SkPath Reference === # Path Path contains Lines and Curves which can be stroked or filled. Contour is composed of a series of connected Lines and Curves. Path may contain zero, one, or more Contours. Each Line and Curve are described by Verb, Points, and optional Conic Weight. Each pair of connected Lines and Curves share common Point; for instance, Path containing two connected Lines are described the Verb sequence: SkPath::kMove Verb, SkPath::kLine Verb, SkPath::kLine Verb; and a Point sequence with three entries, sharing the middle entry as the end of the first Line and the start of the second Line. Path components Arc, Rect, Round Rect, Circle, and Oval are composed of Lines and Curves with as many Verbs and Points required for an exact description. Once added to Path, these components may lose their identity; although Path can be inspected to determine if it describes a single Rect, Oval, Round Rect, and so on. ### Example
Path contains three Contours: Line, Circle, and Quad. Line is stroked but not filled. Circle is stroked and filled; Circle stroke forms a loop. Quad is stroked and filled, but since it is not closed, Quad does not stroke a loop.
Path contains a Fill Type which determines whether overlapping Contours form fills or holes. Fill Type also determines whether area inside or outside Lines and Curves is filled. ### Example
Path is drawn filled, then stroked, then stroked and filled.
Path contents are never shared. Copying Path by value effectively creates a new Path independent of the original. Internally, the copy does not duplicate its contents until it is edited, to reduce memory use and improve performance. ## Subtopics | topics | description | | --- | --- | ## Contour Contour contains one or more Verbs, and as many Points as are required to satisfy Verb Array. First Verb in Path is always SkPath::kMove Verb; each SkPath::kMove Verb that follows starts a new Contour. ### Example
Each SkPath::moveTo starts a new Contour, and content after SkPath::close() also starts a new Contour. Since SkPath::conicTo is not preceded by SkPath::moveTo, the first Point of the third Contour starts at the last Point of the second Contour.
If final Verb in Contour is SkPath::kClose Verb, Line connects Last Point in Contour with first Point. A closed Contour, stroked, draws Paint Stroke Join at Last Point and first Point. Without SkPath::kClose Verb as final Verb, Last Point and first Point are not connected; Contour remains open. An open Contour, stroked, draws Paint Stroke Cap at Last Point and first Point. ### Example
Path is drawn stroked, with an open Contour and a closed Contour.
## Zero Length Contour length is distance traveled from first Point to Last Point, plus, if Contour is closed, distance from Last Point to first Point. Even if Contour length is zero, stroked Lines are drawn if Paint Stroke Cap makes them visible. ### Example
# Class SkPath Paths contain geometry. Paths may be empty, or contain one or more Verbs that outline a figure. Path always starts with a move verb to a Cartesian coordinate, and may be followed by additional verbs that add lines or curves. Adding a close verb makes the geometry into a continuous loop, a closed contour. Paths may contain any number of contours, each beginning with a move verb. Path contours may contain only a move verb, or may also contain lines, Quadratic Beziers, Conics, and Cubic Beziers. Path contours may be open or closed. When used to draw a filled area, Path describes whether the fill is inside or outside the geometry. Path also describes the winding rule used to fill overlapping contours. Internally, Path lazily computes metrics likes bounds and convexity. Call SkPath::updateBoundsCache to make Path thread safe. # Overview ## Constants | constants | description | | --- | --- | | AddPathMode | Sets addPath options. | | ArcSize | Used by arcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc, Direction sweep, SkScalar x, SkScalar y). | | Convexity | Returns if Path is convex or concave. | | Direction | Sets Contour clockwise or counterclockwise. | | FillType | Sets winding rule and inverse fill. | | SegmentMask | Returns Verb types in Path. | | Verb | Controls how Path Points are interpreted. | ## Classes and Structs | class or struct | description | | --- | --- | | Iter | Iterates through lines and curves, skipping degenerates. | | RawIter | Iterates through lines and curves, including degenerates. | ## Constructors | | description | | --- | --- | | SkPath() | Constructs with default values. | | SkPath(const SkPath& path) | Makes a shallow copy. | | | Decreases Reference Count of owned objects. | ## Operators | operator | description | | --- | --- | | operator=(const SkPath& path) | Makes a shallow copy. | | operator==(const SkPath& a, const SkPath& b) | Compares paths for equality. | | operator!=(const SkPath& a, const SkPath& b) | Compares paths for inequality. | ## Member Functions | function | description | | --- | --- | | ConvertConicToQuads | Approximates Conic with Quad array. | | ConvertToNonInverseFillType | Returns Fill Type representing inside geometry. | | IsCubicDegenerate | Returns if Cubic is very small. | | IsInverseFillType | Returns if Fill Type represents outside geometry. | | IsLineDegenerate | Returns if Line is very small. | | IsQuadDegenerate | Returns if Quad is very small. | | addArc | Adds one Contour containing Arc. | | addCircle | Adds one Contour containing Circle. | | addOval | Adds one Contour containing Oval. | | addPath | Adds contents of Path. | | addPoly | Adds one Contour containing connected lines. | | addRRect | Adds one Contour containing Round Rect. | | addRect | Adds one Contour containing Rect. | | addRoundRect | Adds one Contour containing Round Rect with common corner radii. | | arcTo | Appends Arc. | | close | Makes last Contour a loop. | | computeTightBounds | Returns extent of geometry. | | conicTo | Appends Conic. | | conservativelyContainsRect | Returns true if Rect may be inside. | | contains | Returns if Point is in fill area. | | countPoints | Returns Point Array length. | | countVerbs | Returns Verb Array length. | | cubicTo | Appends Cubic. | | dump | Sends text representation using floats to standard output. | | dumpHex | Sends text representation using hexadecimal to standard output. | | getBounds | Returns maximum and minimum of Point Array. | | getConvexity | Returns geometry convexity, computing if necessary. | | getConvexityOrUnknown | Returns geometry convexity if known. | | getFillType | Returns Fill Type: winding, even-odd, inverse. | | getGenerationID | Returns unique ID. | | getLastPt | Returns Last Point. | | getPoint | Returns entry from Point Array. | | getPoints | Returns Point Array. | | getSegmentMasks | Returns types in Verb Array. | | getVerbs | Returns Verb Array. | | incReserve | Hint to reserve space for additional data. | | interpolate | Interpolates between Path pair. | | isConvex | Returns if geometry is convex. | | isEmpty | Returns if verb count is zero. | | isFinite | Returns if all Point values are finite. | | isInterpolatable | Returns if pair contains equal counts of Verb Array and Weights. | | isInverseFillType | Returns if Fill Type fills outside geometry. | | isLastContourClosed | Returns if final Contour forms a loop. | | isLine | Returns if describes Line. | | isNestedFillRects | Returns if describes Rect pair, one inside the other. | | isOval | Returns if describes Oval. | | isRRect | Returns if describes Round Rect. | | isRect | Returns if describes Rect. | | isValid | Returns if data is internally consistent. | | isVolatile | Returns if Device should not cache. | | lineTo | Appends Line. | | moveTo | Starts Contour. | | offset | Translates Point Array. | | quadTo | Appends Quad. | | rArcTo | Appends Arc relative to Last Point. | | rConicTo | Appends Conic relative to Last Point. | | rCubicTo | Appends Cubic relative to Last Point. | | rLineTo | Appends Line relative to Last Point. | | rMoveTo | Starts Contour relative to Last Point. | | rQuadTo | Appends Quad relative to Last Point. | | readFromMemory | Initializes from buffer. | | reset | Removes Verb Array, Point Array, and Weights; frees memory. | | reverseAddPath | Adds contents of Path back to front. | | rewind | Removes Verb Array, Point Array, and Weights; leaves memory allocated. | | serialize | Copies data to buffer. | | setConvexity | Sets if geometry is convex to avoid future computation. | | setFillType | Sets Fill Type: winding, even-odd, inverse. | | setIsConvex | Deprecated. | | setIsVolatile | Sets if Device should not cache. | | setLastPt | Replaces Last Point. | | swap | Exchanges Path pair. | | toggleInverseFillType | Toggles Fill Type between inside and outside geometry. | | transform | Applies Matrix to Point Array and Weights. | | unique | Returns if data has single owner. | | updateBoundsCache | Refreshes result of getBounds. | | writeToMemory | Copies data to buffer. | ## Verb ## Enum SkPath::Verb 
enum Verb {
kMove Verb, 
kLine Verb, 
kQuad Verb, 
kConic Verb, 
kCubic Verb, 
kClose Verb, 
kDone Verb, 
};
Verb instructs Path how to interpret one or more Point and optional Conic Weight; manage Contour, and terminate Path. ### Constants Each Verb has zero or more Points stored in Path. Path iterator returns complete curve descriptions, duplicating shared Points for consecutive entries.
SkPath::kMove_Verb 0Starts new Contour at next Point.
SkPath::kLine_Verb 1Adds Line from Last Point to next Point. Line is a straight segment from Point to Point.
SkPath::kQuad_Verb 2Adds Quad from Last Point, using control Point, and end Point. Quad is a parabolic section within tangents from Last Point to control Point, and control Point to end Point.
SkPath::kConic_Verb 3Adds Conic from Last Point, using control Point, end Point, and Conic Weight. Conic is a elliptical, parabolic, or hyperbolic section within tangents from Last Point to control Point, and control Point to end Point, constrained by Conic Weight. Conic Weight less than one is elliptical; equal to one is parabolic (and identical to Quad); greater than one hyperbolic.
SkPath::kCubic_Verb 4Adds Cubic from Last Point, using two control Points, and end Point. Cubic is a third-order Bezier section within tangents from Last Point to first control Point, and from second control Point to end Point.
SkPath::kClose_Verb 5Closes Contour, connecting Last Point to kMove Verb Point.
SkPath::kDone_Verb 6Terminates Path. Not in Verb Array, but returned by Path iterator.
| Verb | Allocated Points | Iterated Points | Weights | | --- | --- | --- | --- | | kMove Verb | 1 | 1 | 0 | | kLine Verb | 1 | 2 | 0 | | kQuad Verb | 2 | 3 | 0 | | kConic Verb | 2 | 3 | 1 | | kCubic Verb | 3 | 4 | 0 | | kClose Verb | 0 | 1 | 0 | | kDone Verb | -- | 0 | 0 | ### Example
#### Example Output ~~~~ verb count: 7 verbs: kMove_Verb kLine_Verb kQuad_Verb kClose_Verb kMove_Verb kCubic_Verb kConic_Verb ~~~~
## Direction ## Enum SkPath::Direction 
enum Direction {
kCW Direction, 
kCCW Direction, 
};
Direction describes whether Contour is clockwise or counterclockwise. When Path contains multiple overlapping Contours, Direction together with Fill Type determines whether overlaps are filled or form holes. Direction also determines how Contour is measured. For instance, dashing measures along Path to determine where to start and stop stroke; Direction will change dashed results as it steps clockwise or counterclockwise. Closed Contours like Rect, Round Rect, Circle, and Oval added with kCW Direction travel clockwise; the same added with kCCW Direction travel counterclockwise. ### Constants
SkPath::kCW_Direction 0Contour travels in a clockwise direction
SkPath::kCCW_Direction 1Contour travels in a counterclockwise direction
### Example
### See Also arcTo rArcTo isRect isNestedFillRects addRect addOval ## SkPath 
SkPath()
By default, Path has no Verbs, no Points, and no Weights. Fill Type is set to kWinding FillType. ### Return Value empty Path ### Example
#### Example Output ~~~~ path is empty ~~~~
### See Also reset rewind --- ## SkPath 
SkPath(const SkPath& path)
Copy constructor makes two paths identical by value. Internally, path and the returned result share pointer values. The underlying Verb Array, Point Array and Weights are copied when modified. Creating a Path copy is very efficient and never allocates memory. Paths are always copied by value from the interface; the underlying shared pointers are not exposed. ### Parameters
path Path to copy by value
### Return Value copy of Path ### Example
Modifying one path does not effect another, even if they started as copies of each other.
