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SkPathEffect Class Referenceabstract

SkPathEffect is the base class for objects in the SkPaint that affect the geometry of a drawing primitive before it is transformed by the canvas' matrix and drawn. More...

#include <SkPathEffect.h>

Inheritance diagram for SkPathEffect:
SkFlattenable SkRefCnt SkRefCntBase Sk1DPathEffect Sk2DPathEffect SkArcToPathEffect SkCornerPathEffect SkDiscretePathEffect SkPath1DPathEffect SkLine2DPathEffect SkPath2DPathEffect

Classes

struct  DashInfo
 
class  PointData
 PointData aggregates all the information needed to draw the point primitives returned by an 'asPoints' call. More...
 

Public Types

enum  DashType { kNone_DashType, kDash_DashType }
 If the PathEffect can be represented as a dash pattern, asADash will return kDash_DashType and None otherwise. More...
 
- Public Types inherited from SkFlattenable
enum  Type {
  kSkColorFilter_Type, kSkDrawable_Type, kSkDrawLooper_Type, kSkImageFilter_Type,
  kSkMaskFilter_Type, kSkPathEffect_Type, kSkPixelRef_Type, kSkRasterizer_Type,
  kSkShaderBase_Type, kSkUnused_Type, kSkUnused_Xfermode_Type, kSkNormalSource_Type
}
 
typedef sk_sp< SkFlattenable >(* Factory )(SkReadBuffer &)
 

Public Member Functions

virtual bool filterPath (SkPath *dst, const SkPath &src, SkStrokeRec *, const SkRect *cullR) const =0
 Given a src path (input) and a stroke-rec (input and output), apply this effect to the src path, returning the new path in dst, and return true. More...
 
virtual void computeFastBounds (SkRect *dst, const SkRect &src) const
 Compute a conservative bounds for its effect, given the src bounds. More...
 
virtual bool asPoints (PointData *results, const SkPath &src, const SkStrokeRec &, const SkMatrix &, const SkRect *cullR) const
 Does applying this path effect to 'src' yield a set of points? If so, optionally return the points in 'results'.
 
virtual DashType asADash (DashInfo *info) const
 
- Public Member Functions inherited from SkFlattenable
virtual Factory getFactory () const =0
 Implement this to return a factory function pointer that can be called to recreate your class given a buffer (previously written to by your override of flatten().
 
virtual const char * getTypeName () const
 Returns the name of the object's class. More...
 
virtual void flatten (SkWriteBuffer &) const
 Override this if your subclass needs to record data that it will need to recreate itself from its CreateProc (returned by getFactory()).
 
- Public Member Functions inherited from SkRefCntBase
 SkRefCntBase ()
 Default construct, initializing the reference count to 1.
 
virtual ~SkRefCntBase ()
 Destruct, asserting that the reference count is 1.
 
int32_t getRefCnt () const
 Return the reference count. More...
 
void validate () const
 
bool unique () const
 May return true if the caller is the only owner. More...
 
void ref () const
 Increment the reference count. More...
 
void unref () const
 Decrement the reference count. More...
 

Static Public Member Functions

static sk_sp< SkPathEffectMakeSum (sk_sp< SkPathEffect > first, sk_sp< SkPathEffect > second)
 Returns a patheffect that apples each effect (first and second) to the original path, and returns a path with the sum of these. More...
 
static sk_sp< SkPathEffectMakeCompose (sk_sp< SkPathEffect > outer, sk_sp< SkPathEffect > inner)
 Returns a patheffect that applies the inner effect to the path, and then applies the outer effect to the result of the inner's. More...
 
- Static Public Member Functions inherited from SkFlattenable
static Factory NameToFactory (const char name[])
 
static const char * FactoryToName (Factory)
 
static bool NameToType (const char name[], Type *type)
 
static void Register (const char name[], Factory, Type)
 

Private Types

typedef SkFlattenable INHERITED
 

Private Member Functions

 SkPathEffect (const SkPathEffect &)
 
SkPathEffectoperator= (const SkPathEffect &)
 

Additional Inherited Members

- Protected Member Functions inherited from SkRefCntBase
void internal_dispose_restore_refcnt_to_1 () const
 Allow subclasses to call this if they've overridden internal_dispose so they can reset fRefCnt before the destructor is called or if they choose not to call the destructor (e.g. More...
 

Detailed Description

SkPathEffect is the base class for objects in the SkPaint that affect the geometry of a drawing primitive before it is transformed by the canvas' matrix and drawn.

Dashing is implemented as a subclass of SkPathEffect.

Member Enumeration Documentation

If the PathEffect can be represented as a dash pattern, asADash will return kDash_DashType and None otherwise.

If a non NULL info is passed in, the various DashInfo will be filled in if the PathEffect can be a dash pattern. If passed in info has an fCount equal or greater to that of the effect, it will memcpy the values of the dash intervals into the info. Thus the general approach will be call asADash once with default info to get DashType and fCount. If effect can be represented as a dash pattern, allocate space for the intervals in info, then call asADash again with the same info and the intervals will get copied in.

Enumerator
kNone_DashType 

ignores the info parameter

kDash_DashType 

fills in all of the info parameter

Member Function Documentation

virtual void SkPathEffect::computeFastBounds ( SkRect dst,
const SkRect src 
) const
virtual

Compute a conservative bounds for its effect, given the src bounds.

The baseline implementation just assigns src to dst.

virtual bool SkPathEffect::filterPath ( SkPath dst,
const SkPath src,
SkStrokeRec ,
const SkRect cullR 
) const
pure virtual

Given a src path (input) and a stroke-rec (input and output), apply this effect to the src path, returning the new path in dst, and return true.

If this effect cannot be applied, return false and ignore dst and stroke-rec.

The stroke-rec specifies the initial request for stroking (if any). The effect can treat this as input only, or it can choose to change the rec as well. For example, the effect can decide to change the stroke's width or join, or the effect can change the rec from stroke to fill (or fill to stroke) in addition to returning a new (dst) path.

If this method returns true, the caller will apply (as needed) the resulting stroke-rec to dst and then draw.

Implemented in SkLine2DPathEffect, SkPath1DPathEffect, SkDiscretePathEffect, SkCornerPathEffect, SkArcToPathEffect, Sk1DPathEffect, and Sk2DPathEffect.

static sk_sp<SkPathEffect> SkPathEffect::MakeCompose ( sk_sp< SkPathEffect outer,
sk_sp< SkPathEffect inner 
)
static

Returns a patheffect that applies the inner effect to the path, and then applies the outer effect to the result of the inner's.

result = outer(inner(path))

static sk_sp<SkPathEffect> SkPathEffect::MakeSum ( sk_sp< SkPathEffect first,
sk_sp< SkPathEffect second 
)
static

Returns a patheffect that apples each effect (first and second) to the original path, and returns a path with the sum of these.

result = first(path) + second(path)


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