Ben Wagner 51e15a69ce Use SkTextEncoding enum instead of macros.

Change-Id: I4b6259590fa0693ee0522b4999a1c0fe250b173d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/212504
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>

2019-05-07 20:54:16 +00:00

402 KiB

Raw Blame History

SkCanvas Reference

class SkCanvas {

    static std::unique_ptr<SkCanvas> MakeRasterDirect(const SkImageInfo& info, void* pixels,
                                                      size_t rowBytes,
                                                      const SkSurfaceProps* props = nullptr);
    static std::unique_ptr<SkCanvas> MakeRasterDirectN32(int width, int height, SkPMColor* pixels,
                                                         size_t rowBytes);
    SkCanvas();
    SkCanvas(int width, int height, const SkSurfaceProps* props = nullptr);
    explicit SkCanvas(const SkBitmap& bitmap);
    SkCanvas(const SkBitmap& bitmap, const SkSurfaceProps& props);
    virtual ~SkCanvas();
    SkMetaData& getMetaData();
    SkImageInfo imageInfo() const;
    bool getProps(SkSurfaceProps* props) const;
    void flush();
    virtual SkISize getBaseLayerSize() const;
    sk_sp<SkSurface> makeSurface(const SkImageInfo& info, const SkSurfaceProps* props = nullptr);
    virtual GrContext* getGrContext();
    void* accessTopLayerPixels(SkImageInfo* info, size_t* rowBytes, SkIPoint* origin = nullptr);
    SkRasterHandleAllocator::Handle accessTopRasterHandle() const;
    bool peekPixels(SkPixmap* pixmap);
    bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                    int srcX, int srcY);
    bool readPixels(const SkPixmap& pixmap, int srcX, int srcY);
    bool readPixels(const SkBitmap& bitmap, int srcX, int srcY);
    bool writePixels(const SkImageInfo& info, const void* pixels, size_t rowBytes, int x, int y);
    bool writePixels(const SkBitmap& bitmap, int x, int y);
    int save();
    int saveLayer(const SkRect* bounds, const SkPaint* paint);
    int saveLayer(const SkRect& bounds, const SkPaint* paint);
    int saveLayerPreserveLCDTextRequests(const SkRect* bounds, const SkPaint* paint);
    int saveLayerAlpha(const SkRect* bounds, U8CPU alpha);

    enum SaveLayerFlagsSet {
        kPreserveLCDText_SaveLayerFlag = 1 << 1,
        kInitWithPrevious_SaveLayerFlag = 1 << 2,
    };

    typedef uint32_t SaveLayerFlags;

    int saveLayer(const SaveLayerRec& layerRec);
    void restore();
    int getSaveCount() const;
    void restoreToCount(int saveCount);
    void translate(SkScalar dx, SkScalar dy);
    void scale(SkScalar sx, SkScalar sy);
    void rotate(SkScalar degrees);
    void rotate(SkScalar degrees, SkScalar px, SkScalar py);
    void skew(SkScalar sx, SkScalar sy);
    void concat(const SkMatrix& matrix);
    void setMatrix(const SkMatrix& matrix);
    void resetMatrix();
    void clipRect(const SkRect& rect, SkClipOp op, bool doAntiAlias);
    void clipRect(const SkRect& rect, SkClipOp op);
    void clipRect(const SkRect& rect, bool doAntiAlias = false);
    void clipRRect(const SkRRect& rrect, SkClipOp op, bool doAntiAlias);
    void clipRRect(const SkRRect& rrect, SkClipOp op);
    void clipRRect(const SkRRect& rrect, bool doAntiAlias = false);
    void clipPath(const SkPath& path, SkClipOp op, bool doAntiAlias);
    void clipPath(const SkPath& path, SkClipOp op);
    void clipPath(const SkPath& path, bool doAntiAlias = false);
    void clipRegion(const SkRegion& deviceRgn, SkClipOp op = SkClipOp::kIntersect);
    bool quickReject(const SkRect& rect) const;
    bool quickReject(const SkPath& path) const;
    SkRect getLocalClipBounds() const;
    bool getLocalClipBounds(SkRect* bounds) const;
    SkIRect getDeviceClipBounds() const;
    bool getDeviceClipBounds(SkIRect* bounds) const;
    void drawColor(SkColor color, SkBlendMode mode = SkBlendMode::kSrcOver);
    void clear(SkColor color);
    void discard();
    void drawPaint(const SkPaint& paint);

    enum PointMode {
        kPoints_PointMode,
        kLines_PointMode,
        kPolygon_PointMode,
    };

