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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 */
#ifndef nsTextFrame_h__
#define nsTextFrame_h__
#include "mozilla/Attributes.h"
#include "mozilla/EventForwards.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/dom/Text.h"
#include "nsIFrame.h"
#include "nsFrameSelection.h"
#include "nsSplittableFrame.h"
#include "nsLineBox.h"
#include "gfxSkipChars.h"
#include "gfxTextRun.h"
#include "nsDisplayList.h"
#include "nsFontMetrics.h"
#include "JustificationUtils.h"
#include "RubyUtils.h"
// Undo the windows.h damage
#if defined(XP_WIN) && defined(DrawText)
# undef DrawText
class nsTextPaintStyle;
struct SelectionDetails;
class nsTextFragment;
namespace mozilla {
class SVGContextPaint;
class SVGTextFrame;
} // namespace mozilla
class nsTextFrame : public nsIFrame {
typedef mozilla::LayoutDeviceRect LayoutDeviceRect;
typedef mozilla::SelectionTypeMask SelectionTypeMask;
typedef mozilla::SelectionType SelectionType;
typedef mozilla::TextRangeStyle TextRangeStyle;
typedef mozilla::gfx::DrawTarget DrawTarget;
typedef mozilla::gfx::Point Point;
typedef mozilla::gfx::Rect Rect;
typedef mozilla::gfx::Size Size;
typedef gfxTextRun::Range Range;
enum TextRunType : uint8_t;
struct TabWidthStore;
* An implementation of gfxTextRun::PropertyProvider that computes spacing and
* hyphenation based on CSS properties for a text frame.
class MOZ_STACK_CLASS PropertyProvider final
: public gfxTextRun::PropertyProvider {
typedef gfxTextRun::Range Range;
typedef gfxTextRun::HyphenType HyphenType;
typedef mozilla::gfx::DrawTarget DrawTarget;
* Use this constructor for reflow, when we don't know what text is
* really mapped by the frame and we have a lot of other data around.
* @param aLength can be INT32_MAX to indicate we cover all the text
* associated with aFrame up to where its flow chain ends in the given
* textrun. If INT32_MAX is passed, justification and hyphen-related methods
* cannot be called, nor can GetOriginalLength().
PropertyProvider(gfxTextRun* aTextRun, const nsStyleText* aTextStyle,
const nsTextFragment* aFrag, nsTextFrame* aFrame,
const gfxSkipCharsIterator& aStart, int32_t aLength,
nsIFrame* aLineContainer,
nscoord aOffsetFromBlockOriginForTabs,
nsTextFrame::TextRunType aWhichTextRun);
* Use this constructor after the frame has been reflowed and we don't
* have other data around. Gets everything from the frame. EnsureTextRun
* *must* be called before this!!!
PropertyProvider(nsTextFrame* aFrame, const gfxSkipCharsIterator& aStart,
nsTextFrame::TextRunType aWhichTextRun,
nsFontMetrics* aFontMetrics);
* As above, but assuming we want the inflated text run and associated
* metrics.
PropertyProvider(nsTextFrame* aFrame, const gfxSkipCharsIterator& aStart)
: PropertyProvider(aFrame, aStart, nsTextFrame::eInflated,
aFrame->InflatedFontMetrics()) {}
// Call this after construction if you're not going to reflow the text
void InitializeForDisplay(bool aTrimAfter);
void InitializeForMeasure();
void GetSpacing(Range aRange, Spacing* aSpacing) const final;
gfxFloat GetHyphenWidth() const final;
void GetHyphenationBreaks(Range aRange,
HyphenType* aBreakBefore) const final;
mozilla::StyleHyphens GetHyphensOption() const final {
return mTextStyle->mHyphens;
already_AddRefed<DrawTarget> GetDrawTarget() const final;
uint32_t GetAppUnitsPerDevUnit() const final {
return mTextRun->GetAppUnitsPerDevUnit();
void GetSpacingInternal(Range aRange, Spacing* aSpacing,
bool aIgnoreTabs) const;
* Compute the justification information in given DOM range, return
* justification info and assignments if requested.
