CircleOp Class Reference

Inheritance diagram for CircleOp:

Classes
struct	ArcParams

Public Member Functions
	CircleOp (GrProcessorSet *processorSet, const SkPMColor4f &color, const SkMatrix &viewMatrix, SkPoint center, SkScalar radius, const GrStyle &style, const ArcParams *arcParams)
const char *	name () const override
void	visitProxies (const GrVisitProxyFunc &func) const override
GrProcessorSet::Analysis	finalize (const GrCaps &caps, const GrAppliedClip *clip, GrClampType clampType) override
FixedFunctionFlags	fixedFunctionFlags () const override
Public Member Functions inherited from GrDrawOp
	GrDrawOp (uint32_t classID)
virtual bool	usesMSAA () const
virtual ClipResult	clipToShape (skgpu::ganesh::SurfaceDrawContext *, SkClipOp, const SkMatrix &, const GrShape &, GrAA)
virtual GrProcessorSet::Analysis	finalize (const GrCaps &, const GrAppliedClip *, GrClampType)=0
virtual bool	usesStencil () const
Public Member Functions inherited from GrOp
virtual	~GrOp ()=default
virtual const char *	name () const =0
virtual void	visitProxies (const GrVisitProxyFunc &) const
CombineResult	combineIfPossible (GrOp *that, SkArenaAlloc *alloc, const GrCaps &caps)
const SkRect &	bounds () const
void	setClippedBounds (const SkRect &clippedBounds)
bool	hasAABloat () const
bool	hasZeroArea () const
void	operator delete (void *p)
template<typename T >
const T &	cast () const
template<typename T >
T *	cast ()
uint32_t	classID () const
uint32_t	uniqueID () const
void	prePrepare (GrRecordingContext *context, const GrSurfaceProxyView &dstView, GrAppliedClip *clip, const GrDstProxyView &dstProxyView, GrXferBarrierFlags renderPassXferBarriers, GrLoadOp colorLoadOp)
void	prepare (GrOpFlushState *state)
void	execute (GrOpFlushState *state, const SkRect &chainBounds)
void	chainConcat (GrOp::Owner)
bool	isChainHead () const
bool	isChainTail () const
GrOp *	nextInChain () const
GrOp *	prevInChain () const
GrOp::Owner	cutChain ()
void	setBounds (const SkRect &newBounds, HasAABloat aabloat, IsHairline zeroArea)
void	setTransformedBounds (const SkRect &srcBounds, const SkMatrix &m, HasAABloat aabloat, IsHairline zeroArea)
void	makeFullScreen (GrSurfaceProxy *proxy)

Static Public Member Functions
static GrOp::Owner	Make (GrRecordingContext *context, GrPaint &&paint, const SkMatrix &viewMatrix, SkPoint center, SkScalar radius, const GrStyle &style, const ArcParams *arcParams=nullptr)
Static Public Member Functions inherited from GrMeshDrawOp
static bool	CanUpgradeAAOnMerge (GrAAType aa1, GrAAType aa2)
Static Public Member Functions inherited from GrOp
template<typename Op , typename... Args>
static Owner	Make (GrRecordingContext *context, Args &&... args)
template<typename Op , typename... Args>
static Owner	MakeWithProcessorSet (GrRecordingContext *context, const SkPMColor4f &color, GrPaint &&paint, Args &&... args)
template<typename Op , typename... Args>
static Owner	MakeWithExtraMemory (GrRecordingContext *context, size_t extraSize, Args &&... args)
static uint32_t	GenOpClassID ()

Additional Inherited Members
Public Types inherited from GrDrawOp
enum class	ClipResult { kFail , kClippedGeometrically , kClippedInShader , kClippedOut }
Public Types inherited from GrOp
enum class	CombineResult { kMerged , kMayChain , kCannotCombine }
enum class	HasAABloat : bool { kNo = false , kYes = true }
enum class	IsHairline : bool { kNo = false , kYes = true }
using	Owner = std::unique_ptr< GrOp >
Protected Types inherited from GrDrawOp
enum class	FixedFunctionFlags : uint32_t { kNone = 0x0 , kUsesHWAA = 0x1 , kUsesStencil = 0x2 }
Protected Member Functions inherited from GrMeshDrawOp
	GrMeshDrawOp (uint32_t classID)
void	createProgramInfo (const GrCaps *caps, SkArenaAlloc *arena, const GrSurfaceProxyView &writeView, bool usesMSAASurface, GrAppliedClip &&appliedClip, const GrDstProxyView &dstProxyView, GrXferBarrierFlags renderPassXferBarriers, GrLoadOp colorLoadOp)
void	createProgramInfo (GrMeshDrawTarget *)
virtual void	onPrePrepareDraws (GrRecordingContext *, const GrSurfaceProxyView &writeView, GrAppliedClip *, const GrDstProxyView &, GrXferBarrierFlags renderPassXferBarriers, GrLoadOp colorLoadOp)
Protected Member Functions inherited from GrDrawOp
	GR_DECL_BITFIELD_CLASS_OPS_FRIENDS (FixedFunctionFlags)
virtual FixedFunctionFlags	fixedFunctionFlags () const
Static Protected Member Functions inherited from GrMeshDrawOp
static bool	CombinedQuadCountWillOverflow (GrAAType aaType, bool willBeUpgradedToAA, int combinedQuadCount)

