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d85d3ab378
The DrawResult return was not in fact anything to do with the success or failure of that method, but was actually passing out a very specific piece of information about the success or failure of any imagelib drawing that may not have occurred under the various PaintSVG calls. The signature of PaintSVG is changed from DrawResult PaintSVG(...., uint32 flags); to void PaintSVG(...., imgDrawingParams& aPackage); imgDrawingParams wraps DrawResult and imgIContainer::FLAG_* as a pack, pass through PaintSVG to imagelib draw calls under beneath. MozReview-Commit-ID: IOq2evUAOQF
607 lines
20 KiB
C++
607 lines
20 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#ifndef MOZILLA_SVGTEXTFRAME_H
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#define MOZILLA_SVGTEXTFRAME_H
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#include "mozilla/Attributes.h"
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#include "mozilla/RefPtr.h"
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#include "mozilla/gfx/2D.h"
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#include "gfxMatrix.h"
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#include "gfxRect.h"
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#include "gfxTextRun.h"
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#include "nsAutoPtr.h"
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#include "nsIContent.h" // for GetContent
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#include "nsStubMutationObserver.h"
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#include "nsSVGContainerFrame.h"
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class gfxContext;
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class nsDisplaySVGText;
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class SVGTextFrame;
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class nsTextFrame;
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namespace mozilla {
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class CharIterator;
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class nsISVGPoint;
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class TextFrameIterator;
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class TextNodeCorrespondenceRecorder;
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struct TextRenderedRun;
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class TextRenderedRunIterator;
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namespace dom {
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class SVGIRect;
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class SVGPathElement;
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} // namespace dom
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/**
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* Information about the positioning for a single character in an SVG <text>
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* element.
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*
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* During SVG text layout, we use infinity values to represent positions and
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* rotations that are not explicitly specified with x/y/rotate attributes.
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*/
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struct CharPosition
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{
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CharPosition()
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: mAngle(0),
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mHidden(false),
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mUnaddressable(false),
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mClusterOrLigatureGroupMiddle(false),
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mRunBoundary(false),
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mStartOfChunk(false)
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{
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}
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CharPosition(gfxPoint aPosition, double aAngle)
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: mPosition(aPosition),
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mAngle(aAngle),
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mHidden(false),
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mUnaddressable(false),
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mClusterOrLigatureGroupMiddle(false),
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mRunBoundary(false),
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mStartOfChunk(false)
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{
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}
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static CharPosition Unspecified(bool aUnaddressable)
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{
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CharPosition cp(UnspecifiedPoint(), UnspecifiedAngle());
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cp.mUnaddressable = aUnaddressable;
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return cp;
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}
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bool IsAngleSpecified() const
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{
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return mAngle != UnspecifiedAngle();
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}
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bool IsXSpecified() const
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{
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return mPosition.x != UnspecifiedCoord();
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}
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bool IsYSpecified() const
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{
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return mPosition.y != UnspecifiedCoord();
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}
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gfxPoint mPosition;
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double mAngle;
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// not displayed due to falling off the end of a <textPath>
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bool mHidden;
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// skipped in positioning attributes due to being collapsed-away white space
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bool mUnaddressable;
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// a preceding character is what positioning attributes address
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bool mClusterOrLigatureGroupMiddle;
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// rendering is split here since an explicit position or rotation was given
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bool mRunBoundary;
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// an anchored chunk begins here
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bool mStartOfChunk;
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private:
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static gfxFloat UnspecifiedCoord()
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{
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return std::numeric_limits<gfxFloat>::infinity();
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}
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static double UnspecifiedAngle()
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{
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return std::numeric_limits<double>::infinity();
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}
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static gfxPoint UnspecifiedPoint()
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{
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return gfxPoint(UnspecifiedCoord(), UnspecifiedCoord());
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}
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};
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/**
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* A runnable to mark glyph positions as needing to be recomputed
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* and to invalid the bounds of the SVGTextFrame frame.
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*/
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class GlyphMetricsUpdater : public Runnable {
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public:
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NS_DECL_NSIRUNNABLE
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explicit GlyphMetricsUpdater(SVGTextFrame* aFrame) : mFrame(aFrame) { }
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static void Run(SVGTextFrame* aFrame);
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void Revoke() { mFrame = nullptr; }
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private:
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SVGTextFrame* mFrame;
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};
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} // namespace mozilla
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/**
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* Frame class for SVG <text> elements.