mozilla::JustificationInfo ComputeJustification(
Range aRange,
nsTArray<mozilla::JustificationAssignment>* aAssignments = nullptr);
const nsTextFrame* GetFrame() const { return mFrame; }
// This may not be equal to the frame offset/length in because we may have
// adjusted for whitespace trimming according to the state bits set in the
// frame (for the static provider)
const gfxSkipCharsIterator& GetStart() const { return mStart; }
// May return INT32_MAX if that was given to the constructor
uint32_t GetOriginalLength() const {
NS_ASSERTION(mLength != INT32_MAX, "Length not known");
return mLength;
const nsTextFragment* GetFragment() const { return mFrag; }
gfxFontGroup* GetFontGroup() const {
if (!mFontGroup) {
mFontGroup = GetFontMetrics()->GetThebesFontGroup();
return mFontGroup;
nsFontMetrics* GetFontMetrics() const {
if (!mFontMetrics) {
return mFontMetrics;
void CalcTabWidths(Range aTransformedRange, gfxFloat aTabWidth) const;
gfxFloat MinTabAdvance() const;
const gfxSkipCharsIterator& GetEndHint() const { return mTempIterator; }
void SetupJustificationSpacing(bool aPostReflow);
void InitFontGroupAndFontMetrics() const;
const RefPtr<gfxTextRun> mTextRun;
mutable gfxFontGroup* mFontGroup;
mutable RefPtr<nsFontMetrics> mFontMetrics;
const nsStyleText* mTextStyle;
const nsTextFragment* mFrag;
const nsIFrame* mLineContainer;
nsTextFrame* mFrame;
gfxSkipCharsIterator mStart; // Offset in original and transformed string
const gfxSkipCharsIterator mTempIterator;
// Either null, or pointing to the frame's TabWidthProperty.
mutable nsTextFrame::TabWidthStore* mTabWidths;
// How far we've done tab-width calculation; this is ONLY valid when
// mTabWidths is nullptr (otherwise rely on mTabWidths->mLimit instead).
// It's a DOM offset relative to the current frame's offset.
mutable uint32_t mTabWidthsAnalyzedLimit;
int32_t mLength; // DOM string length, may be INT32_MAX
const gfxFloat mWordSpacing; // space for each whitespace char
const gfxFloat mLetterSpacing; // space for each letter
mutable gfxFloat mMinTabAdvance; // min advance for <tab> char
mutable gfxFloat mHyphenWidth;
mutable gfxFloat mOffsetFromBlockOriginForTabs;
// The values in mJustificationSpacings corresponds to unskipped
// characters start from mJustificationArrayStart.
uint32_t mJustificationArrayStart;
nsTArray<Spacing> mJustificationSpacings;
const bool mReflowing;
const nsTextFrame::TextRunType mWhichTextRun;
explicit nsTextFrame(ComputedStyle* aStyle, nsPresContext* aPresContext,
ClassID aID = kClassID)
: nsIFrame(aStyle, aPresContext, aID),
mAscent(0) {}
friend class nsContinuingTextFrame;
// nsQueryFrame
// nsIFrame
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) final;
void Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
void DestroyFrom(nsIFrame* aDestructRoot,
PostDestroyData& aPostDestroyData) override;
mozilla::Maybe<Cursor> GetCursor(const nsPoint&) final;
nsresult CharacterDataChanged(const CharacterDataChangeInfo&) final;
nsTextFrame* GetPrevContinuation() const override { return nullptr; }
nsTextFrame* GetNextContinuation() const final { return mNextContinuation; }
void SetNextContinuation(nsIFrame* aNextContinuation) final {
NS_ASSERTION(!aNextContinuation || Type() == aNextContinuation->Type(),
"setting a next continuation with incorrect type!");
!nsSplittableFrame::IsInNextContinuationChain(aNextContinuation, this),
"creating a loop in continuation chain!");
mNextContinuation = static_cast<nsTextFrame*>(aNextContinuation);
if (aNextContinuation)
// Setting a non-fluid continuation might affect our flow length (they're
// quite rare so we assume it always does) so we delete our cached value:
if (GetContent()->HasFlag(NS_HAS_FLOWLENGTH_PROPERTY)) {
nsTextFrame* GetNextInFlow() const final {
return mNextContinuation && mNextContinuation->HasAnyStateBits(
? mNextContinuation
: nullptr;
void SetNextInFlow(nsIFrame* aNextInFlow) final {
NS_ASSERTION(!aNextInFlow || Type() == aNextInFlow->Type(),
"setting a next in flow with incorrect type!");
!nsSplittableFrame::IsInNextContinuationChain(aNextInFlow, this),
"creating a loop in continuation chain!");
mNextContinuation = static_cast<nsTextFrame*>(aNextInFlow);
if (mNextContinuation &&
!mNextContinuation->HasAnyStateBits(NS_FRAME_IS_FLUID_CONTINUATION)) {
// Changing from non-fluid to fluid continuation might affect our flow
// length, so we delete our cached value:
if (GetContent()->HasFlag(NS_HAS_FLOWLENGTH_PROPERTY)) {
if (aNextInFlow) {
nsTextFrame* LastInFlow() const final;
nsTextFrame* LastContinuation() const final;
bool IsFrameOfType(uint32_t aFlags) const final {
// Set the frame state bit for text frames to mark them as replaced.