#### Example Output ~~~~ path verbs: 2 path2 verbs: 3 after reset path verbs: 0 path2 verbs: 3 ~~~~
### See Also operator=(const SkPath& path) --- ## ~SkPath 
~SkPath()
Releases ownership of any shared data and deletes data if Path is sole owner. ### Example
delete calls Path Destructor, but copy of original in path2 is unaffected.
### See Also SkPath() SkPath(const SkPath& path) operator=(const SkPath& path) --- ## operator= 
SkPath& operator=(const SkPath& path)
Path assignment makes two paths identical by value. Internally, assignment shares pointer values. The underlying Verb Array, Point Array and Weights are copied when modified. Copying Paths by assignment is very efficient and never allocates memory. Paths are always copied by value from the interface; the underlying shared pointers are not exposed. ### Parameters
path Verb Array, Point Array, Weights, and Fill Type to copy
### Return Value Path copied by value ### Example
#### Example Output ~~~~ path1 bounds = 10, 20, 30, 40 path2 bounds = 10, 20, 30, 40 ~~~~
### See Also swap SkPath(const SkPath& path) --- ## operator== 
bool operator==(const SkPath& a, const SkPath& b)
Compares a and b; returns true if Fill Type, Verb Array, Point Array, and Weights are equivalent. ### Parameters
a Path to compare
b Path to compare
### Return Value true if Path pair are equivalent ### Example
Rewind removes Verb Array but leaves storage; since storage is not compared, Path pair are equivalent.
#### Example Output ~~~~ empty one == two moveTo one != two rewind one == two reset one == two ~~~~
--- ## operator!= 
bool operator!=(const SkPath& a, const SkPath& b)
Compares a and b; returns true if Fill Type, Verb Array, Point Array, and Weights are not equivalent. ### Parameters
a Path to compare
b Path to compare
### Return Value true if Path pair are not equivalent ### Example
Path pair are equal though their convexity is not equal.
#### Example Output ~~~~ empty one == two addRect one == two setConvexity one == two convexity != ~~~~
--- ## isInterpolatable 
bool isInterpolatable(const SkPath& compare) const
Return true if Paths contain equal Verbs and equal Weights. If Paths contain one or more Conics, the Weights must match. conicTo may add different Verbs depending on Conic Weight, so it is not trivial to interpolate a pair of Paths containing Conics with different Conic Weight values. ### Parameters
compare Path to compare
### Return Value true if Paths Verb Array and Weights are equivalent ### Example
#### Example Output ~~~~ paths are interpolatable ~~~~
### See Also isInterpolatable --- ## interpolate 
bool interpolate(const SkPath& ending, SkScalar weight, SkPath* out) const
Interpolate between Paths with equal sized Point Arrays. Copy Verb Array and Weights to out, and set out Point Array to a weighted average of this Point Array and ending Point Array, using the formula: (this->points * weight) + ending->points * (1 - weight). weight is most useful when between zero (ending Point Array) and one (this Point Array); will work with values outside of this range. interpolate returns false and leaves out unchanged if Point Array is not the same size as ending Point Array. Call isInterpolatable to check Path compatibility prior to calling interpolate. ### Parameters
ending Point Array averaged with this Point Array
weight contribution of ending Point Array, and one minus contribution of this Point Array
out Path replaced by interpolated averages
### Return Value true if Paths contain same number of Points ### Example
### See Also isInterpolatable --- ## unique 
bool unique() const
### Return Value true if Path has one owner --- ## Fill Type ## Enum SkPath::FillType 
enum FillType {
kWinding FillType, 
kEvenOdd FillType, 
kInverseWinding FillType, 
kInverseEvenOdd FillType, 
};
Fill Type selects the rule used to fill Path. Path set to kWinding FillType fills if the sum of Contour edges is not zero, where clockwise edges add one, and counterclockwise edges subtract one. Path set to kEvenOdd FillType fills if the number of Contour edges is odd. Each Fill Type has an inverse variant that reverses the rule: kInverseWinding FillType fills where the sum of Contour edges is zero; kInverseEvenOdd FillType fills where the number of Contour edges is even. ### Example
The top row has two clockwise rectangles. The second row has one clockwise and one counterclockwise rectangle. The even-odd variants draw the same. The winding variants draw the top rectangle overlap, which has a winding of 2, the same as the outer parts of the top rectangles, which have a winding of 1.
### Constants
SkPath::kWinding_FillType 0Specifies fill as area is enclosed by a non-zero sum of Contour Directions.
SkPath::kEvenOdd_FillType 1Specifies fill as area enclosed by an odd number of Contours.
SkPath::kInverseWinding_FillType 2Specifies fill as area is enclosed by a zero sum of Contour Directions.
SkPath::kInverseEvenOdd_FillType 3Specifies fill as area enclosed by an even number of Contours.
### Example
### See Also SkPaint::Style Direction getFillType setFillType ## getFillType 
FillType getFillType() const
Returns FillType, the rule used to fill Path. FillType of a new Path is kWinding FillType. ### Return Value one of: kWinding FillType, kEvenOdd FillType, kInverseWinding FillType, kInverseEvenOdd FillType ### Example
#### Example Output ~~~~ default path fill type is kWinding_FillType ~~~~
### See Also FillType setFillType isInverseFillType --- ## setFillType 
void setFillType(FillType ft)
Sets FillType, the rule used to fill Path. While there is no check that ft is legal, values outside of FillType are not supported. ### Parameters
ft one of: kWinding FillType, kEvenOdd FillType, kInverseWinding FillType, kInverseEvenOdd FillType
### Example
If empty Path is set to inverse FillType, it fills all pixels.
### See Also FillType getFillType toggleInverseFillType --- ## isInverseFillType 
bool isInverseFillType() const
Returns if FillType describes area outside Path geometry. The inverse fill area extends indefinitely. ### Return Value true if FillType is kInverseWinding FillType or kInverseEvenOdd FillType ### Example
#### Example Output ~~~~ default path fill type is inverse: false ~~~~
### See Also FillType getFillType setFillType toggleInverseFillType --- ## toggleInverseFillType 
void toggleInverseFillType()
Replace FillType with its inverse. The inverse of FillType describes the area unmodified by the original FillType. | FillType | toggled FillType | | --- | --- | | kWinding FillType | kInverseWinding FillType | | kEvenOdd FillType | kInverseEvenOdd FillType | | kInverseWinding FillType | kWinding FillType | | kInverseEvenOdd FillType | kEvenOdd FillType | ### Example
Path drawn normally and through its inverse touches every pixel once.
### See Also FillType getFillType setFillType isInverseFillType --- ## Convexity ## Enum SkPath::Convexity 
enum Convexity : uint8_t {
kUnknown Convexity, 
kConvex Convexity,
kConcave Convexity, 
};
Path is convex if it contains one Contour and Contour loops no more than 360 degrees, and Contour angles all have same Direction. Convex Path may have better performance and require fewer resources on GPU Surface. Path is concave when either at least one Direction change is clockwise and another is counterclockwise, or the sum of the changes in Direction is not 360 degrees. Initially Path Convexity is kUnknown Convexity. Path Convexity is computed if needed by destination Surface. ### Constants
SkPath::kUnknown_Convexity 0Indicates Convexity has not been determined.
SkPath::kConvex_Convexity 1Path has one Contour made of a simple geometry without indentations.
SkPath::kConcave_Convexity 2Path has more than one Contour, or a geometry with indentations.
### Example
### See Also Contour Direction getConvexity getConvexityOrUnknown setConvexity isConvex ## getConvexity 
Convexity getConvexity() const
Computes Convexity if required, and returns stored value. Convexity is computed if stored value is kUnknown Convexity, or if Path has been altered since Convexity was computed or set. ### Return Value computed or stored Convexity ### Example
### See Also Convexity Contour Direction getConvexityOrUnknown setConvexity isConvex --- ## getConvexityOrUnknown 
Convexity getConvexityOrUnknown() const
Returns last computed Convexity, or kUnknown Convexity if Path has been altered since Convexity was computed or set. ### Return Value stored Convexity ### Example
Convexity is unknown unless getConvexity is called without a subsequent call that alters the path.
### See Also Convexity Contour Direction getConvexity setConvexity isConvex --- ## setConvexity 
void setConvexity(Convexity convexity)
Stores convexity so that it is later returned by getConvexity or getConvexityOrUnknown. convexity may differ from getConvexity, although setting an incorrect value may cause incorrect or inefficient drawing. If convexity is kUnknown Convexity: getConvexity will compute Convexity, and getConvexityOrUnknown will return kUnknown Convexity. If convexity is kConvex Convexity or kConcave Convexity, getConvexity and getConvexityOrUnknown will return convexity until the path is altered. ### Parameters
convexity one of: kUnknown Convexity, kConvex Convexity, or kConcave Convexity
### Example
### See Also Convexity Contour Direction getConvexity getConvexityOrUnknown isConvex --- ## isConvex 
bool isConvex() const
Computes Convexity if required, and returns true if value is kConvex Convexity. If setConvexity was called with kConvex Convexity or kConcave Convexity, and the path has not been altered, Convexity is not recomputed. ### Return Value true if Convexity stored or computed is kConvex Convexity ### Example
Concave shape is erroneously considered convex after a forced call to setConvexity.
### See Also Convexity Contour Direction getConvexity getConvexityOrUnknown setConvexity --- ## setIsConvex 
void setIsConvex(bool isConvex)
Deprecated. Use setConvexity. ### See Also Convexity setConvexity getConvexity --- ## isOval 
bool isOval(SkRect* rect, Direction* dir = nullptr, unsigned* start = nullptr) const
Returns true if constructed by addCircle, addOval; and in some cases, addRoundRect, addRRect. Path constructed with conicTo or rConicTo will not return true though Path draws Oval. rect receives bounds of Oval. dir receives Direction of Oval: kCW Direction if clockwise, kCCW Direction if counterclockwise. start receives start of Oval: 0 for top, 1 for right, 2 for bottom, 3 for left. rect, dir, and start are unmodified if Oval is not found. Triggers performance optimizations on some GPU Surface implementations. ### Parameters
rect storage for bounding Rect of Oval; may be nullptr
dir storage for Direction; may be nullptr
start storage for start of Oval; may be nullptr
### Return Value true if Path was constructed by method that reduces to Oval ### Example
### See Also Oval addCircle addOval --- ## isRRect 
bool isRRect(SkRRect* rrect, Direction* dir = nullptr, unsigned* start = nullptr) const
Returns true if constructed by addRoundRect, addRRect; and if construction is not empty, not Rect, and not Oval. Path constructed with other calls will not return true though Path draws Round Rect. rrect receives bounds of Round Rect. dir receives Direction of Oval: kCW Direction if clockwise, kCCW Direction if counterclockwise. start receives start of Round Rect: 0 for top, 1 for right, 2 for bottom, 3 for left. rrect, dir, and start are unmodified if Round Rect is not found. Triggers performance optimizations on some GPU Surface implementations. ### Parameters
rrect storage for bounding Rect of Round Rect; may be nullptr
dir storage for Direction; may be nullptr
start storage for start of Round Rect; may be nullptr
### Return Value true if Path contains only Round Rect ### Example
Draw rounded rectangle and its bounds. Draw an arc indicating where the rounded rectangle starts and its direction.