    void drawPoints(PointMode mode, size_t count, const SkPoint pts[], const SkPaint& paint);
    void drawPoint(SkScalar x, SkScalar y, const SkPaint& paint);
    void drawPoint(SkPoint p, const SkPaint& paint);
    void drawLine(SkScalar x0, SkScalar y0, SkScalar x1, SkScalar y1, const SkPaint& paint);
    void drawLine(SkPoint p0, SkPoint p1, const SkPaint& paint);
    void drawRect(const SkRect& rect, const SkPaint& paint);
    void drawIRect(const SkIRect& rect, const SkPaint& paint);
    void drawRegion(const SkRegion& region, const SkPaint& paint);
    void drawOval(const SkRect& oval, const SkPaint& paint);
    void drawRRect(const SkRRect& rrect, const SkPaint& paint);
    void drawDRRect(const SkRRect& outer, const SkRRect& inner, const SkPaint& paint);
    void drawCircle(SkScalar cx, SkScalar cy, SkScalar radius, const SkPaint& paint);
    void drawCircle(SkPoint center, SkScalar radius, const SkPaint& paint);
    void drawArc(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle,
                 bool useCenter, const SkPaint& paint);
    void drawRoundRect(const SkRect& rect, SkScalar rx, SkScalar ry, const SkPaint& paint);
    void drawPath(const SkPath& path, const SkPaint& paint);
    void drawImage(const SkImage* image, SkScalar left, SkScalar top,
                   const SkPaint* paint = nullptr);
    void drawImage(const sk_sp<SkImage>& image, SkScalar left, SkScalar top,
                   const SkPaint* paint = nullptr);

    enum SrcRectConstraint {
        kStrict_SrcRectConstraint,
        kFast_SrcRectConstraint,
    };

    void drawImageRect(const SkImage* image, const SkRect& src, const SkRect& dst,
                       const SkPaint* paint,
                       SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawImageRect(const SkImage* image, const SkIRect& isrc, const SkRect& dst,
                       const SkPaint* paint,
                       SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawImageRect(const SkImage* image, const SkRect& dst, const SkPaint* paint);
    void drawImageRect(const sk_sp<SkImage>& image, const SkRect& src, const SkRect& dst,
                       const SkPaint* paint,
                       SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawImageRect(const sk_sp<SkImage>& image, const SkIRect& isrc, const SkRect& dst,
                       const SkPaint* paint,
                       SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawImageRect(const sk_sp<SkImage>& image, const SkRect& dst, const SkPaint* paint);
    void drawImageNine(const SkImage* image, const SkIRect& center, const SkRect& dst,
                       const SkPaint* paint = nullptr);
    void drawImageNine(const sk_sp<SkImage>& image, const SkIRect& center, const SkRect& dst,
                       const SkPaint* paint = nullptr);
    void drawBitmap(const SkBitmap& bitmap, SkScalar left, SkScalar top,
                    const SkPaint* paint = nullptr);
    void drawBitmapRect(const SkBitmap& bitmap, const SkRect& src, const SkRect& dst,
                        const SkPaint* paint,
                        SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawBitmapRect(const SkBitmap& bitmap, const SkIRect& isrc, const SkRect& dst,
                        const SkPaint* paint,
                        SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawBitmapRect(const SkBitmap& bitmap, const SkRect& dst, const SkPaint* paint,
                        SrcRectConstraint constraint = kStrict_SrcRectConstraint);
    void drawBitmapNine(const SkBitmap& bitmap, const SkIRect& center, const SkRect& dst,
                        const SkPaint* paint = nullptr);
    void drawBitmapLattice(const SkBitmap& bitmap, const Lattice& lattice, const SkRect& dst,
                           const SkPaint* paint = nullptr);
    void drawImageLattice(const SkImage* image, const Lattice& lattice, const SkRect& dst,
                          const SkPaint* paint = nullptr);
    void drawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
                  const SkPaint& paint);
    void drawString(const char* string, SkScalar x, SkScalar y, const SkPaint& paint);
    void drawString(const SkString& string, SkScalar x, SkScalar y, const SkPaint& paint);
    void drawPosText(const void* text, size_t byteLength, const SkPoint pos[],
                     const SkPaint& paint);
    void drawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[], SkScalar constY,
                      const SkPaint& paint);
    void drawTextRSXform(const void* text, size_t byteLength, const SkRSXform xform[],
                         const SkRect* cullRect, const SkPaint& paint);
    void drawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y, const SkPaint& paint);
    void drawTextBlob(const sk_sp<SkTextBlob>& blob, SkScalar x, SkScalar y, const SkPaint& paint);
    void drawPicture(const SkPicture* picture);
    void drawPicture(const sk_sp<SkPicture>& picture);
    void drawPicture(const SkPicture* picture, const SkMatrix* matrix, const SkPaint* paint);
    void drawPicture(const sk_sp<SkPicture>& picture, const SkMatrix* matrix,
                     const SkPaint* paint);
    void drawVertices(const SkVertices* vertices, SkBlendMode mode, const SkPaint& paint);
    void drawVertices(const sk_sp<SkVertices>& vertices, SkBlendMode mode, const SkPaint& paint);
    void drawVertices(const SkVertices* vertices, const SkVertices::Bone bones[], int boneCount,
                      SkBlendMode mode, const SkPaint& paint);
    void drawVertices(const sk_sp<SkVertices>& vertices, const SkVertices::Bone bones[],
                      int boneCount, SkBlendMode mode, const SkPaint& paint);
    void drawPatch(const SkPoint cubics[12], const SkColor colors[4],
                   const SkPoint texCoords[4], SkBlendMode mode, const SkPaint& paint);
    void drawPatch(const SkPoint cubics[12], const SkColor colors[4],
                   const SkPoint texCoords[4], const SkPaint& paint);
    void drawAtlas(const SkImage* atlas, const SkRSXform xform[], const SkRect tex[],
                   const SkColor colors[], int count, SkBlendMode mode, const SkRect* cullRect,
                   const SkPaint* paint);
    void drawAtlas(const sk_sp<SkImage>& atlas, const SkRSXform xform[], const SkRect tex[],
                   const SkColor colors[], int count, SkBlendMode mode, const SkRect* cullRect,
                   const SkPaint* paint);
    void drawAtlas(const SkImage* atlas, const SkRSXform xform[], const SkRect tex[], int count,
                   const SkRect* cullRect, const SkPaint* paint);
    void drawAtlas(const sk_sp<SkImage>& atlas, const SkRSXform xform[], const SkRect tex[],
                   int count, const SkRect* cullRect, const SkPaint* paint);
    void drawDrawable(SkDrawable* drawable, const SkMatrix* matrix = nullptr);
    void drawDrawable(SkDrawable* drawable, SkScalar x, SkScalar y);
    void drawAnnotation(const SkRect& rect, const char key[], SkData* value);
    void drawAnnotation(const SkRect& rect, const char key[], const sk_sp<SkData>& value);
    virtual bool isClipEmpty() const;
    virtual bool isClipRect() const;
    const SkMatrix& getTotalMatrix() const;
};

