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Diffstat (limited to '')
| -rw-r--r-- | layout/svg/SVGTextFrame.cpp | 5334 |
1 files changed, 5334 insertions, 0 deletions
diff --git a/layout/svg/SVGTextFrame.cpp b/layout/svg/SVGTextFrame.cpp new file mode 100644 index 0000000000..76bff6a1e3 --- /dev/null +++ b/layout/svg/SVGTextFrame.cpp @@ -0,0 +1,5334 @@ +/* -*- 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/. */ + +// Main header first: +#include "SVGTextFrame.h" + +// Keep others in (case-insensitive) order: +#include "DOMSVGPoint.h" +#include "gfx2DGlue.h" +#include "gfxContext.h" +#include "gfxFont.h" +#include "gfxSkipChars.h" +#include "gfxTypes.h" +#include "gfxUtils.h" +#include "LookAndFeel.h" +#include "nsAlgorithm.h" +#include "nsBidiPresUtils.h" +#include "nsBlockFrame.h" +#include "nsCaret.h" +#include "nsContentUtils.h" +#include "nsGkAtoms.h" +#include "nsQuickSort.h" +#include "SVGPaintServerFrame.h" +#include "nsTArray.h" +#include "nsTextFrame.h" +#include "SVGAnimatedNumberList.h" +#include "SVGContentUtils.h" +#include "SVGContextPaint.h" +#include "SVGLengthList.h" +#include "SVGNumberList.h" +#include "nsLayoutUtils.h" +#include "nsFrameSelection.h" +#include "nsStyleStructInlines.h" +#include "mozilla/DisplaySVGItem.h" +#include "mozilla/Likely.h" +#include "mozilla/PresShell.h" +#include "mozilla/SVGObserverUtils.h" +#include "mozilla/SVGOuterSVGFrame.h" +#include "mozilla/SVGUtils.h" +#include "mozilla/dom/DOMPointBinding.h" +#include "mozilla/dom/Selection.h" +#include "mozilla/dom/SVGGeometryElement.h" +#include "mozilla/dom/SVGRect.h" +#include "mozilla/dom/SVGTextContentElementBinding.h" +#include "mozilla/dom/SVGTextPathElement.h" +#include "mozilla/dom/Text.h" +#include "mozilla/gfx/2D.h" +#include "mozilla/gfx/PatternHelpers.h" +#include <algorithm> +#include <cmath> +#include <limits> + +using namespace mozilla::dom; +using namespace mozilla::dom::SVGTextContentElement_Binding; +using namespace mozilla::gfx; +using namespace mozilla::image; + +namespace mozilla { + +// ============================================================================ +// Utility functions + +/** + * Using the specified gfxSkipCharsIterator, converts an offset and length + * in original char indexes to skipped char indexes. + * + * @param aIterator The gfxSkipCharsIterator to use for the conversion. + * @param aOriginalOffset The original offset. + * @param aOriginalLength The original length. + */ +static gfxTextRun::Range ConvertOriginalToSkipped( + gfxSkipCharsIterator& aIterator, uint32_t aOriginalOffset, + uint32_t aOriginalLength) { + uint32_t start = aIterator.ConvertOriginalToSkipped(aOriginalOffset); + aIterator.AdvanceOriginal(aOriginalLength); + return gfxTextRun::Range(start, aIterator.GetSkippedOffset()); +} + +/** + * Converts an nsPoint from app units to user space units using the specified + * nsPresContext and returns it as a gfxPoint. + */ +static gfxPoint AppUnitsToGfxUnits(const nsPoint& aPoint, + const nsPresContext* aContext) { + return gfxPoint(aContext->AppUnitsToGfxUnits(aPoint.x), + aContext->AppUnitsToGfxUnits(aPoint.y)); +} + +/** + * Converts a gfxRect that is in app units to CSS pixels using the specified + * nsPresContext and returns it as a gfxRect. + */ +static gfxRect AppUnitsToFloatCSSPixels(const gfxRect& aRect, + const nsPresContext* aContext) { + return gfxRect(nsPresContext::AppUnitsToFloatCSSPixels(aRect.x), + nsPresContext::AppUnitsToFloatCSSPixels(aRect.y), + nsPresContext::AppUnitsToFloatCSSPixels(aRect.width), + nsPresContext::AppUnitsToFloatCSSPixels(aRect.height)); +} + +/** + * Returns whether a gfxPoint lies within a gfxRect. + */ +static bool Inside(const gfxRect& aRect, const gfxPoint& aPoint) { + return aPoint.x >= aRect.x && aPoint.x < aRect.XMost() && + aPoint.y >= aRect.y && aPoint.y < aRect.YMost(); +} + +/** + * Gets the measured ascent and descent of the text in the given nsTextFrame + * in app units. + * + * @param aFrame The text frame. + * @param aAscent The ascent in app units (output). + * @param aDescent The descent in app units (output). + */ +static void GetAscentAndDescentInAppUnits(nsTextFrame* aFrame, + gfxFloat& aAscent, + gfxFloat& aDescent) { + gfxSkipCharsIterator it = aFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = aFrame->GetTextRun(nsTextFrame::eInflated); + + gfxTextRun::Range range = ConvertOriginalToSkipped( + it, aFrame->GetContentOffset(), aFrame->GetContentLength()); + + textRun->GetLineHeightMetrics(range, aAscent, aDescent); +} + +/** + * Updates an interval by intersecting it with another interval. + * The intervals are specified using a start index and a length. + */ +static void IntersectInterval(uint32_t& aStart, uint32_t& aLength, + uint32_t aStartOther, uint32_t aLengthOther) { + uint32_t aEnd = aStart + aLength; + uint32_t aEndOther = aStartOther + aLengthOther; + + if (aStartOther >= aEnd || aStart >= aEndOther) { + aLength = 0; + } else { + if (aStartOther >= aStart) aStart = aStartOther; + aLength = std::min(aEnd, aEndOther) - aStart; + } +} + +/** + * Intersects an interval as IntersectInterval does but by taking + * the offset and length of the other interval from a + * nsTextFrame::TrimmedOffsets object. + */ +static void TrimOffsets(uint32_t& aStart, uint32_t& aLength, + const nsTextFrame::TrimmedOffsets& aTrimmedOffsets) { + IntersectInterval(aStart, aLength, aTrimmedOffsets.mStart, + aTrimmedOffsets.mLength); +} + +/** + * Returns the closest ancestor-or-self node that is not an SVG <a> + * element. + */ +static nsIContent* GetFirstNonAAncestor(nsIContent* aContent) { + while (aContent && aContent->IsSVGElement(nsGkAtoms::a)) { + aContent = aContent->GetParent(); + } + return aContent; +} + +/** + * Returns whether the given node is a text content element[1], taking into + * account whether it has a valid parent. + * + * For example, in: + * + * <svg xmlns="http://www.w3.org/2000/svg"> + * <text><a/><text/></text> + * <tspan/> + * </svg> + * + * true would be returned for the outer <text> element and the <a> element, + * and false for the inner <text> element (since a <text> is not allowed + * to be a child of another <text>) and the <tspan> element (because it + * must be inside a <text> subtree). + * + * Note that we don't support the <tref> element yet and this function + * returns false for it. + * + * [1] https://svgwg.org/svg2-draft/intro.html#TermTextContentElement + */ +static bool IsTextContentElement(nsIContent* aContent) { + if (aContent->IsSVGElement(nsGkAtoms::text)) { + nsIContent* parent = GetFirstNonAAncestor(aContent->GetParent()); + return !parent || !IsTextContentElement(parent); + } + + if (aContent->IsSVGElement(nsGkAtoms::textPath)) { + nsIContent* parent = GetFirstNonAAncestor(aContent->GetParent()); + return parent && parent->IsSVGElement(nsGkAtoms::text); + } + + return aContent->IsAnyOfSVGElements(nsGkAtoms::a, nsGkAtoms::tspan); +} + +/** + * Returns whether the specified frame is an nsTextFrame that has some text + * content. + */ +static bool IsNonEmptyTextFrame(nsIFrame* aFrame) { + nsTextFrame* textFrame = do_QueryFrame(aFrame); + if (!textFrame) { + return false; + } + + return textFrame->GetContentLength() != 0; +} + +/** + * Takes an nsIFrame and if it is a text frame that has some text content, + * returns it as an nsTextFrame and its corresponding Text. + * + * @param aFrame The frame to look at. + * @param aTextFrame aFrame as an nsTextFrame (output). + * @param aTextNode The Text content of aFrame (output). + * @return true if aFrame is a non-empty text frame, false otherwise. + */ +static bool GetNonEmptyTextFrameAndNode(nsIFrame* aFrame, + nsTextFrame*& aTextFrame, + Text*& aTextNode) { + nsTextFrame* text = do_QueryFrame(aFrame); + bool isNonEmptyTextFrame = text && text->GetContentLength() != 0; + + if (isNonEmptyTextFrame) { + nsIContent* content = text->GetContent(); + NS_ASSERTION(content && content->IsText(), + "unexpected content type for nsTextFrame"); + + Text* node = content->AsText(); + MOZ_ASSERT(node->TextLength() != 0, + "frame's GetContentLength() should be 0 if the text node " + "has no content"); + + aTextFrame = text; + aTextNode = node; + } + + MOZ_ASSERT(IsNonEmptyTextFrame(aFrame) == isNonEmptyTextFrame, + "our logic should agree with IsNonEmptyTextFrame"); + return isNonEmptyTextFrame; +} + +/** + * Returns whether the specified atom is for one of the five + * glyph positioning attributes that can appear on SVG text + * elements -- x, y, dx, dy or rotate. + */ +static bool IsGlyphPositioningAttribute(nsAtom* aAttribute) { + return aAttribute == nsGkAtoms::x || aAttribute == nsGkAtoms::y || + aAttribute == nsGkAtoms::dx || aAttribute == nsGkAtoms::dy || + aAttribute == nsGkAtoms::rotate; +} + +/** + * Returns the position in app units of a given baseline (using an + * SVG dominant-baseline property value) for a given nsTextFrame. + * + * @param aFrame The text frame to inspect. + * @param aTextRun The text run of aFrame. + * @param aDominantBaseline The dominant-baseline value to use. + */ +static nscoord GetBaselinePosition(nsTextFrame* aFrame, gfxTextRun* aTextRun, + StyleDominantBaseline aDominantBaseline, + float aFontSizeScaleFactor) { + WritingMode writingMode = aFrame->GetWritingMode(); + gfxFloat ascent, descent; + aTextRun->GetLineHeightMetrics(ascent, descent); + + auto convertIfVerticalRL = [&](gfxFloat dominantBaseline) { + return writingMode.IsVerticalRL() ? ascent + descent - dominantBaseline + : dominantBaseline; + }; + + switch (aDominantBaseline) { + case StyleDominantBaseline::Hanging: + return convertIfVerticalRL(ascent * 0.2); + case StyleDominantBaseline::TextBeforeEdge: + return convertIfVerticalRL(0); + + case StyleDominantBaseline::Alphabetic: + return writingMode.IsVerticalRL() + ? ascent * 0.5 + : aFrame->GetLogicalBaseline(writingMode); + + case StyleDominantBaseline::Auto: + return convertIfVerticalRL(aFrame->GetLogicalBaseline(writingMode)); + + case StyleDominantBaseline::Middle: + return convertIfVerticalRL(aFrame->GetLogicalBaseline(writingMode) - + SVGContentUtils::GetFontXHeight(aFrame) / 2.0 * + AppUnitsPerCSSPixel() * + aFontSizeScaleFactor); + + case StyleDominantBaseline::TextAfterEdge: + case StyleDominantBaseline::Ideographic: + return writingMode.IsVerticalLR() ? 0 : ascent + descent; + + case StyleDominantBaseline::Central: + return (ascent + descent) / 2.0; + case StyleDominantBaseline::Mathematical: + return convertIfVerticalRL(ascent / 2.0); + } + + MOZ_ASSERT_UNREACHABLE("unexpected dominant-baseline value"); + return convertIfVerticalRL(aFrame->GetLogicalBaseline(writingMode)); +} + +/** + * Truncates an array to be at most the length of another array. + * + * @param aArrayToTruncate The array to truncate. + * @param aReferenceArray The array whose length will be used to truncate + * aArrayToTruncate to. + */ +template <typename T, typename U> +static void TruncateTo(nsTArray<T>& aArrayToTruncate, + const nsTArray<U>& aReferenceArray) { + uint32_t length = aReferenceArray.Length(); + if (aArrayToTruncate.Length() > length) { + aArrayToTruncate.TruncateLength(length); + } +} + +/** + * Asserts that the anonymous block child of the SVGTextFrame has been + * reflowed (or does not exist). Returns null if the child has not been + * reflowed, and the frame otherwise. + * + * We check whether the kid has been reflowed and not the frame itself + * since we sometimes need to call this function during reflow, after the + * kid has been reflowed but before we have cleared the dirty bits on the + * frame itself. + */ +static SVGTextFrame* FrameIfAnonymousChildReflowed(SVGTextFrame* aFrame) { + MOZ_ASSERT(aFrame, "aFrame must not be null"); + nsIFrame* kid = aFrame->PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + MOZ_ASSERT(false, "should have already reflowed the anonymous block child"); + return nullptr; + } + return aFrame; +} + +static double GetContextScale(const gfxMatrix& aMatrix) { + // The context scale is the ratio of the length of the transformed + // diagonal vector (1,1) to the length of the untransformed diagonal + // (which is sqrt(2)). + gfxPoint p = aMatrix.TransformPoint(gfxPoint(1, 1)) - + aMatrix.TransformPoint(gfxPoint(0, 0)); + return SVGContentUtils::ComputeNormalizedHypotenuse(p.x, p.y); +} + +// ============================================================================ +// Utility classes + +// ---------------------------------------------------------------------------- +// TextRenderedRun + +/** + * A run of text within a single nsTextFrame whose glyphs can all be painted + * with a single call to nsTextFrame::PaintText. A text rendered run can + * be created for a sequence of two or more consecutive glyphs as long as: + * + * - Only the first glyph has (or none of the glyphs have) been positioned + * with SVG text positioning attributes + * - All of the glyphs have zero rotation + * - The glyphs are not on a text path + * - The glyphs correspond to content within the one nsTextFrame + * + * A TextRenderedRunIterator produces TextRenderedRuns required for painting a + * whole SVGTextFrame. + */ +struct TextRenderedRun { + using Range = gfxTextRun::Range; + + /** + * Constructs a TextRenderedRun that is uninitialized except for mFrame + * being null. + */ + TextRenderedRun() : mFrame(nullptr) {} + + /** + * Constructs a TextRenderedRun with all of the information required to + * paint it. See the comments documenting the member variables below + * for descriptions of the arguments. + */ + TextRenderedRun(nsTextFrame* aFrame, const gfxPoint& aPosition, + float aLengthAdjustScaleFactor, double aRotate, + float aFontSizeScaleFactor, nscoord aBaseline, + uint32_t aTextFrameContentOffset, + uint32_t aTextFrameContentLength, + uint32_t aTextElementCharIndex) + : mFrame(aFrame), + mPosition(aPosition), + mLengthAdjustScaleFactor(aLengthAdjustScaleFactor), + mRotate(static_cast<float>(aRotate)), + mFontSizeScaleFactor(aFontSizeScaleFactor), + mBaseline(aBaseline), + mTextFrameContentOffset(aTextFrameContentOffset), + mTextFrameContentLength(aTextFrameContentLength), + mTextElementCharIndex(aTextElementCharIndex) {} + + /** + * Returns the text run for the text frame that this rendered run is part of. + */ + gfxTextRun* GetTextRun() const { + mFrame->EnsureTextRun(nsTextFrame::eInflated); + return mFrame->GetTextRun(nsTextFrame::eInflated); + } + + /** + * Returns whether this rendered run is RTL. + */ + bool IsRightToLeft() const { return GetTextRun()->IsRightToLeft(); } + + /** + * Returns whether this rendered run is vertical. + */ + bool IsVertical() const { return GetTextRun()->IsVertical(); } + + /** + * Returns the transform that converts from a <text> element's user space into + * the coordinate space that rendered runs can be painted directly in. + * + * The difference between this method and + * GetTransformFromRunUserSpaceToUserSpace is that when calling in to + * nsTextFrame::PaintText, it will already take into account any left clip + * edge (that is, it doesn't just apply a visual clip to the rendered text, it + * shifts the glyphs over so that they are painted with their left edge at the + * x coordinate passed in to it). Thus we need to account for this in our + * transform. + * + * + * Assume that we have: + * + * <text x="100" y="100" rotate="0 0 1 0 0 * 1">abcdef</text>. + * + * This would result in four text rendered runs: + * + * - one for "ab" + * - one for "c" + * - one for "de" + * - one for "f" + * + * Assume now that we are painting the third TextRenderedRun. It will have + * a left clip edge that is the sum of the advances of "abc", and it will + * have a right clip edge that is the advance of "f". In + * SVGTextFrame::PaintSVG(), we pass in nsPoint() (i.e., the origin) + * as the point at which to paint the text frame, and we pass in the + * clip edge values. The nsTextFrame will paint the substring of its + * text such that the top-left corner of the "d"'s glyph cell will be at + * (0, 0) in the current coordinate system. + * + * Thus, GetTransformFromUserSpaceForPainting must return a transform from + * whatever user space the <text> element is in to a coordinate space in + * device pixels (as that's what nsTextFrame works in) where the origin is at + * the same position as our user space mPositions[i].mPosition value for + * the "d" glyph, which will be (100 + userSpaceAdvance("abc"), 100). + * The translation required to do this (ignoring the scale to get from + * user space to device pixels, and ignoring the + * (100 + userSpaceAdvance("abc"), 100) translation) is: + * + * (-leftEdge, -baseline) + * + * where baseline is the distance between the baseline of the text and the top + * edge of the nsTextFrame. We translate by -leftEdge horizontally because + * the nsTextFrame will already shift the glyphs over by that amount and start + * painting glyphs at x = 0. We translate by -baseline vertically so that + * painting the top edges of the glyphs at y = 0 will result in their + * baselines being at our desired y position. + * + * + * Now for an example with RTL text. Assume our content is now + * <text x="100" y="100" rotate="0 0 1 0 0 1">WERBEH</text>. We'd have + * the following text rendered runs: + * + * - one for "EH" + * - one for "B" + * - one for "ER" + * - one for "W" + * + * Again, we are painting the third TextRenderedRun. The left clip edge + * is the advance of the "W" and the right clip edge is the sum of the + * advances of "BEH". Our translation to get the rendered "ER" glyphs + * in the right place this time is: + * + * (-frameWidth + rightEdge, -baseline) + * + * which is equivalent to: + * + * (-(leftEdge + advance("ER")), -baseline) + * + * The reason we have to shift left additionally by the width of the run + * of glyphs we are painting is that although the nsTextFrame is RTL, + * we still supply the top-left corner to paint the frame at when calling + * nsTextFrame::PaintText, even though our user space positions for each + * glyph in mPositions specifies the origin of each glyph, which for RTL + * glyphs is at the right edge of the glyph cell. + * + * + * For any other use of an nsTextFrame in the context of a particular run + * (such as hit testing, or getting its rectangle), + * GetTransformFromRunUserSpaceToUserSpace should be used. + * + * @param aContext The context to use for unit conversions. + */ + gfxMatrix GetTransformFromUserSpaceForPainting( + nsPresContext* aContext, const nscoord aVisIStartEdge, + const nscoord aVisIEndEdge) const; + + /** + * Returns the transform that converts from "run user space" to a <text> + * element's user space. Run user space is a coordinate system that has the + * same size as the <text>'s user space but rotated and translated such that + * (0,0) is the top-left of the rectangle that bounds the text. + * + * @param aContext The context to use for unit conversions. + */ + gfxMatrix GetTransformFromRunUserSpaceToUserSpace( + nsPresContext* aContext) const; + + /** + * Returns the transform that converts from "run user space" to float pixels + * relative to the nsTextFrame that this rendered run is a part of. + * + * @param aContext The context to use for unit conversions. + */ + gfxMatrix GetTransformFromRunUserSpaceToFrameUserSpace( + nsPresContext* aContext) const; + + /** + * Flag values used for the aFlags arguments of GetRunUserSpaceRect, + * GetFrameUserSpaceRect and GetUserSpaceRect. + */ + enum { + // Includes the fill geometry of the text in the returned rectangle. + eIncludeFill = 1, + // Includes the stroke geometry of the text in the returned rectangle. + eIncludeStroke = 2, + // Don't include any horizontal glyph overflow in the returned rectangle. + eNoHorizontalOverflow = 4 + }; + + /** + * Returns a rectangle that bounds the fill and/or stroke of the rendered run + * in run user space. + * + * @param aContext The context to use for unit conversions. + * @param aFlags A combination of the flags above (eIncludeFill and + * eIncludeStroke) indicating what parts of the text to include in + * the rectangle. + */ + SVGBBox GetRunUserSpaceRect(nsPresContext* aContext, uint32_t aFlags) const; + + /** + * Returns a rectangle that covers the fill and/or stroke of the rendered run + * in "frame user space". + * + * Frame user space is a coordinate space of the same scale as the <text> + * element's user space, but with its rotation set to the rotation of + * the glyphs within this rendered run and its origin set to the position + * such that placing the nsTextFrame there would result in the glyphs in + * this rendered run being at their correct positions. + * + * For example, say we have <text x="100 150" y="100">ab</text>. Assume + * the advance of both the "a" and the "b" is 12 user units, and the + * ascent of the text is 8 user units and its descent is 6 user units, + * and that we are not measuing the stroke of the text, so that we stay + * entirely within the glyph cells. + * + * There will be two text rendered runs, one for "a" and one for "b". + * + * The frame user space for the "a" run will have its origin at + * (100, 100 - 8) in the <text> element's user space and will have its + * axes aligned with the user space (since there is no rotate="" or + * text path involve) and with its scale the same as the user space. + * The rect returned by this method will be (0, 0, 12, 14), since the "a" + * glyph is right at the left of the nsTextFrame. + * + * The frame user space for the "b" run will have its origin at + * (150 - 12, 100 - 8), and scale/rotation the same as above. The rect + * returned by this method will be (12, 0, 12, 14), since