// XXX kipp: temporary
return nsIFrame::IsFrameOfType(
aFlags & ~(nsIFrame::eReplaced | nsIFrame::eLineParticipant));
bool ShouldSuppressLineBreak() const {
// If the parent frame of the text frame is ruby content box, it must
// suppress line break inside. This check is necessary, because when
// a whitespace is only contained by pseudo ruby frames, its style
// context won't have SuppressLineBreak bit set.
if (mozilla::RubyUtils::IsRubyContentBox(GetParent()->Type())) {
return true;
return Style()->ShouldSuppressLineBreak();
void InvalidateFrame(uint32_t aDisplayItemKey = 0,
bool aRebuildDisplayItems = true) final;
void InvalidateFrameWithRect(const nsRect& aRect,
uint32_t aDisplayItemKey = 0,
bool aRebuildDisplayItems = true) final;
void List(FILE* out = stderr, const char* aPrefix = "",
ListFlags aFlags = ListFlags()) const final;
nsresult GetFrameName(nsAString& aResult) const final;
void ToCString(nsCString& aBuf, int32_t* aTotalContentLength) const;
void ListTextRuns(FILE* out,
nsTHashtable<nsVoidPtrHashKey>& aSeen) const final;
// Returns this text frame's content's text fragment.
// Assertions in Init() ensure we only ever get a Text node as content.
const nsTextFragment* TextFragment() const {
return &mContent->AsText()->TextFragment();
ContentOffsets CalcContentOffsetsFromFramePoint(const nsPoint& aPoint) final;
ContentOffsets GetCharacterOffsetAtFramePoint(const nsPoint& aPoint);
* This is called only on the primary text frame. It indicates that
* the selection state of the given character range has changed.
* Frames corresponding to the character range are unconditionally invalidated
* (Selection::Repaint depends on this).
* @param aStart start of character range.
* @param aEnd end (exclusive) of character range.
* @param aSelected true iff the character range is now selected.
* @param aType the type of the changed selection.
void SelectionStateChanged(uint32_t aStart, uint32_t aEnd, bool aSelected,
SelectionType aSelectionType);
FrameSearchResult PeekOffsetNoAmount(bool aForward, int32_t* aOffset) final;
FrameSearchResult PeekOffsetCharacter(
bool aForward, int32_t* aOffset,
PeekOffsetCharacterOptions aOptions = PeekOffsetCharacterOptions()) final;
FrameSearchResult PeekOffsetWord(bool aForward, bool aWordSelectEatSpace,
bool aIsKeyboardSelect, int32_t* aOffset,
PeekWordState* aState,
bool aTrimSpaces) final;
nsresult CheckVisibility(nsPresContext* aContext, int32_t aStartIndex,
int32_t aEndIndex, bool aRecurse, bool* aFinished,
bool* _retval) final;
// Flags for aSetLengthFlags
// Update offsets to account for new length. This may clear mTextRun.
void SetLength(int32_t aLength, nsLineLayout* aLineLayout,
uint32_t aSetLengthFlags = 0);
nsresult GetOffsets(int32_t& start, int32_t& end) const final;
void AdjustOffsetsForBidi(int32_t start, int32_t end) final;
nsresult GetPointFromOffset(int32_t inOffset, nsPoint* outPoint) final;
nsresult GetCharacterRectsInRange(int32_t aInOffset, int32_t aLength,
nsTArray<nsRect>& aRects) final;
nsresult GetChildFrameContainingOffset(int32_t inContentOffset, bool inHint,
int32_t* outFrameContentOffset,
nsIFrame** outChildFrame) final;
bool IsEmpty() final;
bool IsSelfEmpty() final { return IsEmpty(); }
nscoord GetLogicalBaseline(mozilla::WritingMode aWritingMode) const final;
bool HasSignificantTerminalNewline() const final;
* Returns true if this text frame is logically adjacent to the end of the
* line.
bool IsAtEndOfLine() const;
* Call this only after reflow the frame. Returns true if non-collapsed
* characters are present.