Canvas provides an interface for drawing, and how the drawing is clipped and transformed. Canvas contains a stack of Matrix and Clip values.

Canvas and Paint together provide the state to draw into Surface or Device. Each Canvas draw call transforms the geometry of the object by the concatenation of all Matrix values in the stack. The transformed geometry is clipped by the intersection of all of Clip values in the stack. The Canvas draw calls use Paint to supply drawing state such as Color, Typeface, text size, stroke width, Shader and so on.

To draw to a pixel-based destination, create Raster_Surface or GPU_Surface. Request Canvas from Surface to obtain the interface to draw. Canvas generated by Raster_Surface draws to memory visible to the CPU. Canvas generated by GPU_Surface uses Vulkan or OpenGL to draw to the GPU.

To draw to a document, obtain Canvas from SVG_Canvas, Document_PDF, or Picture_Recorder. Document based Canvas and other Canvas subclasses reference Device describing the destination.

Canvas can be constructed to draw to Bitmap without first creating Raster_Surface. This approach may be deprecated in the future.

Canvas may be created directly when no Surface is required; some Canvas methods implicitly create Raster_Surface.

static std::unique_ptr<SkCanvas> MakeRasterDirect(const SkImageInfo& info, void* pixels,
                                                  size_t rowBytes,
                                                  const SkSurfaceProps* props = nullptr)

Allocates raster SkCanvas that will draw directly into pixels.

SkCanvas is returned if all parameters are valid. Valid parameters include: info dimensions are zero or positive; info contains SkColorType and SkAlphaType supported by raster surface; pixels is not nullptr; rowBytes is zero or large enough to contain info width pixels of SkColorType.

Pass zero for rowBytes to compute rowBytes from info width and size of pixel. If rowBytes is greater than zero, it must be equal to or greater than info width times bytes required for SkColorType.

Pixel buffer size should be info height times computed rowBytes. Pixels are not initialized. To access pixels after drawing, call flush() or peekPixels().

Parameters

info width, height, SkColorType, SkAlphaType, SkColorSpace, of raster surface;

width, or height, or both, may be zero

Parameters

`pixels`	pointer to destination pixels buffer
`rowBytes`	interval from one SkSurface row to the next, or zero
`props`	LCD striping orientation and setting for device independent fonts;

may be nullptr

Return Value

SkCanvas if all parameters are valid; otherwise, nullptr

Example

Allocates a three by three bitmap, clears it to white, and draws a black pixel in the center.

Example Output

---
-x-
---

Parameters

`width`	pixel column count on raster surface created; must be zero or greater
`height`	pixel row count on raster surface created; must be zero or greater
`pixels`	pointer to destination pixels buffer; buffer size should be height

times rowBytes

Parameters

rowBytes interval from one SkSurface row to the next, or zero

Return Value

SkCanvas if all parameters are valid; otherwise, nullptr

Example

Allocates a three by three bitmap, clears it to white, and draws a black pixel in the center.

Example Output

---
-x-
---

Return Value

empty SkCanvas

Example

Passes a placeholder to a function that requires one.