we are + * advance("a") horizontally in to the text frame. + * + * @param aContext The context to use for unit conversions. + * @param aFlags A combination of the flags above (eIncludeFill and + * eIncludeStroke) indicating what parts of the text to include in + * the rectangle. + */ + SVGBBox GetFrameUserSpaceRect(nsPresContext* aContext, uint32_t aFlags) const; + + /** + * Returns a rectangle that covers the fill and/or stroke of the rendered run + * in the <text> element's user space. + * + * @param aContext The context to use for unit conversions. + * @param aFlags A combination of the flags above indicating what parts of + * the text to include in the rectangle. + * @param aAdditionalTransform An additional transform to apply to the + * frame user space rectangle before its bounds are transformed into + * user space. + */ + SVGBBox GetUserSpaceRect( + nsPresContext* aContext, uint32_t aFlags, + const gfxMatrix* aAdditionalTransform = nullptr) const; + + /** + * Gets the app unit amounts to clip from the left and right edges of + * the nsTextFrame in order to paint just this rendered run. + * + * Note that if clip edge amounts land in the middle of a glyph, the + * glyph won't be painted at all. The clip edges are thus more of + * a selection mechanism for which glyphs will be painted, rather + * than a geometric clip. + */ + void GetClipEdges(nscoord& aVisIStartEdge, nscoord& aVisIEndEdge) const; + + /** + * Returns the advance width of the whole rendered run. + */ + nscoord GetAdvanceWidth() const; + + /** + * Returns the index of the character into this rendered run whose + * glyph cell contains the given point, or -1 if there is no such + * character. This does not hit test against any overflow. + * + * @param aContext The context to use for unit conversions. + * @param aPoint The point in the user space of the <text> element. + */ + int32_t GetCharNumAtPosition(nsPresContext* aContext, + const gfxPoint& aPoint) const; + + /** + * The text frame that this rendered run lies within. + */ + nsTextFrame* mFrame; + + /** + * The point in user space that the text is positioned at. + * + * For a horizontal run: + * The x coordinate is the left edge of a LTR run of text or the right edge of + * an RTL run. The y coordinate is the baseline of the text. + * For a vertical run: + * The x coordinate is the baseline of the text. + * The y coordinate is the top edge of a LTR run, or bottom of RTL. + */ + gfxPoint mPosition; + + /** + * The horizontal scale factor to apply when painting glyphs to take + * into account textLength="". + */ + float mLengthAdjustScaleFactor; + + /** + * The rotation in radians in the user coordinate system that the text has. + */ + float mRotate; + + /** + * The scale factor that was used to transform the text run's original font + * size into a sane range for painting and measurement. + */ + double mFontSizeScaleFactor; + + /** + * The baseline in app units of this text run. The measurement is from the + * top of the text frame. (From the left edge if vertical.) + */ + nscoord mBaseline; + + /** + * The offset and length in mFrame's content Text that corresponds to + * this text rendered run. These are original char indexes. + */ + uint32_t mTextFrameContentOffset; + uint32_t mTextFrameContentLength; + + /** + * The character index in the whole SVG <text> element that this text rendered + * run begins at. + */ + uint32_t mTextElementCharIndex; +}; + +gfxMatrix TextRenderedRun::GetTransformFromUserSpaceForPainting( + nsPresContext* aContext, const nscoord aVisIStartEdge, + const nscoord aVisIEndEdge) const { + // We transform to device pixels positioned such that painting the text frame + // at (0,0) with aItem will result in the text being in the right place. + + gfxMatrix m; + if (!mFrame) { + return m; + } + + float cssPxPerDevPx = + nsPresContext::AppUnitsToFloatCSSPixels(aContext->AppUnitsPerDevPixel()); + + // Glyph position in user space. + m.PreTranslate(mPosition / cssPxPerDevPx); + + // Take into account any font size scaling and scaling due to textLength="". + m.PreScale(1.0 / mFontSizeScaleFactor, 1.0 / mFontSizeScaleFactor); + + // Rotation due to rotate="" or a <textPath>. + m.PreRotate(mRotate); + + m.PreScale(mLengthAdjustScaleFactor, 1.0); + + // Translation to get the text frame in the right place. + nsPoint t; + + if (IsVertical()) { + t = nsPoint(-mBaseline, IsRightToLeft() + ? -mFrame->GetRect().height + aVisIEndEdge + : -aVisIStartEdge); + } else { + t = nsPoint(IsRightToLeft() ? -mFrame->GetRect().width + aVisIEndEdge + : -aVisIStartEdge, + -mBaseline); + } + m.PreTranslate(AppUnitsToGfxUnits(t, aContext)); + + return m; +} + +gfxMatrix TextRenderedRun::GetTransformFromRunUserSpaceToUserSpace( + nsPresContext* aContext) const { + gfxMatrix m; + if (!mFrame) { + return m; + } + + float cssPxPerDevPx = + nsPresContext::AppUnitsToFloatCSSPixels(aContext->AppUnitsPerDevPixel()); + + nscoord start, end; + GetClipEdges(start, end); + + // Glyph position in user space. + m.PreTranslate(mPosition); + + // Rotation due to rotate="" or a <textPath>. + m.PreRotate(mRotate); + + // Scale due to textLength="". + m.PreScale(mLengthAdjustScaleFactor, 1.0); + + // Translation to get the text frame in the right place. + nsPoint t; + if (IsVertical()) { + t = nsPoint(-mBaseline, + IsRightToLeft() ? -mFrame->GetRect().height + start + end : 0); + } else { + t = nsPoint(IsRightToLeft() ? -mFrame->GetRect().width + start + end : 0, + -mBaseline); + } + m.PreTranslate(AppUnitsToGfxUnits(t, aContext) * cssPxPerDevPx / + mFontSizeScaleFactor); + + return m; +} + +gfxMatrix TextRenderedRun::GetTransformFromRunUserSpaceToFrameUserSpace( + nsPresContext* aContext) const { + gfxMatrix m; + if (!mFrame) { + return m; + } + + nscoord start, end; + GetClipEdges(start, end); + + // Translate by the horizontal distance into the text frame this + // rendered run is. + gfxFloat appPerCssPx = AppUnitsPerCSSPixel(); + gfxPoint t = IsVertical() ? gfxPoint(0, start / appPerCssPx) + : gfxPoint(start / appPerCssPx, 0); + return m.PreTranslate(t); +} + +SVGBBox TextRenderedRun::GetRunUserSpaceRect(nsPresContext* aContext, + uint32_t aFlags) const { + SVGBBox r; + if (!mFrame) { + return r; + } + + // Determine the amount of overflow above and below the frame's mRect. + // + // We need to call InkOverflowRectRelativeToSelf because this includes + // overflowing decorations, which the MeasureText call below does not. We + // assume here the decorations only overflow above and below the frame, never + // horizontally. + nsRect self = mFrame->InkOverflowRectRelativeToSelf(); + nsRect rect = mFrame->GetRect(); + bool vertical = IsVertical(); + nscoord above = vertical ? -self.x : -self.y; + nscoord below = + vertical ? self.XMost() - rect.width : self.YMost() - rect.height; + + gfxSkipCharsIterator it = mFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxSkipCharsIterator start = it; + gfxTextRun* textRun = mFrame->GetTextRun(nsTextFrame::eInflated); + + // Get the content range for this rendered run. + Range range = ConvertOriginalToSkipped(it, mTextFrameContentOffset, + mTextFrameContentLength); + if (range.Length() == 0) { + return r; + } + + // FIXME(heycam): We could create a single PropertyProvider for all + // TextRenderedRuns that correspond to the text frame, rather than recreate + // it each time here. + nsTextFrame::PropertyProvider provider(mFrame, start); + + // Measure that range. + gfxTextRun::Metrics metrics = textRun->MeasureText( + range, gfxFont::LOOSE_INK_EXTENTS, nullptr, &provider); + // Make sure it includes the font-box. + gfxRect fontBox(0, -metrics.mAscent, metrics.mAdvanceWidth, + metrics.mAscent + metrics.mDescent); + metrics.mBoundingBox.UnionRect(metrics.mBoundingBox, fontBox); + + // Determine the rectangle that covers the rendered run's fill, + // taking into account the measured vertical overflow due to + // decorations. + nscoord baseline = + NSToCoordRoundWithClamp(metrics.mBoundingBox.y + metrics.mAscent); + gfxFloat x, width; + if (aFlags & eNoHorizontalOverflow) { + x = 0.0; + width = textRun->GetAdvanceWidth(range, &provider); + if (width < 0.0) { + x = width; + width = -width; + } + } else { + x = metrics.mBoundingBox.x; + width = metrics.mBoundingBox.width; + } + nsRect fillInAppUnits( + NSToCoordRoundWithClamp(x), baseline - above, + NSToCoordRoundWithClamp(width), + NSToCoordRoundWithClamp(metrics.mBoundingBox.height) + above + below); + if (textRun->IsVertical()) { + // Swap line-relative textMetrics dimensions to physical coordinates. + std::swap(fillInAppUnits.x, fillInAppUnits.y); + std::swap(fillInAppUnits.width, fillInAppUnits.height); + } + + // Convert the app units rectangle to user units. + gfxRect fill = AppUnitsToFloatCSSPixels( + gfxRect(fillInAppUnits.x, fillInAppUnits.y, fillInAppUnits.width, + fillInAppUnits.height), + aContext); + + // Scale the rectangle up due to any mFontSizeScaleFactor. + fill.Scale(1.0 / mFontSizeScaleFactor); + + // Include the fill if requested. + if (aFlags & eIncludeFill) { + r = fill; + } + + // Include the stroke if requested. + if ((aFlags & eIncludeStroke) && !fill.IsEmpty() && + SVGUtils::GetStrokeWidth(mFrame) > 0) { + r.UnionEdges( + SVGUtils::PathExtentsToMaxStrokeExtents(fill, mFrame, gfxMatrix())); + } + + return r; +} + +SVGBBox TextRenderedRun::GetFrameUserSpaceRect(nsPresContext* aContext, + uint32_t aFlags) const { + SVGBBox r = GetRunUserSpaceRect(aContext, aFlags); + if (r.IsEmpty()) { + return r; + } + gfxMatrix m = GetTransformFromRunUserSpaceToFrameUserSpace(aContext); + return m.TransformBounds(r.ToThebesRect()); +} + +SVGBBox TextRenderedRun::GetUserSpaceRect( + nsPresContext* aContext, uint32_t aFlags, + const gfxMatrix* aAdditionalTransform) const { + SVGBBox r = GetRunUserSpaceRect(aContext, aFlags); + if (r.IsEmpty()) { + return r; + } + gfxMatrix m = GetTransformFromRunUserSpaceToUserSpace(aContext); + if (aAdditionalTransform) { + m *= *aAdditionalTransform; + } + return m.TransformBounds(r.ToThebesRect()); +} + +void TextRenderedRun::GetClipEdges(nscoord& aVisIStartEdge, + nscoord& aVisIEndEdge) const { + uint32_t contentLength = mFrame->GetContentLength(); + if (mTextFrameContentOffset == 0 && + mTextFrameContentLength == contentLength) { + // If the rendered run covers the entire content, we know we don't need + // to clip without having to measure anything. + aVisIStartEdge = 0; + aVisIEndEdge = 0; + return; + } + + gfxSkipCharsIterator it = mFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = mFrame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(mFrame, it); + + // Get the covered content offset/length for this rendered run in skipped + // characters, since that is what GetAdvanceWidth expects. + Range runRange = ConvertOriginalToSkipped(it, mTextFrameContentOffset, + mTextFrameContentLength); + + // Get the offset/length of the whole nsTextFrame. + uint32_t frameOffset = mFrame->GetContentOffset(); + uint32_t frameLength = mFrame->GetContentLength(); + + // Trim the whole-nsTextFrame offset/length to remove any leading/trailing + // white space, as the nsTextFrame when painting does not include them when + // interpreting clip edges. + nsTextFrame::TrimmedOffsets trimmedOffsets = + mFrame->GetTrimmedOffsets(mFrame->TextFragment()); + TrimOffsets(frameOffset, frameLength, trimmedOffsets); + + // Convert the trimmed whole-nsTextFrame offset/length into skipped + // characters. + Range frameRange = ConvertOriginalToSkipped(it, frameOffset, frameLength); + + // Measure the advance width in the text run between the start of + // frame's content and the start of the rendered run's content, + nscoord startEdge = textRun->GetAdvanceWidth( + Range(frameRange.start, runRange.start), &provider); + + // and between the end of the rendered run's content and the end + // of the frame's content. + nscoord endEdge = + textRun->GetAdvanceWidth(Range(runRange.end, frameRange.end), &provider); + + if (textRun->IsRightToLeft()) { + aVisIStartEdge = endEdge; + aVisIEndEdge = startEdge; + } else { + aVisIStartEdge = startEdge; + aVisIEndEdge = endEdge; + } +} + +nscoord TextRenderedRun::GetAdvanceWidth() const { + gfxSkipCharsIterator it = mFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = mFrame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(mFrame, it); + + Range range = ConvertOriginalToSkipped(it, mTextFrameContentOffset, + mTextFrameContentLength); + + return textRun->GetAdvanceWidth(range, &provider); +} + +int32_t TextRenderedRun::GetCharNumAtPosition(nsPresContext* aContext, + const gfxPoint& aPoint) const { + if (mTextFrameContentLength == 0) { + return -1; + } + + float cssPxPerDevPx = + nsPresContext::AppUnitsToFloatCSSPixels(aContext->AppUnitsPerDevPixel()); + + // Convert the point from user space into run user space, and take + // into account any mFontSizeScaleFactor. + gfxMatrix m = GetTransformFromRunUserSpaceToUserSpace(aContext); + if (!m.Invert()) { + return -1; + } + gfxPoint p = m.TransformPoint(aPoint) / cssPxPerDevPx * mFontSizeScaleFactor; + + // First check that the point lies vertically between the top and bottom + // edges of the text. + gfxFloat ascent, descent; + GetAscentAndDescentInAppUnits(mFrame, ascent, descent); + + WritingMode writingMode = mFrame->GetWritingMode(); + if (writingMode.IsVertical()) { + gfxFloat leftEdge = mFrame->GetLogicalBaseline(writingMode) - + (writingMode.IsVerticalRL() ? ascent : descent); + gfxFloat rightEdge = leftEdge + ascent + descent; + if (p.x < aContext->AppUnitsToGfxUnits(leftEdge) || + p.x > aContext->AppUnitsToGfxUnits(rightEdge)) { + return -1; + } + } else { + gfxFloat topEdge = mFrame->GetLogicalBaseline(writingMode) - ascent; + gfxFloat bottomEdge = topEdge + ascent + descent; + if (p.y < aContext->AppUnitsToGfxUnits(topEdge) || + p.y > aContext->AppUnitsToGfxUnits(bottomEdge)) { + return -1; + } + } + + gfxSkipCharsIterator it = mFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = mFrame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(mFrame, it); + + // Next check that the point lies horizontally within the left and right + // edges of the text. + Range range = ConvertOriginalToSkipped(it, mTextFrameContentOffset, + mTextFrameContentLength); + gfxFloat runAdvance = + aContext->AppUnitsToGfxUnits(textRun->GetAdvanceWidth(range, &provider)); + + gfxFloat pos = writingMode.IsVertical() ? p.y : p.x; + if (pos < 0 || pos >= runAdvance) { + return -1; + } + + // Finally, measure progressively smaller portions of the rendered run to + // find which glyph it lies within. This will need to change once we + // support letter-spacing and word-spacing. + bool rtl = textRun->IsRightToLeft(); + for (int32_t i = mTextFrameContentLength - 1; i >= 0; i--) { + range = ConvertOriginalToSkipped(it, mTextFrameContentOffset, i); + gfxFloat advance = aContext->AppUnitsToGfxUnits( + textRun->GetAdvanceWidth(range, &provider)); + if ((rtl && pos < runAdvance - advance) || (!rtl && pos >= advance)) { + return i; + } + } + return -1; +} + +// ---------------------------------------------------------------------------- +// TextNodeIterator + +enum SubtreePosition { eBeforeSubtree, eWithinSubtree, eAfterSubtree }; + +/** + * An iterator class for Text that are descendants of a given node, the + * root. Nodes are iterated in document order. An optional subtree can be + * specified, in which case the iterator will track whether the current state of + * the traversal over the tree is within that subtree or is past that subtree. + */ +class TextNodeIterator { + public: + /** + * Constructs a TextNodeIterator with the specified root node and optional + * subtree. + */ + explicit TextNodeIterator(nsIContent* aRoot, nsIContent* aSubtree = nullptr) + : mRoot(aRoot), + mSubtree(aSubtree == aRoot ? nullptr : aSubtree), + mCurrent(aRoot), + mSubtreePosition(mSubtree ? eBeforeSubtree : eWithinSubtree) { + NS_ASSERTION(aRoot, "expected non-null root"); + if (!aRoot->IsText()) { + Next(); + } + } + + /** + * Returns the current Text, or null if the iterator has finished. + */ + Text* Current() const { return mCurrent ? mCurrent->AsText() : nullptr; } + + /** + * Advances to the next Text and returns it, or null if the end of + * iteration has been reached. + */ + Text* Next(); + + /** + * Returns whether the iterator is currently within the subtree rooted + * at mSubtree. Returns true if we are not tracking a subtree (we consider + * that we're always within the subtree). + */ + bool IsWithinSubtree() const { return mSubtreePosition == eWithinSubtree; } + + /** + * Returns whether the iterator is past the subtree rooted at mSubtree. + * Returns false if we are not tracking a subtree. + */ + bool IsAfterSubtree() const { return mSubtreePosition == eAfterSubtree; } + + private: + /** + * The root under which all Text will be iterated over. + */ + nsIContent* const mRoot; + + /** + * The node rooting the subtree to track. + */ + nsIContent* const mSubtree; + + /** + * The current node during iteration. + */ + nsIContent* mCurrent; + + /** + * The current iterator position relative to mSubtree. + */ + SubtreePosition mSubtreePosition; +}; + +Text* TextNodeIterator::Next() { + // Starting from mCurrent, we do a non-recursive traversal to the next + // Text beneath mRoot, updating mSubtreePosition appropriately if we + // encounter mSubtree. + if (mCurrent) { + do { + nsIContent* next = + IsTextContentElement(mCurrent) ? mCurrent->GetFirstChild() : nullptr; + if (next) { + mCurrent = next; + if (mCurrent == mSubtree) { + mSubtreePosition = eWithinSubtree; + } + } else { + for (;;) { + if (mCurrent == mRoot) { + mCurrent = nullptr; + break; + } + if (mCurrent == mSubtree) { + mSubtreePosition = eAfterSubtree; + } + next = mCurrent->GetNextSibling(); + if (next) { + mCurrent = next; + if (mCurrent == mSubtree) { + mSubtreePosition = eWithinSubtree; + } + break; + } + if (mCurrent == mSubtree) { + mSubtreePosition = eAfterSubtree; + } + mCurrent = mCurrent->GetParent(); + } + } + } while (mCurrent && !mCurrent->IsText()); + } + + return mCurrent ? mCurrent->AsText() : nullptr; +} + +// ---------------------------------------------------------------------------- +// TextNodeCorrespondenceRecorder + +/** + * TextNodeCorrespondence is used as the value of a frame property that + * is stored on all its descendant nsTextFrames. It stores the number of DOM + * characters between it and the previous nsTextFrame that did not have an + * nsTextFrame created for them, due to either not being in a correctly + * parented text content element, or because they were display:none. + * These are called "undisplayed characters". + * + * See also TextNodeCorrespondenceRecorder below, which is what sets the + * frame property. + */ +struct TextNodeCorrespondence { + explicit TextNodeCorrespondence(uint32_t aUndisplayedCharacters) + : mUndisplayedCharacters(aUndisplayedCharacters) {} + + uint32_t mUndisplayedCharacters; +}; + +NS_DECLARE_FRAME_PROPERTY_DELETABLE(TextNodeCorrespondenceProperty, + TextNodeCorrespondence) + +/** + * Returns the number of undisplayed characters before the specified + * nsTextFrame. + */ +static uint32_t GetUndisplayedCharactersBeforeFrame(nsTextFrame* aFrame) { + void* value = aFrame->GetProperty(TextNodeCorrespondenceProperty()); + TextNodeCorrespondence* correspondence = + static_cast<TextNodeCorrespondence*>(value); + if (!correspondence) { + // FIXME bug 903785 + NS_ERROR( + "expected a TextNodeCorrespondenceProperty on nsTextFrame " + "used for SVG text"); + return 0; + } + return correspondence->mUndisplayedCharacters; +} + +/** + * Traverses the nsTextFrames for an SVGTextFrame and records a + * TextNodeCorrespondenceProperty on each for the number of undisplayed DOM + * characters between each frame. This is done by iterating simultaneously + * over the Text and nsTextFrames and noting when Text (or + * parts of them) are skipped when finding the next nsTextFrame. + */ +class TextNodeCorrespondenceRecorder { + public: + /** + * Entry point for the TextNodeCorrespondenceProperty recording. + */ + static void RecordCorrespondence(SVGTextFrame* aRoot); + + private: + explicit TextNodeCorrespondenceRecorder(SVGTextFrame* aRoot) + : mNodeIterator(aRoot->GetContent()), + mPreviousNode(nullptr), + mNodeCharIndex(0) {} + + void Record(SVGTextFrame* aRoot); + void TraverseAndRecord(nsIFrame* aFrame); + + /** + * Returns the next non-empty Text. + */ + Text* NextNode(); + + /** + * The iterator over the Text that we use as we simultaneously + * iterate over the nsTextFrames. + */ + TextNodeIterator mNodeIterator; + + /** + * The previous Text we iterated over. + */ + Text* mPreviousNode; + + /** + * The index into the current Text's character content. + */ + uint32_t mNodeCharIndex; +}; + +/* static */ +void TextNodeCorrespondenceRecorder::RecordCorrespondence(SVGTextFrame* aRoot) { + if (aRoot->HasAnyStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY)) { + // Resolve bidi so that continuation frames are created if necessary: + aRoot->MaybeResolveBidiForAnonymousBlockChild(); + TextNodeCorrespondenceRecorder recorder(aRoot); + recorder.Record(aRoot); + aRoot->RemoveStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY); + } +} + +void TextNodeCorrespondenceRecorder::Record(SVGTextFrame* aRoot) { + if (!mNodeIterator.Current()) { + // If there are no Text nodes then there is nothing to do. + return; + } + + // Traverse over all the nsTextFrames and record the number of undisplayed + // characters. + TraverseAndRecord(aRoot); + + // Find how many undisplayed characters there are after the final nsTextFrame. + uint32_t