bool HasNoncollapsedCharacters() const {
mozilla::a11y::AccType AccessibleType() final;
float GetFontSizeInflation() const;
bool IsCurrentFontInflation(float aInflation) const;
bool HasFontSizeInflation() const {
return HasAnyStateBits(TEXT_HAS_FONT_INFLATION);
void SetFontSizeInflation(float aInflation);
void MarkIntrinsicISizesDirty() final;
nscoord GetMinISize(gfxContext* aRenderingContext) final;
nscoord GetPrefISize(gfxContext* aRenderingContext) final;
void AddInlineMinISize(gfxContext* aRenderingContext,
InlineMinISizeData* aData) override;
void AddInlinePrefISize(gfxContext* aRenderingContext,
InlinePrefISizeData* aData) override;
SizeComputationResult ComputeSize(
gfxContext* aRenderingContext, mozilla::WritingMode aWM,
const mozilla::LogicalSize& aCBSize, nscoord aAvailableISize,
const mozilla::LogicalSize& aMargin,
const mozilla::LogicalSize& aBorderPadding,
const mozilla::StyleSizeOverrides& aSizeOverrides,
mozilla::ComputeSizeFlags aFlags) final;
nsRect ComputeTightBounds(DrawTarget* aDrawTarget) const final;
nsresult GetPrefWidthTightBounds(gfxContext* aContext, nscoord* aX,
nscoord* aXMost) final;
void Reflow(nsPresContext* aPresContext, ReflowOutput& aMetrics,
const ReflowInput& aReflowInput, nsReflowStatus& aStatus) final;
bool CanContinueTextRun() const final;
// Method that is called for a text frame that is logically
// adjacent to the end of the line (i.e. followed only by empty text frames,
// placeholders or inlines containing such).
struct TrimOutput {
// true if we trimmed some space or changed metrics in some other way.
// In this case, we should call RecomputeOverflow on this frame.
bool mChanged;
// an amount to *subtract* from the frame's width (zero if !mChanged)
nscoord mDeltaWidth;
TrimOutput TrimTrailingWhiteSpace(DrawTarget* aDrawTarget);
RenderedText GetRenderedText(
uint32_t aStartOffset = 0, uint32_t aEndOffset = UINT32_MAX,
TextOffsetType aOffsetType = TextOffsetType::OffsetsInContentText,
TrailingWhitespace aTrimTrailingWhitespace =
TrailingWhitespace::Trim) final;
mozilla::OverflowAreas RecomputeOverflow(nsIFrame* aBlockFrame,
bool aIncludeShadows = true);
enum TextRunType : uint8_t {
// Anything in reflow (but not intrinsic width calculation) or
// painting should use the inflated text run (i.e., with font size
// inflation applied).
// Intrinsic width calculation should use the non-inflated text run.
// When there is font size inflation, it will be different.
void AddInlineMinISizeForFlow(gfxContext* aRenderingContext,
nsIFrame::InlineMinISizeData* aData,
TextRunType aTextRunType);
void AddInlinePrefISizeForFlow(gfxContext* aRenderingContext,
InlinePrefISizeData* aData,
TextRunType aTextRunType);
* Calculate the horizontal bounds of the grapheme clusters that fit entirely
* inside the given left[top]/right[bottom] edges (which are positive lengths
* from the respective frame edge). If an input value is zero it is ignored
* and the result for that edge is zero. All out parameter values are
* undefined when the method returns false.
* @return true if at least one whole grapheme cluster fit between the edges
bool MeasureCharClippedText(nscoord aVisIStartEdge, nscoord aVisIEndEdge,
nscoord* aSnappedStartEdge,
nscoord* aSnappedEndEdge);
* Same as above; this method also the returns the corresponding text run
* offset and number of characters that fit. All out parameter values are
* undefined when the method returns false.
* @return true if at least one whole grapheme cluster fit between the edges
bool MeasureCharClippedText(PropertyProvider& aProvider,
nscoord aVisIStartEdge, nscoord aVisIEndEdge,
uint32_t* aStartOffset, uint32_t* aMaxLength,
nscoord* aSnappedStartEdge,
nscoord* aSnappedEndEdge);
* Return true if this box has some text to display.
* It returns false if at least one of these conditions are met:
* a. the frame hasn't been reflowed yet
* b. GetContentLength() == 0
* c. it contains only non-significant white-space
bool HasNonSuppressedText() const;
* Object with various callbacks for PaintText() to invoke for different parts
* of the frame's text rendering, when we're generating paths rather than
* painting.
* Callbacks are invoked in the following order:
* NotifySelectionBackgroundNeedsFill?
* PaintDecorationLine*
* NotifyBeforeText
* NotifyGlyphPathEmitted*
* NotifyAfterText
* PaintDecorationLine*
* PaintSelectionDecorationLine*
* The color of each part of the frame's text rendering is passed as an
* argument to the NotifyBefore* callback for that part. The nscolor can take
* on one of the three selection special colors defined in LookAndFeel.h --
struct DrawPathCallbacks : gfxTextRunDrawCallbacks {
* @param aShouldPaintSVGGlyphs Whether SVG glyphs should be painted.
explicit DrawPathCallbacks(bool aShouldPaintSVGGlyphs = false)
: gfxTextRunDrawCallbacks(aShouldPaintSVGGlyphs) {}
* Called to have the selection highlight drawn before the text is drawn
* over the top.