### See Also Round Rect addRoundRect addRRect --- ## reset 
void reset()
Sets Path to its initial state. Removes Verb Array, Point Array, and Weights, and sets FillType to kWinding FillType. Internal storage associated with Path is released. ### Example
### See Also rewind --- ## rewind 
void rewind()
Sets Path to its initial state, preserving internal storage. Removes Verb Array, Point Array, and Weights, and sets FillType to kWinding FillType. Internal storage associated with Path is retained. Use rewind instead of reset if Path storage will be reused and performance is critical. ### Example
Although path1 retains its internal storage, it is indistinguishable from a newly initialized path.
### See Also reset --- ## isEmpty 
bool isEmpty() const
Empty Path may have FillType but has no SkPoint, Verb, or Conic Weight. SkPath() constructs empty Path; reset and (rewind) make Path empty. ### Return Value true if the path contains no Verb array ### Example
#### Example Output ~~~~ initial path is empty after moveTo path is not empty after rewind path is empty after lineTo path is not empty after reset path is empty ~~~~
### See Also SkPath() reset rewind --- ## isLastContourClosed 
bool isLastContourClosed() const
Contour is closed if Path Verb array was last modified by close. When stroked, closed Contour draws Paint Stroke Join instead of Paint Stroke Cap at first and last Point. ### Return Value true if the last Contour ends with a kClose Verb ### Example
close has no effect if Path is empty; isLastContourClosed returns false until Path has geometry followed by close.
#### Example Output ~~~~ initial last contour is not closed after close last contour is not closed after lineTo last contour is not closed after close last contour is closed ~~~~
### See Also close --- ## isFinite 
bool isFinite() const
Returns true for finite Point array values between negative SK ScalarMax and positive SK ScalarMax. Returns false for any Point array value of SK ScalarInfinity, SK ScalarNegativeInfinity, or SK ScalarNaN. ### Return Value true if all Point values are finite ### Example
#### Example Output ~~~~ initial path is finite after line path is finite after scale path is not finite ~~~~
### See Also SkScalar --- ## isVolatile 
bool isVolatile() const
Returns true if the path is volatile; it will not be altered or discarded by the caller after it is drawn. Paths by default have volatile set false, allowing Surface to attach a cache of data which speeds repeated drawing. If true, Surface may not speed repeated drawing. ### Return Value true if caller will alter Path after drawing ### Example
#### Example Output ~~~~ volatile by default is false ~~~~
### See Also setIsVolatile --- ## setIsVolatile 
void setIsVolatile(bool isVolatile)
Specify whether Path is volatile; whether it will be altered or discarded by the caller after it is drawn. Paths by default have volatile set false, allowing Device to attach a cache of data which speeds repeated drawing. Mark temporary paths, discarded or modified after use, as volatile to inform Device that the path need not be cached. Mark animating Path volatile to improve performance. Mark unchanging Path non-volatile to improve repeated rendering. Raster Surface Path draws are affected by volatile for some shadows. GPU Surface Path draws are affected by volatile for some shadows and concave geometries. ### Parameters
isVolatile true if caller will alter Path after drawing
### Example
### See Also isVolatile --- ## IsLineDegenerate 
static bool IsLineDegenerate(const SkPoint& p1, const SkPoint& p2, bool exact)
Test if Line between Point pair is degenerate. Line with no length or that moves a very short distance is degenerate; it is treated as a point. exact changes the equality test. If true, returns true only if p1 equals p2. If false, returns true if p1 equals or nearly equals p2. ### Parameters
p1 line start point
p2 line end point
exact if false, allow nearly equals
### Return Value true if Line is degenerate; its length is effectively zero ### Example
As single precision floats, 100 and 100.000001 have the same bit representation, and are exactly equal. 100 and 100.0001 have different bit representations, and are not exactly equal, but are nearly equal.
#### Example Output ~~~~ line from (100,100) to (100,100) is degenerate, nearly line from (100,100) to (100,100) is degenerate, exactly line from (100,100) to (100.0001,100.0001) is degenerate, nearly line from (100,100) to (100.0001,100.0001) is not degenerate, exactly ~~~~
### See Also IsQuadDegenerate IsCubicDegenerate SkPoint::equalsWithinTolerance --- ## IsQuadDegenerate 
static bool IsQuadDegenerate(const SkPoint& p1, const SkPoint& p2,
                             const SkPoint& p3, bool exact)
Test if Quad is degenerate. Quad with no length or that moves a very short distance is degenerate; it is treated as a point. ### Parameters
p1 Quad start point
p2 Quad control point
p3 Quad end point
exact if true, returns true only if p1, p2, and p3 are equal; if false, returns true if p1, p2, and p3 are equal or nearly equal
### Return Value true if Quad is degenerate; its length is effectively zero ### Example
As single precision floats: 100, 100.00001, and 100.00002 have different bit representations but nearly the same value. Translating all three by 1000 gives them the same bit representation; the fractional portion of the number can not be represented by the float and is lost.
#### Example Output ~~~~ quad (100,100), (100.00001,100.00001), (100.00002,100.00002) is degenerate, nearly quad (1100,1100), (1100,1100), (1100,1100) is degenerate, nearly quad (100,100), (100.00001,100.00001), (100.00002,100.00002) is not degenerate, exactly quad (1100,1100), (1100,1100), (1100,1100) is degenerate, exactly ~~~~
### See Also IsLineDegenerate IsCubicDegenerate SkPoint::equalsWithinTolerance --- ## IsCubicDegenerate 
static bool IsCubicDegenerate(const SkPoint& p1, const SkPoint& p2,
                              const SkPoint& p3, const SkPoint& p4, bool exact)
Test if Cubic is degenerate. Cubic with no length or that moves a very short distance is degenerate; it is treated as a point. ### Parameters
p1 Cubic start point
p2 Cubic control point 1
p3 Cubic control point 2
p4 Cubic end point
exact if true, returns true only if p1, p2, p3, and p4 are equal; if false, returns true if p1, p2, p3, and p4 are equal or nearly equal
### Return Value true if Cubic is degenerate; its length is effectively zero ### Example
#### Example Output ~~~~ 0.00024414062 is degenerate 0.00024414065 is length ~~~~
--- ## isLine 
bool isLine(SkPoint line[2]) const
Returns true if Path contains only one Line; Path Verb array has two entries: kMove Verb, kLine Verb. If Path contains one Line and line is not nullptr, line is set to Line start point and Line end point. Returns false if Path is not one Line; line is unaltered. ### Parameters
line storage for Line. May be nullptr
### Return Value true if Path contains exactly one Line ### Example
#### Example Output ~~~~ empty is not line zero line is line (0,0) (0,0) line is line (10,10) (20,20) second move is not line ~~~~
--- ## Point Array Point Array contains Points satisfying the allocated Points for each Verb in Verb Array. For instance, Path containing one Contour with Line and Quad is described by Verb Array: Verb::kMoveTo, Verb::kLineTo, Verb::kQuadTo; and one Point for move, one Point for Line, two Points for Quad; totaling four Points. Point Array may be read directly from Path with getPoints, or inspected with getPoint, with Iter, or with RawIter. ## getPoints 
int getPoints(SkPoint points[], int max) const
Returns number of points in Path. Up to max points are copied. points may be nullptr; then, max must be zero. If max is greater than number of points, excess points storage is unaltered. ### Parameters
points storage for Path Point array. May be nullptr
max maximum to copy; must be greater than or equal to zero
### Return Value Path Point array length ### Example
#### Example Output ~~~~ no points point count: 3 zero max point count: 3 too small point count: 3 (0,0) (20,20) just right point count: 3 (0,0) (20,20) (-10,-10) ~~~~
### See Also countPoints getPoint --- ## countPoints 
int countPoints() const
Returns the number of points in Path. Point count is initially zero. ### Return Value Path Point array length ### Example
#### Example Output ~~~~ empty point count: 0 zero line point count: 2 line point count: 2 second move point count: 3 ~~~~
### See Also getPoints --- ## getPoint 
SkPoint getPoint(int index) const
Returns Point at index in Point Array. Valid range for index is 0 to countPoints - 1. Returns (0, 0) if index is out of range. ### Parameters
index Point array element selector
### Return Value Point array value or (0, 0) ### Example
#### Example Output ~~~~ point 0: (-10,-10) point 1: (10,10) ~~~~
### See Also countPoints getPoints --- ## Verb Array Verb Array always starts with kMove Verb. If kClose Verb is not the last entry, it is always followed by kMove Verb; the quantity of kMove Verb equals the Contour count. Verb Array does not include or count kDone Verb; it is a convenience returned when iterating through Verb Array. Verb Array may be read directly from Path with getVerbs, or inspected with Iter, or with RawIter. ## countVerbs 
int countVerbs() const
Returns the number of Verbs: kMove Verb, kLine Verb, kQuad Verb, kConic Verb, kCubic Verb, and kClose Verb; added to Path. ### Return Value length of Verb Array ### Example
#### Example Output ~~~~ empty verb count: 0 round rect verb count: 10 ~~~~
### See Also getVerbs Iter RawIter --- ## getVerbs 
int getVerbs(uint8_t verbs[], int max) const
Returns the number of verbs in the path. Up to max verbs are copied. The verbs are copied as one byte per verb. ### Parameters
verbs storage for verbs, may be nullptr
max maximum number to copy into verbs
### Return Value the actual number of verbs in the path ### Example
#### Example Output ~~~~ no verbs verb count: 3 zero max verb count: 3 too small verb count: 3 move line just right verb count: 3 move line line ~~~~
### See Also countVerbs getPoints Iter RawIter --- ## swap 
void swap(SkPath& other)
Exchanges the Verb Array, Point Array, Weights, and Fill Type with other. Cached state is also exchanged. swap internally exchanges pointers, so it is lightweight and does not allocate memory. swap usage has largely been replaced by operator=(const SkPath& path). Paths do not copy their content on assignment until they are written to, making assignment as efficient as swap. ### Parameters
other Path exchanged by value
### Example
#### Example Output ~~~~ path1 bounds = 0, 0, 0, 0 path2 bounds = 10, 20, 30, 40 ~~~~
### See Also operator=(const SkPath& path) --- ## getBounds 
const SkRect& getBounds() const
Returns minimum and maximum x and y values of Point Array. Returns (0, 0, 0, 0) if Path contains no points. Returned bounds width and height may be larger or smaller than area affected when Path is drawn. Rect returned includes all Points added to Path, including Points associated with kMove Verb that define empty Contours. ### Return Value bounds of all Points in Point Array ### Example
Bounds of upright Circle can be predicted from center and radius. Bounds of rotated Circle includes control Points outside of filled area.