Example Output

rect stays rect is true
rect stays rect is false
rect stays rect is true

Parameters

`width`	zero or greater
`height`	zero or greater
`props`	LCD striping orientation and setting for device independent fonts;

may be nullptr

Return Value

SkCanvas placeholder with dimensions

Example

Example Output

canvas is empty

Parameters

bitmap width, height, SkColorType, SkAlphaType, and pixel

storage of raster surface

Return Value

SkCanvas that can be used to draw into bitmap

Example

The actual output depends on the installed fonts.

Example Output

-----
---x-
---x-
---x-
---x-
---x-
---x-
-----
---x-
---x-
-----

Parameters

bitmap width, height, SkColorType, SkAlphaType,

and pixel storage of raster surface

Parameters

props order and orientation of RGB striping; and whether to use

device independent fonts

Return Value

SkCanvas that can be used to draw into bitmap

Example

The actual output depends on the installed fonts.

Example Output

-----
---x-
---x-
---x-
---x-
---x-
---x-
-----
---x-
---x-
-----

Example

Canvas Layer draws into bitmap. saveLayerAlpha sets up an additional drawing surface that blends with the bitmap. When Layer goes out of scope, Layer destructor is called. The saved Layer is restored, drawing transparent letters.

Return Value

storage that can be read from and written to

Example

Example Output

before: (null)
during: Hello!
after: (null)

Return Value

dimensions and SkColorType of SkCanvas

Example

Example Output

emptyInfo == canvasInfo

Parameters

props storage for writable SkSurfaceProps

Return Value

true if SkSurfaceProps was copied

Example

Example Output

isRGB:0
isRGB:1

Return Value

integral width and height of base layer

Example

Example Output

clip=10,30
size=20,30

Parameters

`info`	width, height, SkColorType, SkAlphaType, and SkColorSpace
`props`	SkSurfaceProps to match; may be nullptr to match SkCanvas

Return Value

SkSurface matching info and props, or nullptr if no match is available

Example

Example Output

compatible != nullptr
size = 3, 4

Return Value

GPU context, if available; nullptr otherwise

Example

Parameters

`info`	storage for writable pixels' SkImageInfo; may be nullptr
`rowBytes`	storage for writable pixels' row bytes; may be nullptr
`origin`	storage for SkCanvas top layer origin, its top-left corner;

may be nullptr

Return Value

address of pixels, or nullptr if inaccessible

Example

Draws "ABC" on the device. Then draws "DEF" in Layer, and reads Layer to add a large dotted "DEF". Finally blends Layer with the device.

The Layer and blended result appear on the CPU and GPU but the large dotted "DEF" appear only on the CPU.

Return Value

context of custom allocation

Example

Example Output

context = skia

Parameters

pixmap storage for pixel state if pixels are readable; otherwise, ignored

Return Value

true if SkCanvas has direct access to pixels

Example

Example Output

width=256 height=256

Parameters

`dstInfo`	width, height, Color_Type, and Alpha_Type of dstPixels
`dstPixels`	storage for pixels; dstInfo.height() times dstRowBytes, or larger
`dstRowBytes`	size of one destination row; dstInfo.width() times pixel size, or larger
`srcX`	offset into readable pixels on x-axis; may be negative
`srcY`	offset into readable pixels on y-axis; may be negative

Return Value

true if pixels were copied

Example

A black circle drawn on a blue background provides an image to copy. readPixels copies one quarter of the canvas into each of the four corners. The copied quarter circles overdraw the original circle.

Example

Canvas returned by Raster_Surface has Premultiplied pixel values. clear() takes Unpremultiplied input with Color_Alpha equal 0x80 and RGB equal 0x55, 0xAA, 0xFF. RGB is multiplied by Color_Alpha to generate Premultiplied value 0x802B5580. readPixels converts pixel back to Unpremultiplied value 0x8056A9FF, introducing error.

Example Output

pixel = 802b5580
pixel = 8056a9ff

Parameters

`pixmap`	storage for pixels copied from Canvas
`srcX`	offset into readable pixels on x-axis; may be negative
`srcY`	offset into readable pixels on y-axis; may be negative

Return Value

true if pixels were copied

Example

clear() takes Unpremultiplied input with Color_Alpha equal 0x80 and RGB equal 0x55, 0xAA, 0xFF. RGB is multiplied by Color_Alpha to generate Premultiplied value 0x802B5580.

Example Output

pixel = 802b5580

Parameters

`bitmap`	storage for pixels copied from Canvas
`srcX`	offset into readable pixels on x-axis; may be negative
`srcY`	offset into readable pixels on y-axis; may be negative

Return Value

true if pixels were copied

Example

clear() takes Unpremultiplied input with Color_Alpha equal 0x80 and RGB equal 0x55, 0xAA, 0xFF. RGB is multiplied by Color_Alpha to generate Premultiplied value 0x802B5580.