virtual void NotifySelectionBackgroundNeedsFill(const Rect& aBackgroundRect,
nscolor aColor,
DrawTarget& aDrawTarget) {}
* Called before (for under/over-line) or after (for line-through) the text
* is drawn to have a text decoration line drawn.
virtual void PaintDecorationLine(Rect aPath, nscolor aColor) {}
* Called after selected text is drawn to have a decoration line drawn over
* the text. (All types of text decoration are drawn after the text when
* text is selected.)
virtual void PaintSelectionDecorationLine(Rect aPath, nscolor aColor) {}
* Called just before any paths have been emitted to the gfxContext
* for the glyphs of the frame's text.
virtual void NotifyBeforeText(nscolor aColor) {}
* Called just after all the paths have been emitted to the gfxContext
* for the glyphs of the frame's text.
virtual void NotifyAfterText() {}
* Called just before a path corresponding to a selection decoration line
* has been emitted to the gfxContext.
virtual void NotifyBeforeSelectionDecorationLine(nscolor aColor) {}
* Called just after a path corresponding to a selection decoration line
* has been emitted to the gfxContext.
virtual void NotifySelectionDecorationLinePathEmitted() {}
struct PaintTextParams {
gfxContext* context;
mozilla::gfx::Point framePt;
LayoutDeviceRect dirtyRect;
mozilla::SVGContextPaint* contextPaint = nullptr;
DrawPathCallbacks* callbacks = nullptr;
enum {
PaintText, // Normal text painting.
GenerateTextMask // To generate a mask from a text frame. Should
// only paint text itself with opaque color.
// Text shadow, text selection color and text
// decoration are all discarded in this state.
uint8_t state = PaintText;
explicit PaintTextParams(gfxContext* aContext) : context(aContext) {}
bool IsPaintText() const { return state == PaintText; }
bool IsGenerateTextMask() const { return state == GenerateTextMask; }
struct PaintTextSelectionParams : PaintTextParams {
mozilla::gfx::Point textBaselinePt;
PropertyProvider* provider = nullptr;
Range contentRange;
nsTextPaintStyle* textPaintStyle = nullptr;
Range glyphRange;
explicit PaintTextSelectionParams(const PaintTextParams& aParams)
: PaintTextParams(aParams) {}
struct DrawTextRunParams {
gfxContext* context;
PropertyProvider* provider = nullptr;
gfxFloat* advanceWidth = nullptr;
mozilla::SVGContextPaint* contextPaint = nullptr;
DrawPathCallbacks* callbacks = nullptr;
nscolor textColor = NS_RGBA(0, 0, 0, 0);
nscolor textStrokeColor = NS_RGBA(0, 0, 0, 0);
float textStrokeWidth = 0.0f;
bool drawSoftHyphen = false;
explicit DrawTextRunParams(gfxContext* aContext) : context(aContext) {}
struct DrawTextParams : DrawTextRunParams {
mozilla::gfx::Point framePt;
LayoutDeviceRect dirtyRect;
const nsTextPaintStyle* textStyle = nullptr;
const nsDisplayText::ClipEdges* clipEdges = nullptr;
const nscolor* decorationOverrideColor = nullptr;
Range glyphRange;
explicit DrawTextParams(gfxContext* aContext)
: DrawTextRunParams(aContext) {}
// Primary frame paint method called from nsDisplayText. Can also be used
// to generate paths rather than paint the frame's text by passing a callback
// object. The private DrawText() is what applies the text to a graphics
// context.
void PaintText(const PaintTextParams& aParams, const nscoord aVisIStartEdge,
const nscoord aVisIEndEdge, const nsPoint& aToReferenceFrame,
const bool aIsSelected, float aOpacity = 1.0f);
// helper: paint text frame when we're impacted by at least one selection.
// Return false if the text was not painted and we should continue with
// the fast path.
bool PaintTextWithSelection(const PaintTextSelectionParams& aParams,
const nsDisplayText::ClipEdges& aClipEdges);
// helper: paint text with foreground and background colors determined
// by selection(s). Also computes a mask of all selection types applying to
// our text, returned in aAllSelectionTypeMask.
// Return false if the text was not painted and we should continue with
// the fast path.
bool PaintTextWithSelectionColors(
const PaintTextSelectionParams& aParams,
const mozilla::UniquePtr<SelectionDetails>& aDetails,
SelectionTypeMask* aAllSelectionTypeMask,
const nsDisplayText::ClipEdges& aClipEdges);
// helper: paint text decorations for text selected by aSelectionType
void PaintTextSelectionDecorations(
const PaintTextSelectionParams& aParams,
const mozilla::UniquePtr<SelectionDetails>& aDetails,
SelectionType aSelectionType);
void DrawEmphasisMarks(gfxContext* aContext, mozilla::WritingMode aWM,
const mozilla::gfx::Point& aTextBaselinePt,
const mozilla::gfx::Point& aFramePt, Range aRange,
const nscolor* aDecorationOverrideColor,
PropertyProvider* aProvider);
nscolor GetCaretColorAt(int32_t aOffset) final;
// @param aSelectionFlags may be multiple of nsISelectionDisplay::DISPLAY_*.