undisplayed = 0; + if (mNodeIterator.Current()) { + if (mPreviousNode && mPreviousNode->TextLength() != mNodeCharIndex) { + // The last nsTextFrame ended part way through a Text node. The + // remaining characters count as undisplayed. + NS_ASSERTION(mNodeCharIndex < mPreviousNode->TextLength(), + "incorrect tracking of undisplayed characters in " + "text nodes"); + undisplayed += mPreviousNode->TextLength() - mNodeCharIndex; + } + // All the remaining Text that we iterate must also be undisplayed. + for (Text* textNode = mNodeIterator.Current(); textNode; + textNode = NextNode()) { + undisplayed += textNode->TextLength(); + } + } + + // Record the trailing number of undisplayed characters on the + // SVGTextFrame. + aRoot->mTrailingUndisplayedCharacters = undisplayed; +} + +Text* TextNodeCorrespondenceRecorder::NextNode() { + mPreviousNode = mNodeIterator.Current(); + Text* next; + do { + next = mNodeIterator.Next(); + } while (next && next->TextLength() == 0); + return next; +} + +void TextNodeCorrespondenceRecorder::TraverseAndRecord(nsIFrame* aFrame) { + // Recursively iterate over the frame tree, for frames that correspond + // to text content elements. + if (IsTextContentElement(aFrame->GetContent())) { + for (nsIFrame* f : aFrame->PrincipalChildList()) { + TraverseAndRecord(f); + } + return; + } + + nsTextFrame* frame; // The current text frame. + Text* node; // The text node for the current text frame. + if (!GetNonEmptyTextFrameAndNode(aFrame, frame, node)) { + // If this isn't an nsTextFrame, or is empty, nothing to do. + return; + } + + NS_ASSERTION(frame->GetContentOffset() >= 0, + "don't know how to handle negative content indexes"); + + uint32_t undisplayed = 0; + if (!mPreviousNode) { + // Must be the very first text frame. + NS_ASSERTION(mNodeCharIndex == 0, + "incorrect tracking of undisplayed " + "characters in text nodes"); + if (!mNodeIterator.Current()) { + MOZ_ASSERT_UNREACHABLE( + "incorrect tracking of correspondence between " + "text frames and text nodes"); + } else { + // Each whole Text we find before we get to the text node for the + // first text frame must be undisplayed. + while (mNodeIterator.Current() != node) { + undisplayed += mNodeIterator.Current()->TextLength(); + NextNode(); + } + // If the first text frame starts at a non-zero content offset, then those + // earlier characters are also undisplayed. + undisplayed += frame->GetContentOffset(); + NextNode(); + } + } else if (mPreviousNode == node) { + // Same text node as last time. + if (static_cast<uint32_t>(frame->GetContentOffset()) != mNodeCharIndex) { + // We have some characters in the middle of the text node + // that are undisplayed. + NS_ASSERTION( + mNodeCharIndex < static_cast<uint32_t>(frame->GetContentOffset()), + "incorrect tracking of undisplayed characters in " + "text nodes"); + undisplayed = frame->GetContentOffset() - mNodeCharIndex; + } + } else { + // Different text node from last time. + if (mPreviousNode->TextLength() != mNodeCharIndex) { + NS_ASSERTION(mNodeCharIndex < mPreviousNode->TextLength(), + "incorrect tracking of undisplayed characters in " + "text nodes"); + // Any trailing characters at the end of the previous Text are + // undisplayed. + undisplayed = mPreviousNode->TextLength() - mNodeCharIndex; + } + // Each whole Text we find before we get to the text node for + // the current text frame must be undisplayed. + while (mNodeIterator.Current() && mNodeIterator.Current() != node) { + undisplayed += mNodeIterator.Current()->TextLength(); + NextNode(); + } + // If the current text frame starts at a non-zero content offset, then those + // earlier characters are also undisplayed. + undisplayed += frame->GetContentOffset(); + NextNode(); + } + + // Set the frame property. + frame->SetProperty(TextNodeCorrespondenceProperty(), + new TextNodeCorrespondence(undisplayed)); + + // Remember how far into the current Text we are. + mNodeCharIndex = frame->GetContentEnd(); +} + +// ---------------------------------------------------------------------------- +// TextFrameIterator + +/** + * An iterator class for nsTextFrames that are descendants of an + * SVGTextFrame. The iterator can optionally track whether the + * current nsTextFrame is for a descendant of, or past, a given subtree + * content node or frame. (This functionality is used for example by the SVG + * DOM text methods to get only the nsTextFrames for a particular <tspan>.) + * + * TextFrameIterator also tracks and exposes other information about the + * current nsTextFrame: + * + * * how many undisplayed characters came just before it + * * its position (in app units) relative to the SVGTextFrame's anonymous + * block frame + * * what nsInlineFrame corresponding to a <textPath> element it is a + * descendant of + * * what computed dominant-baseline value applies to it + * + * Note that any text frames that are empty -- whose ContentLength() is 0 -- + * will be skipped over. + */ +class MOZ_STACK_CLASS TextFrameIterator { + public: + /** + * Constructs a TextFrameIterator for the specified SVGTextFrame + * with an optional frame subtree to restrict iterated text frames to. + */ + explicit TextFrameIterator(SVGTextFrame* aRoot, + const nsIFrame* aSubtree = nullptr) + : mRootFrame(aRoot), + mSubtree(aSubtree), + mCurrentFrame(aRoot), + mCurrentPosition(), + mSubtreePosition(mSubtree ? eBeforeSubtree : eWithinSubtree) { + Init(); + } + + /** + * Constructs a TextFrameIterator for the specified SVGTextFrame + * with an optional frame content subtree to restrict iterated text frames to. + */ + TextFrameIterator(SVGTextFrame* aRoot, nsIContent* aSubtree) + : mRootFrame(aRoot), + mSubtree(aRoot && aSubtree && aSubtree != aRoot->GetContent() + ? aSubtree->GetPrimaryFrame() + : nullptr), + mCurrentFrame(aRoot), + mCurrentPosition(), + mSubtreePosition(mSubtree ? eBeforeSubtree : eWithinSubtree) { + Init(); + } + + /** + * Returns the root SVGTextFrame this TextFrameIterator is iterating over. + */ + SVGTextFrame* Root() const { return mRootFrame; } + + /** + * Returns the current nsTextFrame. + */ + nsTextFrame* Current() const { return do_QueryFrame(mCurrentFrame); } + + /** + * Returns the number of undisplayed characters in the DOM just before the + * current frame. + */ + uint32_t UndisplayedCharacters() const; + + /** + * Returns the current frame's position, in app units, relative to the + * root SVGTextFrame's anonymous block frame. + */ + nsPoint Position() const { return mCurrentPosition; } + + /** + * Advances to the next nsTextFrame and returns it. + */ + nsTextFrame* Next(); + + /** + * Returns whether the iterator is within the subtree. + */ + bool IsWithinSubtree() const { return mSubtreePosition == eWithinSubtree; } + + /** + * Returns whether the iterator is past the subtree. + */ + bool IsAfterSubtree() const { return mSubtreePosition == eAfterSubtree; } + + /** + * Returns the frame corresponding to the <textPath> element, if we + * are inside one. + */ + nsIFrame* TextPathFrame() const { + return mTextPathFrames.IsEmpty() + ? nullptr + : mTextPathFrames.ElementAt(mTextPathFrames.Length() - 1); + } + + /** + * Returns the current frame's computed dominant-baseline value. + */ + StyleDominantBaseline DominantBaseline() const { + return mBaselines.ElementAt(mBaselines.Length() - 1); + } + + /** + * Finishes the iterator. + */ + void Close() { mCurrentFrame = nullptr; } + + private: + /** + * Initializes the iterator and advances to the first item. + */ + void Init() { + if (!mRootFrame) { + return; + } + + mBaselines.AppendElement(mRootFrame->StyleSVG()->mDominantBaseline); + Next(); + } + + /** + * Pushes the specified frame's computed dominant-baseline value. + * If the value of the property is "auto", then the parent frame's + * computed value is used. + */ + void PushBaseline(nsIFrame* aNextFrame); + + /** + * Pops the current dominant-baseline off the stack. + */ + void PopBaseline(); + + /** + * The root frame we are iterating through. + */ + SVGTextFrame* const mRootFrame; + + /** + * The frame for the subtree we are also interested in tracking. + */ + const nsIFrame* const mSubtree; + + /** + * The current value of the iterator. + */ + nsIFrame* mCurrentFrame; + + /** + * The position, in app units, of the current frame relative to mRootFrame. + */ + nsPoint mCurrentPosition; + + /** + * Stack of frames corresponding to <textPath> elements that are in scope + * for the current frame. + */ + AutoTArray<nsIFrame*, 1> mTextPathFrames; + + /** + * Stack of dominant-baseline values to record as we traverse through the + * frame tree. + */ + AutoTArray<StyleDominantBaseline, 8> mBaselines; + + /** + * The iterator's current position relative to mSubtree. + */ + SubtreePosition mSubtreePosition; +}; + +uint32_t TextFrameIterator::UndisplayedCharacters() const { + MOZ_ASSERT( + !mRootFrame->HasAnyStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY), + "Text correspondence must be up to date"); + + if (!mCurrentFrame) { + return mRootFrame->mTrailingUndisplayedCharacters; + } + + nsTextFrame* frame = do_QueryFrame(mCurrentFrame); + return GetUndisplayedCharactersBeforeFrame(frame); +} + +nsTextFrame* TextFrameIterator::Next() { + // Starting from mCurrentFrame, we do a non-recursive traversal to the next + // nsTextFrame beneath mRoot, updating mSubtreePosition appropriately if we + // encounter mSubtree. + if (mCurrentFrame) { + do { + nsIFrame* next = IsTextContentElement(mCurrentFrame->GetContent()) + ? mCurrentFrame->PrincipalChildList().FirstChild() + : nullptr; + if (next) { + // Descend into this frame, and accumulate its position. + mCurrentPosition += next->GetPosition(); + if (next->GetContent()->IsSVGElement(nsGkAtoms::textPath)) { + // Record this <textPath> frame. + mTextPathFrames.AppendElement(next); + } + // Record the frame's baseline. + PushBaseline(next); + mCurrentFrame = next; + if (mCurrentFrame == mSubtree) { + // If the current frame is mSubtree, we have now moved into it. + mSubtreePosition = eWithinSubtree; + } + } else { + for (;;) { + // We want to move past the current frame. + if (mCurrentFrame == mRootFrame) { + // If we've reached the root frame, we're finished. + mCurrentFrame = nullptr; + break; + } + // Remove the current frame's position. + mCurrentPosition -= mCurrentFrame->GetPosition(); + if (mCurrentFrame->GetContent()->IsSVGElement(nsGkAtoms::textPath)) { + // Pop off the <textPath> frame if this is a <textPath>. + mTextPathFrames.RemoveLastElement(); + } + // Pop off the current baseline. + PopBaseline(); + if (mCurrentFrame == mSubtree) { + // If this was mSubtree, we have now moved past it. + mSubtreePosition = eAfterSubtree; + } + next = mCurrentFrame->GetNextSibling(); + if (next) { + // Moving to the next sibling. + mCurrentPosition += next->GetPosition(); + if (next->GetContent()->IsSVGElement(nsGkAtoms::textPath)) { + // Record this <textPath> frame. + mTextPathFrames.AppendElement(next); + } + // Record the frame's baseline. + PushBaseline(next); + mCurrentFrame = next; + if (mCurrentFrame == mSubtree) { + // If the current frame is mSubtree, we have now moved into it. + mSubtreePosition = eWithinSubtree; + } + break; + } + if (mCurrentFrame == mSubtree) { + // If there is no next sibling frame, and the current frame is + // mSubtree, we have now moved past it. + mSubtreePosition = eAfterSubtree; + } + // Ascend out of this frame. + mCurrentFrame = mCurrentFrame->GetParent(); + } + } + } while (mCurrentFrame && !IsNonEmptyTextFrame(mCurrentFrame)); + } + + return Current(); +} + +void TextFrameIterator::PushBaseline(nsIFrame* aNextFrame) { + StyleDominantBaseline baseline = aNextFrame->StyleSVG()->mDominantBaseline; + mBaselines.AppendElement(baseline); +} + +void TextFrameIterator::PopBaseline() { + NS_ASSERTION(!mBaselines.IsEmpty(), "popped too many baselines"); + mBaselines.RemoveLastElement(); +} + +// ----------------------------------------------------------------------------- +// TextRenderedRunIterator + +/** + * Iterator for TextRenderedRun objects for the SVGTextFrame. + */ +class TextRenderedRunIterator { + public: + /** + * Values for the aFilter argument of the constructor, to indicate which + * frames we should be limited to iterating TextRenderedRun objects for. + */ + enum RenderedRunFilter { + // Iterate TextRenderedRuns for all nsTextFrames. + eAllFrames, + // Iterate only TextRenderedRuns for nsTextFrames that are + // visibility:visible. + eVisibleFrames + }; + + /** + * Constructs a TextRenderedRunIterator with an optional frame subtree to + * restrict iterated rendered runs to. + * + * @param aSVGTextFrame The SVGTextFrame whose rendered runs to iterate + * through. + * @param aFilter Indicates whether to iterate rendered runs for non-visible + * nsTextFrames. + * @param aSubtree An optional frame subtree to restrict iterated rendered + * runs to. + */ + explicit TextRenderedRunIterator(SVGTextFrame* aSVGTextFrame, + RenderedRunFilter aFilter = eAllFrames, + const nsIFrame* aSubtree = nullptr) + : mFrameIterator(FrameIfAnonymousChildReflowed(aSVGTextFrame), aSubtree), + mFilter(aFilter), + mTextElementCharIndex(0), + mFrameStartTextElementCharIndex(0), + mFontSizeScaleFactor(aSVGTextFrame->mFontSizeScaleFactor), + mCurrent(First()) {} + + /** + * Constructs a TextRenderedRunIterator with a content subtree to restrict + * iterated rendered runs to. + * + * @param aSVGTextFrame The SVGTextFrame whose rendered runs to iterate + * through. + * @param aFilter Indicates whether to iterate rendered runs for non-visible + * nsTextFrames. + * @param aSubtree A content subtree to restrict iterated rendered runs to. + */ + TextRenderedRunIterator(SVGTextFrame* aSVGTextFrame, + RenderedRunFilter aFilter, nsIContent* aSubtree) + : mFrameIterator(FrameIfAnonymousChildReflowed(aSVGTextFrame), aSubtree), + mFilter(aFilter), + mTextElementCharIndex(0), + mFrameStartTextElementCharIndex(0), + mFontSizeScaleFactor(aSVGTextFrame->mFontSizeScaleFactor), + mCurrent(First()) {} + + /** + * Returns the current TextRenderedRun. + */ + TextRenderedRun Current() const { return mCurrent; } + + /** + * Advances to the next TextRenderedRun and returns it. + */ + TextRenderedRun Next(); + + private: + /** + * Returns the root SVGTextFrame this iterator is for. + */ + SVGTextFrame* Root() const { return mFrameIterator.Root(); } + + /** + * Advances to the first TextRenderedRun and returns it. + */ + TextRenderedRun First(); + + /** + * The frame iterator to use. + */ + TextFrameIterator mFrameIterator; + + /** + * The filter indicating which TextRenderedRuns to return. + */ + RenderedRunFilter mFilter; + + /** + * The character index across the entire <text> element we are currently + * up to. + */ + uint32_t mTextElementCharIndex; + + /** + * The character index across the entire <text> for the start of the current + * frame. + */ + uint32_t mFrameStartTextElementCharIndex; + + /** + * The font-size scale factor we used when constructing the nsTextFrames. + */ + double mFontSizeScaleFactor; + + /** + * The current TextRenderedRun. + */ + TextRenderedRun mCurrent; +}; + +TextRenderedRun TextRenderedRunIterator::Next() { + if (!mFrameIterator.Current()) { + // If there are no more frames, then there are no more rendered runs to + // return. + mCurrent = TextRenderedRun(); + return mCurrent; + } + + // The values we will use to initialize the TextRenderedRun with. + nsTextFrame* frame; + gfxPoint pt; + double rotate; + nscoord baseline; + uint32_t offset, length; + uint32_t charIndex; + + // We loop, because we want to skip over rendered runs that either aren't + // within our subtree of interest, because they don't match the filter, + // or because they are hidden due to having fallen off the end of a + // <textPath>. + for (;;) { + if (mFrameIterator.IsAfterSubtree()) { + mCurrent = TextRenderedRun(); + return mCurrent; + } + + frame = mFrameIterator.Current(); + + charIndex = mTextElementCharIndex; + + // Find the end of the rendered run, by looking through the + // SVGTextFrame's positions array until we find one that is recorded + // as a run boundary. + uint32_t runStart, + runEnd; // XXX Replace runStart with mTextElementCharIndex. + runStart = mTextElementCharIndex; + runEnd = runStart + 1; + while (runEnd < Root()->mPositions.Length() && + !Root()->mPositions[runEnd].mRunBoundary) { + runEnd++; + } + + // Convert the global run start/end indexes into an offset/length into the + // current frame's Text. + offset = + frame->GetContentOffset() + runStart - mFrameStartTextElementCharIndex; + length = runEnd - runStart; + + // If the end of the frame's content comes before the run boundary we found + // in SVGTextFrame's position array, we need to shorten the rendered run. + uint32_t contentEnd = frame->GetContentEnd(); + if (offset + length > contentEnd) { + length = contentEnd - offset; + } + + NS_ASSERTION(offset >= uint32_t(frame->GetContentOffset()), + "invalid offset"); + NS_ASSERTION(offset + length <= contentEnd, "invalid offset or length"); + + // Get the frame's baseline position. + frame->EnsureTextRun(nsTextFrame::eInflated); + baseline = GetBaselinePosition( + frame, frame->GetTextRun(nsTextFrame::eInflated), + mFrameIterator.DominantBaseline(), mFontSizeScaleFactor); + + // Trim the offset/length to remove any leading/trailing white space. + uint32_t untrimmedOffset = offset; + uint32_t untrimmedLength = length; + nsTextFrame::TrimmedOffsets trimmedOffsets = + frame->GetTrimmedOffsets(frame->TextFragment()); + TrimOffsets(offset, length, trimmedOffsets); + charIndex += offset - untrimmedOffset; + + // Get the position and rotation of the character that begins this + // rendered run. + pt = Root()->mPositions[charIndex].mPosition; + rotate = Root()->mPositions[charIndex].mAngle; + + // Determine if we should skip this rendered run. + bool skip = !mFrameIterator.IsWithinSubtree() || + Root()->mPositions[mTextElementCharIndex].mHidden; + if (mFilter == eVisibleFrames) { + skip = skip || !frame->StyleVisibility()->IsVisible(); + } + + // Update our global character index to move past the characters + // corresponding to this rendered run. + mTextElementCharIndex += untrimmedLength; + + // If we have moved past the end of the current frame's content, we need to + // advance to the next frame. + if (offset + untrimmedLength >= contentEnd) { + mFrameIterator.Next(); + mTextElementCharIndex += mFrameIterator.UndisplayedCharacters(); + mFrameStartTextElementCharIndex = mTextElementCharIndex; + } + + if (!mFrameIterator.Current()) { + if (skip) { + // That was the last frame, and we skipped this rendered run. So we + // have no rendered run to return. + mCurrent = TextRenderedRun(); + return mCurrent; + } + break; + } + + if (length && !skip) { + // Only return a rendered run if it didn't get collapsed away entirely + // (due to it being all white space) and if we don't want to skip it. + break; + } + } + + mCurrent = TextRenderedRun(frame, pt, Root()->mLengthAdjustScaleFactor, + rotate, mFontSizeScaleFactor, baseline, offset, + length, charIndex); + return mCurrent; +} + +TextRenderedRun TextRenderedRunIterator::First() { + if (!mFrameIterator.Current()) { + return TextRenderedRun(); + } + + if (Root()->mPositions.IsEmpty()) { + mFrameIterator.Close(); + return TextRenderedRun(); + } + + // Get the character index for the start of this rendered run, by skipping + // any undisplayed characters. + mTextElementCharIndex = mFrameIterator.UndisplayedCharacters(); + mFrameStartTextElementCharIndex = mTextElementCharIndex; + + return Next(); +} + +// ----------------------------------------------------------------------------- +// CharIterator + +/** + * Iterator for characters within an SVGTextFrame. + */ +class MOZ_STACK_CLASS CharIterator { + using Range = gfxTextRun::Range; + + public: + /** + * Values for the aFilter argument of the constructor, to indicate which + * characters we should be iterating over. + */ + enum CharacterFilter { + // Iterate over all original characters from the DOM that are within valid + // text content elements. + eOriginal, + // Iterate only over characters that are not skipped characters. + eUnskipped, + // Iterate only over characters that are addressable by the positioning + // attributes x="", y="", etc. This includes all characters after + // collapsing white space as required by the value of 'white-space'. + eAddressable, + }; + + /** + * Constructs a CharIterator. + * + * @param aSVGTextFrame The SVGTextFrame whose characters to iterate + * through. + * @param aFilter Indicates which characters to iterate over. + * @param aSubtree A content subtree to track whether the current character + * is within. + */ + CharIterator(SVGTextFrame* aSVGTextFrame, CharacterFilter aFilter, + nsIContent* aSubtree, bool aPostReflow = true); + + /** + * Returns whether the iterator is finished. + */ + bool AtEnd() const { return !mFrameIterator.Current(); } + + /** + * Advances to the next matching character. Returns true if there was a + * character to advance to, and false otherwise. + */ + bool Next(); + + /** + * Advances ahead aCount matching characters. Returns true if there were + * enough characters to advance past, and false otherwise. + */ + bool Next(uint32_t aCount); + + /** + * Advances ahead up to aCount matching characters. + */ + void NextWithinSubtree(uint32_t aCount); + + /** + * Advances to the character with the specified index. The index is in the + * space of original characters (i.e., all DOM characters under the <text> + * that are within valid text content elements). + */ + bool AdvanceToCharacter(uint32_t