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*
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* An SVGTextFrame manages SVG text layout, painting and interaction for
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* all descendent text content elements. The frame tree will look like this:
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*
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* SVGTextFrame -- for <text>
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* <anonymous block frame>
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* ns{Block,Inline,Text}Frames -- for text nodes, <tspan>s, <a>s, etc.
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*
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* SVG text layout is done by:
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*
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* 1. Reflowing the anonymous block frame.
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* 2. Inspecting the (app unit) positions of the glyph for each character in
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* the nsTextFrames underneath the anonymous block frame.
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* 3. Determining the (user unit) positions for each character in the <text>
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* using the x/y/dx/dy/rotate attributes on all the text content elements,
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* and using the step 2 results to fill in any gaps.
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* 4. Applying any other SVG specific text layout (anchoring and text paths)
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* to the positions computed in step 3.
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*
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* Rendering of the text is done by splitting up each nsTextFrame into ranges
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* that can be contiguously painted. (For example <text x="10 20">abcd</text>
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* would have two contiguous ranges: one for the "a" and one for the "bcd".)
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* Each range is called a "text rendered run", represented by a TextRenderedRun
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* object. The TextRenderedRunIterator class performs that splitting and
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* returns a TextRenderedRun for each bit of text to be painted separately.
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*
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* Each rendered run is painted by calling nsTextFrame::PaintText. If the text
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* formatting is simple enough (solid fill, no stroking, etc.), PaintText will
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* itself do the painting. Otherwise, a DrawPathCallback is passed to
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* PaintText so that we can fill the text geometry with SVG paint servers.
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*/
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class SVGTextFrame final : public nsSVGDisplayContainerFrame
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{
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friend nsIFrame*
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NS_NewSVGTextFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
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friend class mozilla::CharIterator;
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friend class mozilla::GlyphMetricsUpdater;
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friend class mozilla::TextFrameIterator;
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friend class mozilla::TextNodeCorrespondenceRecorder;
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friend struct mozilla::TextRenderedRun;
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friend class mozilla::TextRenderedRunIterator;
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friend class MutationObserver;
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friend class nsDisplaySVGText;
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typedef gfxTextRun::Range Range;
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typedef mozilla::gfx::DrawTarget DrawTarget;
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typedef mozilla::gfx::Path Path;
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typedef mozilla::gfx::Point Point;
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typedef mozilla::image::DrawResult DrawResult;
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protected:
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explicit SVGTextFrame(nsStyleContext* aContext)
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: nsSVGDisplayContainerFrame(aContext, mozilla::LayoutFrameType::SVGText)
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, mTrailingUndisplayedCharacters(0)
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, mFontSizeScaleFactor(1.0f)
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, mLastContextScale(1.0f)
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, mLengthAdjustScaleFactor(1.0f)
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{
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AddStateBits(NS_STATE_SVG_POSITIONING_DIRTY);
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}
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~SVGTextFrame() {}
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public:
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NS_DECL_QUERYFRAME_TARGET(SVGTextFrame)
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NS_DECL_QUERYFRAME
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NS_DECL_FRAMEARENA_HELPERS
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// nsIFrame:
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virtual void Init(nsIContent* aContent,
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nsContainerFrame* aParent,
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nsIFrame* aPrevInFlow) override;
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virtual nsresult AttributeChanged(int32_t aNamespaceID,
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nsIAtom* aAttribute,
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int32_t aModType) override;
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virtual nsContainerFrame* GetContentInsertionFrame() override
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{
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return PrincipalChildList().FirstChild()->GetContentInsertionFrame();
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}
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virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
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const nsRect& aDirtyRect,
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const nsDisplayListSet& aLists) override;
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#ifdef DEBUG_FRAME_DUMP
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virtual nsresult GetFrameName(nsAString& aResult) const override
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{
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return MakeFrameName(NS_LITERAL_STRING("SVGText"), aResult);
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}
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#endif
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virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext) override;
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/**
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* Finds the nsTextFrame for the closest rendered run to the specified point.