// @return nsISelectionController.idl's `getDisplaySelection`.
int16_t GetSelectionStatus(int16_t* aSelectionFlags);
int32_t GetContentOffset() const { return mContentOffset; }
int32_t GetContentLength() const {
NS_ASSERTION(GetContentEnd() - mContentOffset >= 0, "negative length");
return GetContentEnd() - mContentOffset;
int32_t GetContentEnd() const;
// This returns the length the frame thinks it *should* have after it was
// last reflowed (0 if it hasn't been reflowed yet). This should be used only
// when setting up the text offsets for a new continuation frame.
int32_t GetContentLengthHint() const { return mContentLengthHint; }
// Compute the length of the content mapped by this frame
// and all its in-flow siblings. Basically this means starting at
// mContentOffset and going to the end of the text node or the next bidi
// continuation boundary.
int32_t GetInFlowContentLength();
* Acquires the text run for this content, if necessary.
* @param aWhichTextRun indicates whether to get an inflated or non-inflated
* text run
* @param aRefDrawTarget the DrawTarget to use as a reference for creating the
* textrun, if available (if not, we'll create one which will just be slower)
* @param aLineContainer the block ancestor for this frame, or nullptr if
* unknown
* @param aFlowEndInTextRun if non-null, this returns the textrun offset of
* end of the text associated with this frame and its in-flow siblings
* @return a gfxSkipCharsIterator set up to map DOM offsets for this frame
* to offsets into the textrun; its initial offset is set to this frame's
* content offset
gfxSkipCharsIterator EnsureTextRun(
TextRunType aWhichTextRun, DrawTarget* aRefDrawTarget = nullptr,
nsIFrame* aLineContainer = nullptr,
const nsLineList::iterator* aLine = nullptr,
uint32_t* aFlowEndInTextRun = nullptr);
gfxTextRun* GetTextRun(TextRunType aWhichTextRun) const {
if (aWhichTextRun == eInflated || !HasFontSizeInflation()) return mTextRun;
return GetUninflatedTextRun();
gfxTextRun* GetUninflatedTextRun() const;
void SetTextRun(gfxTextRun* aTextRun, TextRunType aWhichTextRun,
float aInflation);
bool IsInTextRunUserData() const {
return HasAnyStateBits(TEXT_IN_TEXTRUN_USER_DATA |
* Notify the frame that it should drop its pointer to a text run.
* Returns whether the text run was removed (i.e., whether it was
* associated with this frame, either as its inflated or non-inflated
* text run.
bool RemoveTextRun(gfxTextRun* aTextRun);
* Clears out |mTextRun| (or the uninflated text run, when aInflated
* is nsTextFrame::eNotInflated and there is inflation) from all frames that
* hold a reference to it, starting at |aStartContinuation|, or if it's
* nullptr, starting at |this|. Deletes the text run if all references
* were cleared and it's not cached.
void ClearTextRun(nsTextFrame* aStartContinuation, TextRunType aWhichTextRun);
void ClearTextRuns() {
ClearTextRun(nullptr, nsTextFrame::eInflated);
if (HasFontSizeInflation()) {
ClearTextRun(nullptr, nsTextFrame::eNotInflated);
* Wipe out references to textrun(s) without deleting the textruns.
void DisconnectTextRuns();
// Get the DOM content range mapped by this frame after excluding
// whitespace subject to start-of-line and end-of-line trimming.
// The textrun must have been created before calling this.
struct TrimmedOffsets {
int32_t mStart;
int32_t mLength;
int32_t GetEnd() const { return mStart + mLength; }
enum class TrimmedOffsetFlags : uint8_t {
Default = 0,
NotPostReflow = 1 << 0,
NoTrimAfter = 1 << 1,
NoTrimBefore = 1 << 2
TrimmedOffsets GetTrimmedOffsets(
const nsTextFragment* aFrag,
TrimmedOffsetFlags aFlags = TrimmedOffsetFlags::Default) const;
// Similar to Reflow(), but for use from nsLineLayout
void ReflowText(nsLineLayout& aLineLayout, nscoord aAvailableWidth,
DrawTarget* aDrawTarget, ReflowOutput& aMetrics,
nsReflowStatus& aStatus);
bool IsFloatingFirstLetterChild() const;
bool IsInitialLetterChild() const;
bool ComputeCustomOverflow(mozilla::OverflowAreas& aOverflowAreas) final;
bool ComputeCustomOverflowInternal(mozilla::OverflowAreas& aOverflowAreas,
bool aIncludeShadows);
void AssignJustificationGaps(const mozilla::JustificationAssignment& aAssign);
mozilla::JustificationAssignment GetJustificationAssignment() const;
uint32_t CountGraphemeClusters() const;
bool HasAnyNoncollapsedCharacters() final;
* Call this after you have manually changed the text node contents without
* notifying that change. This behaves as if all the text contents changed.
