SkShaderMaskFilterImpl Class Reference

#include <SkShaderMaskFilterImpl.h>

Inheritance diagram for SkShaderMaskFilterImpl:

Public Member Functions
	SkShaderMaskFilterImpl (sk_sp< SkShader > shader)
SkMask::Format	getFormat () const override
SkMaskFilterBase::Type	type () const override
bool	filterMask (SkMaskBuilder *dst, const SkMask &src, const SkMatrix &, SkIPoint *margin) const override
void	computeFastBounds (const SkRect &src, SkRect *dst) const override
bool	asABlur (BlurRec *) const override
sk_sp< SkShader >	shader () const
Public Member Functions inherited from SkMaskFilterBase
virtual sk_sp< SkImageFilter >	asImageFilter (const SkMatrix &ctm) const
SkFlattenable::Type	getFlattenableType () const override
Public Member Functions inherited from SkMaskFilter
SkRect	approximateFilteredBounds (const SkRect &src) const
Public Member Functions inherited from SkFlattenable
	SkFlattenable ()
virtual Factory	getFactory () const =0
virtual const char *	getTypeName () const =0
sk_sp< SkData >	serialize (const SkSerialProcs *=nullptr) const
size_t	serialize (void *memory, size_t memory_size, const SkSerialProcs *=nullptr) const
Public Member Functions inherited from SkRefCntBase
	SkRefCntBase ()
virtual	~SkRefCntBase ()
bool	unique () const
void	ref () const
void	unref () const

Private Member Functions
void	flatten (SkWriteBuffer &) const override

Friends
class	SkShaderMaskFilter

Additional Inherited Members
Public Types inherited from SkMaskFilterBase
enum class	Type {   kBlur , kEmboss , kSDF , kShader ,   kTable }
Public Types inherited from SkFlattenable
enum	Type {   kSkColorFilter_Type , kSkBlender_Type , kSkDrawable_Type , kSkDrawLooper_Type ,   kSkImageFilter_Type , kSkMaskFilter_Type , kSkPathEffect_Type , kSkShader_Type }
typedef sk_sp< SkFlattenable >(*	Factory) (SkReadBuffer &)
Static Public Member Functions inherited from SkMaskFilterBase
static SkFlattenable::Type	GetFlattenableType ()
Static Public Member Functions inherited from SkMaskFilter
static sk_sp< SkMaskFilter >	MakeBlur (SkBlurStyle style, SkScalar sigma, bool respectCTM=true)
static sk_sp< SkMaskFilter >	Deserialize (const void *data, size_t size, const SkDeserialProcs *procs=nullptr)
Static Public Member Functions inherited from SkFlattenable
static Factory	NameToFactory (const char name[])
static const char *	FactoryToName (Factory)
static void	Register (const char name[], Factory)
static sk_sp< SkFlattenable >	Deserialize (Type, const void *data, size_t length, const SkDeserialProcs *procs=nullptr)
Protected Types inherited from SkMaskFilterBase
enum	FilterReturn { kFalse_FilterReturn , kTrue_FilterReturn , kUnimplemented_FilterReturn }
Protected Member Functions inherited from SkMaskFilterBase
	SkMaskFilterBase ()
virtual FilterReturn	filterRectsToNine (const SkRect[], int count, const SkMatrix &, const SkIRect &clipBounds, SkTLazy< NinePatch > *) const
virtual FilterReturn	filterRRectToNine (const SkRRect &, const SkMatrix &, const SkIRect &clipBounds, SkTLazy< NinePatch > *) const

Detailed Description

Definition at line 25 of file SkShaderMaskFilterImpl.h.

Constructor & Destructor Documentation

SkShaderMaskFilterImpl()

SkShaderMaskFilterImpl::SkShaderMaskFilterImpl ( sk_sp< SkShader >  shader )

inline

Definition at line 27 of file SkShaderMaskFilterImpl.h.

: fShader(std::move(shader)) {}

Member Function Documentation

asABlur()

bool SkShaderMaskFilterImpl::asABlur ( BlurRec *  ) const

inlineoverridevirtual

If this filter can be represented by a BlurRec, return true and (if not null) fill in the provided BlurRec parameter. If this effect cannot be represented as a BlurRec, return false and ignore the BlurRec parameter.

Reimplemented from SkMaskFilterBase.

Definition at line 39 of file SkShaderMaskFilterImpl.h.