Detailed Description

Definition at line 985 of file GrOvalOpFactory.cpp.

Constructor & Destructor Documentation

CircleOp()

CircleOp::CircleOp ( GrProcessorSet *  processorSet, const SkPMColor4f &  color, const SkMatrix &  viewMatrix, SkPoint  center, SkScalar  radius, const GrStyle &  style, const ArcParams *  arcParams  )

inline

Definition at line 1041 of file GrOvalOpFactory.cpp.

            : GrMeshDrawOp(ClassID())
            , fHelper(processorSet, GrAAType::kCoverage) {
        const SkStrokeRec& stroke = style.strokeRec();
        SkStrokeRec::Style recStyle = stroke.getStyle();
 
        fRoundCaps = false;
 
        viewMatrix.mapPoints(&center, 1);
        radius = viewMatrix.mapRadius(radius);
        SkScalar strokeWidth = viewMatrix.mapRadius(stroke.getWidth());
 
        bool isStrokeOnly =
                SkStrokeRec::kStroke_Style == recStyle || SkStrokeRec::kHairline_Style == recStyle;
        bool hasStroke = isStrokeOnly || SkStrokeRec::kStrokeAndFill_Style == recStyle;
 
        SkScalar innerRadius = -SK_ScalarHalf;
        SkScalar outerRadius = radius;
        SkScalar halfWidth = 0;
        if (hasStroke) {
            if (SkScalarNearlyZero(strokeWidth)) {
                halfWidth = SK_ScalarHalf;
            } else {
                halfWidth = SkScalarHalf(strokeWidth);
            }
 
            outerRadius += halfWidth;
            if (isStrokeOnly) {
                innerRadius = radius - halfWidth;
            }
        }
 
        // The radii are outset for two reasons. First, it allows the shader to simply perform
        // simpler computation because the computed alpha is zero, rather than 50%, at the radius.
        // Second, the outer radius is used to compute the verts of the bounding box that is
        // rendered and the outset ensures the box will cover all partially covered by the circle.
        outerRadius += SK_ScalarHalf;
        innerRadius -= SK_ScalarHalf;
        bool stroked = isStrokeOnly && innerRadius > 0.0f;
        fViewMatrixIfUsingLocalCoords = viewMatrix;
 
        // This makes every point fully inside the intersection plane.
        static constexpr SkScalar kUnusedIsectPlane[] = {0.f, 0.f, 1.f};
        // This makes every point fully outside the union plane.
        static constexpr SkScalar kUnusedUnionPlane[] = {0.f, 0.f, 0.f};
        static constexpr SkPoint kUnusedRoundCaps[] = {{1e10f, 1e10f}, {1e10f, 1e10f}};
        SkRect devBounds = SkRect::MakeLTRB(center.fX - outerRadius, center.fY - outerRadius,
                                            center.fX + outerRadius, center.fY + outerRadius);
        if (arcParams) {
            // The shader operates in a space where the circle is translated to be centered at the
            // origin. Here we compute points on the unit circle at the starting and ending angles.
            SkPoint startPoint, stopPoint;
            startPoint.fY = SkScalarSin(arcParams->fStartAngleRadians);
            startPoint.fX = SkScalarCos(arcParams->fStartAngleRadians);
            SkScalar endAngle = arcParams->fStartAngleRadians + arcParams->fSweepAngleRadians;
            stopPoint.fY = SkScalarSin(endAngle);
            stopPoint.fX = SkScalarCos(endAngle);
 
            // Adjust the start and end points based on the view matrix (to handle rotated arcs)
            startPoint = viewMatrix.mapVector(startPoint.fX, startPoint.fY);
            stopPoint = viewMatrix.mapVector(stopPoint.fX, stopPoint.fY);
            startPoint.normalize();
            stopPoint.normalize();
 