Example Output

pixel = 802b5580

Parameters

`info`	width, height, Color_Type, and Alpha_Type of pixels
`pixels`	pixels to copy, of size info.height() times rowBytes, or larger
`rowBytes`	size of one row of pixels; info.width() times pixel size, or larger
`x`	offset into Canvas writable pixels on x-axis; may be negative
`y`	offset into Canvas writable pixels on y-axis; may be negative

Return Value

true if pixels were written to Canvas

Example

Parameters

`bitmap`	contains pixels copied to Canvas
`x`	offset into Canvas writable pixels in x; may be negative
`y`	offset into Canvas writable pixels in y; may be negative

Return Value

true if pixels were written to Canvas

Example

Draw to ever smaller clips; then restore drawing to full canvas. Note that the second clipRect is not permitted to enlarge Clip.

Each Clip uses the current Matrix for its coordinates.

Example

While clipRect is given the same rectangle twice, Matrix makes the second clipRect draw at half the size of the first.

Return Value

depth of saved stack

Example

The black square is translated 50 pixels down and to the right. Restoring Canvas state removes translate() from Canvas stack; the red square is not translated, and is drawn at the origin.

Example

Return Value

depth of save state stack

Example

Example Output

depth = 1
depth = 2
depth = 1

Parameters

saveCount depth of state stack to restore

Example

Example Output

depth = 1
depth = 3
depth = 1

Parameters

`bounds`	hint to limit the size of the layer; may be nullptr
`paint`	graphics state for layer; may be nullptr

Return Value

depth of saved stack

Example

Rectangles are blurred by Image_Filter when restore() draws Layer to main Canvas.

Parameters

`bounds`	hint to limit the size of layer; may be nullptr
`paint`	graphics state for layer; may be nullptr

Return Value

depth of saved stack

Example

Rectangles are blurred by Image_Filter when restore() draws Layer to main Canvas. The red rectangle is clipped; it does not fully fit on Layer. Image_Filter blurs past edge of Layer so red rectangle is blurred on all sides.

Parameters

`bounds`	hint to limit the size of layer; may be nullptr
`paint`	graphics state for layer; may be nullptr

Return Value

depth of saved stack

Example

Parameters

`bounds`	hint to limit the size of layer; may be nullptr
`alpha`	opacity of layer

Return Value

depth of saved stack

Example

Constants

Const	Value	Description
`SkCanvas::kPreserveLCDText_SaveLayerFlag`	2	Creates Layer for LCD text. Flag is ignored if Layer Paint contains Image_Filter or Color_Filter.
`SkCanvas::kInitWithPrevious_SaveLayerFlag`	4	Initializes Layer with the contents of the previous Layer.

Example

Canvas Layer captures red and blue circles scaled up by four. scalePaint blends Layer back with transparency.

Type	Member	Description
const SkRect*	`fBounds`	fBounds is used as a hint to limit the size of Layer; may be nullptr. fBounds suggests but does not define Layer size. To clip drawing to a specific rectangle, use clipRect.
const SkPaint*	`fPaint`	fPaint modifies how Layer overlays the prior Layer; may be nullptr. Color_Alpha, Blend_Mode, Color_Filter, Draw_Looper, Image_Filter, and Mask_Filter affect Layer draw.
const SkImageFilter*	`fBackdrop`	fBackdrop applies Image_Filter to the prior Layer when copying to the Layer; may be nullptr. Use kInitWithPrevious_SaveLayerFlag to copy the prior Layer without an Image_Filter.
const SkImage*	`fClipMask`	restore() clips Layer by the Color_Alpha channel of fClipMask when Layer is copied to Device. fClipMask may be nullptr. .
const SkMatrix*	`fClipMatrix`	fClipMatrix transforms fClipMask before it clips Layer. If fClipMask describes a translucent gradient, it may be scaled and rotated without introducing artifacts. fClipMatrix may be nullptr.
SaveLayerFlags	`fSaveLayerFlags`	fSaveLayerFlags are used to create Layer without transparency, create Layer for LCD text, and to create Layer with the contents of the previous Layer.

Example

Canvas Layer captures a red Anti_Aliased circle and a blue Aliased circle scaled up by four. After drawing another red circle without scaling on top, the Layer is transferred to the main canvas.

SaveLayerRec()

Sets fBounds, fPaint, and fBackdrop to nullptr. Clears fSaveLayerFlags.

Return Value

empty SaveLayerRec

Example

Example Output

rec1 == rec2

Parameters

`bounds`	layer dimensions; may be nullptr
`paint`	applied to layer when overlaying prior layer; may be nullptr
`saveLayerFlags`	SaveLayerRec options to modify layer

Return Value

SaveLayerRec with empty fBackdrop

Example

Example Output

rec1 == rec2

Parameters

`bounds`	layer dimensions; may be nullptr
`paint`	applied to layer when overlaying prior layer;

may be nullptr

Parameters

`backdrop`	prior layer copied with SkImageFilter; may be nullptr
`saveLayerFlags`	SaveLayerRec options to modify layer

Return Value

SaveLayerRec fully specified

Example

Example Output

rec1 == rec2

Parameters

layerRec layer state

Return Value

depth of save state stack before this call was made.