{ return false; }

computeFastBounds()

void SkShaderMaskFilterImpl::computeFastBounds ( const SkRect &  src, SkRect *  dest  ) const

inlineoverridevirtual

The fast bounds function is used to enable the paint to be culled early in the drawing pipeline. This function accepts the current bounds of the paint as its src param and the filter adjust those bounds using its current mask and returns the result using the dest param. Callers are allowed to provide the same struct for both src and dest so each implementation must accommodate that behavior.

The default impl calls filterMask with the src mask having no image, but subclasses may override this if they can compute the rect faster.

Reimplemented from SkMaskFilterBase.

Definition at line 35 of file SkShaderMaskFilterImpl.h.

                                                                          {
        *dst = src;
    }

filterMask()

bool SkShaderMaskFilterImpl::filterMask ( SkMaskBuilder *  dst, const SkMask &  src, const SkMatrix &  , SkIPoint *  margin  ) const

overridevirtual

Create a new mask by filter the src mask. If src.fImage == null, then do not allocate or create the dst image but do fill out the other fields in dstMask. If you do allocate a dst image, use SkMask::AllocImage() If this returns false, dst mask is ignored.

Parameters

dst	the result of the filter. If src.fImage == null, dst should not allocate its image
src	the original image to be filtered.
matrix	the CTM
margin	if not null, return the buffer dx/dy need when calculating the effect. Used when drawing a clipped object to know how much larger to allocate the src before applying the filter. If returning false, ignore this parameter.

Returns

true if the dst mask was correctly created.

Implements SkMaskFilterBase.

Definition at line 49 of file SkShaderMaskFilterImpl.cpp.

                                                                {
    if (src.fFormat != SkMask::kA8_Format) {
        return false;
    }
 
    if (margin) {
        margin->set(0, 0);
    }
    dst->bounds()   = src.fBounds;
    dst->rowBytes() = src.fBounds.width();   // need alignment?
    dst->format()   = SkMask::kA8_Format;
 
    if (src.fImage == nullptr) {
        dst->image() = nullptr;
        return true;
    }
    size_t size = dst->computeImageSize();
    if (0 == size) {
        return false;   // too big to allocate, abort
    }
 
    // Allocate and initialize dst image with a copy of the src image
    dst->image() = SkMaskBuilder::AllocImage(size);
    rect_memcpy(dst->image(), dst->fRowBytes, src.fImage, src.fRowBytes,
                src.fBounds.width() * sizeof(uint8_t), src.fBounds.height());
 
    // Now we have a dst-mask, just need to setup a canvas and draw into it
    SkBitmap bitmap;
    if (!bitmap.installMaskPixels(*dst)) {
        return false;
    }
 
    SkPaint paint;
    paint.setShader(fShader);
    // this blendmode is the trick: we only draw the shader where the mask is
    paint.setBlendMode(SkBlendMode::kSrcIn);
 
    SkCanvas canvas(bitmap);
    canvas.translate(-SkIntToScalar(dst->fBounds.fLeft), -SkIntToScalar(dst->fBounds.fTop));
    canvas.concat(ctm);
    canvas.drawPaint(paint);
    return true;
}

flatten()

void SkShaderMaskFilterImpl::flatten ( SkWriteBuffer &  ) const

overrideprivatevirtual

Override this if your subclass needs to record data that it will need to recreate itself from its CreateProc (returned by getFactory()).

DEPRECATED public : will move to protected ... use serialize() instead

Reimplemented from SkFlattenable.

Definition at line 36 of file SkShaderMaskFilterImpl.cpp.

                                                                {
    buffer.writeFlattenable(fShader.get());
}

getFormat()

SkMask::Format SkShaderMaskFilterImpl::getFormat ( ) const

inlineoverridevirtual

Returns the format of the resulting mask that this subclass will return when its filterMask() method is called.

Implements SkMaskFilterBase.

Definition at line 29 of file SkShaderMaskFilterImpl.h.

{ return SkMask::kA8_Format; }

shader()

sk_sp< SkShader > SkShaderMaskFilterImpl::shader ( ) const

inline

Definition at line 40 of file SkShaderMaskFilterImpl.h.

{ return fShader; }

type()

SkMaskFilterBase::Type SkShaderMaskFilterImpl::type ( ) const

inlineoverridevirtual

Implements SkMaskFilterBase.

Definition at line 30 of file SkShaderMaskFilterImpl.h.

{ return SkMaskFilterBase::Type::kShader; }

Friends And Related Symbol Documentation

SkShaderMaskFilter

friend class SkShaderMaskFilter

friend

Definition at line 50 of file SkShaderMaskFilterImpl.h.

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

• third_party/skia/src/effects/SkShaderMaskFilterImpl.h
• third_party/skia/src/effects/SkShaderMaskFilterImpl.cpp