            // We know the matrix is a similarity here. Detect mirroring which will affect how we
            // should orient the clip planes for arcs.
            SkASSERT(viewMatrix.isSimilarity());
            auto upperLeftDet = viewMatrix.getScaleX()*viewMatrix.getScaleY() -
                                viewMatrix.getSkewX() *viewMatrix.getSkewY();
            if (upperLeftDet < 0) {
                std::swap(startPoint, stopPoint);
            }
 
            fRoundCaps = style.strokeRec().getWidth() > 0 &&
                         style.strokeRec().getCap() == SkPaint::kRound_Cap;
            SkPoint roundCaps[2];
            if (fRoundCaps) {
                // Compute the cap center points in the normalized space.
                SkScalar midRadius = (innerRadius + outerRadius) / (2 * outerRadius);
                roundCaps[0] = startPoint * midRadius;
                roundCaps[1] = stopPoint * midRadius;
            } else {
                roundCaps[0] = kUnusedRoundCaps[0];
                roundCaps[1] = kUnusedRoundCaps[1];
            }
 
            // Like a fill without useCenter, butt-cap stroke can be implemented by clipping against
            // radial lines. We treat round caps the same way, but tack coverage of circles at the
            // center of the butts.
            // However, in both cases we have to be careful about the half-circle.
            // case. In that case the two radial lines are equal and so that edge gets clipped
            // twice. Since the shared edge goes through the center we fall back on the !useCenter
            // case.
            auto absSweep = SkScalarAbs(arcParams->fSweepAngleRadians);
            bool useCenter = (arcParams->fUseCenter || isStrokeOnly) &&
                             !SkScalarNearlyEqual(absSweep, SK_ScalarPI);
            if (useCenter) {
                SkVector norm0 = {startPoint.fY, -startPoint.fX};
                SkVector norm1 = {stopPoint.fY, -stopPoint.fX};
                // This ensures that norm0 is always the clockwise plane, and norm1 is CCW.
                if (arcParams->fSweepAngleRadians < 0) {
                    std::swap(norm0, norm1);
                }
                norm0.negate();
                fClipPlane = true;
                if (absSweep > SK_ScalarPI) {
                    fCircles.emplace_back(Circle{
                            color,
                            innerRadius,
                            outerRadius,
                            {norm0.fX, norm0.fY, 0.5f},
                            {kUnusedIsectPlane[0], kUnusedIsectPlane[1], kUnusedIsectPlane[2]},
                            {norm1.fX, norm1.fY, 0.5f},
                            {roundCaps[0], roundCaps[1]},
                            devBounds,
                            stroked});
                    fClipPlaneIsect = false;
                    fClipPlaneUnion = true;
                } else {
                    fCircles.emplace_back(Circle{
                            color,
                            innerRadius,
                            outerRadius,
                            {norm0.fX, norm0.fY, 0.5f},
                            {norm1.fX, norm1.fY, 0.5f},
                            {kUnusedUnionPlane[0], kUnusedUnionPlane[1], kUnusedUnionPlane[2]},
                            {roundCaps[0], roundCaps[1]},
                            devBounds,
                            stroked});
                    fClipPlaneIsect = true;
                    fClipPlaneUnion = false;
                }
            } else {
                // We clip to a secant of the original circle.
                startPoint.scale(radius);
                stopPoint.scale(radius);
                SkVector norm = {startPoint.fY - stopPoint.fY, stopPoint.fX - startPoint.fX};
                norm.normalize();
                if (arcParams->fSweepAngleRadians > 0) {
                    norm.negate();
                }
                SkScalar d = -norm.dot(startPoint) + 0.5f;
 