aTextElementCharIndex); + + /** + * Advances to the first matching character after the current nsTextFrame. + */ + bool AdvancePastCurrentFrame(); + + /** + * Advances to the first matching character after the frames within + * the current <textPath>. + */ + bool AdvancePastCurrentTextPathFrame(); + + /** + * Advances to the first matching character of the subtree. Returns true + * if we successfully advance to the subtree, or if we are already within + * the subtree. Returns false if we are past the subtree. + */ + bool AdvanceToSubtree(); + + /** + * Returns the nsTextFrame for the current character. + */ + nsTextFrame* TextFrame() const { return mFrameIterator.Current(); } + + /** + * Returns whether the iterator is within the subtree. + */ + bool IsWithinSubtree() const { return mFrameIterator.IsWithinSubtree(); } + + /** + * Returns whether the iterator is past the subtree. + */ + bool IsAfterSubtree() const { return mFrameIterator.IsAfterSubtree(); } + + /** + * Returns whether the current character is a skipped character. + */ + bool IsOriginalCharSkipped() const { + return mSkipCharsIterator.IsOriginalCharSkipped(); + } + + /** + * Returns whether the current character is the start of a cluster and + * ligature group. + */ + bool IsClusterAndLigatureGroupStart() const { + return mTextRun->IsLigatureGroupStart( + mSkipCharsIterator.GetSkippedOffset()) && + mTextRun->IsClusterStart(mSkipCharsIterator.GetSkippedOffset()); + } + + /** + * Returns the glyph run for the current character. + */ + const gfxTextRun::GlyphRun& GlyphRun() const { + return *mTextRun->FindFirstGlyphRunContaining( + mSkipCharsIterator.GetSkippedOffset()); + } + + /** + * Returns whether the current character is trimmed away when painting, + * due to it being leading/trailing white space. + */ + bool IsOriginalCharTrimmed() const; + + /** + * Returns whether the current character is unaddressable from the SVG glyph + * positioning attributes. + */ + bool IsOriginalCharUnaddressable() const { + return IsOriginalCharSkipped() || IsOriginalCharTrimmed(); + } + + /** + * Returns the text run for the current character. + */ + gfxTextRun* TextRun() const { return mTextRun; } + + /** + * Returns the current character index. + */ + uint32_t TextElementCharIndex() const { return mTextElementCharIndex; } + + /** + * Returns the character index for the start of the cluster/ligature group it + * is part of. + */ + uint32_t GlyphStartTextElementCharIndex() const { + return mGlyphStartTextElementCharIndex; + } + + /** + * Gets the advance, in user units, of the current character. If the + * character is a part of ligature, then the advance returned will be + * a fraction of the ligature glyph's advance. + * + * @param aContext The context to use for unit conversions. + */ + gfxFloat GetAdvance(nsPresContext* aContext) const; + + /** + * Returns the frame corresponding to the <textPath> that the current + * character is within. + */ + nsIFrame* TextPathFrame() const { return mFrameIterator.TextPathFrame(); } + +#ifdef DEBUG + /** + * Returns the subtree we were constructed with. + */ + nsIContent* GetSubtree() const { return mSubtree; } + + /** + * Returns the CharacterFilter mode in use. + */ + CharacterFilter Filter() const { return mFilter; } +#endif + + private: + /** + * Advances to the next character without checking it against the filter. + * Returns true if there was a next character to advance to, or false + * otherwise. + */ + bool NextCharacter(); + + /** + * Returns whether the current character matches the filter. + */ + bool MatchesFilter() const; + + /** + * If this is the start of a glyph, record it. + */ + void UpdateGlyphStartTextElementCharIndex() { + if (!IsOriginalCharSkipped() && IsClusterAndLigatureGroupStart()) { + mGlyphStartTextElementCharIndex = mTextElementCharIndex; + } + } + + /** + * The filter to use. + */ + CharacterFilter mFilter; + + /** + * The iterator for text frames. + */ + TextFrameIterator mFrameIterator; + +#ifdef DEBUG + /** + * The subtree we were constructed with. + */ + nsIContent* const mSubtree; +#endif + + /** + * A gfxSkipCharsIterator for the text frame the current character is + * a part of. + */ + gfxSkipCharsIterator mSkipCharsIterator; + + // Cache for information computed by IsOriginalCharTrimmed. + mutable nsTextFrame* mFrameForTrimCheck; + mutable uint32_t mTrimmedOffset; + mutable uint32_t mTrimmedLength; + + /** + * The text run the current character is a part of. + */ + gfxTextRun* mTextRun; + + /** + * The current character's index. + */ + uint32_t mTextElementCharIndex; + + /** + * The index of the character that starts the cluster/ligature group the + * current character is a part of. + */ + uint32_t mGlyphStartTextElementCharIndex; + + /** + * The scale factor to apply to glyph advances returned by + * GetAdvance etc. to take into account textLength="". + */ + float mLengthAdjustScaleFactor; + + /** + * Whether the instance of this class is being used after reflow has occurred + * or not. + */ + bool mPostReflow; +}; + +CharIterator::CharIterator(SVGTextFrame* aSVGTextFrame, + CharIterator::CharacterFilter aFilter, + nsIContent* aSubtree, bool aPostReflow) + : mFilter(aFilter), + mFrameIterator(aSVGTextFrame, aSubtree), +#ifdef DEBUG + mSubtree(aSubtree), +#endif + mFrameForTrimCheck(nullptr), + mTrimmedOffset(0), + mTrimmedLength(0), + mTextRun(nullptr), + mTextElementCharIndex(0), + mGlyphStartTextElementCharIndex(0), + mLengthAdjustScaleFactor(aSVGTextFrame->mLengthAdjustScaleFactor), + mPostReflow(aPostReflow) { + if (!AtEnd()) { + mSkipCharsIterator = TextFrame()->EnsureTextRun(nsTextFrame::eInflated); + mTextRun = TextFrame()->GetTextRun(nsTextFrame::eInflated); + mTextElementCharIndex = mFrameIterator.UndisplayedCharacters(); + UpdateGlyphStartTextElementCharIndex(); + if (!MatchesFilter()) { + Next(); + } + } +} + +bool CharIterator::Next() { + while (NextCharacter()) { + if (MatchesFilter()) { + return true; + } + } + return false; +} + +bool CharIterator::Next(uint32_t aCount) { + if (aCount == 0 && AtEnd()) { + return false; + } + while (aCount) { + if (!Next()) { + return false; + } + aCount--; + } + return true; +} + +void CharIterator::NextWithinSubtree(uint32_t aCount) { + while (IsWithinSubtree() && aCount) { + --aCount; + if (!Next()) { + return; + } + } +} + +bool CharIterator::AdvanceToCharacter(uint32_t aTextElementCharIndex) { + while (mTextElementCharIndex < aTextElementCharIndex) { + if (!Next()) { + return false; + } + } + return true; +} + +bool CharIterator::AdvancePastCurrentFrame() { + // XXX Can do this better than one character at a time if it matters. + nsTextFrame* currentFrame = TextFrame(); + do { + if (!Next()) { + return false; + } + } while (TextFrame() == currentFrame); + return true; +} + +bool CharIterator::AdvancePastCurrentTextPathFrame() { + nsIFrame* currentTextPathFrame = TextPathFrame(); + NS_ASSERTION(currentTextPathFrame, + "expected AdvancePastCurrentTextPathFrame to be called only " + "within a text path frame"); + do { + if (!AdvancePastCurrentFrame()) { + return false; + } + } while (TextPathFrame() == currentTextPathFrame); + return true; +} + +bool CharIterator::AdvanceToSubtree() { + while (!IsWithinSubtree()) { + if (IsAfterSubtree()) { + return false; + } + if (!AdvancePastCurrentFrame()) { + return false; + } + } + return true; +} + +bool CharIterator::IsOriginalCharTrimmed() const { + if (mFrameForTrimCheck != TextFrame()) { + // Since we do a lot of trim checking, we cache the trimmed offsets and + // lengths while we are in the same frame. + mFrameForTrimCheck = TextFrame(); + uint32_t offset = mFrameForTrimCheck->GetContentOffset(); + uint32_t length = mFrameForTrimCheck->GetContentLength(); + nsTextFrame::TrimmedOffsets trim = mFrameForTrimCheck->GetTrimmedOffsets( + mFrameForTrimCheck->TextFragment(), + (mPostReflow ? nsTextFrame::TrimmedOffsetFlags::Default + : nsTextFrame::TrimmedOffsetFlags::NotPostReflow)); + TrimOffsets(offset, length, trim); + mTrimmedOffset = offset; + mTrimmedLength = length; + } + + // A character is trimmed if it is outside the mTrimmedOffset/mTrimmedLength + // range and it is not a significant newline character. + uint32_t index = mSkipCharsIterator.GetOriginalOffset(); + return !( + (index >= mTrimmedOffset && index < mTrimmedOffset + mTrimmedLength) || + (index >= mTrimmedOffset + mTrimmedLength && + mFrameForTrimCheck->StyleText()->NewlineIsSignificant( + mFrameForTrimCheck) && + mFrameForTrimCheck->TextFragment()->CharAt(index) == '\n')); +} + +gfxFloat CharIterator::GetAdvance(nsPresContext* aContext) const { + float cssPxPerDevPx = + nsPresContext::AppUnitsToFloatCSSPixels(aContext->AppUnitsPerDevPixel()); + + gfxSkipCharsIterator start = + TextFrame()->EnsureTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(TextFrame(), start); + + uint32_t offset = mSkipCharsIterator.GetSkippedOffset(); + gfxFloat advance = + mTextRun->GetAdvanceWidth(Range(offset, offset + 1), &provider); + return aContext->AppUnitsToGfxUnits(advance) * mLengthAdjustScaleFactor * + cssPxPerDevPx; +} + +bool CharIterator::NextCharacter() { + if (AtEnd()) { + return false; + } + + mTextElementCharIndex++; + + // Advance within the current text run. + mSkipCharsIterator.AdvanceOriginal(1); + if (mSkipCharsIterator.GetOriginalOffset() < TextFrame()->GetContentEnd()) { + // We're still within the part of the text run for the current text frame. + UpdateGlyphStartTextElementCharIndex(); + return true; + } + + // Advance to the next frame. + mFrameIterator.Next(); + + // Skip any undisplayed characters. + uint32_t undisplayed = mFrameIterator.UndisplayedCharacters(); + mTextElementCharIndex += undisplayed; + if (!TextFrame()) { + // We're at the end. + mSkipCharsIterator = gfxSkipCharsIterator(); + return false; + } + + mSkipCharsIterator = TextFrame()->EnsureTextRun(nsTextFrame::eInflated); + mTextRun = TextFrame()->GetTextRun(nsTextFrame::eInflated); + UpdateGlyphStartTextElementCharIndex(); + return true; +} + +bool CharIterator::MatchesFilter() const { + switch (mFilter) { + case eOriginal: + return true; + case eUnskipped: + return !IsOriginalCharSkipped(); + case eAddressable: + return !IsOriginalCharSkipped() && !IsOriginalCharUnaddressable(); + } + MOZ_ASSERT_UNREACHABLE("Invalid mFilter value"); + return true; +} + +// ----------------------------------------------------------------------------- +// SVGTextDrawPathCallbacks + +/** + * Text frame draw callback class that paints the text and text decoration parts + * of an nsTextFrame using SVG painting properties, and selection backgrounds + * and decorations as they would normally. + * + * An instance of this class is passed to nsTextFrame::PaintText if painting + * cannot be done directly (e.g. if we are using an SVG pattern fill, stroking + * the text, etc.). + */ +class SVGTextDrawPathCallbacks final : public nsTextFrame::DrawPathCallbacks { + using imgDrawingParams = image::imgDrawingParams; + + public: + /** + * Constructs an SVGTextDrawPathCallbacks. + * + * @param aSVGTextFrame The ancestor text frame. + * @param aContext The context to use for painting. + * @param aFrame The nsTextFrame to paint. + * @param aCanvasTM The transformation matrix to set when painting; this + * should be the FOR_OUTERSVG_TM canvas TM of the text, so that + * paint servers are painted correctly. + * @param aImgParams Whether we need to synchronously decode images. + * @param aShouldPaintSVGGlyphs Whether SVG glyphs should be painted. + */ + SVGTextDrawPathCallbacks(SVGTextFrame* aSVGTextFrame, gfxContext& aContext, + nsTextFrame* aFrame, const gfxMatrix& aCanvasTM, + imgDrawingParams& aImgParams, + bool aShouldPaintSVGGlyphs) + : DrawPathCallbacks(aShouldPaintSVGGlyphs), + mSVGTextFrame(aSVGTextFrame), + mContext(aContext), + mFrame(aFrame), + mCanvasTM(aCanvasTM), + mImgParams(aImgParams), + mColor(0) {} + + void NotifySelectionBackgroundNeedsFill(const Rect& aBackgroundRect, + nscolor aColor, + DrawTarget& aDrawTarget) override; + void PaintDecorationLine(Rect aPath, nscolor aColor) override; + void PaintSelectionDecorationLine(Rect aPath, nscolor aColor) override; + void NotifyBeforeText(nscolor aColor) override; + void NotifyGlyphPathEmitted() override; + void NotifyAfterText() override; + + private: + void SetupContext(); + + bool IsClipPathChild() const { + return mSVGTextFrame->HasAnyStateBits(NS_STATE_SVG_CLIPPATH_CHILD); + } + + /** + * Paints a piece of text geometry. This is called when glyphs + * or text decorations have been emitted to the gfxContext. + */ + void HandleTextGeometry(); + + /** + * Sets the gfxContext paint to the appropriate color or pattern + * for filling text geometry. + */ + void MakeFillPattern(GeneralPattern* aOutPattern); + + /** + * Fills and strokes a piece of text geometry, using group opacity + * if the selection style requires it. + */ + void FillAndStrokeGeometry(); + + /** + * Fills a piece of text geometry. + */ + void FillGeometry(); + + /** + * Strokes a piece of text geometry. + */ + void StrokeGeometry(); + + SVGTextFrame* const mSVGTextFrame; + gfxContext& mContext; + nsTextFrame* const mFrame; + const gfxMatrix& mCanvasTM; + imgDrawingParams& mImgParams; + + /** + * The color that we were last told from one of the path callback functions. + * This color can be the special NS_SAME_AS_FOREGROUND_COLOR, + * NS_40PERCENT_FOREGROUND_COLOR and NS_TRANSPARENT colors when we are + * painting selections or IME decorations. + */ + nscolor mColor; +}; + +void SVGTextDrawPathCallbacks::NotifySelectionBackgroundNeedsFill( + const Rect& aBackgroundRect, nscolor aColor, DrawTarget& aDrawTarget) { + if (IsClipPathChild()) { + // Don't paint selection backgrounds when in a clip path. + return; + } + + mColor = aColor; // currently needed by MakeFillPattern + + GeneralPattern fillPattern; + MakeFillPattern(&fillPattern); + if (fillPattern.GetPattern()) { + DrawOptions drawOptions(aColor == NS_40PERCENT_FOREGROUND_COLOR ? 0.4 + : 1.0); + aDrawTarget.FillRect(aBackgroundRect, fillPattern, drawOptions); + } +} + +void SVGTextDrawPathCallbacks::NotifyBeforeText(nscolor aColor) { + mColor = aColor; + SetupContext(); + mContext.NewPath(); +} + +void SVGTextDrawPathCallbacks::NotifyGlyphPathEmitted() { + HandleTextGeometry(); + mContext.NewPath(); +} + +void SVGTextDrawPathCallbacks::NotifyAfterText() { mContext.Restore(); } + +void SVGTextDrawPathCallbacks::PaintDecorationLine(Rect aPath, nscolor aColor) { + mColor = aColor; + AntialiasMode aaMode = + SVGUtils::ToAntialiasMode(mFrame->StyleText()->mTextRendering); + + mContext.Save(); + mContext.NewPath(); + mContext.SetAntialiasMode(aaMode); + mContext.Rectangle(ThebesRect(aPath)); + HandleTextGeometry(); + mContext.NewPath(); + mContext.Restore(); +} + +void SVGTextDrawPathCallbacks::PaintSelectionDecorationLine(Rect aPath, + nscolor aColor) { + if (IsClipPathChild()) { + // Don't paint selection decorations when in a clip path. + return; + } + + mColor = aColor; + + mContext.Save(); + mContext.NewPath(); + mContext.Rectangle(ThebesRect(aPath)); + FillAndStrokeGeometry(); + mContext.Restore(); +} + +void SVGTextDrawPathCallbacks::SetupContext() { + mContext.Save(); + + // XXX This is copied from nsSVGGlyphFrame::Render, but cairo doesn't actually + // seem to do anything with the antialias mode. So we can perhaps remove it, + // or make SetAntialiasMode set cairo text antialiasing too. + switch (mFrame->StyleText()->mTextRendering) { + case StyleTextRendering::Optimizespeed: + mContext.SetAntialiasMode(AntialiasMode::NONE); + break; + default: + mContext.SetAntialiasMode(AntialiasMode::SUBPIXEL); + break; + } +} + +void SVGTextDrawPathCallbacks::HandleTextGeometry() { + if (IsClipPathChild()) { + RefPtr<Path> path = mContext.GetPath(); + ColorPattern white( + DeviceColor(1.f, 1.f, 1.f, 1.f)); // for masking, so no ToDeviceColor + mContext.GetDrawTarget()->Fill(path, white); + } else { + // Normal painting. + gfxContextMatrixAutoSaveRestore saveMatrix(&mContext); + mContext.SetMatrixDouble(mCanvasTM); + + FillAndStrokeGeometry(); + } +} + +void SVGTextDrawPathCallbacks::MakeFillPattern(GeneralPattern* aOutPattern) { + if (mColor == NS_SAME_AS_FOREGROUND_COLOR || + mColor == NS_40PERCENT_FOREGROUND_COLOR) { + SVGUtils::MakeFillPatternFor(mFrame, &mContext, aOutPattern, mImgParams); + return; + } + + if (mColor == NS_TRANSPARENT) { + return; + } + + aOutPattern->InitColorPattern(ToDeviceColor(mColor)); +} + +void SVGTextDrawPathCallbacks::FillAndStrokeGeometry() { + gfxGroupForBlendAutoSaveRestore autoGroupForBlend(&mContext); + if (mColor == NS_40PERCENT_FOREGROUND_COLOR) { + autoGroupForBlend.PushGroupForBlendBack(gfxContentType::COLOR_ALPHA, 0.4f); + } + + uint32_t paintOrder = mFrame->StyleSVG()->mPaintOrder; + if (!paintOrder) { + FillGeometry(); + StrokeGeometry(); + } else { + while (paintOrder) { + auto component = StylePaintOrder(paintOrder & kPaintOrderMask); + switch (component) { + case StylePaintOrder::Fill: + FillGeometry(); + break; + case StylePaintOrder::Stroke: + StrokeGeometry(); + break; + default: + MOZ_FALLTHROUGH_ASSERT("Unknown paint-order value"); + case StylePaintOrder::Markers: + case StylePaintOrder::Normal: + break; + } + paintOrder >>= kPaintOrderShift; + } + } +} + +void SVGTextDrawPathCallbacks::FillGeometry() { + GeneralPattern fillPattern; + MakeFillPattern(&fillPattern); + if (fillPattern.GetPattern()) { + RefPtr<Path> path = mContext.GetPath(); + FillRule fillRule = SVGUtils::ToFillRule(mFrame->StyleSVG()->mFillRule); + if (fillRule != path->GetFillRule()) { + RefPtr<PathBuilder> builder = path->CopyToBuilder(fillRule); + path = builder->Finish(); + } + mContext.GetDrawTarget()->Fill(path, fillPattern); + } +} + +void SVGTextDrawPathCallbacks::StrokeGeometry() { + // We don't paint the stroke when we are filling with a selection color. + if (mColor == NS_SAME_AS_FOREGROUND_COLOR || + mColor == NS_40PERCENT_FOREGROUND_COLOR) { + if (SVGUtils::HasStroke(mFrame, /*aContextPaint*/ nullptr)) { + GeneralPattern strokePattern; + SVGUtils::MakeStrokePatternFor(mFrame, &mContext, &strokePattern, + mImgParams, /*aContextPaint*/ nullptr); + if (strokePattern.GetPattern()) { + if (!mFrame->GetParent()->GetContent()->IsSVGElement()) { + // The cast that follows would be unsafe + MOZ_ASSERT(false, "Our nsTextFrame's parent's content should be SVG"); + return; + } + SVGElement* svgOwner = + static_cast<SVGElement*>(mFrame->GetParent()->GetContent()); + + // Apply any stroke-specific transform + gfxMatrix outerSVGToUser; + if (SVGUtils::GetNonScalingStrokeTransform(mFrame, &outerSVGToUser) && + outerSVGToUser.Invert()) { + mContext.Multiply(outerSVGToUser); + } + + RefPtr<Path> path = mContext.GetPath(); + SVGContentUtils::AutoStrokeOptions strokeOptions; + SVGContentUtils::GetStrokeOptions(&strokeOptions, svgOwner, + mFrame->Style(), + /*aContextPaint*/ nullptr); + DrawOptions drawOptions; + drawOptions.mAntialiasMode = + SVGUtils::ToAntialiasMode(mFrame->StyleText()->mTextRendering); + mContext.GetDrawTarget()->Stroke(path, strokePattern, strokeOptions); + } + } + } +} + +// ============================================================================ +// SVGTextFrame + +// ---------------------------------------------------------------------------- +// Display list item + +class DisplaySVGText final : public DisplaySVGItem { + public: + DisplaySVGText(nsDisplayListBuilder* aBuilder, SVGTextFrame* aFrame) + : DisplaySVGItem(aBuilder, aFrame) { + MOZ_COUNT_CTOR(DisplaySVGText); + } + + MOZ_COUNTED_DTOR_OVERRIDE(DisplaySVGText) + + NS_DISPLAY_DECL_NAME("DisplaySVGText", TYPE_SVG_TEXT) + + nsDisplayItemGeometry* AllocateGeometry( + nsDisplayListBuilder* aBuilder) override { + return new nsDisplayItemGenericGeometry(this, aBuilder); + } + + nsRect GetComponentAlphaBounds( + nsDisplayListBuilder* aBuilder) const override { + bool snap; + return GetBounds(aBuilder, &snap); + } +}; + +// --------------------------------------------------------------------- +// nsQueryFrame methods + +NS_QUERYFRAME_HEAD(SVGTextFrame) + NS_QUERYFRAME_ENTRY(SVGTextFrame) +NS_QUERYFRAME_TAIL_INHERITING(SVGDisplayContainerFrame) + +} // namespace mozilla + +// --------------------------------------------------------------------- +// Implementation + +nsIFrame* NS_NewSVGTextFrame(mozilla::PresShell* aPresShell, + mozilla::ComputedStyle* aStyle) { + return new (aPresShell) + mozilla::SVGTextFrame(aStyle, aPresShell->GetPresContext()); +} + +namespace mozilla { + +NS_IMPL_FRAMEARENA_HELPERS(SVGTextFrame) + +// --------------------------------------------------------------------- +// nsIFrame methods + +void SVGTextFrame::Init(nsIContent* aContent, nsContainerFrame* aParent, + nsIFrame* aPrevInFlow) { + NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::text), + "Content is not an SVG text"); + + SVGDisplayContainerFrame::Init(aContent, aParent, aPrevInFlow); + AddStateBits(aParent->GetStateBits() & NS_STATE_SVG_CLIPPATH_CHILD); + + mMutationObserver = new MutationObserver(this); + + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + // We're inserting a new <text> element into a non-display context. + // Ensure that we get reflowed. + ScheduleReflowSVGNonDisplayText( + IntrinsicDirty::FrameAncestorsAndDescendants); + } +} + +void SVGTextFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists) { + if (IsSubtreeDirty()) { + // We can sometimes be asked to paint before reflow happens and we + // have updated mPositions, etc. In this case, we just avoid + // painting. + return; + } + if (!IsVisibleForPainting() && aBuilder->IsForPainting()) { + return; + } + DisplayOutline(aBuilder, aLists); + aLists.Content()->AppendNewToTop<DisplaySVGText>(aBuilder, this); +} + +nsresult