let the state of the embellished operator found bubble to us.
mPresentationData.baseFrame = baseFrame;
mEmbellishData = embellishData;
}
}
if (childFrame || !embellishedOpFound) {
// The element is not embellished operator
mPresentationData.baseFrame = nullptr;
mEmbellishData.flags = 0;
mEmbellishData.coreFrame = nullptr;
mEmbellishData.direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
mEmbellishData.leadingSpace = 0;
mEmbellishData.trailingSpace = 0;
}
if (childFrame || embellishedOpFound) {
// The element is not space-like
mPresentationData.flags &= ~NS_MATHML_SPACE_LIKE;
}
return NS_OK;
}
/*static*/
void nsMathMLContainerFrame::PropagateFrameFlagFor(nsIFrame* aFrame,
nsFrameState aFlags) {
if (!aFrame || !aFlags) return;
aFrame->AddStateBits(aFlags);
for (nsIFrame* childFrame : aFrame->PrincipalChildList()) {
PropagateFrameFlagFor(childFrame, aFlags);
}
}
nsresult nsMathMLContainerFrame::ReportErrorToConsole(
const char* errorMsgId, const nsTArray<nsString>& aParams) {
return nsContentUtils::ReportToConsole(
nsIScriptError::errorFlag, "Layout: MathML"_ns, mContent->OwnerDoc(),
nsContentUtils::eMATHML_PROPERTIES, errorMsgId, aParams);
}
nsresult nsMathMLContainerFrame::ReportParseError(const char16_t* aAttribute,
const char16_t* aValue) {
AutoTArray<nsString, 3> argv;
argv.AppendElement(aValue);
argv.AppendElement(aAttribute);
argv.AppendElement(nsDependentAtomString(mContent->NodeInfo()->NameAtom()));
return ReportErrorToConsole("AttributeParsingError", argv);
}
nsresult nsMathMLContainerFrame::ReportChildCountError() {
AutoTArray<nsString, 1> arg = {
nsDependentAtomString(mContent->NodeInfo()->NameAtom())};
return ReportErrorToConsole("ChildCountIncorrect", arg);
}
nsresult nsMathMLContainerFrame::ReportInvalidChildError(nsAtom* aChildTag) {
AutoTArray<nsString, 2> argv = {
nsDependentAtomString(aChildTag),
nsDependentAtomString(mContent->NodeInfo()->NameAtom())};
return ReportErrorToConsole("InvalidChild", argv);
}
//==========================
nsContainerFrame* NS_NewMathMLmathBlockFrame(PresShell* aPresShell,
ComputedStyle* aStyle) {
auto newFrame = new (aPresShell)
nsMathMLmathBlockFrame(aStyle, aPresShell->GetPresContext());
newFrame->AddStateBits(NS_BLOCK_FORMATTING_CONTEXT_STATE_BITS);
return newFrame;
}
NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmathBlockFrame)
NS_QUERYFRAME_HEAD(nsMathMLmathBlockFrame)
NS_QUERYFRAME_ENTRY(nsMathMLmathBlockFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsBlockFrame)
nsContainerFrame* NS_NewMathMLmathInlineFrame(PresShell* aPresShell,
ComputedStyle* aStyle) {
return new (aPresShell)
nsMathMLmathInlineFrame(aStyle, aPresShell->GetPresContext());
}
NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmathInlineFrame)
NS_QUERYFRAME_HEAD(nsMathMLmathInlineFrame)
NS_QUERYFRAME_ENTRY(nsIMathMLFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsInlineFrame)