                fCircles.emplace_back(
                        Circle{color,
                               innerRadius,
                               outerRadius,
                               {norm.fX, norm.fY, d},
                               {kUnusedIsectPlane[0], kUnusedIsectPlane[1], kUnusedIsectPlane[2]},
                               {kUnusedUnionPlane[0], kUnusedUnionPlane[1], kUnusedUnionPlane[2]},
                               {roundCaps[0], roundCaps[1]},
                               devBounds,
                               stroked});
                fClipPlane = true;
                fClipPlaneIsect = false;
                fClipPlaneUnion = false;
            }
        } else {
            fCircles.emplace_back(
                    Circle{color,
                           innerRadius,
                           outerRadius,
                           {kUnusedIsectPlane[0], kUnusedIsectPlane[1], kUnusedIsectPlane[2]},
                           {kUnusedIsectPlane[0], kUnusedIsectPlane[1], kUnusedIsectPlane[2]},
                           {kUnusedUnionPlane[0], kUnusedUnionPlane[1], kUnusedUnionPlane[2]},
                           {kUnusedRoundCaps[0], kUnusedRoundCaps[1]},
                           devBounds,
                           stroked});
            fClipPlane = false;
            fClipPlaneIsect = false;
            fClipPlaneUnion = false;
        }
        // Use the original radius and stroke radius for the bounds so that it does not include the
        // AA bloat.
        radius += halfWidth;
        this->setBounds(
                {center.fX - radius, center.fY - radius, center.fX + radius, center.fY + radius},
                HasAABloat::kYes, IsHairline::kNo);
        fVertCount = circle_type_to_vert_count(stroked);
        fIndexCount = circle_type_to_index_count(stroked);
        fAllFill = !stroked;
    }

Member Function Documentation

finalize()

GrProcessorSet::Analysis CircleOp::finalize ( const GrCaps &  , const GrAppliedClip *  , GrClampType    )

inlineoverridevirtual

This is called after the GrAppliedClip has been computed and just prior to recording the op or combining it with a previously recorded op. The op should convert any proxies or resources it owns to "pending io" status so that resource allocation can be more optimal. Additionally, at this time the op must report whether a copy of the destination (or destination texture itself) needs to be provided to the GrXferProcessor when this op executes.

Implements GrDrawOp.

Definition at line 1236 of file GrOvalOpFactory.cpp.

                                                                      {
        SkPMColor4f* color = &fCircles.front().fColor;
        return fHelper.finalizeProcessors(caps, clip, clampType,
                                          GrProcessorAnalysisCoverage::kSingleChannel, color,
                                          &fWideColor);
    }

fixedFunctionFlags()

FixedFunctionFlags CircleOp::fixedFunctionFlags ( ) const

inlineoverridevirtual

Reimplemented from GrDrawOp.

Definition at line 1244 of file GrOvalOpFactory.cpp.

{ return fHelper.fixedFunctionFlags(); }

Make()

static GrOp::Owner CircleOp::Make ( GrRecordingContext *  context, GrPaint &&  paint, const SkMatrix &  viewMatrix, SkPoint  center, SkScalar  radius, const GrStyle &  style, const ArcParams *  arcParams = nullptr  )

inlinestatic

Definition at line 999 of file GrOvalOpFactory.cpp.

                                                                  {
        SkASSERT(circle_stays_circle(viewMatrix));
        if (style.hasPathEffect()) {
            return nullptr;
        }
        const SkStrokeRec& stroke = style.strokeRec();
        SkStrokeRec::Style recStyle = stroke.getStyle();
        if (arcParams) {
            // Arc support depends on the style.
            switch (recStyle) {
                case SkStrokeRec::kStrokeAndFill_Style:
                    // This produces a strange result that this op doesn't implement.
                    return nullptr;
                case SkStrokeRec::kFill_Style:
                    // This supports all fills.
                    break;
                case SkStrokeRec::kStroke_Style:
                    // Strokes that don't use the center point are supported with butt and round
                    // caps.
                    if (arcParams->fUseCenter || stroke.getCap() == SkPaint::kSquare_Cap) {
                        return nullptr;
                    }
                    break;
                case SkStrokeRec::kHairline_Style:
                    // Hairline only supports butt cap. Round caps could be emulated by slightly
                    // extending the angle range if we ever care to.
                    if (arcParams->fUseCenter || stroke.getCap() != SkPaint::kButt_Cap) {
                        return nullptr;
                    }
                    break;
            }
        }
        return Helper::FactoryHelper<CircleOp>(context, std::move(paint), viewMatrix, center,
                                               radius, style, arcParams);
    }

name()

const char * CircleOp::name ( ) const

inlineoverridevirtual

Implements GrOp.

Definition at line 1226 of file GrOvalOpFactory.cpp.

{ return "CircleOp"; }

visitProxies()

void CircleOp::visitProxies ( const GrVisitProxyFunc &  func ) const

inlineoverridevirtual

Reimplemented from GrOp.

Definition at line 1228 of file GrOvalOpFactory.cpp.

                                                                   {
        if (fProgramInfo) {
            fProgramInfo->visitFPProxies(func);
        } else {
            fHelper.visitProxies(func);
        }
    }

---

The documentation for this class was generated from the following file:

• third_party/skia/src/gpu/ganesh/ops/GrOvalOpFactory.cpp