SVGTextFrame::AttributeChanged(int32_t aNameSpaceID, + nsAtom* aAttribute, int32_t aModType) { + if (aNameSpaceID != kNameSpaceID_None) { + return NS_OK; + } + + if (aAttribute == nsGkAtoms::transform) { + // We don't invalidate for transform changes (the layers code does that). + // Also note that SVGTransformableElement::GetAttributeChangeHint will + // return nsChangeHint_UpdateOverflow for "transform" attribute changes + // and cause DoApplyRenderingChangeToTree to make the SchedulePaint call. + + if (!HasAnyStateBits(NS_FRAME_FIRST_REFLOW) && mCanvasTM && + mCanvasTM->IsSingular()) { + // We won't have calculated the glyph positions correctly. + NotifyGlyphMetricsChange(false); + } + mCanvasTM = nullptr; + } else if (IsGlyphPositioningAttribute(aAttribute) || + aAttribute == nsGkAtoms::textLength || + aAttribute == nsGkAtoms::lengthAdjust) { + NotifyGlyphMetricsChange(false); + } + + return NS_OK; +} + +void SVGTextFrame::ReflowSVGNonDisplayText() { + MOZ_ASSERT(SVGUtils::AnyOuterSVGIsCallingReflowSVG(this), + "only call ReflowSVGNonDisplayText when an outer SVG frame is " + "under ReflowSVG"); + MOZ_ASSERT(HasAnyStateBits(NS_FRAME_IS_NONDISPLAY), + "only call ReflowSVGNonDisplayText if the frame is " + "NS_FRAME_IS_NONDISPLAY"); + + // We had a style change, so we mark this frame as dirty so that the next + // time it is painted, we reflow the anonymous block frame. + this->MarkSubtreeDirty(); + + // Finally, we need to actually reflow the anonymous block frame and update + // mPositions, in case we are being reflowed immediately after a DOM + // mutation that needs frame reconstruction. + MaybeReflowAnonymousBlockChild(); + UpdateGlyphPositioning(); +} + +void SVGTextFrame::ScheduleReflowSVGNonDisplayText(IntrinsicDirty aReason) { + MOZ_ASSERT(!SVGUtils::OuterSVGIsCallingReflowSVG(this), + "do not call ScheduleReflowSVGNonDisplayText when the outer SVG " + "frame is under ReflowSVG"); + MOZ_ASSERT(!HasAnyStateBits(NS_STATE_SVG_TEXT_IN_REFLOW), + "do not call ScheduleReflowSVGNonDisplayText while reflowing the " + "anonymous block child"); + + // We need to find an ancestor frame that we can call FrameNeedsReflow + // on that will cause the document to be marked as needing relayout, + // and for that ancestor (or some further ancestor) to be marked as + // a root to reflow. We choose the closest ancestor frame that is not + // NS_FRAME_IS_NONDISPLAY and which is either an outer SVG frame or a + // non-SVG frame. (We don't consider displayed SVG frame ancestors other + // than SVGOuterSVGFrame, since calling FrameNeedsReflow on those other + // SVG frames would do a bunch of unnecessary work on the SVG frames up to + // the SVGOuterSVGFrame.) + + nsIFrame* f = this; + while (f) { + if (!f->HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + if (f->IsSubtreeDirty()) { + // This is a displayed frame, so if it is already dirty, we will be + // reflowed soon anyway. No need to call FrameNeedsReflow again, then. + return; + } + if (!f->HasAnyStateBits(NS_FRAME_SVG_LAYOUT)) { + break; + } + f->AddStateBits(NS_FRAME_HAS_DIRTY_CHILDREN); + } + f = f->GetParent(); + } + + MOZ_ASSERT(f, "should have found an ancestor frame to reflow"); + + PresShell()->FrameNeedsReflow(f, aReason, NS_FRAME_IS_DIRTY); +} + +NS_IMPL_ISUPPORTS(SVGTextFrame::MutationObserver, nsIMutationObserver) + +void SVGTextFrame::MutationObserver::ContentAppended( + nsIContent* aFirstNewContent) { + mFrame->NotifyGlyphMetricsChange(true); +} + +void SVGTextFrame::MutationObserver::ContentInserted(nsIContent* aChild) { + mFrame->NotifyGlyphMetricsChange(true); +} + +void SVGTextFrame::MutationObserver::ContentRemoved( + nsIContent* aChild, nsIContent* aPreviousSibling) { + mFrame->NotifyGlyphMetricsChange(true); +} + +void SVGTextFrame::MutationObserver::CharacterDataChanged( + nsIContent* aContent, const CharacterDataChangeInfo&) { + mFrame->NotifyGlyphMetricsChange(true); +} + +void SVGTextFrame::MutationObserver::AttributeChanged( + Element* aElement, int32_t aNameSpaceID, nsAtom* aAttribute, + int32_t aModType, const nsAttrValue* aOldValue) { + if (!aElement->IsSVGElement()) { + return; + } + + // Attribute changes on this element will be handled by + // SVGTextFrame::AttributeChanged. + if (aElement == mFrame->GetContent()) { + return; + } + + mFrame->HandleAttributeChangeInDescendant(aElement, aNameSpaceID, aAttribute); +} + +void SVGTextFrame::HandleAttributeChangeInDescendant(Element* aElement, + int32_t aNameSpaceID, + nsAtom* aAttribute) { + if (aElement->IsSVGElement(nsGkAtoms::textPath)) { + if (aNameSpaceID == kNameSpaceID_None && + (aAttribute == nsGkAtoms::startOffset || + aAttribute == nsGkAtoms::path || aAttribute == nsGkAtoms::side_)) { + NotifyGlyphMetricsChange(false); + } else if ((aNameSpaceID == kNameSpaceID_XLink || + aNameSpaceID == kNameSpaceID_None) && + aAttribute == nsGkAtoms::href) { + // Blow away our reference, if any + nsIFrame* childElementFrame = aElement->GetPrimaryFrame(); + if (childElementFrame) { + SVGObserverUtils::RemoveTextPathObserver(childElementFrame); + NotifyGlyphMetricsChange(false); + } + } + } else { + if (aNameSpaceID == kNameSpaceID_None && + IsGlyphPositioningAttribute(aAttribute)) { + NotifyGlyphMetricsChange(false); + } + } +} + +void SVGTextFrame::FindCloserFrameForSelection( + const nsPoint& aPoint, FrameWithDistance* aCurrentBestFrame) { + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + return; + } + + UpdateGlyphPositioning(); + + nsPresContext* presContext = PresContext(); + + // Find the frame that has the closest rendered run rect to aPoint. + TextRenderedRunIterator it(this); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + uint32_t flags = TextRenderedRun::eIncludeFill | + TextRenderedRun::eIncludeStroke | + TextRenderedRun::eNoHorizontalOverflow; + SVGBBox userRect = run.GetUserSpaceRect(presContext, flags); + float devPxPerCSSPx = presContext->CSSPixelsToDevPixels(1.f); + userRect.Scale(devPxPerCSSPx); + + if (!userRect.IsEmpty()) { + gfxMatrix m; + nsRect rect = + SVGUtils::ToCanvasBounds(userRect.ToThebesRect(), m, presContext); + + if (nsLayoutUtils::PointIsCloserToRect(aPoint, rect, + aCurrentBestFrame->mXDistance, + aCurrentBestFrame->mYDistance)) { + aCurrentBestFrame->mFrame = run.mFrame; + } + } + } +} + +//---------------------------------------------------------------------- +// ISVGDisplayableFrame methods + +void SVGTextFrame::NotifySVGChanged(uint32_t aFlags) { + MOZ_ASSERT(aFlags & (TRANSFORM_CHANGED | COORD_CONTEXT_CHANGED), + "Invalidation logic may need adjusting"); + + bool needNewBounds = false; + bool needGlyphMetricsUpdate = false; + bool needNewCanvasTM = false; + + if ((aFlags & COORD_CONTEXT_CHANGED) && + HasAnyStateBits(NS_STATE_SVG_POSITIONING_MAY_USE_PERCENTAGES)) { + needGlyphMetricsUpdate = true; + } + + if (aFlags & TRANSFORM_CHANGED) { + needNewCanvasTM = true; + if (mCanvasTM && mCanvasTM->IsSingular()) { + // We won't have calculated the glyph positions correctly. + needNewBounds = true; + needGlyphMetricsUpdate = true; + } + if (StyleSVGReset()->HasNonScalingStroke()) { + // Stroke currently contributes to our mRect, and our stroke depends on + // the transform to our outer-<svg> if |vector-effect:non-scaling-stroke|. + needNewBounds = true; + } + } + + // If the scale at which we computed our mFontSizeScaleFactor has changed by + // at least a factor of two, reflow the text. This avoids reflowing text + // at every tick of a transform animation, but ensures our glyph metrics + // do not get too far out of sync with the final font size on the screen. + if (needNewCanvasTM && mLastContextScale != 0.0f) { + mCanvasTM = nullptr; + // If we are a non-display frame, then we don't want to call + // GetCanvasTM(), since the context scale does not use it. + gfxMatrix newTM = + HasAnyStateBits(NS_FRAME_IS_NONDISPLAY) ? gfxMatrix() : GetCanvasTM(); + // Compare the old and new context scales. + float scale = GetContextScale(newTM); + float change = scale / mLastContextScale; + if (change >= 2.0f || change <= 0.5f) { + needNewBounds = true; + needGlyphMetricsUpdate = true; + } + } + + if (needNewBounds) { + // Ancestor changes can't affect how we render from the perspective of + // any rendering observers that we may have, so we don't need to + // invalidate them. We also don't need to invalidate ourself, since our + // changed ancestor will have invalidated its entire area, which includes + // our area. + ScheduleReflowSVG(); + } + + if (needGlyphMetricsUpdate) { + // If we are positioned using percentage values we need to update our + // position whenever our viewport's dimensions change. But only do this if + // we have been reflowed once, otherwise the glyph positioning will be + // wrong. (We need to wait until bidi reordering has been done.) + if (!HasAnyStateBits(NS_FRAME_FIRST_REFLOW)) { + NotifyGlyphMetricsChange(false); + } + } +} + +/** + * Gets the offset into a DOM node that the specified caret is positioned at. + */ +static int32_t GetCaretOffset(nsCaret* aCaret) { + RefPtr<Selection> selection = aCaret->GetSelection(); + if (!selection) { + return -1; + } + + return selection->AnchorOffset(); +} + +/** + * Returns whether the caret should be painted for a given TextRenderedRun + * by checking whether the caret is in the range covered by the rendered run. + * + * @param aThisRun The TextRenderedRun to be painted. + * @param aCaret The caret. + */ +static bool ShouldPaintCaret(const TextRenderedRun& aThisRun, nsCaret* aCaret) { + int32_t caretOffset = GetCaretOffset(aCaret); + + if (caretOffset < 0) { + return false; + } + + return uint32_t(caretOffset) >= aThisRun.mTextFrameContentOffset && + uint32_t(caretOffset) < aThisRun.mTextFrameContentOffset + + aThisRun.mTextFrameContentLength; +} + +void SVGTextFrame::PaintSVG(gfxContext& aContext, const gfxMatrix& aTransform, + imgDrawingParams& aImgParams) { + DrawTarget& aDrawTarget = *aContext.GetDrawTarget(); + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (!kid) { + return; + } + + nsPresContext* presContext = PresContext(); + + gfxMatrix initialMatrix = aContext.CurrentMatrixDouble(); + + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + // If we are in a canvas DrawWindow call that used the + // DRAWWINDOW_DO_NOT_FLUSH flag, then we may still have out + // of date frames. Just don't paint anything if they are + // dirty. + if (presContext->PresShell()->InDrawWindowNotFlushing() && + IsSubtreeDirty()) { + return; + } + // Text frames inside <clipPath>, <mask>, etc. will never have had + // ReflowSVG called on them, so call UpdateGlyphPositioning to do this now. + UpdateGlyphPositioning(); + } else if (IsSubtreeDirty()) { + // If we are asked to paint before reflow has recomputed mPositions etc. + // directly via PaintSVG, rather than via a display list, then we need + // to bail out here too. + return; + } + + const float epsilon = 0.0001; + if (abs(mLengthAdjustScaleFactor) < epsilon) { + // A zero scale factor can be caused by having forced the text length to + // zero. In this situation there is nothing to show. + return; + } + + if (aTransform.IsSingular()) { + NS_WARNING("Can't render text element!"); + return; + } + + gfxMatrix matrixForPaintServers = aTransform * initialMatrix; + + // SVG frames' PaintSVG methods paint in CSS px, but normally frames paint in + // dev pixels. Here we multiply a CSS-px-to-dev-pixel factor onto aTransform + // so our non-SVG nsTextFrame children paint correctly. + auto auPerDevPx = presContext->AppUnitsPerDevPixel(); + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels(auPerDevPx); + gfxMatrix canvasTMForChildren = aTransform; + canvasTMForChildren.PreScale(cssPxPerDevPx, cssPxPerDevPx); + initialMatrix.PreScale(1 / cssPxPerDevPx, 1 / cssPxPerDevPx); + + gfxContextMatrixAutoSaveRestore matSR(&aContext); + aContext.NewPath(); + aContext.Multiply(canvasTMForChildren); + gfxMatrix currentMatrix = aContext.CurrentMatrixDouble(); + + RefPtr<nsCaret> caret = presContext->PresShell()->GetCaret(); + nsRect caretRect; + nsIFrame* caretFrame = caret->GetPaintGeometry(&caretRect); + + gfxContextAutoSaveRestore ctxSR; + TextRenderedRunIterator it(this, TextRenderedRunIterator::eVisibleFrames); + TextRenderedRun run = it.Current(); + + SVGContextPaint* outerContextPaint = + SVGContextPaint::GetContextPaint(GetContent()); + + while (run.mFrame) { + nsTextFrame* frame = run.mFrame; + + RefPtr<SVGContextPaintImpl> contextPaint = new SVGContextPaintImpl(); + DrawMode drawMode = contextPaint->Init(&aDrawTarget, initialMatrix, frame, + outerContextPaint, aImgParams); + if (drawMode & DrawMode::GLYPH_STROKE) { + ctxSR.EnsureSaved(&aContext); + // This may change the gfxContext's transform (for non-scaling stroke), + // in which case this needs to happen before we call SetMatrix() below. + SVGUtils::SetupStrokeGeometry(frame->GetParent(), &aContext, + outerContextPaint); + } + + nscoord startEdge, endEdge; + run.GetClipEdges(startEdge, endEdge); + + // Set up the transform for painting the text frame for the substring + // indicated by the run. + gfxMatrix runTransform = run.GetTransformFromUserSpaceForPainting( + presContext, startEdge, endEdge) * + currentMatrix; + aContext.SetMatrixDouble(runTransform); + + if (drawMode != DrawMode(0)) { + bool paintSVGGlyphs; + nsTextFrame::PaintTextParams params(&aContext); + params.framePt = Point(); + params.dirtyRect = + LayoutDevicePixel::FromAppUnits(frame->InkOverflowRect(), auPerDevPx); + params.contextPaint = contextPaint; + bool isSelected; + if (HasAnyStateBits(NS_STATE_SVG_CLIPPATH_CHILD)) { + params.state = nsTextFrame::PaintTextParams::GenerateTextMask; + isSelected = false; + } else { + isSelected = frame->IsSelected(); + } + gfxGroupForBlendAutoSaveRestore autoGroupForBlend(&aContext); + float opacity = 1.0f; + nsIFrame* ancestor = frame->GetParent(); + while (ancestor != this) { + opacity *= ancestor->StyleEffects()->mOpacity; + ancestor = ancestor->GetParent(); + } + if (opacity < 1.0f) { + autoGroupForBlend.PushGroupForBlendBack(gfxContentType::COLOR_ALPHA, + opacity); + } + + if (ShouldRenderAsPath(frame, paintSVGGlyphs)) { + SVGTextDrawPathCallbacks callbacks(this, aContext, frame, + matrixForPaintServers, aImgParams, + paintSVGGlyphs); + params.callbacks = &callbacks; + frame->PaintText(params, startEdge, endEdge, nsPoint(), isSelected); + } else { + frame->PaintText(params, startEdge, endEdge, nsPoint(), isSelected); + } + } + + if (frame == caretFrame && ShouldPaintCaret(run, caret)) { + // XXX Should we be looking at the fill/stroke colours to paint the + // caret with, rather than using the color property? + caret->PaintCaret(aDrawTarget, frame, nsPoint()); + aContext.NewPath(); + } + + run = it.Next(); + } +} + +nsIFrame* SVGTextFrame::GetFrameForPoint(const gfxPoint& aPoint) { + NS_ASSERTION(PrincipalChildList().FirstChild(), "must have a child frame"); + + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + // Text frames inside <clipPath> will never have had ReflowSVG called on + // them, so call UpdateGlyphPositioning to do this now. (Text frames + // inside <mask> and other non-display containers will never need to + // be hit tested.) + UpdateGlyphPositioning(); + } else { + NS_ASSERTION(!IsSubtreeDirty(), "reflow should have happened"); + } + + // Hit-testing any clip-path will typically be a lot quicker than the + // hit-testing of our text frames in the loop below, so we do the former up + // front to avoid unnecessarily wasting cycles on the latter. + if (!SVGUtils::HitTestClip(this, aPoint)) { + return nullptr; + } + + nsPresContext* presContext = PresContext(); + + // Ideally we'd iterate backwards so that we can just return the first frame + // that is under aPoint. In practice this will rarely matter though since it + // is rare for text in/under an SVG <text> element to overlap (i.e. the first + // text frame that is hit will likely be the only text frame that is hit). + + TextRenderedRunIterator it(this); + nsIFrame* hit = nullptr; + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + uint16_t hitTestFlags = SVGUtils::GetGeometryHitTestFlags(run.mFrame); + if (!hitTestFlags) { + continue; + } + + gfxMatrix m = run.GetTransformFromRunUserSpaceToUserSpace(presContext); + if (!m.Invert()) { + return nullptr; + } + + gfxPoint pointInRunUserSpace = m.TransformPoint(aPoint); + gfxRect frameRect = run.GetRunUserSpaceRect( + presContext, TextRenderedRun::eIncludeFill | + TextRenderedRun::eIncludeStroke) + .ToThebesRect(); + + if (Inside(frameRect, pointInRunUserSpace)) { + hit = run.mFrame; + } + } + return hit; +} + +void SVGTextFrame::ReflowSVG() { + MOZ_ASSERT(SVGUtils::AnyOuterSVGIsCallingReflowSVG(this), + "This call is probaby a wasteful mistake"); + + MOZ_ASSERT(!HasAnyStateBits(NS_FRAME_IS_NONDISPLAY), + "ReflowSVG mechanism not designed for this"); + + if (!SVGUtils::NeedsReflowSVG(this)) { + MOZ_ASSERT(!HasAnyStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY | + NS_STATE_SVG_POSITIONING_DIRTY), + "How did this happen?"); + return; + } + + MaybeReflowAnonymousBlockChild(); + UpdateGlyphPositioning(); + + nsPresContext* presContext = PresContext(); + + SVGBBox r; + TextRenderedRunIterator it(this, TextRenderedRunIterator::eAllFrames); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + uint32_t runFlags = 0; + if (!run.mFrame->StyleSVG()->mFill.kind.IsNone()) { + runFlags |= TextRenderedRun::eIncludeFill; + } + if (SVGUtils::HasStroke(run.mFrame)) { + runFlags |= TextRenderedRun::eIncludeStroke; + } + // Our "visual" overflow rect needs to be valid for building display lists + // for hit testing, which means that for certain values of 'pointer-events' + // it needs to include the geometry of the fill or stroke even when the + // fill/ stroke don't actually render (e.g. when stroke="none" or + // stroke-opacity="0"). GetGeometryHitTestFlags accounts for + // 'pointer-events'. The text-shadow is not part of the hit-test area. + uint16_t hitTestFlags = SVGUtils::GetGeometryHitTestFlags(run.mFrame); + if (hitTestFlags & SVG_HIT_TEST_FILL) { + runFlags |= TextRenderedRun::eIncludeFill; + } + if (hitTestFlags & SVG_HIT_TEST_STROKE) { + runFlags |= TextRenderedRun::eIncludeStroke; + } + + if (runFlags) { + r.UnionEdges(run.GetUserSpaceRect(presContext, runFlags)); + } + } + + if (r.IsEmpty()) { + mRect.SetEmpty(); + } else { + mRect = nsLayoutUtils::RoundGfxRectToAppRect(r.ToThebesRect(), + AppUnitsPerCSSPixel()); + + // Due to rounding issues when we have a transform applied, we sometimes + // don't include an additional row of pixels. For now, just inflate our + // covered region. + mRect.Inflate(ceil(presContext->AppUnitsPerDevPixel() / mLastContextScale)); + } + + if (HasAnyStateBits(NS_FRAME_FIRST_REFLOW)) { + // Make sure we have our filter property (if any) before calling + // FinishAndStoreOverflow (subsequent filter changes are handled off + // nsChangeHint_UpdateEffects): + SVGObserverUtils::UpdateEffects(this); + } + + // Now unset the various reflow bits. Do this before calling + // FinishAndStoreOverflow since FinishAndStoreOverflow can require glyph + // positions (to resolve transform-origin). + RemoveStateBits(NS_FRAME_FIRST_REFLOW | NS_FRAME_IS_DIRTY | + NS_FRAME_HAS_DIRTY_CHILDREN); + + nsRect overflow = nsRect(nsPoint(0, 0), mRect.Size()); + OverflowAreas overflowAreas(overflow, overflow); + FinishAndStoreOverflow(overflowAreas, mRect.Size()); +} + +/** + * Converts SVGUtils::eBBox* flags into TextRenderedRun flags appropriate + * for the specified rendered run. + */ +static uint32_t TextRenderedRunFlagsForBBoxContribution( + const TextRenderedRun& aRun, uint32_t aBBoxFlags) { + uint32_t flags = 0; + if ((aBBoxFlags & SVGUtils::eBBoxIncludeFillGeometry) || + ((aBBoxFlags & SVGUtils::eBBoxIncludeFill) && + !aRun.mFrame->StyleSVG()->mFill.kind.IsNone())) { + flags |= TextRenderedRun::eIncludeFill; + } + if ((aBBoxFlags & SVGUtils::eBBoxIncludeStrokeGeometry) || + ((aBBoxFlags & SVGUtils::eBBoxIncludeStroke) && + SVGUtils::HasStroke(aRun.mFrame))) { + flags |= TextRenderedRun::eIncludeStroke; + } + return flags; +} + +SVGBBox SVGTextFrame::GetBBoxContribution(const Matrix& aToBBoxUserspace, + uint32_t aFlags) { + NS_ASSERTION(PrincipalChildList().FirstChild(), "must have a child frame"); + SVGBBox bbox; + + if (aFlags & SVGUtils::eForGetClientRects) { + Rect rect = NSRectToRect(mRect, AppUnitsPerCSSPixel()); + if (!rect.IsEmpty()) { + bbox = aToBBoxUserspace.TransformBounds(rect); + } + return bbox; + } + + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid && kid->IsSubtreeDirty()) { + // Return an empty bbox if our kid's subtree is dirty. This may be called + // in that situation, e.g. when we're building a display list after an + // interrupted reflow. This can also be called during reflow before we've + // been reflowed, e.g. if an earlier sibling is calling + // FinishAndStoreOverflow and needs our parent's perspective matrix, which + // depends on the SVG bbox contribution of this frame. In the latter + // situation, when all siblings have been reflowed, the parent will compute + // its perspective and rerun FinishAndStoreOverflow for all its children. + return bbox; + } + + UpdateGlyphPositioning(); + + nsPresContext* presContext = PresContext(); + + TextRenderedRunIterator it(this); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + uint32_t flags = TextRenderedRunFlagsForBBoxContribution(run, aFlags); + gfxMatrix m = ThebesMatrix(aToBBoxUserspace); + SVGBBox bboxForRun = run.GetUserSpaceRect(presContext, flags, &m); + bbox.UnionEdges(bboxForRun); + } + + return