Example

The example draws an image, and saves it into a Layer with kInitWithPrevious_SaveLayerFlag. Next it punches a hole in Layer and restore with SkBlendMode::kPlus. Where Layer was cleared, the original image will draw unchanged. Outside of the circle the mandrill is brightened.

Parameters

`dx`	distance to translate on x-axis
`dy`	distance to translate on y-axis

Example

scale() followed by translate() produces different results from translate() followed by scale().

The blue stroke follows translate of (50, 50); a black fill follows scale of (2, 1/2.f). After restoring the clip, which resets Matrix, a red frame follows the same scale of (2, 1/2.f); a gray fill follows translate of (50, 50).

Parameters

`sx`	amount to scale on x-axis
`sy`	amount to scale on y-axis

Example

Parameters

degrees amount to rotate, in degrees

Example

Draw clock hands at time 5:10. The hour hand and minute hand point up and are rotated clockwise.

Parameters

`degrees`	amount to rotate, in degrees
`px`	x-axis value of the point to rotate about
`py`	y-axis value of the point to rotate about

Example

Parameters

`sx`	amount to skew on x-axis
`sy`	amount to skew on y-axis

Example

Black text mimics an oblique text style by using a negative skew on x-axis that shifts the geometry to the right as the y-axis values decrease. Red text uses a positive skew on y-axis to shift the geometry down as the x-axis values increase. Blue text combines sx and sy skew to rotate and scale.

Parameters

matrix matrix to premultiply with existing SkMatrix

Example

Parameters

matrix matrix to copy, replacing existing SkMatrix

Example

Return Value

SkMatrix in SkCanvas

Example

Example Output

isIdentity true

Example

Draw a red circle with an Aliased clip and an Anti_Aliased clip. Use an image filter to zoom into the pixels drawn. The edge of the Aliased clip fully draws pixels in the red circle. The edge of the Anti_Aliased clip partially draws pixels in the red circle.

void clipRect(const SkRect& rect, SkClipOp op, bool doAntiAlias)

Replaces clip with the intersection or difference of clip and rect, with an aliased or anti-aliased clip edge. rect is transformed by SkMatrix before it is combined with clip.

Parameters

`rect`	SkRect to combine with clip
`op`	SkClipOp to apply to clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

Parameters

`rect`	SkRect to combine with clip
`op`	SkClipOp to apply to clip

Example

Parameters

`rect`	SkRect to combine with clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

A circle drawn in pieces looks uniform when drawn Aliased. The same circle pieces blend with pixels more than once when Anti_Aliased, visible as a thin pair of lines through the right circle.

Parameters

`rrect`	SkRRect to combine with clip
`op`	SkClipOp to apply to clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

Parameters

`rrect`	SkRRect to combine with clip
`op`	SkClipOp to apply to clip

Example

Parameters

`rrect`	SkRRect to combine with clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

Parameters

`path`	SkPath to combine with clip
`op`	SkClipOp to apply to clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

Top figure uses SkPath::kInverseWinding_FillType and SkClipOp::kDifference; area outside clip is subtracted from circle.

Bottom figure uses SkPath::kWinding_FillType and SkClipOp::kIntersect; area inside clip is intersected with circle.

Parameters

`path`	SkPath to combine with clip
`op`	SkClipOp to apply to clip

Example

Overlapping Rects form a clip. When clip Path_Fill_Type is set to SkPath::kWinding_FillType, the overlap is included. Set to SkPath::kEvenOdd_FillType, the overlap is excluded and forms a hole.

Parameters

`path`	SkPath to combine with clip
`doAntiAlias`	true if clip is to be anti-aliased

Example

Clip loops over itself covering its center twice. When clip Path_Fill_Type is set to SkPath::kWinding_FillType, the overlap is included. Set to SkPath::kEvenOdd_FillType, the overlap is excluded and forms a hole.

Parameters

`deviceRgn`	SkRegion to combine with clip
`op`	SkClipOp to apply to clip

Example

region is unaffected by canvas rotation; iRect is affected by canvas rotation. Both clips are Aliased; this is not noticeable on Region clip because it aligns to pixel boundaries.

Parameters

rect SkRect to compare with clip

Return Value

true if rect, transformed by SkMatrix, does not intersect clip

Example

Example Output

quickReject true
quickReject false

Parameters

path SkPath to compare with clip

Return Value

true if path, transformed by SkMatrix, does not intersect clip

Example

Example Output

quickReject true
quickReject false

Return Value

bounds of clip in local coordinates

Example

Initial bounds is device bounds outset by 1 on all sides. Clipped bounds is clipPath bounds outset by 1 on all sides. Scaling the canvas by two on both axes scales the local bounds by 1/2 on both axes.