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*/
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virtual void FindCloserFrameForSelection(nsPoint aPoint,
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FrameWithDistance* aCurrentBestFrame) override;
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// nsSVGDisplayableFrame interface:
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virtual void NotifySVGChanged(uint32_t aFlags) override;
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virtual void PaintSVG(gfxContext& aContext,
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const gfxMatrix& aTransform,
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imgDrawingParams& aImgParams,
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const nsIntRect* aDirtyRect = nullptr) override;
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virtual nsIFrame* GetFrameForPoint(const gfxPoint& aPoint) override;
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virtual void ReflowSVG() override;
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virtual SVGBBox GetBBoxContribution(const Matrix& aToBBoxUserspace,
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uint32_t aFlags) override;
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// nsSVGContainerFrame methods:
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virtual gfxMatrix GetCanvasTM() override;
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// SVG DOM text methods:
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uint32_t GetNumberOfChars(nsIContent* aContent);
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float GetComputedTextLength(nsIContent* aContent);
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nsresult SelectSubString(nsIContent* aContent, uint32_t charnum, uint32_t nchars);
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nsresult GetSubStringLength(nsIContent* aContent, uint32_t charnum,
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uint32_t nchars, float* aResult);
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int32_t GetCharNumAtPosition(nsIContent* aContent, mozilla::nsISVGPoint* point);
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nsresult GetStartPositionOfChar(nsIContent* aContent, uint32_t aCharNum,
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mozilla::nsISVGPoint** aResult);
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nsresult GetEndPositionOfChar(nsIContent* aContent, uint32_t aCharNum,
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mozilla::nsISVGPoint** aResult);
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nsresult GetExtentOfChar(nsIContent* aContent, uint32_t aCharNum,
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mozilla::dom::SVGIRect** aResult);
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nsresult GetRotationOfChar(nsIContent* aContent, uint32_t aCharNum,
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float* aResult);
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// SVGTextFrame methods:
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/**
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* Handles a base or animated attribute value change to a descendant
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* text content element.
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*/
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void HandleAttributeChangeInDescendant(mozilla::dom::Element* aElement,
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int32_t aNameSpaceID,
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nsIAtom* aAttribute);
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/**
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* Schedules mPositions to be recomputed and the covered region to be
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* updated.
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*/
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void NotifyGlyphMetricsChange();
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/**
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* Calls ScheduleReflowSVGNonDisplayText if this is a non-display frame,
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* and nsSVGUtils::ScheduleReflowSVG otherwise.
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*/
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void ScheduleReflowSVG();
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/**
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* Reflows the anonymous block frame of this non-display SVGTextFrame.
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*
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* When we are under nsSVGDisplayContainerFrame::ReflowSVG, we need to
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* reflow any SVGTextFrame frames in the subtree in case they are
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* being observed (by being for example in a <mask>) and the change
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* that caused the reflow would not already have caused a reflow.
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*
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* Note that displayed SVGTextFrames are reflowed as needed, when PaintSVG
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* is called or some SVG DOM method is called on the element.
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*/
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void ReflowSVGNonDisplayText();
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/**
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* This is a function that behaves similarly to nsSVGUtils::ScheduleReflowSVG,
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* but which will skip over any ancestor non-display container frames on the
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* way to the nsSVGOuterSVGFrame. It exists for the situation where a
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* non-display <text> element has changed and needs to ensure ReflowSVG will
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* be called on its closest display container frame, so that
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* nsSVGDisplayContainerFrame::ReflowSVG will call ReflowSVGNonDisplayText on
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* it.
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*
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* We have to do this in two cases: in response to a style change on a
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* non-display <text>, where aReason will be eStyleChange (the common case),
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* and also in response to glyphs changes on non-display <text> (i.e.,
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* animated SVG-in-OpenType glyphs), in which case aReason will be eResize,
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* since layout doesn't need to be recomputed.
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*/
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void ScheduleReflowSVGNonDisplayText(nsIPresShell::IntrinsicDirty aReason);
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/**
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* Updates the mFontSizeScaleFactor value by looking at the range of
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* font-sizes used within the <text>.
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*
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* @return Whether mFontSizeScaleFactor changed.
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*/
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bool UpdateFontSizeScaleFactor();
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double GetFontSizeScaleFactor() const;
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/**
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* Takes a point from the <text> element's user space and
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* converts it to the appropriate frame user space of aChildFrame,
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* according to which rendered run the point hits.
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*/
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Point TransformFramePointToTextChild(const Point& aPoint,
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nsIFrame* aChildFrame);
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/**
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* Takes a rectangle, aRect, in the <text> element's user space, and
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* returns a rectangle in aChildFrame's frame user space that
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* covers intersections of aRect with each rendered run for text frames
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* within aChildFrame.
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*/
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gfxRect TransformFrameRectToTextChild(const gfxRect& aRect,
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nsIFrame* aChildFrame);
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/**
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* Takes an app unit rectangle in the coordinate space of a given descendant
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* frame of this frame, and returns a rectangle in the <text> element's user
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* space that covers all parts of rendered runs that intersect with the
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* rectangle.