bbox; +} + +//---------------------------------------------------------------------- +// SVGTextFrame SVG DOM methods + +/** + * Returns whether the specified node has any non-empty Text + * beneath it. + */ +static bool HasTextContent(nsIContent* aContent) { + NS_ASSERTION(aContent, "expected non-null aContent"); + + TextNodeIterator it(aContent); + for (Text* text = it.Current(); text; text = it.Next()) { + if (text->TextLength() != 0) { + return true; + } + } + return false; +} + +/** + * Returns the number of DOM characters beneath the specified node. + */ +static uint32_t GetTextContentLength(nsIContent* aContent) { + NS_ASSERTION(aContent, "expected non-null aContent"); + + uint32_t length = 0; + TextNodeIterator it(aContent); + for (Text* text = it.Current(); text; text = it.Next()) { + length += text->TextLength(); + } + return length; +} + +int32_t SVGTextFrame::ConvertTextElementCharIndexToAddressableIndex( + int32_t aIndex, nsIContent* aContent) { + CharIterator it(this, CharIterator::eOriginal, aContent); + if (!it.AdvanceToSubtree()) { + return -1; + } + int32_t result = 0; + int32_t textElementCharIndex; + while (!it.AtEnd() && it.IsWithinSubtree()) { + bool addressable = !it.IsOriginalCharUnaddressable(); + textElementCharIndex = it.TextElementCharIndex(); + it.Next(); + uint32_t delta = it.TextElementCharIndex() - textElementCharIndex; + aIndex -= delta; + if (addressable) { + if (aIndex < 0) { + return result; + } + result += delta; + } + } + return -1; +} + +/** + * Implements the SVG DOM GetNumberOfChars method for the specified + * text content element. + */ +uint32_t SVGTextFrame::GetNumberOfChars(nsIContent* aContent) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + return 0; + } + + UpdateGlyphPositioning(); + + uint32_t n = 0; + CharIterator it(this, CharIterator::eAddressable, aContent); + if (it.AdvanceToSubtree()) { + while (!it.AtEnd() && it.IsWithinSubtree()) { + n++; + it.Next(); + } + } + return n; +} + +/** + * Implements the SVG DOM GetComputedTextLength method for the specified + * text child element. + */ +float SVGTextFrame::GetComputedTextLength(nsIContent* aContent) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + // + // If we ever decide that we need to return accurate values here, + // we could do similar work to GetSubStringLength. + return 0; + } + + UpdateGlyphPositioning(); + + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + PresContext()->AppUnitsPerDevPixel()); + + nscoord length = 0; + TextRenderedRunIterator it(this, TextRenderedRunIterator::eAllFrames, + aContent); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + length += run.GetAdvanceWidth(); + } + + return PresContext()->AppUnitsToGfxUnits(length) * cssPxPerDevPx * + mLengthAdjustScaleFactor / mFontSizeScaleFactor; +} + +/** + * Implements the SVG DOM SelectSubString method for the specified + * text content element. + */ +void SVGTextFrame::SelectSubString(nsIContent* aContent, uint32_t charnum, + uint32_t nchars, ErrorResult& aRv) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + // XXXbz Should this just return without throwing like the no-frame case? + aRv.ThrowInvalidStateError("No layout information available for SVG text"); + return; + } + + UpdateGlyphPositioning(); + + // Convert charnum/nchars from addressable characters relative to + // aContent to global character indices. + CharIterator chit(this, CharIterator::eAddressable, aContent); + if (!chit.AdvanceToSubtree() || !chit.Next(charnum) || + chit.IsAfterSubtree()) { + aRv.ThrowIndexSizeError("Character index out of range"); + return; + } + charnum = chit.TextElementCharIndex(); + const RefPtr<nsIContent> content = chit.TextFrame()->GetContent(); + chit.NextWithinSubtree(nchars); + nchars = chit.TextElementCharIndex() - charnum; + + RefPtr<nsFrameSelection> frameSelection = GetFrameSelection(); + + frameSelection->HandleClick(content, charnum, charnum + nchars, + nsFrameSelection::FocusMode::kCollapseToNewPoint, + CARET_ASSOCIATE_BEFORE); +} + +/** + * For some content we cannot (or currently cannot) compute the length + * without reflowing. In those cases we need to fall back to using + * GetSubStringLengthSlowFallback. + * + * We fall back for textPath since we need glyph positioning in order to + * tell if any characters should be ignored due to having fallen off the + * end of the textPath. + * + * We fall back for bidi because GetTrimmedOffsets does not produce the + * correct results for bidi continuations when passed aPostReflow = false. + * XXX It may be possible to determine which continuations to trim from (and + * which sides), but currently we don't do that. It would require us to + * identify the visual (rather than logical) start and end of the line, to + * avoid trimming at line-internal frame boundaries. Maybe nsBidiPresUtils + * methods like GetFrameToRightOf and GetFrameToLeftOf would help? + * + */ +bool SVGTextFrame::RequiresSlowFallbackForSubStringLength() { + TextFrameIterator frameIter(this); + for (nsTextFrame* frame = frameIter.Current(); frame; + frame = frameIter.Next()) { + if (frameIter.TextPathFrame() || frame->GetNextContinuation()) { + return true; + } + } + return false; +} + +/** + * Implements the SVG DOM GetSubStringLength method for the specified + * text content element. + */ +float SVGTextFrame::GetSubStringLengthFastPath(nsIContent* aContent, + uint32_t charnum, + uint32_t nchars, + ErrorResult& aRv) { + MOZ_ASSERT(!RequiresSlowFallbackForSubStringLength()); + + // We only need our text correspondence to be up to date (no need to call + // UpdateGlyphPositioning). + TextNodeCorrespondenceRecorder::RecordCorrespondence(this); + + // Convert charnum/nchars from addressable characters relative to + // aContent to global character indices. + CharIterator chit(this, CharIterator::eAddressable, aContent, + /* aPostReflow */ false); + if (!chit.AdvanceToSubtree() || !chit.Next(charnum) || + chit.IsAfterSubtree()) { + aRv.ThrowIndexSizeError("Character index out of range"); + return 0; + } + + // We do this after the ThrowIndexSizeError() bit so JS calls correctly throw + // when necessary. + if (nchars == 0) { + return 0.0f; + } + + charnum = chit.TextElementCharIndex(); + chit.NextWithinSubtree(nchars); + nchars = chit.TextElementCharIndex() - charnum; + + // Sum of the substring advances. + nscoord textLength = 0; + + TextFrameIterator frit(this); // aSubtree = nullptr + + // Index of the first non-skipped char in the frame, and of a subsequent char + // that we're interested in. Both are relative to the index of the first + // non-skipped char in the ancestor <text> element. + uint32_t frameStartTextElementCharIndex = 0; + uint32_t textElementCharIndex; + + for (nsTextFrame* frame = frit.Current(); frame; frame = frit.Next()) { + frameStartTextElementCharIndex += frit.UndisplayedCharacters(); + textElementCharIndex = frameStartTextElementCharIndex; + + // Offset into frame's Text: + const uint32_t untrimmedOffset = frame->GetContentOffset(); + const uint32_t untrimmedLength = frame->GetContentEnd() - untrimmedOffset; + + // Trim the offset/length to remove any leading/trailing white space. + uint32_t trimmedOffset = untrimmedOffset; + uint32_t trimmedLength = untrimmedLength; + nsTextFrame::TrimmedOffsets trimmedOffsets = frame->GetTrimmedOffsets( + frame->TextFragment(), nsTextFrame::TrimmedOffsetFlags::NotPostReflow); + TrimOffsets(trimmedOffset, trimmedLength, trimmedOffsets); + + textElementCharIndex += trimmedOffset - untrimmedOffset; + + if (textElementCharIndex >= charnum + nchars) { + break; // we're past the end of the substring + } + + uint32_t offset = textElementCharIndex; + + // Intersect the substring we are interested in with the range covered by + // the nsTextFrame. + IntersectInterval(offset, trimmedLength, charnum, nchars); + + if (trimmedLength != 0) { + // Convert offset into an index into the frame. + offset += trimmedOffset - textElementCharIndex; + + gfxSkipCharsIterator it = frame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = frame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(frame, it); + + Range range = ConvertOriginalToSkipped(it, offset, trimmedLength); + + // Accumulate the advance. + textLength += textRun->GetAdvanceWidth(range, &provider); + } + + // Advance, ready for next call: + frameStartTextElementCharIndex += untrimmedLength; + } + + nsPresContext* presContext = PresContext(); + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + + return presContext->AppUnitsToGfxUnits(textLength) * cssPxPerDevPx / + mFontSizeScaleFactor; +} + +float SVGTextFrame::GetSubStringLengthSlowFallback(nsIContent* aContent, + uint32_t charnum, + uint32_t nchars, + ErrorResult& aRv) { + UpdateGlyphPositioning(); + + // Convert charnum/nchars from addressable characters relative to + // aContent to global character indices. + CharIterator chit(this, CharIterator::eAddressable, aContent); + if (!chit.AdvanceToSubtree() || !chit.Next(charnum) || + chit.IsAfterSubtree()) { + aRv.ThrowIndexSizeError("Character index out of range"); + return 0; + } + + if (nchars == 0) { + return 0.0f; + } + + charnum = chit.TextElementCharIndex(); + chit.NextWithinSubtree(nchars); + nchars = chit.TextElementCharIndex() - charnum; + + // Find each rendered run that intersects with the range defined + // by charnum/nchars. + nscoord textLength = 0; + TextRenderedRunIterator runIter(this, TextRenderedRunIterator::eAllFrames); + TextRenderedRun run = runIter.Current(); + while (run.mFrame) { + // If this rendered run is past the substring we are interested in, we + // are done. + uint32_t offset = run.mTextElementCharIndex; + if (offset >= charnum + nchars) { + break; + } + + // Intersect the substring we are interested in with the range covered by + // the rendered run. + uint32_t length = run.mTextFrameContentLength; + IntersectInterval(offset, length, charnum, nchars); + + if (length != 0) { + // Convert offset into an index into the frame. + offset += run.mTextFrameContentOffset - run.mTextElementCharIndex; + + gfxSkipCharsIterator it = + run.mFrame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = run.mFrame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(run.mFrame, it); + + Range range = ConvertOriginalToSkipped(it, offset, length); + + // Accumulate the advance. + textLength += textRun->GetAdvanceWidth(range, &provider); + } + + run = runIter.Next(); + } + + nsPresContext* presContext = PresContext(); + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + + return presContext->AppUnitsToGfxUnits(textLength) * cssPxPerDevPx / + mFontSizeScaleFactor; +} + +/** + * Implements the SVG DOM GetCharNumAtPosition method for the specified + * text content element. + */ +int32_t SVGTextFrame::GetCharNumAtPosition(nsIContent* aContent, + const DOMPointInit& aPoint) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + return -1; + } + + UpdateGlyphPositioning(); + + nsPresContext* context = PresContext(); + + gfxPoint p(aPoint.mX, aPoint.mY); + + int32_t result = -1; + + TextRenderedRunIterator it(this, TextRenderedRunIterator::eAllFrames, + aContent); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + // Hit test this rendered run. Later runs will override earlier ones. + int32_t index = run.GetCharNumAtPosition(context, p); + if (index != -1) { + result = index + run.mTextElementCharIndex; + } + } + + if (result == -1) { + return result; + } + + return ConvertTextElementCharIndexToAddressableIndex(result, aContent); +} + +/** + * Implements the SVG DOM GetStartPositionOfChar method for the specified + * text content element. + */ +already_AddRefed<DOMSVGPoint> SVGTextFrame::GetStartPositionOfChar( + nsIContent* aContent, uint32_t aCharNum, ErrorResult& aRv) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + aRv.ThrowInvalidStateError("No layout information available for SVG text"); + return nullptr; + } + + UpdateGlyphPositioning(); + + CharIterator it(this, CharIterator::eAddressable, aContent); + if (!it.AdvanceToSubtree() || !it.Next(aCharNum)) { + aRv.ThrowIndexSizeError("Character index out of range"); + return nullptr; + } + + // We need to return the start position of the whole glyph. + uint32_t startIndex = it.GlyphStartTextElementCharIndex(); + + RefPtr<DOMSVGPoint> point = + new DOMSVGPoint(ToPoint(mPositions[startIndex].mPosition)); + return point.forget(); +} + +/** + * Returns the advance of the entire glyph whose starting character is at + * aTextElementCharIndex. + * + * aIterator, if provided, must be a CharIterator that already points to + * aTextElementCharIndex that is restricted to aContent and is using + * filter mode eAddressable. + */ +static gfxFloat GetGlyphAdvance(SVGTextFrame* aFrame, nsIContent* aContent, + uint32_t aTextElementCharIndex, + CharIterator* aIterator) { + MOZ_ASSERT(!aIterator || (aIterator->Filter() == CharIterator::eAddressable && + aIterator->GetSubtree() == aContent && + aIterator->GlyphStartTextElementCharIndex() == + aTextElementCharIndex), + "Invalid aIterator"); + + Maybe<CharIterator> newIterator; + CharIterator* it = aIterator; + if (!it) { + newIterator.emplace(aFrame, CharIterator::eAddressable, aContent); + if (!newIterator->AdvanceToSubtree()) { + MOZ_ASSERT_UNREACHABLE("Invalid aContent"); + return 0.0; + } + it = newIterator.ptr(); + } + + while (it->GlyphStartTextElementCharIndex() != aTextElementCharIndex) { + if (!it->Next()) { + MOZ_ASSERT_UNREACHABLE("Invalid aTextElementCharIndex"); + return 0.0; + } + } + + if (it->AtEnd()) { + MOZ_ASSERT_UNREACHABLE("Invalid aTextElementCharIndex"); + return 0.0; + } + + nsPresContext* presContext = aFrame->PresContext(); + gfxFloat advance = 0.0; + + for (;;) { + advance += it->GetAdvance(presContext); + if (!it->Next() || + it->GlyphStartTextElementCharIndex() != aTextElementCharIndex) { + break; + } + } + + return advance; +} + +/** + * Implements the SVG DOM GetEndPositionOfChar method for the specified + * text content element. + */ +already_AddRefed<DOMSVGPoint> SVGTextFrame::GetEndPositionOfChar( + nsIContent* aContent, uint32_t aCharNum, ErrorResult& aRv) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + aRv.ThrowInvalidStateError("No layout information available for SVG text"); + return nullptr; + } + + UpdateGlyphPositioning(); + + CharIterator it(this, CharIterator::eAddressable, aContent); + if (!it.AdvanceToSubtree() || !it.Next(aCharNum)) { + aRv.ThrowIndexSizeError("Character index out of range"); + return nullptr; + } + + // We need to return the end position of the whole glyph. + uint32_t startIndex = it.GlyphStartTextElementCharIndex(); + + // Get the advance of the glyph. + gfxFloat advance = + GetGlyphAdvance(this, aContent, startIndex, + it.IsClusterAndLigatureGroupStart() ? &it : nullptr); + if (it.TextRun()->IsRightToLeft()) { + advance = -advance; + } + + // The end position is the start position plus the advance in the direction + // of the glyph's rotation. + Matrix m = Matrix::Rotation(mPositions[startIndex].mAngle) * + Matrix::Translation(ToPoint(mPositions[startIndex].mPosition)); + Point p = m.TransformPoint(Point(advance / mFontSizeScaleFactor, 0)); + + RefPtr<DOMSVGPoint> point = new DOMSVGPoint(p); + return point.forget(); +} + +/** + * Implements the SVG DOM GetExtentOfChar method for the specified + * text content element. + */ +already_AddRefed<SVGRect> SVGTextFrame::GetExtentOfChar(nsIContent* aContent, + uint32_t aCharNum, + ErrorResult& aRv) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + aRv.ThrowInvalidStateError("No layout information available for SVG text"); + return nullptr; + } + + UpdateGlyphPositioning(); + + // Search for the character whose addressable index is aCharNum. + CharIterator it(this, CharIterator::eAddressable, aContent); + if (!it.AdvanceToSubtree() || !it.Next(aCharNum)) { + aRv.ThrowIndexSizeError("Character index out of range"); + return nullptr; + } + + nsPresContext* presContext = PresContext(); + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + + nsTextFrame* textFrame = it.TextFrame(); + uint32_t startIndex = it.GlyphStartTextElementCharIndex(); + bool isRTL = it.TextRun()->IsRightToLeft(); + bool isVertical = it.TextRun()->IsVertical(); + + // Get the glyph advance. + gfxFloat advance = + GetGlyphAdvance(this, aContent, startIndex, + it.IsClusterAndLigatureGroupStart() ? &it : nullptr); + gfxFloat x = isRTL ? -advance : 0.0; + + // The ascent and descent gives the height of the glyph. + gfxFloat ascent, descent; + GetAscentAndDescentInAppUnits(textFrame, ascent, descent); + + // The horizontal extent is the origin of the glyph plus the advance + // in the direction of the glyph's rotation. + gfxMatrix m; + m.PreTranslate(mPositions[startIndex].mPosition); + m.PreRotate(mPositions[startIndex].mAngle); + m.PreScale(1 / mFontSizeScaleFactor, 1 / mFontSizeScaleFactor); + + gfxRect glyphRect; + if (isVertical) { + glyphRect = gfxRect( + -presContext->AppUnitsToGfxUnits(descent) * cssPxPerDevPx, x, + presContext->AppUnitsToGfxUnits(ascent + descent) * cssPxPerDevPx, + advance); + } else { + glyphRect = gfxRect( + x, -presContext->AppUnitsToGfxUnits(ascent) * cssPxPerDevPx, advance, + presContext->AppUnitsToGfxUnits(ascent + descent) * cssPxPerDevPx); + } + + // Transform the glyph's rect into user space. + gfxRect r = m.TransformBounds(glyphRect); + + RefPtr<SVGRect> rect = new SVGRect(aContent, ToRect(r)); + return rect.forget(); +} + +/** + * Implements the SVG DOM GetRotationOfChar method for the specified + * text content element. + */ +float SVGTextFrame::GetRotationOfChar(nsIContent* aContent, uint32_t aCharNum, + ErrorResult& aRv) { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid->IsSubtreeDirty()) { + // We're never reflowed if we're under a non-SVG element that is + // never reflowed (such as the HTML 'caption' element). + aRv.ThrowInvalidStateError("No layout information available for SVG text"); + return 0; + } + + UpdateGlyphPositioning(); + + CharIterator it(this, CharIterator::eAddressable, aContent); + if (!it.AdvanceToSubtree() || !it.Next(aCharNum)) { + aRv.ThrowIndexSizeError("Character index out of range"); + return 0; + } + + // we need to account for the glyph's underlying orientation + const gfxTextRun::GlyphRun& glyphRun = it.GlyphRun(); + int32_t glyphOrientation = + 90 * (glyphRun.IsSidewaysRight() - glyphRun.IsSidewaysLeft()); + + return mPositions[it.TextElementCharIndex()].mAngle * 180.0 / M_PI + + glyphOrientation; +} + +//---------------------------------------------------------------------- +// SVGTextFrame text layout methods + +/** + * Given the character position array before values have been filled in + * to any unspecified positions, and an array of dx/dy values, returns whether + * a character at a given index should start a new rendered run. + * + * @param aPositions The array of character positions before unspecified + * positions have been filled in and dx/dy values have been added to them. + * @param aDeltas The array of dx/dy values. + * @param aIndex The character index in question. + */ +static bool ShouldStartRunAtIndex(const nsTArray<CharPosition>& aPositions, + const nsTArray<gfxPoint>& aDeltas, + uint32_t aIndex) { + if (aIndex == 0) { + return true; + } + + if (aIndex < aPositions.Length()) { + // If an explicit x or y value was given, start a new run. + if (aPositions[aIndex].IsXSpecified() || + aPositions[aIndex].IsYSpecified()) { + return true; + } + + // If a non-zero rotation was given, or the previous character had a non- + // zero rotation, start a new run. + if ((aPositions[aIndex].IsAngleSpecified() && + aPositions[aIndex].mAngle != 0.0f) || + (aPositions[aIndex - 1].IsAngleSpecified() && + (aPositions[aIndex - 1].mAngle != 0.0f))) { + return true; + } + } + + if (aIndex < aDeltas.Length()) { + // If a non-zero dx or dy value was given, start a new run. + if (aDeltas[aIndex].x != 0.0 || aDeltas[aIndex].y != 0.0) { + return true; + } + } + + return false; +} + +bool SVGTextFrame::ResolvePositionsForNode(nsIContent* aContent, + uint32_t& aIndex, bool aInTextPath, + bool& aForceStartOfChunk, + nsTArray<gfxPoint>& aDeltas) { + if (aContent->IsText()) { + // We found a text node. + uint32_t length = aContent->AsText()->TextLength(); + if (length) { + uint32_t end = aIndex + length; + if (MOZ_UNLIKELY(end > mPositions.Length())) { + MOZ_ASSERT_UNREACHABLE( + "length of mPositions does not match characters " + "found by iterating content"); + return false; + } + if (aForceStartOfChunk) { + // Note this character as starting a new anchored chunk. + mPositions[aIndex].mStartOfChunk = true; + aForceStartOfChunk = false; + } + while (aIndex < end) { + // Record whether each of these characters should start a new rendered + // run. That is always the case for characters on a text path. + // + // Run boundaries due to rotate="" values are handled in + // DoGlyphPositioning. + if (aInTextPath || ShouldStartRunAtIndex(mPositions, aDeltas, aIndex)) { + mPositions[aIndex].mRunBoundary = true; + } + aIndex++; + } + } + return true; + } + + // Skip past elements that aren't text content elements. + if (!IsTextContentElement(aContent)) { + return true; + } + + if (aContent->IsSVGElement(nsGkAtoms::textPath)) { + // Any ‘y’ attributes on horizontal <textPath> elements are ignored. + // Similarly, for vertical <texPath>s x attributes are ignored. + // <textPath> elements behave as if they have x="0" y="0" on them, but only + // if there is not a value for the non-ignored coordinate that got inherited + // from a parent. We skip this if there is no text content, so that empty + // <textPath>s don't interrupt the layout