Example Output

left:-1  top:-1  right:257  bottom:257
left:29  top:129  right:121  bottom:231
left:14.5  top:64.5  right:60.5  bottom:115.5

Parameters

bounds SkRect of clip in local coordinates

Return Value

true if clip bounds is not empty

Example

Example Output

local bounds empty = false
local bounds empty = true

Return Value

bounds of clip in SkBaseDevice coordinates

Example

Initial bounds is device bounds, not outset. Clipped bounds is clipPath bounds, not outset. Scaling the canvas by 1/2 on both axes scales the device bounds by 1/2 on both axes.

Example Output

left:0  top:0  right:256  bottom:256
left:30  top:130  right:120  bottom:230
left:15  top:65  right:60  bottom:115

Parameters

bounds SkRect of clip in device coordinates

Return Value

true if clip bounds is not empty

Example

Example Output

device bounds empty = false
device bounds empty = true

Parameters

`color`	unpremultiplied ARGB
`mode`	SkBlendMode used to combine source color and destination

Example

Parameters

color unpremultiplied ARGB

Example

Parameters

paint graphics state used to fill SkCanvas

Example

Constants

Const	Value	Description
`SkCanvas::kPoints_PointMode`	0	draw each point separately
`SkCanvas::kLines_PointMode`	1	draw each pair of points as a line segment
`SkCanvas::kPolygon_PointMode`	2	draw the array of points as a open polygon

Example

The upper left corner shows three squares when drawn as points. The upper right corner shows one line; when drawn as lines, two points are required per line. The lower right corner shows two lines; when draw as polygon, no miter is drawn at the corner. The lower left corner shows two lines with a miter when path contains polygon.

Parameters

`mode`	whether pts draws points or lines
`count`	number of points in the array
`pts`	array of points to draw
`paint`	stroke, blend, color, and so on, used to draw

Example

The first column draws points.

The second column draws points as lines.

The third column draws points as a polygon.

The fourth column draws points as a polygonal path.

The first row uses a round cap and round join.

The second row uses a square cap and a miter join.

The third row uses a butt cap and a bevel join.

The transparent color makes multiple line draws visible; the path is drawn all at once.

Parameters

`x`	left edge of circle or square
`y`	top edge of circle or square
`paint`	stroke, blend, color, and so on, used to draw

Example

Parameters

`p`	top-left edge of circle or square
`paint`	stroke, blend, color, and so on, used to draw

Example

Parameters

`x0`	start of line segment on x-axis
`y0`	start of line segment on y-axis
`x1`	end of line segment on x-axis
`y1`	end of line segment on y-axis
`paint`	stroke, blend, color, and so on, used to draw

Example

Parameters

`p0`	start of line segment
`p1`	end of line segment
`paint`	stroke, blend, color, and so on, used to draw

Example

Parameters

`rect`	rectangle to draw
`paint`	stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`rect`	rectangle to draw
`paint`	stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`region`	region to draw
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`oval`	SkRect bounds of oval
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`rrect`	SkRRect with up to eight corner radii to draw
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`outer`	SkRRect outer bounds to draw
`inner`	SkRRect inner bounds to draw
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Outer Rect has no corner radii, but stroke join is rounded. Inner Round_Rect has corner radii; outset stroke increases radii of corners. Stroke join does not affect inner Round_Rect since it has no sharp corners.

Parameters

`cx`	circle center on the x-axis
`cy`	circle center on the y-axis
`radius`	half the diameter of circle
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`center`	circle center
`radius`	half the diameter of circle
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`oval`	SkRect bounds of oval containing arc to draw
`startAngle`	angle in degrees where arc begins
`sweepAngle`	sweep angle in degrees; positive is clockwise
`useCenter`	if true, include the center of the oval
`paint`	SkPaint stroke or fill, blend, color, and so on, used to draw

Example

Parameters

`rect`	SkRect bounds of SkRRect to draw
`rx`	axis length on x-axis of oval describing rounded corners
`ry`	axis length on y-axis of oval describing rounded corners
`paint`	stroke, blend, color, and so on, used to draw

Example

Top row has a zero radius a generates a rectangle. Second row radii sum to less than sides. Third row radii sum equals sides. Fourth row radii sum exceeds sides; radii are scaled to fit.

Parameters

`path`	SkPath to draw
`paint`	stroke, blend, color, and so on, used to draw

Example

Top rows draw stroked path with combinations of joins and caps. The open contour is affected by caps; the closed contour is affected by joins. Bottom row draws fill the same for open and closed contour. First bottom column shows winding fills overlap. Second bottom column shows even odd fills exclude overlap. Third bottom column shows inverse winding fills area outside both contours.