* (You should only use this for native anonymous content.)
void NotifyNativeAnonymousTextnodeChange(uint32_t aOldLength);
void SetInflatedFontMetrics(nsFontMetrics* aMetrics) {
mFontMetrics = aMetrics;
nsFontMetrics* InflatedFontMetrics() const { return mFontMetrics; }
nsRect WebRenderBounds();
virtual ~nsTextFrame();
friend class nsDisplayTextGeometry;
friend class nsDisplayText;
RefPtr<nsFontMetrics> mFontMetrics;
RefPtr<gfxTextRun> mTextRun;
nsTextFrame* mNextContinuation;
// The key invariant here is that mContentOffset never decreases along
// a next-continuation chain. And of course mContentOffset is always <= the
// the text node's content length, and the mContentOffset for the first frame
// is always 0. Furthermore the text mapped by a frame is determined by
// GetContentOffset() and GetContentLength()/GetContentEnd(), which get
// the length from the difference between this frame's offset and the next
// frame's offset, or the text length if there is no next frame. This means
// the frames always map the text node without overlapping or leaving any
// gaps.
int32_t mContentOffset;
// This does *not* indicate the length of text currently mapped by the frame;
// instead it's a hint saying that this frame *wants* to map this much text
// so if we create a new continuation, this is where that continuation should
// start.
int32_t mContentLengthHint;
nscoord mAscent;
* Return true if the frame is part of a Selection.
* Helper method to implement the public IsSelected() API.
bool IsFrameSelected() const final;
mozilla::UniquePtr<SelectionDetails> GetSelectionDetails();
void UnionAdditionalOverflow(nsPresContext* aPresContext, nsIFrame* aBlock,
PropertyProvider& aProvider,
nsRect* aInkOverflowRect,
bool aIncludeTextDecorations,
bool aIncludeShadows);
// Update information of emphasis marks, and return the visial
// overflow rect of the emphasis marks.
nsRect UpdateTextEmphasis(mozilla::WritingMode aWM,
PropertyProvider& aProvider);
struct PaintShadowParams {
gfxTextRun::Range range;
LayoutDeviceRect dirtyRect;
mozilla::gfx::Point framePt;
mozilla::gfx::Point textBaselinePt;
gfxContext* context;
nscolor foregroundColor = NS_RGBA(0, 0, 0, 0);
const nsDisplayText::ClipEdges* clipEdges = nullptr;
PropertyProvider* provider = nullptr;
nscoord leftSideOffset = 0;
explicit PaintShadowParams(const PaintTextParams& aParams)
: dirtyRect(aParams.dirtyRect),
context(aParams.context) {}
void PaintOneShadow(const PaintShadowParams& aParams,
const mozilla::StyleSimpleShadow& aShadowDetails,
gfxRect& aBoundingBox, uint32_t aBlurFlags);
void PaintShadows(mozilla::Span<const mozilla::StyleSimpleShadow>,
const PaintShadowParams& aParams);
struct LineDecoration {
nsIFrame* mFrame;
// This is represents the offset from our baseline to mFrame's baseline;
// positive offsets are *above* the baseline and negative offsets below
nscoord mBaselineOffset;
// This represents the offset from the initial position of the underline
const mozilla::LengthPercentageOrAuto mTextUnderlineOffset;
// for CSS property text-decoration-thickness, the width refers to the
// thickness of the decoration line
const mozilla::StyleTextDecorationLength mTextDecorationThickness;
nscolor mColor;
uint8_t mStyle;
// The text-underline-position property; affects the underline offset only
// if mTextUnderlineOffset is auto.