of text in the parent element. + if (HasTextContent(aContent)) { + if (MOZ_UNLIKELY(aIndex >= mPositions.Length())) { + MOZ_ASSERT_UNREACHABLE( + "length of mPositions does not match characters " + "found by iterating content"); + return false; + } + bool vertical = GetWritingMode().IsVertical(); + if (vertical || !mPositions[aIndex].IsXSpecified()) { + mPositions[aIndex].mPosition.x = 0.0; + } + if (!vertical || !mPositions[aIndex].IsYSpecified()) { + mPositions[aIndex].mPosition.y = 0.0; + } + mPositions[aIndex].mStartOfChunk = true; + } + } else if (!aContent->IsSVGElement(nsGkAtoms::a)) { + MOZ_ASSERT(aContent->IsSVGElement()); + + // We have a text content element that can have x/y/dx/dy/rotate attributes. + SVGElement* element = static_cast<SVGElement*>(aContent); + + // Get x, y, dx, dy. + SVGUserUnitList x, y, dx, dy; + element->GetAnimatedLengthListValues(&x, &y, &dx, &dy, nullptr); + + // Get rotate. + const SVGNumberList* rotate = nullptr; + SVGAnimatedNumberList* animatedRotate = + element->GetAnimatedNumberList(nsGkAtoms::rotate); + if (animatedRotate) { + rotate = &animatedRotate->GetAnimValue(); + } + + bool percentages = false; + uint32_t count = GetTextContentLength(aContent); + + if (MOZ_UNLIKELY(aIndex + count > mPositions.Length())) { + MOZ_ASSERT_UNREACHABLE( + "length of mPositions does not match characters " + "found by iterating content"); + return false; + } + + // New text anchoring chunks start at each character assigned a position + // with x="" or y="", or if we forced one with aForceStartOfChunk due to + // being just after a <textPath>. + uint32_t newChunkCount = std::max(x.Length(), y.Length()); + if (!newChunkCount && aForceStartOfChunk) { + newChunkCount = 1; + } + for (uint32_t i = 0, j = 0; i < newChunkCount && j < count; j++) { + if (!mPositions[aIndex + j].mUnaddressable) { + mPositions[aIndex + j].mStartOfChunk = true; + i++; + } + } + + // Copy dx="" and dy="" values into aDeltas. + if (!dx.IsEmpty() || !dy.IsEmpty()) { + // Any unspecified deltas when we grow the array just get left as 0s. + aDeltas.EnsureLengthAtLeast(aIndex + count); + for (uint32_t i = 0, j = 0; i < dx.Length() && j < count; j++) { + if (!mPositions[aIndex + j].mUnaddressable) { + aDeltas[aIndex + j].x = dx[i]; + percentages = percentages || dx.HasPercentageValueAt(i); + i++; + } + } + for (uint32_t i = 0, j = 0; i < dy.Length() && j < count; j++) { + if (!mPositions[aIndex + j].mUnaddressable) { + aDeltas[aIndex + j].y = dy[i]; + percentages = percentages || dy.HasPercentageValueAt(i); + i++; + } + } + } + + // Copy x="" and y="" values. + for (uint32_t i = 0, j = 0; i < x.Length() && j < count; j++) { + if (!mPositions[aIndex + j].mUnaddressable) { + mPositions[aIndex + j].mPosition.x = x[i]; + percentages = percentages || x.HasPercentageValueAt(i); + i++; + } + } + for (uint32_t i = 0, j = 0; i < y.Length() && j < count; j++) { + if (!mPositions[aIndex + j].mUnaddressable) { + mPositions[aIndex + j].mPosition.y = y[i]; + percentages = percentages || y.HasPercentageValueAt(i); + i++; + } + } + + // Copy rotate="" values. + if (rotate && !rotate->IsEmpty()) { + uint32_t i = 0, j = 0; + while (i < rotate->Length() && j < count) { + if (!mPositions[aIndex + j].mUnaddressable) { + mPositions[aIndex + j].mAngle = M_PI * (*rotate)[i] / 180.0; + i++; + } + j++; + } + // Propagate final rotate="" value to the end of this element. + while (j < count) { + mPositions[aIndex + j].mAngle = mPositions[aIndex + j - 1].mAngle; + j++; + } + } + + if (percentages) { + AddStateBits(NS_STATE_SVG_POSITIONING_MAY_USE_PERCENTAGES); + } + } + + // Recurse to children. + bool inTextPath = aInTextPath || aContent->IsSVGElement(nsGkAtoms::textPath); + for (nsIContent* child = aContent->GetFirstChild(); child; + child = child->GetNextSibling()) { + bool ok = ResolvePositionsForNode(child, aIndex, inTextPath, + aForceStartOfChunk, aDeltas); + if (!ok) { + return false; + } + } + + if (aContent->IsSVGElement(nsGkAtoms::textPath)) { + // Force a new anchored chunk just after a <textPath>. + aForceStartOfChunk = true; + } + + return true; +} + +bool SVGTextFrame::ResolvePositions(nsTArray<gfxPoint>& aDeltas, + bool aRunPerGlyph) { + NS_ASSERTION(mPositions.IsEmpty(), "expected mPositions to be empty"); + RemoveStateBits(NS_STATE_SVG_POSITIONING_MAY_USE_PERCENTAGES); + + CharIterator it(this, CharIterator::eOriginal, /* aSubtree */ nullptr); + if (it.AtEnd()) { + return false; + } + + // We assume the first character position is (0,0) unless we later see + // otherwise, and note it as unaddressable if it is. + bool firstCharUnaddressable = it.IsOriginalCharUnaddressable(); + mPositions.AppendElement(CharPosition::Unspecified(firstCharUnaddressable)); + + // Fill in unspecified positions for all remaining characters, noting + // them as unaddressable if they are. + uint32_t index = 0; + while (it.Next()) { + while (++index < it.TextElementCharIndex()) { + mPositions.AppendElement(CharPosition::Unspecified(false)); + } + mPositions.AppendElement( + CharPosition::Unspecified(it.IsOriginalCharUnaddressable())); + } + while (++index < it.TextElementCharIndex()) { + mPositions.AppendElement(CharPosition::Unspecified(false)); + } + + // Recurse over the content and fill in character positions as we go. + bool forceStartOfChunk = false; + index = 0; + bool ok = ResolvePositionsForNode(mContent, index, aRunPerGlyph, + forceStartOfChunk, aDeltas); + return ok && index > 0; +} + +void SVGTextFrame::DetermineCharPositions(nsTArray<nsPoint>& aPositions) { + NS_ASSERTION(aPositions.IsEmpty(), "expected aPositions to be empty"); + + nsPoint position; + + TextFrameIterator frit(this); + for (nsTextFrame* frame = frit.Current(); frame; frame = frit.Next()) { + gfxSkipCharsIterator it = frame->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = frame->GetTextRun(nsTextFrame::eInflated); + nsTextFrame::PropertyProvider provider(frame, it); + + // Reset the position to the new frame's position. + position = frit.Position(); + if (textRun->IsVertical()) { + if (textRun->IsRightToLeft()) { + position.y += frame->GetRect().height; + } + position.x += GetBaselinePosition(frame, textRun, frit.DominantBaseline(), + mFontSizeScaleFactor); + } else { + if (textRun->IsRightToLeft()) { + position.x += frame->GetRect().width; + } + position.y += GetBaselinePosition(frame, textRun, frit.DominantBaseline(), + mFontSizeScaleFactor); + } + + // Any characters not in a frame, e.g. when display:none. + for (uint32_t i = 0; i < frit.UndisplayedCharacters(); i++) { + aPositions.AppendElement(position); + } + + // Any white space characters trimmed at the start of the line of text. + nsTextFrame::TrimmedOffsets trimmedOffsets = + frame->GetTrimmedOffsets(frame->TextFragment()); + while (it.GetOriginalOffset() < trimmedOffsets.mStart) { + aPositions.AppendElement(position); + it.AdvanceOriginal(1); + } + + // Visible characters in the text frame. + while (it.GetOriginalOffset() < frame->GetContentEnd()) { + aPositions.AppendElement(position); + if (!it.IsOriginalCharSkipped()) { + // Accumulate partial ligature advance into position. (We must get + // partial advances rather than get the advance of the whole ligature + // group / cluster at once, since the group may span text frames, and + // the PropertyProvider only has spacing information for the current + // text frame.) + uint32_t offset = it.GetSkippedOffset(); + nscoord advance = + textRun->GetAdvanceWidth(Range(offset, offset + 1), &provider); + (textRun->IsVertical() ? position.y : position.x) += + textRun->IsRightToLeft() ? -advance : advance; + } + it.AdvanceOriginal(1); + } + } + + // Finally any characters at the end that are not in a frame. + for (uint32_t i = 0; i < frit.UndisplayedCharacters(); i++) { + aPositions.AppendElement(position); + } +} + +/** + * Physical text-anchor values. + */ +enum TextAnchorSide { eAnchorLeft, eAnchorMiddle, eAnchorRight }; + +/** + * Converts a logical text-anchor value to its physical value, based on whether + * it is for an RTL frame. + */ +static TextAnchorSide ConvertLogicalTextAnchorToPhysical( + StyleTextAnchor aTextAnchor, bool aIsRightToLeft) { + NS_ASSERTION(uint8_t(aTextAnchor) <= 3, "unexpected value for aTextAnchor"); + if (!aIsRightToLeft) { + return TextAnchorSide(uint8_t(aTextAnchor)); + } + return TextAnchorSide(2 - uint8_t(aTextAnchor)); +} + +/** + * Shifts the recorded character positions for an anchored chunk. + * + * @param aCharPositions The recorded character positions. + * @param aChunkStart The character index the starts the anchored chunk. This + * character's initial position is the anchor point. + * @param aChunkEnd The character index just after the end of the anchored + * chunk. + * @param aVisIStartEdge The left/top-most edge of any of the glyphs within the + * anchored chunk. + * @param aVisIEndEdge The right/bottom-most edge of any of the glyphs within + * the anchored chunk. + * @param aAnchorSide The direction to anchor. + */ +static void ShiftAnchoredChunk(nsTArray<CharPosition>& aCharPositions, + uint32_t aChunkStart, uint32_t aChunkEnd, + gfxFloat aVisIStartEdge, gfxFloat aVisIEndEdge, + TextAnchorSide aAnchorSide, bool aVertical) { + NS_ASSERTION(aVisIStartEdge <= aVisIEndEdge, + "unexpected anchored chunk edges"); + NS_ASSERTION(aChunkStart < aChunkEnd, + "unexpected values for aChunkStart and aChunkEnd"); + + gfxFloat shift = aVertical ? aCharPositions[aChunkStart].mPosition.y + : aCharPositions[aChunkStart].mPosition.x; + switch (aAnchorSide) { + case eAnchorLeft: + shift -= aVisIStartEdge; + break; + case eAnchorMiddle: + shift -= (aVisIStartEdge + aVisIEndEdge) / 2; + break; + case eAnchorRight: + shift -= aVisIEndEdge; + break; + default: + MOZ_ASSERT_UNREACHABLE("unexpected value for aAnchorSide"); + } + + if (shift != 0.0) { + if (aVertical) { + for (uint32_t i = aChunkStart; i < aChunkEnd; i++) { + aCharPositions[i].mPosition.y += shift; + } + } else { + for (uint32_t i = aChunkStart; i < aChunkEnd; i++) { + aCharPositions[i].mPosition.x += shift; + } + } + } +} + +void SVGTextFrame::AdjustChunksForLineBreaks() { + nsBlockFrame* block = do_QueryFrame(PrincipalChildList().FirstChild()); + NS_ASSERTION(block, "expected block frame"); + + nsBlockFrame::LineIterator line = block->LinesBegin(); + + CharIterator it(this, CharIterator::eOriginal, /* aSubtree */ nullptr); + while (!it.AtEnd() && line != block->LinesEnd()) { + if (it.TextFrame() == line->mFirstChild) { + mPositions[it.TextElementCharIndex()].mStartOfChunk = true; + line++; + } + it.AdvancePastCurrentFrame(); + } +} + +void SVGTextFrame::AdjustPositionsForClusters() { + nsPresContext* presContext = PresContext(); + + // Find all of the characters that are in the middle of a cluster or + // ligature group, and adjust their positions and rotations to match + // the first character of the cluster/group. + // + // Also move the boundaries of text rendered runs and anchored chunks to + // not lie in the middle of cluster/group. + + // The partial advance of the current cluster or ligature group that we + // have accumulated. + gfxFloat partialAdvance = 0.0; + + CharIterator it(this, CharIterator::eUnskipped, /* aSubtree */ nullptr); + while (!it.AtEnd()) { + if (it.IsClusterAndLigatureGroupStart()) { + // If we're at the start of a new cluster or ligature group, reset our + // accumulated partial advance. + partialAdvance = 0.0; + } else { + // Otherwise, we're in the middle of a cluster or ligature group, and + // we need to use the currently accumulated partial advance to adjust + // the character's position and rotation. + + // Find the start of the cluster/ligature group. + uint32_t charIndex = it.TextElementCharIndex(); + uint32_t startIndex = it.GlyphStartTextElementCharIndex(); + MOZ_ASSERT(charIndex != startIndex, + "If the current character is in the middle of a cluster or " + "ligature group, then charIndex must be different from " + "startIndex"); + + mPositions[charIndex].mClusterOrLigatureGroupMiddle = true; + + // Don't allow different rotations on ligature parts. + bool rotationAdjusted = false; + double angle = mPositions[startIndex].mAngle; + if (mPositions[charIndex].mAngle != angle) { + mPositions[charIndex].mAngle = angle; + rotationAdjusted = true; + } + + // Update the character position. + gfxFloat advance = partialAdvance / mFontSizeScaleFactor; + gfxPoint direction = gfxPoint(cos(angle), sin(angle)) * + (it.TextRun()->IsRightToLeft() ? -1.0 : 1.0); + if (it.TextRun()->IsVertical()) { + std::swap(direction.x, direction.y); + } + mPositions[charIndex].mPosition = + mPositions[startIndex].mPosition + direction * advance; + + // Ensure any runs that would end in the middle of a ligature now end just + // after the ligature. + if (mPositions[charIndex].mRunBoundary) { + mPositions[charIndex].mRunBoundary = false; + if (charIndex + 1 < mPositions.Length()) { + mPositions[charIndex + 1].mRunBoundary = true; + } + } else if (rotationAdjusted) { + if (charIndex + 1 < mPositions.Length()) { + mPositions[charIndex + 1].mRunBoundary = true; + } + } + + // Ensure any anchored chunks that would begin in the middle of a ligature + // now begin just after the ligature. + if (mPositions[charIndex].mStartOfChunk) { + mPositions[charIndex].mStartOfChunk = false; + if (charIndex + 1 < mPositions.Length()) { + mPositions[charIndex + 1].mStartOfChunk = true; + } + } + } + + // Accumulate the current character's partial advance. + partialAdvance += it.GetAdvance(presContext); + + it.Next(); + } +} + +already_AddRefed<Path> SVGTextFrame::GetTextPath(nsIFrame* aTextPathFrame) { + nsIContent* content = aTextPathFrame->GetContent(); + SVGTextPathElement* tp = static_cast<SVGTextPathElement*>(content); + if (tp->mPath.IsRendered()) { + // This is just an attribute so there's no transform that can apply + // so we can just return the path directly. + return tp->mPath.GetAnimValue().BuildPathForMeasuring(); + } + + SVGGeometryElement* geomElement = + SVGObserverUtils::GetAndObserveTextPathsPath(aTextPathFrame); + if (!geomElement) { + return nullptr; + } + + RefPtr<Path> path = geomElement->GetOrBuildPathForMeasuring(); + if (!path) { + return nullptr; + } + + gfxMatrix matrix = geomElement->PrependLocalTransformsTo(gfxMatrix()); + if (!matrix.IsIdentity()) { + // Apply the geometry element's transform + RefPtr<PathBuilder> builder = + path->TransformedCopyToBuilder(ToMatrix(matrix)); + path = builder->Finish(); + } + + return path.forget(); +} + +gfxFloat SVGTextFrame::GetOffsetScale(nsIFrame* aTextPathFrame) { + nsIContent* content = aTextPathFrame->GetContent(); + SVGTextPathElement* tp = static_cast<SVGTextPathElement*>(content); + if (tp->mPath.IsRendered()) { + // A path attribute has no pathLength or transform + // so we return a unit scale. + return 1.0; + } + + SVGGeometryElement* geomElement = + SVGObserverUtils::GetAndObserveTextPathsPath(aTextPathFrame); + if (!geomElement) { + return 1.0; + } + return geomElement->GetPathLengthScale(SVGGeometryElement::eForTextPath); +} + +gfxFloat SVGTextFrame::GetStartOffset(nsIFrame* aTextPathFrame) { + SVGTextPathElement* tp = + static_cast<SVGTextPathElement*>(aTextPathFrame->GetContent()); + SVGAnimatedLength* length = + &tp->mLengthAttributes[SVGTextPathElement::STARTOFFSET]; + + if (length->IsPercentage()) { + if (!std::isfinite(GetOffsetScale(aTextPathFrame))) { + // Either pathLength="0" for this path or the path has 0 length. + return 0.0; + } + RefPtr<Path> data = GetTextPath(aTextPathFrame); + return data ? length->GetAnimValInSpecifiedUnits() * data->ComputeLength() / + 100.0 + : 0.0; + } + float lengthValue = length->GetAnimValue(tp); + // If offsetScale is infinity we want to return 0 not NaN + return lengthValue == 0 ? 0.0 : lengthValue * GetOffsetScale(aTextPathFrame); +} + +void SVGTextFrame::DoTextPathLayout() { + nsPresContext* context = PresContext(); + + CharIterator it(this, CharIterator::eOriginal, /* aSubtree */ nullptr); + while (!it.AtEnd()) { + nsIFrame* textPathFrame = it.TextPathFrame(); + if (!textPathFrame) { + // Skip past this frame if we're not in a text path. + it.AdvancePastCurrentFrame(); + continue; + } + + // Get the path itself. + RefPtr<Path> path = GetTextPath(textPathFrame); + if (!path) { + uint32_t start = it.TextElementCharIndex(); + it.AdvancePastCurrentTextPathFrame(); + uint32_t end = it.TextElementCharIndex(); + for (uint32_t i = start; i < end; i++) { + mPositions[i].mHidden = true; + } + continue; + } + + SVGTextPathElement* textPath = + static_cast<SVGTextPathElement*>(textPathFrame->GetContent()); + uint16_t side = + textPath->EnumAttributes()[SVGTextPathElement::SIDE].GetAnimValue(); + + gfxFloat offset = GetStartOffset(textPathFrame); + Float pathLength = path->ComputeLength(); + + // If the first character within the text path is in the middle of a + // cluster or ligature group, just skip it and don't apply text path + // positioning. + while (!it.AtEnd()) { + if (it.IsOriginalCharSkipped()) { + it.Next(); + continue; + } + if (it.IsClusterAndLigatureGroupStart()) { + break; + } + it.Next(); + } + + bool skippedEndOfTextPath = false; + + // Loop for each character in the text path. + while (!it.AtEnd() && it.TextPathFrame() && + it.TextPathFrame()->GetContent() == textPath) { + // The index of the cluster or ligature group's first character. + uint32_t i = it.TextElementCharIndex(); + + // The index of the next character of the cluster or ligature. + // We track this as we loop over the characters below so that we + // can detect undisplayed characters and append entries into + // partialAdvances for them. + uint32_t j = i + 1; + + MOZ_ASSERT(!mPositions[i].mClusterOrLigatureGroupMiddle); + + gfxFloat sign = it.TextRun()->IsRightToLeft() ? -1.0 : 1.0; + bool vertical = it.TextRun()->IsVertical(); + + // Compute cumulative advances for each character of the cluster or + // ligature group. + AutoTArray<gfxFloat, 4> partialAdvances; + gfxFloat partialAdvance = it.GetAdvance(context); + partialAdvances.AppendElement(partialAdvance); + while (it.Next()) { + // Append entries for any undisplayed characters the CharIterator + // skipped over. + MOZ_ASSERT(j <= it.TextElementCharIndex()); + while (j < it.TextElementCharIndex()) { + partialAdvances.AppendElement(partialAdvance); + ++j; + } + // This loop may end up outside of the current text path, but + // that's OK; we'll consider any complete cluster or ligature + // group that begins inside the text path as being affected + // by it. + if (it.IsOriginalCharSkipped()) { + if (!it.TextPathFrame()) { + skippedEndOfTextPath = true; + break; + } + // Leave partialAdvance unchanged. + } else if (it.IsClusterAndLigatureGroupStart()) { + break; + } else { + partialAdvance += it.GetAdvance(context); + } + partialAdvances.AppendElement(partialAdvance); + } + + if (!skippedEndOfTextPath) { + // Any final undisplayed characters the CharIterator skipped over. + MOZ_ASSERT(j <= it.TextElementCharIndex()); + while (j < it.TextElementCharIndex()) { + partialAdvances.AppendElement(partialAdvance); + ++j; + } + } + + gfxFloat halfAdvance = + partialAdvances.LastElement() / mFontSizeScaleFactor / 2.0; + gfxFloat midx = + (vertical ? mPositions[i].mPosition.y : mPositions[i].mPosition.x) + + sign * halfAdvance + offset; + + // Hide the character if it falls off the end of the path. + mPositions[i].mHidden = midx < 0 || midx > pathLength; + + // Position the character on the path at the right angle. + Point tangent; // Unit vector tangent to the point we find. + Point pt; + if (side == TEXTPATH_SIDETYPE_RIGHT) { + pt = path->ComputePointAtLength(Float(pathLength - midx), &tangent); + tangent = -tangent; + } else { + pt = path->ComputePointAtLength(Float(midx), &tangent); + } + Float rotation = vertical ? atan2f(-tangent.x, tangent.y) + : atan2f(tangent.y, tangent.x); + Point normal(-tangent.y, tangent.x); // Unit vector normal to the point. + Point offsetFromPath = normal * (vertical ? -mPositions[i].mPosition.x + : mPositions[i].mPosition.y); + pt += offsetFromPath; + Point direction = tangent * sign; + mPositions[i].mPosition = + ThebesPoint(pt) - ThebesPoint(direction) * halfAdvance; + mPositions[i].mAngle += rotation; + + // Position any characters for a partial ligature. + for (uint32_t k = i + 1; k < j; k++) { + gfxPoint partialAdvance = ThebesPoint(direction) * + partialAdvances[k - i] / mFontSizeScaleFactor; + mPositions[k].mPosition = mPositions[i].mPosition + partialAdvance; + mPositions[k].mAngle = mPositions[i].mAngle; + mPositions[k].mHidden = mPositions[i].mHidden; + } + } + } +} + +void SVGTextFrame::DoAnchoring() { + nsPresContext* presContext = PresContext(); + + CharIterator it(this, CharIterator::eOriginal, /* aSubtree */ nullptr); + + // Don't need to worry about skipped or trimmed characters. + while (!it.AtEnd() && + (it.IsOriginalCharSkipped() || it.IsOriginalCharTrimmed())) { + it.Next(); + } + + bool vertical = GetWritingMode().IsVertical(); + uint32_t start = it.TextElementCharIndex(); + while (start < mPositions.Length()) { + it.AdvanceToCharacter(start); + nsTextFrame* chunkFrame = it.TextFrame(); + + // Measure characters in this chunk to find the left-most and right-most + // edges of all glyphs within the chunk. + uint32_t index = it.TextElementCharIndex(); + uint32_t end = start; + gfxFloat left = std::numeric_limits<gfxFloat>::infinity(); + gfxFloat right = -std::numeric_limits<gfxFloat>::infinity(); + do { + if (!it.IsOriginalCharSkipped() && !it.IsOriginalCharTrimmed()) { + gfxFloat advance = it.GetAdvance(presContext) / mFontSizeScaleFactor; + gfxFloat pos = it.TextRun()->IsVertical() + ? mPositions[index].mPosition.y + : mPositions[index].mPosition.x; + if (it.TextRun()->IsRightToLeft()) { + left = std::min(left, pos - advance); + right = std::max(right, pos); + } else { + left = std::min(left, pos); + right = std::max(right, pos + advance); + } + } + it.Next(); + index = end = it.TextElementCharIndex(); + } while (!it.AtEnd() && !mPositions[end].mStartOfChunk); + + if (left != std::numeric_limits<gfxFloat>::infinity()) { + bool isRTL = + chunkFrame->StyleVisibility()->mDirection == StyleDirection::Rtl; + TextAnchorSide anchor = ConvertLogicalTextAnchorToPhysical( + chunkFrame->StyleSVG()->mTextAnchor, isRTL); + + ShiftAnchoredChunk(mPositions, start, end, left, right, anchor, vertical); + } + + start = it.TextElementCharIndex(); + } +} + +void SVGTextFrame::DoGlyphPositioning() { + mPositions.Clear(); + RemoveStateBits(NS_STATE_SVG_POSITIONING_DIRTY); + + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (kid && kid->IsSubtreeDirty()) { + MOZ_ASSERT(false, "should have already reflowed the kid"); + return; + } + + // Since we can be called directly via GetBBoxContribution, our correspondence + // may not be up to date. + TextNodeCorrespondenceRecorder::RecordCorrespondence(this); + + // Determine the positions of each character in app units. + AutoTArray<nsPoint, 64> charPositions; + DetermineCharPositions(charPositions); + + if (charPositions.IsEmpty()) { + // No characters, so nothing to do. + return; + } + + // If the textLength="" attribute was specified, then we need ResolvePositions + // to record that a new run starts with each glyph. + SVGTextContentElement* element = + static_cast<SVGTextContentElement*>(GetContent()); + SVGAnimatedLength* textLengthAttr = + element->GetAnimatedLength(nsGkAtoms::textLength); + uint16_t lengthAdjust = + element->EnumAttributes()[SVGTextContentElement::LENGTHADJUST] + .GetAnimValue(); + bool adjustingTextLength = textLengthAttr->IsExplicitlySet(); + float expectedTextLength = textLengthAttr->GetAnimValue(element); + + if (adjustingTextLength && + (expectedTextLength < 0.0f || lengthAdjust == LENGTHADJUST_UNKNOWN)) { + // If textLength="" is less than zero or lengthAdjust is unknown, ignore it. + adjustingTextLength = false; + } + + // Get the x, y, dx, dy, rotate values for the subtree. + AutoTArray<gfxPoint, 16> deltas; + if (!ResolvePositions(deltas, adjustingTextLength)) { + // If ResolvePositions returned false, it means either there were some + // characters in the DOM but none of them are displayed, or there was + // an error in processing mPositions. Clear out mPositions so that we don't + // attempt to do any painting later. + mPositions.Clear(); + return; + } + + // XXX We might be able to do less work when there is at most a single + // x/y/dx/dy position. + + // Truncate the positioning arrays to the actual number of characters present. + TruncateTo(deltas, charPositions); + TruncateTo(mPositions, charPositions); + + // Fill in an unspecified character position at index 0. + if (!mPositions[0].IsXSpecified()) { + mPositions[0].mPosition.x = 0.0; + } + if (!mPositions[0].IsYSpecified()) { + mPositions[0].mPosition.y = 0.0; + } + if (!mPositions[0].IsAngleSpecified()) { + mPositions[0].mAngle = 0.0; + } + + nsPresContext* presContext = PresContext(); + bool vertical = GetWritingMode().IsVertical(); + + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + double factor = cssPxPerDevPx / mFontSizeScaleFactor; + + // Determine how much to compress or expand glyph positions due to + // textLength="" and lengthAdjust="". + double adjustment = 0.0; + mLengthAdjustScaleFactor = 1.0f; + if (adjustingTextLength) { + nscoord frameLength = + vertical ? PrincipalChildList().FirstChild()->GetRect().height + : PrincipalChildList().FirstChild()->GetRect().width; + float actualTextLength = static_cast<float>( + presContext->AppUnitsToGfxUnits(frameLength) * factor); + + switch (lengthAdjust) { + case LENGTHADJUST_SPACINGANDGLYPHS: + // Scale the glyphs and their positions. + if (actualTextLength > 0) { + mLengthAdjustScaleFactor = expectedTextLength / actualTextLength; + } + break; + + default: + MOZ_ASSERT(lengthAdjust == LENGTHADJUST_SPACING); + // Just add space between each glyph. + int32_t adjustableSpaces = 0; + for (uint32_t i = 1; i < mPositions.Length(); i++) { + if (!mPositions[i].mUnaddressable) { + adjustableSpaces++; + } + } + if (adjustableSpaces) { + adjustment = + (expectedTextLength - actualTextLength) / adjustableSpaces; + } + break; + } + } + + // Fill in any unspecified character positions based on the positions recorded + // in charPositions, and also add in the dx/dy values. + if (!deltas.IsEmpty()) { + mPositions[0].mPosition += deltas[0]; + } + + gfxFloat xLengthAdjustFactor = vertical ? 1.0 : mLengthAdjustScaleFactor; + gfxFloat yLengthAdjustFactor = vertical ? mLengthAdjustScaleFactor : 1.0; + for (uint32_t i = 1; i < mPositions.Length(); i++) { + // Fill in unspecified x position. + if (!mPositions[i].IsXSpecified()) { + nscoord d = charPositions[i].x - charPositions[i - 1].x; + mPositions[i].mPosition.x = + mPositions[i - 1].mPosition.x + + presContext->AppUnitsToGfxUnits(d) * factor * xLengthAdjustFactor; + if (!vertical && !mPositions[i].mUnaddressable) { + mPositions[i].mPosition.x += adjustment; + } + } + // Fill in unspecified y position. + if (!mPositions[i].IsYSpecified()) { + nscoord d = charPositions[i].y - charPositions[i - 1].y; + mPositions[i].mPosition.y = + mPositions[i - 1].mPosition.y + + presContext->AppUnitsToGfxUnits(d) * factor * yLengthAdjustFactor; + if (vertical && !mPositions[i].mUnaddressable) { + mPositions[i].mPosition.y += adjustment; + } + } + // Add in dx/dy. + if (i < deltas.Length()) { + mPositions[i].mPosition += deltas[i]; + } + // Fill in unspecified rotation values. + if (!mPositions[i].IsAngleSpecified()) { + mPositions[i].mAngle = 0.0f; + } + } + + MOZ_ASSERT(mPositions.Length() == charPositions.Length()); + + AdjustChunksForLineBreaks(); + AdjustPositionsForClusters(); + DoAnchoring(); + DoTextPathLayout(); +} + +bool SVGTextFrame::ShouldRenderAsPath(nsTextFrame* aFrame, + bool& aShouldPaintSVGGlyphs) { + // Rendering to a clip path. + if (HasAnyStateBits(NS_STATE_SVG_CLIPPATH_CHILD)) { + aShouldPaintSVGGlyphs = false; + return true; + } + + aShouldPaintSVGGlyphs = true; + + const nsStyleSVG* style = aFrame->StyleSVG(); + + // Fill is a non-solid paint, has a non-default fill-rule or has + // non-1 opacity. + if (!(style->mFill.kind.IsNone() || + (style->mFill.kind.IsColor() && style->mFillOpacity.IsOpacity() && + style->mFillOpacity.AsOpacity() == 1))) { + return true; + } + + // Text has a stroke. + if (style->HasStroke()) { + if (style->mStrokeWidth.IsContextValue()) { + return true; + } + if (SVGContentUtils::CoordToFloat( + static_cast<SVGElement*>(GetContent()), + style->mStrokeWidth.AsLengthPercentage()) > 0) { + return true; + } + } + + return false; +} + +void SVGTextFrame::ScheduleReflowSVG() { + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + ScheduleReflowSVGNonDisplayText( + IntrinsicDirty::FrameAncestorsAndDescendants); + } else { + SVGUtils::ScheduleReflowSVG(this); + } +} + +void SVGTextFrame::NotifyGlyphMetricsChange(bool aUpdateTextCorrespondence) { + if (aUpdateTextCorrespondence) { + AddStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY); + } + AddStateBits(NS_STATE_SVG_POSITIONING_DIRTY); + nsLayoutUtils::PostRestyleEvent(mContent->AsElement(), RestyleHint{0}, + nsChangeHint_InvalidateRenderingObservers); + ScheduleReflowSVG(); +} + +void SVGTextFrame::UpdateGlyphPositioning() { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (!kid) { + return; + } + + if (HasAnyStateBits(NS_STATE_SVG_POSITIONING_DIRTY)) { + DoGlyphPositioning(); + } +} + +void SVGTextFrame::MaybeResolveBidiForAnonymousBlockChild() { + nsIFrame* kid = PrincipalChildList().FirstChild(); + + if (kid && kid->HasAnyStateBits(NS_BLOCK_NEEDS_BIDI_RESOLUTION) && + PresContext()->BidiEnabled()) { + MOZ_ASSERT(static_cast<nsBlockFrame*>(do_QueryFrame(kid)), + "Expect anonymous child to be an nsBlockFrame"); + nsBidiPresUtils::Resolve(static_cast<nsBlockFrame*>(kid)); + } +} + +void SVGTextFrame::MaybeReflowAnonymousBlockChild() { + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (!kid) { + return; + } + + NS_ASSERTION(!kid->HasAnyStateBits(NS_FRAME_IN_REFLOW), + "should not be in reflow when about to reflow again"); + + if (IsSubtreeDirty()) { + if (HasAnyStateBits(NS_FRAME_IS_DIRTY)) { + // If we require a full reflow, ensure our kid is marked fully dirty. + // (Note that our anonymous nsBlockFrame is not an ISVGDisplayableFrame, + // so even when we are called via our ReflowSVG this will not be done for + // us by SVGDisplayContainerFrame::ReflowSVG.) + kid->MarkSubtreeDirty(); + } + + // The RecordCorrespondence and DoReflow calls can result in new text frames + // being created (due to bidi resolution or reflow). We set this bit to + // guard against unnecessarily calling back in to + // ScheduleReflowSVGNonDisplayText from nsIFrame::DidSetComputedStyle on + // those new text frames. + AddStateBits(NS_STATE_SVG_TEXT_IN_REFLOW); + + TextNodeCorrespondenceRecorder::RecordCorrespondence(this); + + MOZ_ASSERT(SVGUtils::AnyOuterSVGIsCallingReflowSVG(this), + "should be under ReflowSVG"); + nsPresContext::InterruptPreventer noInterrupts(PresContext()); + DoReflow(); + + RemoveStateBits(NS_STATE_SVG_TEXT_IN_REFLOW); + } +} + +void SVGTextFrame::DoReflow() { + MOZ_ASSERT(HasAnyStateBits(NS_STATE_SVG_TEXT_IN_REFLOW)); + + // Since we are going to reflow the anonymous block frame, we will + // need to update mPositions. + // We also mark our text correspondence as dirty since we can end up needing + // reflow in ways that do not set NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY. + // (We'd then fail the "expected a TextNodeCorrespondenceProperty" assertion + // when UpdateGlyphPositioning() is called after we return.) + AddStateBits(NS_STATE_SVG_TEXT_CORRESPONDENCE_DIRTY | + NS_STATE_SVG_POSITIONING_DIRTY); + + if (HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + // Normally, these dirty flags would be cleared in ReflowSVG(), but that + // doesn't get called for non-display frames. We don't want to reflow our + // descendants every time SVGTextFrame::PaintSVG makes sure that we have + // valid positions by calling UpdateGlyphPositioning(), so we need to clear + // these dirty bits. Note that this also breaks an invalidation loop where + // our descendants invalidate as they reflow, which invalidates rendering + // observers, which reschedules the frame that is currently painting by + // referencing us to paint again. See bug 839958 comment 7. Hopefully we + // will break that loop more convincingly at some point. + RemoveStateBits(NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN); + } + + nsPresContext* presContext = PresContext(); + nsIFrame* kid = PrincipalChildList().FirstChild(); + if (!kid) { + return; + } + + UniquePtr<gfxContext> renderingContext = + presContext->PresShell()->CreateReferenceRenderingContext(); + + if (UpdateFontSizeScaleFactor()) { + // If the font size scale factor changed, we need the block to report + // an updated preferred width. + kid->MarkIntrinsicISizesDirty(); + } + + nscoord inlineSize = kid->GetPrefISize(renderingContext.get()); + WritingMode wm = kid->GetWritingMode(); + ReflowInput reflowInput(presContext, kid, renderingContext.get(), + LogicalSize(wm, inlineSize, NS_UNCONSTRAINEDSIZE)); + ReflowOutput desiredSize(reflowInput); + nsReflowStatus status; + + NS_ASSERTION( + reflowInput.ComputedPhysicalBorderPadding() == nsMargin(0, 0, 0, 0) && + reflowInput.ComputedPhysicalMargin() == nsMargin(0, 0, 0, 0), + "style system should ensure that :-moz-svg-text " + "does not get styled"); + + kid->Reflow(presContext, desiredSize, reflowInput, status); + kid->DidReflow(presContext, &reflowInput); + kid->SetSize(wm, desiredSize.Size(wm)); +} + +// Usable font size range in devpixels / user-units +#define CLAMP_MIN_SIZE 8.0 +#define CLAMP_MAX_SIZE 200.0 +#define PRECISE_SIZE 200.0 + +bool SVGTextFrame::UpdateFontSizeScaleFactor() { + double oldFontSizeScaleFactor = mFontSizeScaleFactor; + + nsPresContext* presContext = PresContext(); + + bool geometricPrecision = false; + CSSCoord min = std::numeric_limits<float>::max(); + CSSCoord max = std::numeric_limits<float>::min(); + bool anyText = false; + + // Find the minimum and maximum font sizes used over all the + // nsTextFrames. + TextFrameIterator it(this); + nsTextFrame* f = it.Current(); + while (f) { + if (!geometricPrecision) { + // Unfortunately we can't treat text-rendering:geometricPrecision + // separately for each text frame. + geometricPrecision = f->StyleText()->mTextRendering == + StyleTextRendering::Geometricprecision; + } + const auto& fontSize = f->StyleFont()->mFont.size; + if (!fontSize.IsZero()) { + min = std::min(min, fontSize.ToCSSPixels()); + max = std::max(max, fontSize.ToCSSPixels()); + anyText = true; + } + f = it.Next(); + } + + if (!anyText) { + // No text, so no need for scaling. + mFontSizeScaleFactor = 1.0; + return mFontSizeScaleFactor != oldFontSizeScaleFactor; + } + + if (geometricPrecision) { + // We want to ensure minSize is scaled to PRECISE_SIZE. + mFontSizeScaleFactor = PRECISE_SIZE / min; + return mFontSizeScaleFactor != oldFontSizeScaleFactor; + } + + // When we are non-display, we could be painted in different coordinate + // spaces, and we don't want to have to reflow for each of these. We + // just assume that the context scale is 1.0 for them all, so we don't + // get stuck with a font size scale factor based on whichever referencing + // frame happens to reflow first. + double contextScale = 1.0; + if (!HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) { + gfxMatrix m(GetCanvasTM()); + if (!m.IsSingular()) { + contextScale = GetContextScale(m); + if (!std::isfinite(contextScale)) { + contextScale = 1.0f; + } + } + } + mLastContextScale = contextScale; + + // But we want to ignore any scaling required due to HiDPI displays, since + // regular CSS text frames will still create text runs using the font size + // in CSS pixels, and we want SVG text to have the same rendering as HTML + // text for regular font sizes. + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + contextScale *= cssPxPerDevPx; + + double minTextRunSize = min * contextScale; + double maxTextRunSize = max * contextScale; + + if (minTextRunSize >= CLAMP_MIN_SIZE && maxTextRunSize <= CLAMP_MAX_SIZE) { + // We are already in the ideal font size range for all text frames, + // so we only have to take into account the contextScale. + mFontSizeScaleFactor = contextScale; + } else if (max / min > CLAMP_MAX_SIZE / CLAMP_MIN_SIZE) { + // We can't scale the font sizes so that all of the text frames lie + // within our ideal font size range. + // Heuristically, if the maxTextRunSize is within the CLAMP_MAX_SIZE + // as a reasonable value, it's likely to be the user's intent to + // get a valid font for the maxTextRunSize one, we should honor it. + // The same for minTextRunSize. + if (maxTextRunSize <= CLAMP_MAX_SIZE) { + mFontSizeScaleFactor = CLAMP_MAX_SIZE / max; + } else if (minTextRunSize >= CLAMP_MIN_SIZE) { + mFontSizeScaleFactor = CLAMP_MIN_SIZE / min; + } else { + // So maxTextRunSize is too big, minTextRunSize is too small, + // we can't really do anything for this case, just leave it as is. + mFontSizeScaleFactor = contextScale; + } + } else if (minTextRunSize < CLAMP_MIN_SIZE) { + mFontSizeScaleFactor = CLAMP_MIN_SIZE / min; + } else { + mFontSizeScaleFactor = CLAMP_MAX_SIZE / max; + } + + return mFontSizeScaleFactor != oldFontSizeScaleFactor; +} + +double SVGTextFrame::GetFontSizeScaleFactor() const { + return mFontSizeScaleFactor; +} + +/** + * Take aPoint, which is in the <text> element's user space, and convert + * it to the appropriate frame user space of aChildFrame according to + * which rendered run the point hits. + */ +Point SVGTextFrame::TransformFramePointToTextChild( + const Point& aPoint, const nsIFrame* aChildFrame) { + NS_ASSERTION(aChildFrame && nsLayoutUtils::GetClosestFrameOfType( + aChildFrame->GetParent(), + LayoutFrameType::SVGText) == this, + "aChildFrame must be a descendant of this frame"); + + UpdateGlyphPositioning(); + + nsPresContext* presContext = PresContext(); + + // Add in the mRect offset to aPoint, as that will have been taken into + // account when transforming the point from the ancestor frame down + // to this one. + float cssPxPerDevPx = nsPresContext::AppUnitsToFloatCSSPixels( + presContext->AppUnitsPerDevPixel()); + float factor = AppUnitsPerCSSPixel(); + Point framePosition(NSAppUnitsToFloatPixels(mRect.x, factor), + NSAppUnitsToFloatPixels(mRect.y, factor)); + Point pointInUserSpace = aPoint * cssPxPerDevPx + framePosition; + + // Find the closest rendered run for the text frames beneath aChildFrame. + TextRenderedRunIterator it(this, TextRenderedRunIterator::eAllFrames, + aChildFrame); + TextRenderedRun hit; + gfxPoint pointInRun; + nscoord dx = nscoord_MAX; + nscoord dy = nscoord_MAX; + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + uint32_t flags = TextRenderedRun::eIncludeFill | + TextRenderedRun::eIncludeStroke | + TextRenderedRun::eNoHorizontalOverflow; + gfxRect runRect = + run.GetRunUserSpaceRect(presContext, flags).ToThebesRect(); + + gfxMatrix m = run.GetTransformFromRunUserSpaceToUserSpace(presContext); + if (!m.Invert()) { + return aPoint; + } + gfxPoint pointInRunUserSpace = + m.TransformPoint(ThebesPoint(pointInUserSpace)); + + if (Inside(runRect, pointInRunUserSpace)) { + // The point was inside the rendered run's rect, so we choose it. + dx = 0; + dy = 0; + pointInRun = pointInRunUserSpace; + hit = run; + } else if (nsLayoutUtils::PointIsCloserToRect(pointInRunUserSpace, runRect, + dx, dy)) { + // The point was closer to this rendered run's rect than any others + // we've seen so far. + pointInRun.x = + clamped(pointInRunUserSpace.x.value, runRect.X(), runRect.XMost()); + pointInRun.y = + clamped(pointInRunUserSpace.y.value, runRect.Y(), runRect.YMost()); + hit = run; + } + } + + if (!hit.mFrame) { + // We didn't find any rendered runs for the frame. + return aPoint; + } + + // Return the point in user units relative to the nsTextFrame, + // but taking into account mFontSizeScaleFactor. + gfxMatrix m = hit.GetTransformFromRunUserSpaceToFrameUserSpace(presContext); + m.PreScale(mFontSizeScaleFactor, mFontSizeScaleFactor); + return ToPoint(m.TransformPoint(pointInRun) / cssPxPerDevPx); +} + +/** + * For each rendered run beneath aChildFrame, translate aRect from + * aChildFrame to the run's text frame, transform it then into + * the run's frame user space, intersect it with the run's + * frame user space rect, then transform it up to user space. + * The result is the union of all of these. + */ +gfxRect SVGTextFrame::TransformFrameRectFromTextChild( + const nsRect& aRect, const nsIFrame* aChildFrame) { + NS_ASSERTION(aChildFrame && nsLayoutUtils::GetClosestFrameOfType( + aChildFrame->GetParent(), + LayoutFrameType::SVGText) == this, + "aChildFrame must be a descendant of this frame"); + + UpdateGlyphPositioning(); + + nsPresContext* presContext = PresContext(); + + gfxRect result; + TextRenderedRunIterator it(this, TextRenderedRunIterator::eAllFrames, + aChildFrame); + for (TextRenderedRun run = it.Current(); run.mFrame; run = it.Next()) { + // First, translate aRect from aChildFrame to this run's frame. + nsRect rectInTextFrame = aRect + aChildFrame->GetOffsetTo(run.mFrame); + + // Scale it into frame user space. + gfxRect rectInFrameUserSpace = AppUnitsToFloatCSSPixels( + gfxRect(rectInTextFrame.x, rectInTextFrame.y, rectInTextFrame.width, + rectInTextFrame.height), + presContext); + + // Intersect it with the run. + uint32_t flags = + TextRenderedRun::eIncludeFill | TextRenderedRun::eIncludeStroke; + + if (rectInFrameUserSpace.IntersectRect( + rectInFrameUserSpace, + run.GetFrameUserSpaceRect(presContext, flags).ToThebesRect())) { + // Transform it up to user space of the <text> + gfxMatrix m = run.GetTransformFromRunUserSpaceToUserSpace(presContext); + gfxRect rectInUserSpace = m.TransformRect(rectInFrameUserSpace); + + // Union it into the result. + result.UnionRect(result, rectInUserSpace); + } + } + + // Subtract the mRect offset from the result, as our user space for + // this frame is relative to the top-left of mRect. + float factor = AppUnitsPerCSSPixel(); + gfxPoint framePosition(NSAppUnitsToFloatPixels(mRect.x, factor), + NSAppUnitsToFloatPixels(mRect.y, factor)); + + return result - framePosition; +} + +Rect SVGTextFrame::TransformFrameRectFromTextChild( + const Rect& aRect, const nsIFrame* aChildFrame) { + nscoord appUnitsPerDevPixel = PresContext()->AppUnitsPerDevPixel(); + nsRect r = LayoutDevicePixel::ToAppUnits( + LayoutDeviceRect::FromUnknownRect(aRect), appUnitsPerDevPixel); + gfxRect resultCssUnits = TransformFrameRectFromTextChild(r, aChildFrame); + float devPixelPerCSSPixel = + float(AppUnitsPerCSSPixel()) / appUnitsPerDevPixel; + resultCssUnits.Scale(devPixelPerCSSPixel); + return ToRect(resultCssUnits); +} + +Point SVGTextFrame::TransformFramePointFromTextChild( + const Point& aPoint, const nsIFrame* aChildFrame) { + return TransformFrameRectFromTextChild(Rect(aPoint, Size(1, 1)), aChildFrame) + .TopLeft(); +} + +void SVGTextFrame::AppendDirectlyOwnedAnonBoxes( + nsTArray<OwnedAnonBox>& aResult) { + MOZ_ASSERT(PrincipalChildList().FirstChild(), "Must have our anon box"); + aResult.AppendElement(OwnedAnonBox(PrincipalChildList().FirstChild())); +} + +} // namespace mozilla |