#### Example Output ~~~~ empty bounds = 0, 0, 0, 0 circle bounds = 25, 20, 75, 70 rotated circle bounds = 14.6447, 9.64466, 85.3553, 80.3553 ~~~~
### See Also computeTightBounds updateBoundsCache --- ## updateBoundsCache 
void updateBoundsCache() const
Update internal bounds so that subsequent calls to getBounds are instantaneous. Unaltered copies of Path may also access cached bounds through getBounds. For now, identical to calling getBounds and ignoring the returned value. Call to prepare Path subsequently drawn from multiple threads, to avoid a race condition where each draw separately computes the bounds. ### Example
#### Example Output ~~~~ #Volatile uncached avg: 0.18048 ms cached avg: 0.182784 ms ~~~~
### See Also getBounds --- ## computeTightBounds 
SkRect computeTightBounds() const
Returns minimum and maximum x and y values of the lines and curves in Path. Returns (0, 0, 0, 0) if Path contains no points. Returned bounds width and height may be larger or smaller than area affected when Path is drawn. Includes Points associated with kMove Verb that define empty Contours. Behaves identically to getBounds when Path contains only lines. If Path contains curves, computed bounds includes the maximum extent of the Quad, Conic, or Cubic; is slower than getBounds; and unlike getBounds, does not cache the result. ### Return Value tight bounds of curves in Path ### Example
#### Example Output ~~~~ empty bounds = 0, 0, 0, 0 circle bounds = 25, 20, 75, 70 rotated circle bounds = 25, 20, 75, 70 ~~~~
### See Also getBounds --- ## conservativelyContainsRect 
bool conservativelyContainsRect(const SkRect& rect) const
Returns true if rect is contained by Path. May return false when rect is contained by Path. For now, only returns true if Path has one Contour and is convex. rect may share points and edges with Path and be contained. Returns true if rect is empty, that is, it has zero width or height; and the Point or Line described by rect is contained by Path. ### Parameters
rect Rect, Line, or Point checked for containment
### Return Value true if rect is contained ### Example
Rect is drawn in blue if it is contained by red Path.
### See Also contains Op Rect Convexity --- ## incReserve 
void incReserve(unsigned extraPtCount)
grows Path Verb Array and Point Array to contain extraPtCount additional Points. May improve performance and use less memory by reducing the number and size of allocations when creating Path. ### Parameters
extraPtCount number of additional Points to allocate
### Example
### See Also Point Array --- ## moveTo 
void moveTo(SkScalar x, SkScalar y)
Adds beginning of Contour at Point (x, y). ### Parameters
x x-coordinate of Contour start
y y-coordinate of Contour start
### Example
### See Also Contour lineTo rMoveTo quadTo conicTo cubicTo close --- 
void moveTo(const SkPoint& p)
Adds beginning of Contour at Point p. ### Parameters
p contour start
### Example
### See Also Contour lineTo rMoveTo quadTo conicTo cubicTo close --- ## rMoveTo 
void rMoveTo(SkScalar dx, SkScalar dy)
Adds beginning of Contour relative to Last Point. If Path is empty, starts Contour at (dx, dy). Otherwise, start Contour at Last Point offset by (dx, dy). Function name stands for "relative move to". ### Parameters
dx offset from Last Point x to Contour start x
dy offset from Last Point y to Contour start y
### Example
### See Also Contour lineTo moveTo quadTo conicTo cubicTo close --- ## lineTo 
void lineTo(SkScalar x, SkScalar y)
Adds Line from Last Point to (x, y). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Line. lineTo appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed. lineTo then appends kLine Verb to Verb Array and (x, y) to Point Array. ### Parameters
x end of added Line in x
y end of added Line in y
### Example
### See Also Contour moveTo rLineTo addRect --- 
void lineTo(const SkPoint& p)
Adds Line from Last Point to Point p. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Line. lineTo first appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed. lineTo then appends kLine Verb to Verb Array and Point p to Point Array. ### Parameters
p end Point of added Line
### Example
### See Also Contour moveTo rLineTo addRect --- ## rLineTo 
void rLineTo(SkScalar dx, SkScalar dy)
Adds Line from Last Point to Vector (dx, dy). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Line. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kLine Verb to Verb Array and Line end to Point Array. Line end is Last Point plus Vector (dx, dy). Function name stands for "relative line to". ### Parameters
dx offset from Last Point x to Line end x
dy offset from Last Point y to Line end y
### Example
### See Also Contour moveTo lineTo addRect --- # Quad Quad describes a quadratic Bezier, a second-order curve identical to a section of a parabola. Quad begins at a start Point, curves towards a control Point, and then curves to an end Point. ### Example
Quad is a special case of Conic where Conic Weight is set to one. Quad is always contained by the triangle connecting its three Points. Quad begins tangent to the line between start Point and control Point, and ends tangent to the line between control Point and end Point. ### Example
## quadTo 
void quadTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2)
Adds Quad from Last Point towards (x1, y1), to (x2, y2). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Quad. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kQuad Verb to Verb Array; and (x1, y1), (x2, y2) to Point Array. ### Parameters
x1 control Point of Quad in x
y1 control Point of Quad in y
x2 end Point of Quad in x
y2 end Point of Quad in y
### Example
### See Also Contour moveTo conicTo rQuadTo --- 
void quadTo(const SkPoint& p1, const SkPoint& p2)
Adds Quad from Last Point towards Point p1, to Point p2. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Quad. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kQuad Verb to Verb Array; and Points p1, p2 to Point Array. ### Parameters
p1 control Point of added Quad
p2 end Point of added Quad
### Example
### See Also Contour moveTo conicTo rQuadTo --- ## rQuadTo 
void rQuadTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2)
Adds Quad from Last Point towards Vector (dx1, dy1), to Vector (dx2, dy2). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Quad. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kQuad Verb to Verb Array; and appends Quad control and Quad end to Point Array. Quad control is Last Point plus Vector (dx1, dy1). Quad end is Last Point plus Vector (dx2, dy2). Function name stands for "relative quad to". ### Parameters
dx1 offset from Last Point x to Quad control x
dy1 offset from Last Point x to Quad control y
dx2 offset from Last Point x to Quad end x
dy2 offset from Last Point x to Quad end y
### Example
### See Also Contour moveTo conicTo quadTo --- # Conic Conic describes a conical section: a piece of an ellipse, or a piece of a parabola, or a piece of a hyperbola. Conic begins at a start Point, curves towards a control Point, and then curves to an end Point. The influence of the control Point is determined by Conic Weight. Each Conic in Path adds two Points and one Conic Weight. Conic Weights in Path may be inspected with Iter, or with RawIter. ## Weight Weight determines both the strength of the control Point and the type of Conic. If Weight is exactly one, then Conic is identical to Quad; it is always a parabolic segment. ### Example
When Conic Weight is one, Quad is added to path; the two are identical.
#### Example Output ~~~~ move {0, 0}, quad {0, 0}, {20, 30}, {50, 60}, done ~~~~
If weight is less than one, Conic is an elliptical segment. ### Example
A 90 degree circular arc has the weight1 / sqrt(2).
#### Example Output ~~~~ move {0, 0}, conic {0, 0}, {20, 0}, {20, 20}, weight = 0.707107 done ~~~~
If weight is greater than one, Conic is a hyperbolic segment. As weight gets large, a hyperbolic segment can be approximated by straight lines connecting the control Point with the end Points. ### Example
#### Example Output ~~~~ move {0, 0}, line {0, 0}, {20, 0}, line {20, 0}, {20, 20}, done ~~~~
## conicTo 
void conicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar w)
Adds Conic from Last Point towards (x1, y1), to (x2, y2), weighted by w. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Conic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed. If w is finite and not one, appends kConic Verb to Verb Array; and (x1, y1), (x2, y2) to Point Array; and w to Conic Weights. If w is one, appends kQuad Verb to Verb Array, and (x1, y1), (x2, y2) to Point Array. If w is not finite, appends kLine Verb twice to Verb Array, and (x1, y1), (x2, y2) to Point Array. ### Parameters
x1 control Point of Conic in x
y1 control Point of Conic in y
x2 end Point of Conic in x
y2 end Point of Conic in y
w weight of added Conic
### Example
As weight increases, curve is pulled towards control point. The bottom two curves are elliptical; the next is parabolic; the top curve is hyperbolic.
### See Also rConicTo arcTo addArc quadTo --- 
void conicTo(const SkPoint& p1, const SkPoint& p2, SkScalar w)
Adds Conic from Last Point towards Point p1, to Point p2, weighted by w. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Conic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed. If w is finite and not one, appends kConic Verb to Verb Array; and Points p1, p2 to Point Array; and w to Conic Weights. If w is one, appends kQuad Verb to Verb Array, and Points p1, p2 to Point Array. If w is not finite, appends kLine Verb twice to Verb Array, and Points p1, p2 to Point Array. ### Parameters
p1 control Point of added Conic
p2 end Point of added Conic
w weight of added Conic
### Example
Conics and arcs use identical representations. As the arc sweep increases the Conic Weight also increases, but remains smaller than one.
### See Also rConicTo arcTo addArc quadTo --- ## rConicTo 
void rConicTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2, SkScalar w)
Adds Conic from Last Point towards Vector (dx1, dy1), to Vector (dx2, dy2), weighted by w. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Conic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed. If w is finite and not one, next appends kConic Verb to Verb Array, and w is recorded as Conic Weight; otherwise, if w is one, appends kQuad Verb to Verb Array; or if w is not finite, appends kLine Verb twice to Verb Array. In all cases appends Points control and end to Point Array. control is Last Point plus Vector (dx1, dy1). end is Last Point plus Vector (dx2, dy2). Function name stands for "relative conic to". ### Parameters
dx1 offset from Last Point x to Conic control x
dy1 offset from Last Point x to Conic control y
dx2 offset from Last Point x to Conic end x
dy2 offset from Last Point x to Conic end y
w weight of added Conic
### Example
### See Also conicTo arcTo addArc quadTo --- # Cubic Cubic describes a Bezier curve segment described by a third-order polynomial. Cubic begins at a start Point, curving towards the first control Point; and curves from the end Point towards the second control Point. ### Example
## cubicTo 
void cubicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar x3,
             SkScalar y3)
Adds Cubic from Last Point towards (x1, y1), then towards (x2, y2), ending at (x3, y3). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Cubic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kCubic Verb to Verb Array; and (x1, y1), (x2, y2), (x3, y3) to Point Array. ### Parameters
x1 first control Point of Cubic in x
y1 first control Point of Cubic in y
x2 second control Point of Cubic in x
y2 second control Point of Cubic in y
x3 end Point of Cubic in x
y3 end Point of Cubic in y
### Example
### See Also Contour moveTo rCubicTo quadTo --- 
void cubicTo(const SkPoint& p1, const SkPoint& p2, const SkPoint& p3)
Adds Cubic from Last Point towards Point p1, then towards Point p2, ending at Point p3. If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Cubic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kCubic Verb to Verb Array; and Points p1, p2, p3 to Point Array. ### Parameters
p1 first control Point of Cubic
p2 second control Point of Cubic
p3 end Point of Cubic
### Example
### See Also Contour moveTo rCubicTo quadTo --- ## rCubicTo 
void rCubicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar x3,
              SkScalar y3)
Adds Cubic from Last Point towards Vector (dx1, dy1), then towards Vector (dx2, dy2), to Vector (dx3, dy3). If Path is empty, or last Verb is kClose Verb, Last Point is set to (0, 0) before adding Cubic. Appends kMove Verb to Verb Array and (0, 0) to Point Array, if needed; then appends kCubic Verb to Verb Array; and appends Cubic control and Cubic end to Point Array. Cubic control is Last Point plus Vector (dx1, dy1). Cubic end is Last Point plus Vector (dx2, dy2). Function name stands for "relative cubic to". ### Parameters
x1 offset from Last Point x to first Cubic control x
y1 offset from Last Point x to first Cubic control y
x2 offset from Last Point x to second Cubic control x
y2 offset from Last Point x to second Cubic control y
x3 offset from Last Point x to Cubic end x
y3 offset from Last Point x to Cubic end y
### Example
### See Also Contour moveTo cubicTo quadTo --- # Arc Arc can be constructed in a number of ways. Arc may be described by part of Oval and angles, by start point and end point, and by radius and tangent lines. Each construction has advantages, and some constructions correspond to Arc drawing in graphics standards. All Arc draws are implemented by one or more Conic draws. When Conic Weight is less than one, Conic describes an Arc of some Oval or Circle. arcTo(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle, bool forceMoveTo) describes Arc as a piece of Oval, beginning at start angle, sweeping clockwise or counterclockwise, which may continue Contour or start a new one. This construction is similar to PostScript and HTML Canvas arcs. Variation addArc always starts new Contour. Canvas::drawArc draws without requiring Path. arcTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar radius) describes Arc as tangent to the line (x0, y0), (x1, y1) and tangent to the line (x1, y1), (x2, y2) where (x0, y0) is the last Point added to Path. This construction is similar to PostScript and HTML Canvas arcs. arcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc, Direction sweep, SkScalar x, SkScalar y) describes Arc as part of Oval with radii (rx, ry), beginning at last Point added to Path and ending at (x, y). More than one Arc satisfies this criteria, so additional values choose a single solution. This construction is similar to SVG arcs. conicTo describes Arc of less than 180 degrees as a pair of tangent lines and Conic Weight. conicTo can represent any Arc with a sweep less than 180 degrees at any rotation. All arcTo constructions are converted to Conic data when added to Path. ### Example
1 arcTo(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle, bool forceMoveTo)
2 parameter sets force MoveTo
3 start angle must be multiple of 90 degrees.