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*/
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gfxRect TransformFrameRectFromTextChild(const nsRect& aRect,
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nsIFrame* aChildFrame);
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/**
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* Update the style of our ::-moz-svg-text anonymous box.
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*/
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void DoUpdateStyleOfOwnedAnonBoxes(mozilla::ServoStyleSet& aStyleSet,
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nsStyleChangeList& aChangeList,
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nsChangeHint aHintForThisFrame) override;
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private:
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/**
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* Mutation observer used to watch for text positioning attribute changes
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* on descendent text content elements (like <tspan>s).
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*/
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class MutationObserver final : public nsStubMutationObserver {
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public:
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explicit MutationObserver(SVGTextFrame* aFrame)
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: mFrame(aFrame)
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{
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MOZ_ASSERT(mFrame, "MutationObserver needs a non-null frame");
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mFrame->GetContent()->AddMutationObserver(this);
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}
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// nsISupports
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NS_DECL_ISUPPORTS
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// nsIMutationObserver
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NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
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NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
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NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
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NS_DECL_NSIMUTATIONOBSERVER_CHARACTERDATACHANGED
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NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
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private:
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~MutationObserver()
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{
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mFrame->GetContent()->RemoveMutationObserver(this);
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}
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SVGTextFrame* const mFrame;
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};
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/**
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* Reflows the anonymous block child if it is dirty or has dirty
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* children, or if the SVGTextFrame itself is dirty.
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*/
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void MaybeReflowAnonymousBlockChild();
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/**
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* Performs the actual work of reflowing the anonymous block child.
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*/
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void DoReflow();
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/**
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* Recomputes mPositions by calling DoGlyphPositioning if this information
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* is out of date.
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*/
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void UpdateGlyphPositioning();
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/**
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* Populates mPositions with positioning information for each character
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* within the <text>.
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*/
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void DoGlyphPositioning();
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/**
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* Converts the specified index into mPositions to an addressable
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* character index (as can be used with the SVG DOM text methods)
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* relative to the specified text child content element.
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*
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* @param aIndex The global character index.
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* @param aContent The descendant text child content element that
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* the returned addressable index will be relative to; null
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* means the same as the <text> element.
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* @return The addressable index, or -1 if the index cannot be
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* represented as an addressable index relative to aContent.
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*/
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int32_t
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ConvertTextElementCharIndexToAddressableIndex(int32_t aIndex,
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nsIContent* aContent);
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/**
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* Recursive helper for ResolvePositions below.
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*
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* @param aContent The current node.
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* @param aIndex (in/out) The current character index.
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* @param aInTextPath Whether we are currently under a <textPath> element.
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* @param aForceStartOfChunk (in/out) Whether the next character we find
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* should start a new anchored chunk.
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* @param aDeltas (in/out) Receives the resolved dx/dy values for each
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* character.
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* @return false if we discover that mPositions did not have enough
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* elements; true otherwise.
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*/
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bool ResolvePositionsForNode(nsIContent* aContent, uint32_t& aIndex,
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bool aInTextPath, bool& aForceStartOfChunk,
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nsTArray<gfxPoint>& aDeltas);
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/**
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* Initializes mPositions with character position information based on
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* x/y/rotate attributes, leaving unspecified values in the array if a position
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* was not given for that character. Also fills aDeltas with values based on
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* dx/dy attributes.
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*
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* @param aDeltas (in/out) Receives the resolved dx/dy values for each
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* character.
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* @param aRunPerGlyph Whether mPositions should record that a new run begins
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* at each glyph.
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* @return false if we did not record any positions (due to having no
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* displayed characters) or if we discover that mPositions did not have
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* enough elements; true otherwise.
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*/
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bool ResolvePositions(nsTArray<gfxPoint>& aDeltas, bool aRunPerGlyph);
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/**
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* Determines the position, in app units, of each character in the <text> as
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* laid out by reflow, and appends them to aPositions. Any characters that
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* are undisplayed or trimmed away just get the last position.
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*/
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void DetermineCharPositions(nsTArray<nsPoint>& aPositions);
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/**
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* Sets mStartOfChunk to true for each character in mPositions that starts a
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* line of text.
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*/
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void AdjustChunksForLineBreaks();
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/**
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* Adjusts recorded character positions in mPositions to account for glyph
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* boundaries. Four things are done:
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*
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* 1. mClusterOrLigatureGroupMiddle is set to true for all such characters.