const mozilla::StyleTextUnderlinePosition mTextUnderlinePosition;
LineDecoration(nsIFrame* const aFrame, const nscoord aOff,
mozilla::StyleTextUnderlinePosition aUnderlinePosition,
const mozilla::LengthPercentageOrAuto& aUnderlineOffset,
const mozilla::StyleTextDecorationLength& aDecThickness,
const nscolor aColor, const uint8_t aStyle)
: mFrame(aFrame),
mTextUnderlinePosition(aUnderlinePosition) {}
LineDecoration(const LineDecoration& aOther) = default;
bool operator==(const LineDecoration& aOther) const {
return mFrame == aOther.mFrame && mStyle == aOther.mStyle &&
mColor == aOther.mColor &&
mBaselineOffset == aOther.mBaselineOffset &&
mTextUnderlinePosition == aOther.mTextUnderlinePosition &&
mTextUnderlineOffset == aOther.mTextUnderlineOffset &&
mTextDecorationThickness == aOther.mTextDecorationThickness;
bool operator!=(const LineDecoration& aOther) const {
return !(*this == aOther);
struct TextDecorations {
AutoTArray<LineDecoration, 1> mOverlines, mUnderlines, mStrikes;
TextDecorations() = default;
bool HasDecorationLines() const {
return HasUnderline() || HasOverline() || HasStrikeout();
bool HasUnderline() const { return !mUnderlines.IsEmpty(); }
bool HasOverline() const { return !mOverlines.IsEmpty(); }
bool HasStrikeout() const { return !mStrikes.IsEmpty(); }
bool operator==(const TextDecorations& aOther) const {
return mOverlines == aOther.mOverlines &&
mUnderlines == aOther.mUnderlines && mStrikes == aOther.mStrikes;
bool operator!=(const TextDecorations& aOther) const {
return !(*this == aOther);
enum TextDecorationColorResolution { eResolvedColors, eUnresolvedColors };
void GetTextDecorations(nsPresContext* aPresContext,
TextDecorationColorResolution aColorResolution,
TextDecorations& aDecorations);
void DrawTextRun(Range aRange, const mozilla::gfx::Point& aTextBaselinePt,
const DrawTextRunParams& aParams);
void DrawTextRunAndDecorations(Range aRange,
const mozilla::gfx::Point& aTextBaselinePt,
const DrawTextParams& aParams,
const TextDecorations& aDecorations);
void DrawText(Range aRange, const mozilla::gfx::Point& aTextBaselinePt,
const DrawTextParams& aParams);
// Set non empty rect to aRect, it should be overflow rect or frame rect.
// If the result rect is larger than the given rect, this returns true.
bool CombineSelectionUnderlineRect(nsPresContext* aPresContext,
nsRect& aRect);
* Utility methods to paint selection.
void DrawSelectionDecorations(
gfxContext* aContext, const LayoutDeviceRect& aDirtyRect,
mozilla::SelectionType aSelectionType, nsTextPaintStyle& aTextPaintStyle,
const TextRangeStyle& aRangeStyle, const Point& aPt,
gfxFloat aICoordInFrame, gfxFloat aWidth, gfxFloat aAscent,
const gfxFont::Metrics& aFontMetrics, DrawPathCallbacks* aCallbacks,
bool aVertical, mozilla::StyleTextDecorationLine aDecoration);
struct PaintDecorationLineParams;
void PaintDecorationLine(const PaintDecorationLineParams& aParams);
* ComputeDescentLimitForSelectionUnderline() computes the most far position
* where we can put selection underline.
* @return The maximum underline offset from the baseline (positive value
* means that the underline can put below the baseline).
gfxFloat ComputeDescentLimitForSelectionUnderline(
nsPresContext* aPresContext, const gfxFont::Metrics& aFontMetrics);
* This function encapsulates all knowledge of how selections affect
* foreground and background colors.
* @param aForeground the foreground color to use
* @param aBackground the background color to use, or RGBA(0,0,0,0) if no
* background should be painted
* @return true if the selection affects colors, false otherwise
static bool GetSelectionTextColors(SelectionType aSelectionType,
nsTextPaintStyle& aTextPaintStyle,
const TextRangeStyle& aRangeStyle,
nscolor* aForeground,
nscolor* aBackground);
* ComputeSelectionUnderlineHeight() computes selection underline height of
* the specified selection type from the font metrics.
static gfxFloat ComputeSelectionUnderlineHeight(
nsPresContext* aPresContext, const gfxFont::Metrics& aFontMetrics,
SelectionType aSelectionType);
ContentOffsets GetCharacterOffsetAtFramePointInternal(
const nsPoint& aPoint, bool aForInsertionPoint);
static float GetTextCombineScaleFactor(nsTextFrame* aFrame);
void ClearFrameOffsetCache();
void ClearMetrics(ReflowOutput& aMetrics);
* UpdateIteratorFromOffset() updates the iterator from a given offset.
* Also, aInOffset may be updated to cluster start if aInOffset isn't
* the offset of cluster start.
void UpdateIteratorFromOffset(const PropertyProvider& aProperties,
int32_t& aInOffset,
gfxSkipCharsIterator& aIter);
nsPoint GetPointFromIterator(const gfxSkipCharsIterator& aIter,
PropertyProvider& aProperties);