4 arcTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar radius)
5 arcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc, Direction sweep, SkScalar x, SkScalar y)
### Example
1 describes an arc from an oval, a starting angle, and a sweep angle. 2 is similar to 1, but does not require building a path to draw. 3 is similar to 1, but always begins new Contour. 4 describes an arc from a pair of tangent lines and a radius. 5 describes an arc from Oval center, arc start Point and arc end Point. 6 describes an arc from a pair of tangent lines and a Conic Weight.
## arcTo 
void arcTo(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle,
           bool forceMoveTo)
Append Arc to Path. Arc added is part of ellipse bounded by oval, from startAngle through sweepAngle. Both startAngle and sweepAngle are measured in degrees, where zero degrees is aligned with the positive x-axis, and positive sweeps extends Arc clockwise. arcTo adds Line connecting Path last Point to initial Arc Point if forceMoveTo is false and Path is not empty. Otherwise, added Contour begins with first point of Arc. Angles greater than -360 and less than 360 are treated modulo 360. ### Parameters
oval bounds of ellipse containing Arc
startAngle starting angle of Arc in degrees
sweepAngle sweep, in degrees. Positive is clockwise; treated modulo 360
forceMoveTo true to start a new contour with Arc
### Example
arcTo continues a previous contour when forceMoveTo is false and when Path is not empty.
### See Also addArc SkCanvas::drawArc conicTo --- 
void arcTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar radius)
Append Arc to Path, after appending Line if needed. Arc is implemented by Conic weighted to describe part of Circle. Arc is contained by tangent from last Path point (x0, y0) to (x1, y1), and tangent from (x1, y1) to (x2, y2). Arc is part of Circle sized to radius, positioned so it touches both tangent lines. ### Example
If last Path Point does not start Arc, arcTo appends connecting Line to Path. The length of Vector from (x1, y1) to (x2, y2) does not affect Arc. ### Example
Arc sweep is always less than 180 degrees. If radius is zero, or if tangents are nearly parallel, arcTo appends Line from last Path Point to (x1, y1). arcTo appends at most one Line and one Conic. arcTo implements the functionality of PostScript Arct and HTML Canvas ArcTo. ### Parameters
x1 x common to pair of tangents
y1 y common to pair of tangents
x2 x end of second tangent
y2 y end of second tangent
radius distance from Arc to Circle center
### Example
arcTo is represented by Line and circular Conic in Path.
#### Example Output ~~~~ move to (156,20) line (156,20),(79.2893,20) conic (79.2893,20),(200,20),(114.645,105.355) weight 0.382683 ~~~~
### See Also conicTo --- 
void arcTo(const SkPoint p1, const SkPoint p2, SkScalar radius)
Append Arc to Path, after appending Line if needed. Arc is implemented by Conic weighted to describe part of Circle. Arc is contained by tangent from last Path point to p1, and tangent from p1 to p2. Arc is part of Circle sized to radius, positioned so it touches both tangent lines. If last Path Point does not start Arc, arcTo appends connecting Line to Path. The length of Vector from p1 to p2 does not affect Arc. Arc sweep is always less than 180 degrees. If radius is zero, or if tangents are nearly parallel, arcTo appends Line from last Path Point to p1. arcTo appends at most one Line and one Conic. arcTo implements the functionality of PostScript Arct and HTML Canvas ArcTo. ### Parameters
p1 Point common to pair of tangents
p2 end of second tangent
radius distance from Arc to Circle center
### Example
Because tangent lines are parallel, arcTo appends line from last Path Point to p1, but does not append a circular Conic.
#### Example Output ~~~~ move to (156,20) line (156,20),(200,20) ~~~~
### See Also conicTo --- ## Enum SkPath::ArcSize 
enum ArcSize {
kSmall ArcSize, 
kLarge ArcSize, 
};
Four Oval parts with radii (rx, ry) start at last Path Point and ends at (x, y). ArcSize and Direction select one of the four Oval parts. ### Constants
SkPath::kSmall_ArcSize 0smaller of Arc pair
SkPath::kLarge_ArcSize 1larger of Arc pair
### Example
Arc begins at top of Oval pair and ends at bottom. Arc can take four routes to get there. Two routes are large, and two routes are counterclockwise. The one route both large and counterclockwise is blue.
### See Also arcTo Direction 
void arcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc,
           Direction sweep, SkScalar x, SkScalar y)
Append Arc to Path. Arc is implemented by one or more Conics weighted to describe part of Oval with radii (rx, ry) rotated by xAxisRotate degrees. Arc curves from last Path Point to (x, y), choosing one of four possible routes: clockwise or counterclockwise, and smaller or larger. Arc sweep is always less than 360 degrees. arcTo appends Line to (x, y) if either radii are zero, or if last Path Point equals (x, y). arcTo scales radii (rx, ry) to fit last Path Point and (x, y) if both are greater than zero but too small. arcTo appends up to four Conic curves. arcTo implements the functionality of SVG Arc, although SVG "" value is opposite the integer value of sweep; SVG "" uses 1 for clockwise, while kCW Direction cast to int is zero. ### Parameters
rx radius in x before x-axis rotation
ry radius in y before x-axis rotation
xAxisRotate x-axis rotation in degrees; positive values are clockwise
largeArc chooses smaller or larger Arc
sweep chooses clockwise or counterclockwise Arc
x end of Arc
y end of Arc
### Example
### See Also rArcTo ArcSize Direction --- 
void arcTo(const SkPoint r, SkScalar xAxisRotate, ArcSize largeArc,
           Direction sweep, const SkPoint xy)
Append Arc to Path. Arc is implemented by one or more Conic weighted to describe part of Oval with radii (r.fX, r.fY) rotated by xAxisRotate degrees. Arc curves from last Path Point to (xy.fX, xy.fY), choosing one of four possible routes: clockwise or counterclockwise, and smaller or larger. Arc sweep is always less than 360 degrees. arcTo appends Line to xy if either radii are zero, or if last Path Point equals (x, y). arcTo scales radii r to fit last Path Point and xy if both are greater than zero but too small to describe an arc. arcTo appends up to four Conic curves. arcTo implements the functionality of SVG Arc, although SVG "" value is opposite the integer value of sweep; SVG "" uses 1 for clockwise, while kCW Direction cast to int is zero. ### Parameters
r radii in x and y before x-axis rotation
xAxisRotate x-axis rotation in degrees; positive values are clockwise
largeArc chooses smaller or larger Arc
sweep chooses clockwise or counterclockwise Arc
xy end of Arc
### Example
### See Also rArcTo ArcSize Direction --- ## rArcTo 
void rArcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc,
            Direction sweep, SkScalar dx, SkScalar dy)
Append Arc to Path, relative to last Path Point. Arc is implemented by one or more Conic, weighted to describe part of Oval with radii (rx, ry) rotated by xAxisRotate degrees. Arc curves from last Path Point (x0, y0) to end Point: (x0 + dx, y0 + dy), choosing one of four possible routes: clockwise or counterclockwise, and smaller or larger. If Path is empty, the start Arc Point is (0, 0). Arc sweep is always less than 360 degrees. arcTo appends Line to end Point if either radii are zero, or if last Path Point equals end Point. arcTo scales radii (rx, ry) to fit last Path Point and end Point if both are greater than zero but too small to describe an arc. arcTo appends up to four Conic curves. arcTo implements the functionality of SVG Arc, although SVG "" value is opposite the integer value of sweep; SVG "" uses 1 for clockwise, while kCW Direction cast to int is zero. ### Parameters
rx radius in x before x-axis rotation
ry radius in y before x-axis rotation
xAxisRotate x-axis rotation in degrees; positive values are clockwise
largeArc chooses smaller or larger Arc
sweep chooses clockwise or counterclockwise Arc
dx x offset end of Arc from last Path Point
dy y offset end of Arc from last Path Point
### Example
### See Also arcTo ArcSize Direction --- ## close 
void close()
Append kClose Verb to Path. A closed Contour connects the first and last Point with Line, forming a continuous loop. Open and closed Contour draw the same with SkPaint::kFill Style. With SkPaint::kStroke Style, open Contour draws Paint Stroke Cap at Contour start and end; closed Contour draws Paint Stroke Join at Contour start and end. close has no effect if Path is empty or last Path Verb is kClose Verb. ### Example
### See Also --- ## IsInverseFillType 
static bool IsInverseFillType(FillType fill)
Returns true if fill is inverted and Path with fill represents area outside of its geometric bounds. | FillType | is inverse | | --- | --- | | kWinding FillType | false | | kEvenOdd FillType | false | | kInverseWinding FillType | true | | kInverseEvenOdd FillType | true | ### Parameters
fill one of: kWinding FillType, kEvenOdd FillType, kInverseWinding FillType, kInverseEvenOdd FillType
### Return Value true if Path fills outside its bounds ### Example
#### Example Output ~~~~ IsInverseFillType(kWinding_FillType) == false IsInverseFillType(kEvenOdd_FillType) == false IsInverseFillType(kInverseWinding_FillType) == true IsInverseFillType(kInverseEvenOdd_FillType) == true ~~~~
### See Also FillType getFillType setFillType ConvertToNonInverseFillType --- ## ConvertToNonInverseFillType 
static FillType ConvertToNonInverseFillType(FillType fill)
Returns equivalent Fill Type representing Path fill inside its bounds. . | FillType | inside FillType | | --- | --- | | kWinding FillType | kWinding FillType | | kEvenOdd FillType | kEvenOdd FillType | | kInverseWinding FillType | kWinding FillType | | kInverseEvenOdd FillType | kEvenOdd FillType | ### Parameters
fill one of: kWinding FillType, kEvenOdd FillType, kInverseWinding FillType, kInverseEvenOdd FillType
### Return Value fill, or kWinding FillType or kEvenOdd FillType if fill is inverted ### Example
#### Example Output ~~~~ ConvertToNonInverseFillType(kWinding_FillType) == kWinding_FillType ConvertToNonInverseFillType(kEvenOdd_FillType) == kEvenOdd_FillType ConvertToNonInverseFillType(kInverseWinding_FillType) == kWinding_FillType ConvertToNonInverseFillType(kInverseEvenOdd_FillType) == kEvenOdd_FillType ~~~~
### See Also FillType getFillType setFillType IsInverseFillType --- ## ConvertConicToQuads 
static int ConvertConicToQuads(const SkPoint& p0, const SkPoint& p1,
                               const SkPoint& p2, SkScalar w, SkPoint pts[],
                               int pow2)
Approximates Conic with Quad array. Conic is constructed from start Point p0, control Point p1, end Point p2, and weight w. Quad array is stored in pts; this storage is supplied by caller. Maximum Quad count is 2 to the pow2. Every third point in array shares last Point of previous Quad and first Point of next Quad. Maximum pts storage size is given by: (1 + 2 * (1 << pow2)) * sizeof(SkPoint). Returns Quad count used the approximation, which may be smaller than the number requested. Conic Weight determines the amount of influence Conic control point has on the curve. w less than one represents an elliptical section. w greater than one represents a hyperbolic section. w equal to one represents a parabolic section. Two Quad curves are sufficient to approximate an elliptical Conic with a sweep of up to 90 degrees; in this case, set pow2 to one. ### Parameters
p0 Conic start Point
p1 Conic control Point
p2 Conic end Point
w Conic weight
pts storage for Quad array
pow2 Quad count, as power of two, normally 0 to 5 (1 to 32 Quad curves)
### Return Value number of Quad curves written to pts ### Example
A pair of Quad curves are drawn in red on top of the elliptical Conic curve in black. The middle curve is nearly circular. The top-right curve is parabolic, which can be drawn exactly with a single Quad.