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*
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* 2. Any run and anchored chunk boundaries that begin in the middle of a
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* cluster/ligature group get moved to the start of the next
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* cluster/ligature group.
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*
|
|
* 3. The position of any character in the middle of a cluster/ligature
|
|
* group is updated to take into account partial ligatures and any
|
|
* rotation the glyph as a whole has. (The values that come out of
|
|
* DetermineCharPositions which then get written into mPositions in
|
|
* ResolvePositions store the same position value for each part of the
|
|
* ligature.)
|
|
*
|
|
* 4. The rotation of any character in the middle of a cluster/ligature
|
|
* group is set to the rotation of the first character.
|
|
*/
|
|
void AdjustPositionsForClusters();
|
|
|
|
/**
|
|
* Updates the character positions stored in mPositions to account for
|
|
* text anchoring.
|
|
*/
|
|
void DoAnchoring();
|
|
|
|
/**
|
|
* Updates character positions in mPositions for those characters inside a
|
|
* <textPath>.
|
|
*/
|
|
void DoTextPathLayout();
|
|
|
|
/**
|
|
* Returns whether we need to render the text using
|
|
* nsTextFrame::DrawPathCallbacks rather than directly painting
|
|
* the text frames.
|
|
*
|
|
* @param aShouldPaintSVGGlyphs (out) Whether SVG glyphs in the text
|
|
* should be painted.
|
|
*/
|
|
bool ShouldRenderAsPath(nsTextFrame* aFrame, bool& aShouldPaintSVGGlyphs);
|
|
|
|
// Methods to get information for a <textPath> frame.
|
|
mozilla::dom::SVGPathElement*
|
|
GetTextPathPathElement(nsIFrame* aTextPathFrame);
|
|
already_AddRefed<Path> GetTextPath(nsIFrame* aTextPathFrame);
|
|
gfxFloat GetOffsetScale(nsIFrame* aTextPathFrame);
|
|
gfxFloat GetStartOffset(nsIFrame* aTextPathFrame);
|
|
|
|
/**
|
|
* The MutationObserver we have registered for the <text> element subtree.
|
|
*/
|
|
RefPtr<MutationObserver> mMutationObserver;
|
|
|
|
/**
|
|
* Cached canvasTM value.
|
|
*/
|
|
nsAutoPtr<gfxMatrix> mCanvasTM;
|
|
|
|
/**
|
|
* The number of characters in the DOM after the final nsTextFrame. For
|
|
* example, with
|
|
*
|
|
* <text>abcd<tspan display="none">ef</tspan></text>
|
|
*
|
|
* mTrailingUndisplayedCharacters would be 2.
|
|
*/
|
|
uint32_t mTrailingUndisplayedCharacters;
|
|
|
|
/**
|
|
* Computed position information for each DOM character within the <text>.
|
|
*/
|
|
nsTArray<mozilla::CharPosition> mPositions;
|
|
|
|
/**
|
|
* mFontSizeScaleFactor is used to cause the nsTextFrames to create text
|
|
* runs with a font size different from the actual font-size property value.
|
|
* This is used so that, for example with:
|
|
*
|
|
* <svg>
|
|
* <g transform="scale(2)">
|
|
* <text font-size="10">abc</text>
|
|
* </g>
|
|
* </svg>
|
|
*
|
|
* a font size of 20 would be used. It's preferable to use a font size that
|
|
* is identical or close to the size that the text will appear on the screen,
|
|
* because at very small or large font sizes, text metrics will be computed
|
|
* differently due to the limited precision that text runs have.
|
|
*
|
|
* mFontSizeScaleFactor is the amount the actual font-size property value
|
|
* should be multiplied by to cause the text run font size to (a) be within a
|
|
* "reasonable" range, and (b) be close to the actual size to be painted on
|
|
* screen. (The "reasonable" range as determined by some #defines in
|
|
* SVGTextFrame.cpp is 8..200.)
|
|
*/
|
|
float mFontSizeScaleFactor;
|
|
|
|
/**
|
|
* The scale of the context that we last used to compute mFontSizeScaleFactor.
|
|
* We record this so that we can tell when our scale transform has changed
|
|
* enough to warrant reflowing the text.
|
|
*/
|
|
float mLastContextScale;
|
|
|
|
/**
|
|
* The amount that we need to scale each rendered run to account for
|
|
* lengthAdjust="spacingAndGlyphs".
|
|
*/
|
|
float mLengthAdjustScaleFactor;
|
|
};
|
|
|
|
#endif
|