### See Also Conic Quad --- ## isRect 
bool isRect(SkRect* rect, bool* isClosed = nullptr,
            Direction* direction = nullptr) const
Returns true if Path is equivalent to Rect when filled. If false: rect, isClosed, and direction are unchanged. If true: rect, isClosed, and direction are written to if not nullptr. rect may be smaller than the Path bounds. Path bounds may include kMove Verb points that do not alter the area drawn by the returned rect. ### Parameters
rect storage for bounds of Rect; may be nullptr
isClosed storage set to true if Path is closed; may be nullptr
direction storage set to Rect direction; may be nullptr
### Return Value true if Path contains Rect ### Example
After addRect, isRect returns true. Following moveTo permits isRect to return true, but following lineTo does not. addPoly returns true even though rect is not closed, and one side of rect is made up of consecutive line segments.
#### Example Output ~~~~ empty is not rect addRect is rect (10, 20, 30, 40); is closed; direction CW moveTo is rect (10, 20, 30, 40); is closed; direction CW lineTo is not rect addPoly is rect (0, 0, 80, 80); is not closed; direction CCW ~~~~
### See Also computeTightBounds conservativelyContainsRect getBounds isConvex isLastContourClosed isNestedFillRects --- ## isNestedFillRects 
bool isNestedFillRects(SkRect rect[2], Direction dirs[2] = nullptr) const
Returns true if Path is equivalent to nested Rect pair when filled. If false, rect and dirs are unchanged. If true, rect and dirs are written to if not nullptr: setting rect[0] to outer Rect, and rect[1] to inner Rect; setting dirs[0] to Direction of outer Rect, and dirs[1] to Direction of inner Rect. ### Parameters
rect storage for Rect pair; may be nullptr
dirs storage for Direction pair; may be nullptr
### Return Value true if Path contains nested Rect pair ### Example
#### Example Output ~~~~ outer (7.5, 17.5, 32.5, 42.5); direction CW inner (12.5, 22.5, 27.5, 37.5); direction CCW ~~~~
### See Also computeTightBounds conservativelyContainsRect getBounds isConvex isLastContourClosed isRect --- ## addRect 
void addRect(const SkRect& rect, Direction dir = kCW_Direction)
Add Rect to Path, appending kMove Verb, three kLine Verb, and kClose Verb, starting with top-left corner of Rect; followed by top-right, bottom-right, and bottom-left if dir is kCW Direction; or followed by bottom-left, bottom-right, and top-right if dir is kCCW Direction. ### Parameters
rect Rect to add as a closed contour
dir Direction to wind added contour
### Example
The left Rect dashes starting at the top-left corner, to the right. The right Rect dashes starting at the top-left corner, towards the bottom.
### See Also SkCanvas::drawRect Direction --- 
void addRect(const SkRect& rect, Direction dir, unsigned start)
Add Rect to Path, appending kMove Verb, three kLine Verb, and kClose Verb. If dir is kCW Direction, Rect corners are added clockwise; if dir is kCCW Direction, Rect corners are added counterclockwise. start determines the first corner added. | start | first corner | | --- | --- | | 0 | top-left | | 1 | top-right | | 2 | bottom-right | | 3 | bottom-left | ### Parameters
rect Rect to add as a closed contour
dir Direction to wind added contour
start initial corner of Rect to add
### Example
The arrow is just after the initial corner and points towards the next corner appended to Path.
### See Also SkCanvas::drawRect Direction --- 
void addRect(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom,
             Direction dir = kCW_Direction)
Add Rect (left, top, right, bottom) to Path, appending kMove Verb, three kLine Verb, and kClose Verb, starting with top-left corner of Rect; followed by top-right, bottom-right, and bottom-left if dir is kCW Direction; or followed by bottom-left, bottom-right, and top-right if dir is kCCW Direction. ### Parameters
left smaller x of Rect
top smaller y of Rect
right larger x of Rect
bottom larger y of Rect
dir Direction to wind added contour
### Example
The left Rect dashes start at the top-left corner, and continue to the right. The right Rect dashes start at the top-left corner, and continue down.
### See Also SkCanvas::drawRect Direction --- ## addOval 
void addOval(const SkRect& oval, Direction dir = kCW_Direction)
Add Oval to path, appending kMove Verb, four kConic Verb, and kClose Verb. Oval is upright ellipse bounded by Rect oval with radii equal to half oval width and half oval height. Oval begins at (oval.fRight, oval.centerY()) and continues clockwise if dir is kCW Direction, counterclockwise if dir is kCCW Direction. This form is identical to ### Parameters
oval bounds of ellipse added
dir Direction to wind ellipse
### Example
### See Also SkCanvas::drawOval Direction Oval --- 
void addOval(const SkRect& oval, Direction dir, unsigned start)
Add Oval to Path, appending kMove Verb, four kConic Verb, and kClose Verb. Oval is upright ellipse bounded by Rect oval with radii equal to half oval width and half oval height. Oval begins at start and continues clockwise if dir is kCW Direction, counterclockwise if dir is kCCW Direction. | start | Point | | --- | --- | | 0 | oval.centerX(), oval.fTop | | 1 | oval.fRight, oval.centerY() | | 2 | oval.centerX(), oval.fBottom | | 3 | oval.fLeft, oval.centerY() | ### Parameters
oval bounds of ellipse added
dir Direction to wind ellipse
start index of initial point of ellipse
### Example
### See Also SkCanvas::drawOval Direction Oval --- ## addCircle 
void addCircle(SkScalar x, SkScalar y, SkScalar radius,
               Direction dir = kCW_Direction)
Add Circle centered at (x, y) of size radius to Path, appending kMove Verb, four kConic Verb, and kClose Verb. Circle begins at: (x + radius, y), continuing clockwise if dir is kCW Direction, and counterclockwise if dir is kCCW Direction. Has no effect if radius is zero or negative. ### Parameters
x center of Circle
y center of Circle
radius distance from center to edge
dir Direction to wind Circle
### Example
### See Also SkCanvas::drawCircle Direction Circle --- ## addArc 
void addArc(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle)
Append Arc to Path, as the start of new Contour. Arc added is part of ellipse bounded by oval, from startAngle through sweepAngle. Both startAngle and sweepAngle are measured in degrees, where zero degrees is aligned with the positive x-axis, and positive sweeps extends Arc clockwise. If sweepAngle <= -360, or sweepAngle >= 360; and startAngle modulo 90 is nearly zero, append Oval instead of Arc. Otherwise, sweepAngle values are treated modulo 360, and Arc may or may not draw depending on numeric rounding. ### Parameters
oval bounds of ellipse containing Arc
startAngle starting angle of Arc in degrees
sweepAngle sweep, in degrees. Positive is clockwise; treated modulo 360
### Example
The middle row of the left and right columns draw differently from the entries above and below because sweepAngle is outside of the range of +/-360, and startAngle modulo 90 is not zero.
### See Also Arc arcTo SkCanvas::drawArc --- ## addRoundRect 
void addRoundRect(const SkRect& rect, SkScalar rx, SkScalar ry,
                  Direction dir = kCW_Direction)
Append Round Rect to Path, creating a new closed Contour. Round Rect has bounds equal to rect; each corner is 90 degrees of an ellipse with radii (rx, ry). If dir is kCW Direction, Round Rect starts at top-left of the lower-left corner and winds clockwise. If dir is kCCW Direction, Round Rect starts at the bottom-left of the upper-left corner and winds counterclockwise. If either rx or ry is too large, rx and ry are scaled uniformly until the corners fit. If rx or ry is less than or equal to zero, addRoundRect appends Rect rect to Path. After appending, Path may be empty, or may contain: Rect, Oval, or RoundRect. ### Parameters
rect bounds of Round Rect
rx x-radius of rounded corners on the Round Rect
ry y-radius of rounded corners on the Round Rect
dir Direction to wind Round Rect
### Example
If either radius is zero, path contains Rect and is drawn red. If sides are only radii, path contains Oval and is drawn blue. All remaining path draws are convex, and are drawn in gray; no paths constructed from addRoundRect are concave, so none are drawn in green.
### See Also addRRect SkCanvas::drawRoundRect --- 
void addRoundRect(const SkRect& rect, const SkScalar radii[],
                  Direction dir = kCW_Direction)
Append Round Rect to Path, creating a new closed Contour. Round Rect has bounds equal to rect; each corner is 90 degrees of an ellipse with radii from the array. | radii index | location | | --- | --- | | 0 | x-radius of top-left corner | | 1 | y-radius of top-left corner | | 2 | x-radius of top-right corner | | 3 | y-radius of top-right corner | | 4 | x-radius of bottom-right corner | | 5 | y-radius of bottom-right corner | | 6 | x-radius of bottom-left corner | | 7 | y-radius of bottom-left corner | If dir is kCW Direction, Round Rect starts at top-left of the lower-left corner and winds clockwise. If dir is kCCW Direction, Round Rect starts at the bottom-left of the upper-left corner and winds counterclockwise. If both radii on any side of rect exceed its length, all radii are scaled uniformly until the corners fit. If either radius of a corner is less than or equal to zero, both are treated as zero. After appending, Path may be empty, or may contain: Rect, Oval, or RoundRect. ### Parameters
rect bounds of Round Rect
radii array of 8 SkScalar values, a radius pair for each corner
dir Direction to wind Round Rect
### Example
### See Also addRRect SkCanvas::drawRoundRect --- ## addRRect 
void addRRect(const SkRRect& rrect, Direction dir = kCW_Direction)
Add rrect to Path, creating a new closed Contour. If dir is kCW Direction, rrect starts at top-left of the lower-left corner and winds clockwise. If dir is kCCW Direction, rrect starts at the bottom-left of the upper-left corner and winds counterclockwise. After appending, Path may be empty, or may contain: Rect, Oval, or Round Rect. ### Parameters
rrect bounds and radii of rounded rectangle
dir Direction to wind Round Rect
### Example
### See Also addRoundRect SkCanvas::drawRRect --- 
void addRRect(const SkRRect& rrect, Direction dir, unsigned start)
Add rrect to Path, creating a new closed Contour. If dir is kCW Direction, rrect winds clockwise; if dir is kCCW Direction, rrect winds counterclockwise. start determines the first point of rrect to add. | start | location | | --- | --- | | 0 | right of top-left corner | | 1 | left of top-right corner | | 2 | bottom of top-right corner | | 3 | top of bottom-right corner | | 4 | left of bottom-right corner | | 5 | right of bottom-left corner | | 6 | top of bottom-left corner | | 7 | bottom of top-left corner | After appending, Path may be empty, or may contain: Rect, Oval, or Round Rect. ### Parameters
rrect bounds and radii of rounded rectangle
dir Direction to wind Round Rect
start index of initial point of Round Rect
### Example
### See Also addRoundRect SkCanvas::drawRRect --- ## addPoly 
void addPoly(const SkPoint pts[], int count, bool close)
Add Contour created from Line array, adding (count - 1) Line segments. Contour added starts at pts[0], then adds a line for every additional Point in pts array. If close is true,appends kClose Verb to Path, connecting pts[count - 1] and pts[0]. If count is zero, append kMove Verb to path. Has no effect if count is less than one. ### Parameters
pts array of Line sharing end and start Point
count length of Point array
close true to add Line connecting Contour end and start
### Example
### See Also SkCanvas::drawPoints --- ## Enum SkPath::AddPathMode 
enum AddPathMode {
kAppend AddPathMode, 
kExtend AddPathMode, 
};
AddPathMode chooses how addPath appends. Adding one Path to another can extend the last Contour or start a new Contour. ### Constants
SkPath::kAppend_AddPathMode Path Verbs, Points, and Conic_Weights are appended to destination unaltered.Since Path Verb Array begins with kMove Verb if src is not empty, this starts a new Contour.
SkPath::kExtend_AddPathMode If destination is closed or empty, start a new Contour. If destinationis not empty, add Line from Last Point to added Path first Point. Skip added Path initial kMove Verb, then append remining Verbs, Points, and Conic Weights.
### Example
test is built from path, open on the top row, and closed on the bottom row. The left column uses kAppend AddPathMode; the right uses kExtend AddPathMode. The top right composition is made up of one contour; the other three have two.
### See Also addPath reverseAddPath ## addPath 
void addPath(const SkPath& src, SkScalar dx, SkScalar dy,
             AddPathMode mode = kAppend_AddPathMode)
Append src to Path, offset by (dx, dy). If mode is kAppend AddPathMode, src Verb Array, Point Array, and Conic Weights are added unaltered. If mode is kExtend AddPathMode, add Line before appending Verbs, Points, and Conic Weights. ### Parameters
src Path Verbs, Points, and Conic Weights to add
dx offset added to src Point Array x coordinates
dy offset added to src Point Array y coordinates
mode kAppend AddPathMode or kExtend AddPathMode
### Example
### See Also AddPathMode offset reverseAddPath --- 
void addPath(const SkPath& src, AddPathMode mode = kAppend_AddPathMode)
Append src to Path. If mode is kAppend AddPathMode, src Verb Array, Point Array, and Conic Weights are added unaltered. If mode is kExtend AddPathMode, add Line before appending Verbs, Points, and Conic Weights. ### Parameters
src Path Verbs, Points, and Conic Weights to add
mode kAppend AddPathMode or kExtend AddPathMode
### Example
### See Also AddPathMode reverseAddPath --- 
void addPath(const SkPath& src, const SkMatrix& matrix,
             AddPathMode mode = kAppend_AddPathMode)
Append src to Path, transformed by matrix. Transformed curves may have different Verbs, Points, and Conic Weights. If mode is kAppend AddPathMode, src Verb Array, Point Array, and Conic Weights are added unaltered. If mode is kExtend AddPathMode, add Line before appending Verbs, Points, and Conic Weights. ### Parameters
src Path Verbs, Points, and Conic Weights to add
matrix transform applied to src
mode kAppend AddPathMode or kExtend AddPathMode
### Example
### See Also AddPathMode transform offset reverseAddPath --- ## reverseAddPath 
void reverseAddPath(const SkPath& src)
Append src to Path, from back to front. Reversed src always appends a new Contour to Path. ### Parameters
src Path Verbs, Points, and Conic Weights to add
### Example
### See Also AddPathMode transform offset addPath --- ## offset 
void offset(SkScalar dx, SkScalar dy, SkPath* dst) const
Offset Point Array by (dx, dy). Offset Path replaces dst. If dst is nullptr, Path is replaced by offset data. ### Parameters
dx offset added to Point Array x coordinates
dy offset added to Point Array y coordinates
dst overwritten, translated copy of Path; may be nullptr
### Example
### See Also addPath transform --- 
void offset(SkScalar dx, SkScalar dy)
Offset Point Array by (dx, dy). Path is replaced by offset data. ### Parameters
dx offset added to Point Array x coordinates
dy offset added to Point Array y coordinates
### Example
### See Also addPath transform SkCanvas::translate() --- ## transform 
void transform(const SkMatrix& matrix, SkPath* dst) const
Transform Verb Array, Point Array, and weight by matrix. transform may change Verbs and increase their number. Transformed Path replaces dst; if dst is nullptr, original data is replaced. ### Parameters
matrix Matrix to apply to Path
dst overwritten, transformed copy of Path; may be nullptr
### Example
### See Also addPath offset SkCanvas::concat() SkMatrix --- 
void transform(const SkMatrix& matrix)
Transform Verb Array, Point Array, and weight by matrix. transform may change Verbs and increase their number. Path is replaced by transformed data. ### Parameters
matrix Matrix to apply to Path
### Example
### See Also addPath offset SkCanvas::concat() SkMatrix --- ## Last Point Path is defined cumulatively, often by adding a segment to the end of last Contour. Last Point of Contour is shared as first Point of added Line or Curve. Last Point can be read and written directly with getLastPt and setLastPt. ## getLastPt 
bool getLastPt(SkPoint* lastPt) const
Returns Last Point on Path in lastPt. Returns false if Point Array is empty, storing (0, 0) if lastPt is not nullptr. ### Parameters
lastPt storage for final Point in Point Array; may be nullptr
### Return Value true if Point Array contains one or more Points ### Example
#### Example Output ~~~~ last point: 35.2786, 52.9772 ~~~~
### See Also setLastPt --- ## setLastPt 
void setLastPt(SkScalar x, SkScalar y)
Set Last Point to (x, y). If Point Array is empty, append kMove Verb to Verb Array and (x, y) to Point Array. ### Parameters
x set x-coordinate of Last Point
y set y-coordinate of Last Point
### Example
### See Also getLastPt --- 
void setLastPt(const SkPoint& p)
Set the last point on the path. If no points have been added, ### Parameters
p set value of Last Point
### Example
### See Also getLastPt --- ## Enum SkPath::SegmentMask 
enum SegmentMask {
kLine SegmentMask = 1 << 0,
kQuad SegmentMask = 1 << 1,
kConic SegmentMask = 1 << 2,
kCubic SegmentMask = 1 << 3,
};
SegmentMask constants correspond to each drawing Verb type in Path; for instance, if Path only contains Lines, only the kLine SegmentMask bit is set. ### Constants
SkPath::kLine_SegmentMask 1Set if Verb Array contains kLine Verb.
SkPath::kQuad_SegmentMask 2Set if Verb Array contains kQuad Verb. Note that conicTo may add a Quad.
SkPath::kConic_SegmentMask 4Set if Verb Array contains kConic Verb.
SkPath::kCubic_SegmentMask 8Set if Verb Array contains kCubic Verb.
### Example
When conicTo has a weight of one, Quad is added to Path.
#### Example Output ~~~~ Path kConic_SegmentMask is clear Path kQuad_SegmentMask is set ~~~~
### See Also getSegmentMasks Verb ## getSegmentMasks 
uint32_t getSegmentMasks() const
Returns a mask, where each set bit corresponds to a SegmentMask constant if Path contains one or more Verbs of that type. Returns zero if Path contains no Lines, or Curves: Quads, Conics, or Cubics. getSegmentMasks returns a cached result; it is very fast. ### Return Value SegmentMask bits or zero ### Example
#### Example Output ~~~~ mask quad set ~~~~
### See Also getSegmentMasks Verb --- ## contains 
bool contains(SkScalar x, SkScalar y) const
Returns true if the point (x, y) is contained by Path, taking into account FillType. | FillType | contains returns true if Point is enclosed by | | --- | --- | | kWinding FillType | a non-zero sum of Contour Directions. | | kEvenOdd FillType | an odd number of Contours. | | kInverseWinding FillType | a zero sum of Contour Directions. | | kInverseEvenOdd FillType | and even number of Contours. | ### Parameters
x x-coordinate of containment test
y y-coordinate of containment test
### Return Value true if Point is in Path ### Example
### See Also conservativelyContainsRect Fill Type Op --- ## dump 
void dump(SkWStream* stream, bool forceClose, bool dumpAsHex) const
Writes text representation of Path to stream. If stream is nullptr, writes to standard output. Set forceClose to true to get edges used to fill Path. Set dumpAsHex true to generate exact binary representations of floating point numbers used in Point Array and Conic Weights. ### Parameters
stream writable Stream receiving Path text representation; may be nullptr
forceClose true if missing kClose Verb is output
dumpAsHex true if SkScalar values are written as hexadecimal
### Example
#### Example Output ~~~~ path.setFillType(SkPath::kWinding_FillType); path.moveTo(0, 0); path.quadTo(20, 30, 40, 50); path.setFillType(SkPath::kWinding_FillType); path.moveTo(SkBits2Float(0x00000000), SkBits2Float(0x00000000)); // 0, 0 path.quadTo(SkBits2Float(0x41a00000), SkBits2Float(0x41f00000), SkBits2Float(0x42200000), SkBits2Float(0x42480000)); // 20, 30, 40, 50 path.setFillType(SkPath::kWinding_FillType); path.moveTo(0, 0); path.quadTo(20, 30, 40, 50); path.lineTo(0, 0); path.close(); path.setFillType(SkPath::kWinding_FillType); path.moveTo(SkBits2Float(0x00000000), SkBits2Float(0x00000000)); // 0, 0 path.quadTo(SkBits2Float(0x41a00000), SkBits2Float(0x41f00000), SkBits2Float(0x42200000), SkBits2Float(0x42480000)); // 20, 30, 40, 50 path.lineTo(SkBits2Float(0x00000000), SkBits2Float(0x00000000)); // 0, 0 path.close(); ~~~~
### See Also SkRect::dump() SkRRect::dump() SkPathMeasure::dump() --- 
void dump() const
Writes text representation of Path to standard output. The representation may be directly compiled as C++ code. Floating point values are written with limited precision; it may not be possible to reconstruct original Path from output. ### Example
#### Example Output ~~~~ path.setFillType(SkPath::kWinding_FillType); path.moveTo(0, 0); path.lineTo(0.857143f, 0.666667f); path is not equal to copy ~~~~
### See Also dumpHex SkRect::dump() SkRRect::dump() SkPathMeasure::dump() writeToMemory --- ## dumpHex 
void dumpHex() const
Writes text representation of Path to standard output. The representation may be directly compiled as C++ code. Floating point values are written in hexadecimal to preserve their exact bit pattern. The output reconstructs the original Path. Use instead of dump when submittingbug reports against Skia. ### Example
#### Example Output ~~~~ path.setFillType(SkPath::kWinding_FillType); path.moveTo(SkBits2Float(0x00000000), SkBits2Float(0x00000000)); // 0, 0 path.lineTo(SkBits2Float(0x3f5b6db7), SkBits2Float(0x3f2aaaab)); // 0.857143f, 0.666667f path is equal to copy ~~~~
### See Also dump --- ## writeToMemory 
size_t writeToMemory(void* buffer) const
Writes Path to buffer, returning the number of bytes written. Pass nullptr to obtain the storage size. Writes Fill Type, Verb Array, Point Array, Conic Weight, and additionally writes computed information like Convexity and bounds. Use only be used in concert with readFromMemory; the format used for Path in memory is not guaranteed. ### Parameters
buffer storage for Path; may be nullptr
### Return Value size of storage required for Path; always a multiple of 4 ### Example
#### Example Output ~~~~ path is equal to copy ~~~~
### See Also serialize readFromMemory dump dumpHex --- ## serialize 
sk_sp<SkData> serialize() const
Write Path to buffer, returning the buffer written to, wrapped in Data. serialize writes Fill Type, Verb Array, Point Array, Conic Weight, and additionally writes computed information like Convexity and bounds. serialize should only be used in concert with readFromMemory. The format used for Path in memory is not guaranteed. ### Return Value Path data wrapped in Data buffer ### Example
#### Example Output ~~~~ path is equal to copy ~~~~
### See Also writeToMemory readFromMemory dump dumpHex --- ## readFromMemory 
size_t readFromMemory(const void* buffer, size_t length)
Initializes Path from buffer of size length. Returns zero if the buffer is data is inconsistent, or the length is too small. Reads Fill Type, Verb Array, Point Array, Conic Weight, and additionally reads computed information like Convexity and bounds. Used only in concert with writeToMemory; the format used for Path in memory is not guaranteed. ### Parameters
buffer storage for Path
length buffer size in bytes; must be multiple of 4
### Return Value number of bytes read, or zero on failure ### Example
#### Example Output ~~~~ length = 60; returned by readFromMemory = 0 length = 68; returned by readFromMemory = 64 ~~~~
### See Also writeToMemory --- # Generation ID Generation ID provides a quick way to check if Verb Array, Point Array, or Conic Weight has changed. Generation ID is not a hash; identical Paths will not necessarily have matching Generation IDs. Empty Paths have a Generation ID of one. ## getGenerationID 
uint32_t getGenerationID() const
Returns a non-zero, globally unique value. A different value is returned if Verb Array, Point Array, or Conic Weight changes. Setting Fill Type does not change Generation ID. Each time the path is modified, a different Generation ID will be returned. ### Return Value non-zero, globally unique value ### Example
#### Example Output ~~~~ empty genID = 1 1st lineTo genID = 2 empty genID = 1 2nd lineTo genID = 3 ~~~~
### See Also operator==(const SkPath& a, const SkPath& b) --- ## isValid 
bool isValid() const
Returns if Path data is consistent. Corrupt Path data is detected if internal values are out of range or internal storage does not match array dimensions. ### Return Value true if Path data is consistent --- ## pathRefIsValid 
bool pathRefIsValid() const
Returns if Path data is consistent. To be deprecated soon. ### Return Value true if Path data is consistent --- # Class SkPath::Iter Iterates through Verb Array, and associated Point Array and Conic Weight. Provides options to treat open Contours as closed, and to ignore degenerate data. 
class Iter {
public:
Iter();
Iter(const SkPath& path, bool forceClose);
void setPath(const SkPath& path, bool forceClose);
Verb next(SkPoint pts[4], bool doConsumeDegenerates = true, bool exact = false);
SkScalar conicWeight const;
bool isCloseLine const;
bool isClosedContour const;
};
### Example
Ignoring the actual Verbs and replacing them with Quads rounds the path of the glyph.
### See Also RawIter ## Iter 
Iter()
Initializes Iter with an empty Path. next on Iter returns kDone Verb. Call setPath to initialize Iter at a later time. ### Return Value Iter of empty Path ### Example
#### Example Output ~~~~ iter is done iter is done ~~~~
### See Also setPath --- 
Iter(const SkPath& path, bool forceClose)
Sets Iter to return elements of Verb Array, Point Array, and Conic Weight in path. If forceClose is true, Iter will add kLine Verb and kClose Verb after each open Contour. path is not altered. ### Parameters
path Path to iterate
forceClose true if open Contours generate kClose Verb
### Return Value Iter of path ### Example
#### Example Output ~~~~ open: kMove_Verb {0, 0}, kQuad_Verb {0, 0}, {10, 20}, {30, 40}, kDone_Verb closed: kMove_Verb {0, 0}, kQuad_Verb {0, 0}, {10, 20}, {30, 40}, kLine_Verb {30, 40}, {0, 0}, kClose_Verb {0, 0}, kDone_Verb ~~~~
### See Also setPath --- ## setPath 
void setPath(const SkPath& path, bool forceClose)
Sets Iter to return elements of Verb Array, Point Array, and Conic Weight in path. If forceClose is true, Iter will add kLine Verb and kClose Verb after each open Contour. path is not altered. ### Parameters
path Path to iterate
forceClose true if open Contours generate kClose Verb
### Example
#### Example Output ~~~~ quad open: kMove_Verb {0, 0}, kQuad_Verb {0, 0}, {10, 20}, {30, 40}, kDone_Verb conic closed: kMove_Verb {0, 0}, kConic_Verb {0, 0}, {1, 2}, {3, 4}, weight = 0.5 kLine_Verb {3, 4}, {0, 0}, kClose_Verb {0, 0}, kDone_Verb ~~~~
### See Also Iter(const SkPath& path, bool forceClose) --- ## next 
Verb next(SkPoint pts[4], bool doConsumeDegenerates = true, bool exact = false)
Returns next Verb in Verb Array, and advances Iter. When Verb Array is exhausted, returns kDone Verb. Zero to four Points are stored in pts, depending on the returned Verb. If doConsumeDegenerates is true, skip consecutive kMove Verb entries, returning only the last in the series; and skip very small Lines, Quads, and Conics; and skip kClose Verb following kMove Verb. if doConsumeDegenerates is true and exact is true, only skip Lines, Quads, and Conics with zero lengths. ### Parameters
pts storage for Point data describing returned Verb
doConsumeDegenerates if true, skip degenerate Verbs
exact skip zero length curves
### Return Value next Verb from Verb Array ### Example
skip degenerate skips the first in a kMove Verb pair, the kMove Verb followed by the kClose Verb, the zero length Line and the very small Line. skip degenerate if exact skips the same as skip degenerate, but shows the very small Line. skip none shows all of the Verbs and Points in Path.
#### Example Output ~~~~ skip degenerate: kMove_Verb {20, 20}, kQuad_Verb {20, 20}, {10, 20}, {30, 40}, kDone_Verb skip degenerate if exact: kMove_Verb {20, 20}, kQuad_Verb {20, 20}, {10, 20}, {30, 40}, kMove_Verb {30, 30}, kLine_Verb {30, 30}, {30.00001, 30}, kDone_Verb skip none: kMove_Verb {10, 10}, kMove_Verb {20, 20}, kQuad_Verb {20, 20}, {10, 20}, {30, 40}, kMove_Verb {1, 1}, kClose_Verb {1, 1}, kMove_Verb {30, 30}, kLine_Verb {30, 30}, {30, 30}, kMove_Verb {30, 30}, kLine_Verb {30, 30}, {30.00001, 30}, kDone_Verb ~~~~
### See Also Verb IsLineDegenerate IsCubicDegenerate IsQuadDegenerate --- ## conicWeight 
SkScalar conicWeight() const
Returns Conic Weight if next returned kConic Verb. If next has not been called, or next did not return kConic Verb, result is undefined. ### Return Value Conic Weight for Conic Points returned by next ### Example
#### Example Output ~~~~ first verb is move next verb is conic conic points: {0,0}, {1,2}, {3,4} conic weight: 0.5 ~~~~
### See Also Conic Weight --- ## isCloseLine 
bool isCloseLine() const
Returns true if last kLine Verb returned by next was generated by kClose Verb. When true, the end point returned by next is also the start point of Contour. If next has not been called, or next did not return kLine Verb, result is undefined. ### Return Value true if last kLine Verb was generated by kClose Verb ### Example
#### Example Output ~~~~ 1st verb is move moveTo point: {6,7} 2nd verb is conic 3rd verb is line line points: {3,4}, {6,7} line generated by close 4th verb is close ~~~~
### See Also close --- ## isClosedContour 
bool isClosedContour() const
Returns true if subsequent calls to next return kClose Verb before returning kMove Verb. if true, Contour Iter is processing may end with kClose Verb, or Iter may have been initialized with force close set to true. ### Return Value true if Contour is closed ### Example
#### Example Output ~~~~ without close(), forceClose is false: isClosedContour returns false with close(), forceClose is false: isClosedContour returns true without close(), forceClose is true : isClosedContour returns true with close(), forceClose is true : isClosedContour returns true ~~~~
### See Also Iter(const SkPath& path, bool forceClose) --- # Class SkPath::RawIter Iterates through Verb Array, and associated Point Array and Conic Weight. Verb Array, Point Array, and Conic Weight are returned unaltered. 
class RawIter {
public:
RawIter();
RawIter(const SkPath& path);
void setPath(const SkPath& path);
Verb next(SkPoint pts[4]);
Verb peek const;
SkScalar conicWeight const;
}
## RawIter 
RawIter()
Initializes RawIter with an empty Path. next on RawIter returns kDone Verb. Call setPath to initialize Iter at a later time. ### Return Value RawIter of empty Path --- 
RawIter(const SkPath& path)
Sets RawIter to return elements of Verb Array, Point Array, and Conic Weight in path. ### Parameters
path Path to iterate
### Return Value RawIter of path --- ## setPath 
void setPath(const SkPath& path)
Sets Iter to return elements of Verb Array, Point Array, and Conic Weight in path. ### Parameters
path Path to iterate
--- ## next 
Verb next(SkPoint pts[4])
Returns next Verb in Verb Array, and advances RawIter. When Verb Array is exhausted, returns kDone Verb. Zero to four Points are stored in pts, depending on the returned Verb. ### Parameters
pts storage for Point data describing returned Verb
### Return Value next Verb from Verb Array ### Example
#### Example Output ~~~~ kMove_Verb {50, 60}, kQuad_Verb {50, 60}, {10, 20}, {30, 40}, kClose_Verb {50, 60}, kMove_Verb {50, 60}, kLine_Verb {50, 60}, {30, 30}, kConic_Verb {30, 30}, {1, 2}, {3, 4}, weight = 0.5 kCubic_Verb {3, 4}, {-1, -2}, {-3, -4}, {-5, -6}, kDone_Verb ~~~~
### See Also peek --- ## peek 
Verb peek() const
Returns next Verb, but does not advance RawIter. ### Return Value next Verb from Verb Array ### Example
#### Example Output ~~~~ #Volatile peek Move == verb Move peek Quad == verb Quad peek Conic == verb Conic peek Cubic == verb Cubic peek Done == verb Done peek Done == verb Done ~~~~
### See Also next --- ## conicWeight 
SkScalar conicWeight() const
Returns Conic Weight if next returned kConic Verb. If next has not been called, or next did not return kConic Verb, result is undefined. ### Return Value Conic Weight for Conic Points returned by next ### Example
#### Example Output ~~~~ first verb is move next verb is conic conic points: {0,0}, {1,2}, {3,4} conic weight: 0.5 ~~~~
### See Also Conic Weight ---