Parameters

`image`	uncompressed rectangular map of pixels
`left`	left side of image
`top`	top side of image
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Example

Parameters

`image`	uncompressed rectangular map of pixels
`left`	left side of image
`top`	pop side of image
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Example

Constants

Const	Value	Description
`SkCanvas::kStrict_SrcRectConstraint`	0	Requires Image_Filter to respect source Rect, sampling only inside of its bounds, possibly with a performance penalty.
`SkCanvas::kFast_SrcRectConstraint`	1	Permits Image_Filter to sample outside of source Rect by half the width of Image_Filter, permitting it to run faster but with error at the image edges.

Example

redBorder contains a black and white checkerboard bordered by red. redBorder is drawn scaled by 16 on the left. The middle and right bitmaps are filtered checkerboards. Drawing the checkerboard with kStrict_SrcRectConstraint shows only a blur of black and white. Drawing the checkerboard with kFast_SrcRectConstraint allows red to bleed in the corners.

Parameters

`image`	SkImage containing pixels, dimensions, and format
`src`	source SkRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within src or draw faster

Example

The left bitmap draws with Paint default kNone_SkFilterQuality, and stays within its bounds; there is no bleeding with kFast_SrcRectConstraint. the middle and right bitmaps draw with kLow_SkFilterQuality; with kStrict_SrcRectConstraint, the filter remains within the checkerboard, and with kFast_SrcRectConstraint red bleeds on the edges.

Parameters

`image`	SkImage containing pixels, dimensions, and format
`isrc`	source SkIRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within isrc or draw faster

Example

Parameters

`image`	SkImage containing pixels, dimensions, and format
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Example

Parameters

`image`	SkImage containing pixels, dimensions, and format
`src`	source SkRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within src or draw faster

Example

Canvas scales and translates; transformation from src to dst also scales. The two matrices are concatenated to create the final transformation.

Parameters

`image`	SkImage containing pixels, dimensions, and format
`isrc`	source SkIRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within image or draw faster

Example

Parameters

`image`	SkImage containing pixels, dimensions, and format
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Example

Parameters

`image`	Image containing pixels, dimensions, and format
`center`	IRect edge of image corners and sides
`dst`	destination Rect of image to draw to
`paint`	Paint containing Blend_Mode, Color_Filter, Image_Filter, and so on; or nullptr

Example

The leftmost image is smaller than center; only corners are drawn, all scaled to fit. The second image equals the size of center; only corners are drawn without scaling. The remaining images are larger than center. All corners draw without scaling. The sides and center are scaled if needed to take up the remaining space.

Parameters

`image`	Image containing pixels, dimensions, and format
`center`	IRect edge of image corners and sides
`dst`	destination Rect of image to draw to
`paint`	Paint containing Blend_Mode, Color_Filter, Image_Filter, and so on; or nullptr

Example

The two leftmost images has four corners and sides to the left and right of center. The leftmost image scales the width of corners proportionately to fit. The third and fourth image corners are not scaled; the sides and center are scaled to fill the remaining space. The rightmost image has four corners scaled vertically to fit, and uses sides above and below center to fill the remaining space.

Parameters

`bitmap`	SkBitmap containing pixels, dimensions, and format
`left`	left side of bitmap
`top`	top side of bitmap
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Example

Parameters

`bitmap`	SkBitmap containing pixels, dimensions, and format
`src`	source SkRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within src or draw faster

Example

Parameters

`bitmap`	SkBitmap containing pixels, dimensions, and format
`isrc`	source SkIRect of image to draw from
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint sample strictly within isrc, or draw faster

Example

Parameters

`bitmap`	SkBitmap containing pixels, dimensions, and format
`dst`	destination SkRect of image to draw to
`paint`	SkPaint containing SkBlendMode, SkColorFilter, SkImageFilter,

and so on; or nullptr

Parameters

constraint filter strictly within bitmap or draw faster

Example

Parameters

`bitmap`	Bitmap containing pixels, dimensions, and format
`center`	IRect edge of image corners and sides
`dst`	destination Rect of image to draw to
`paint`	Paint containing Blend_Mode, Color_Filter, Image_Filter, and so on; or nullptr

Example

The two leftmost bitmap draws has four corners and sides to the left and right of center. The leftmost bitmap draw scales the width of corners proportionately to fit. The third and fourth draw corners are not scaled; the sides and center are scaled to fill the remaining space. The rightmost bitmap draw has four corners scaled vertically to fit, and uses sides above and below center to fill the remaining space.

Constants

Const	Value	Description
`SkCanvas::Lattice::kDefault`	0	draws Bitmap into lattice rectangle
`SkCanvas::Lattice::kTransparent`	1	skips lattice rectangle by making it transparent
`SkCanvas::Lattice::kFixedColor`	2	draws one of fColors into lattice rectangle

Type	Member	Description
const int*	`fXDivs`	Array of x-axis values that divide the bitmap vertically. Array entries must be unique, increasing, greater than or equal to fBounds left edge, and less than fBounds right edge. Set the first element to fBounds left to collapse the left column of fixed grid entries.
const int*	`fYDivs`	Array of y-axis values that divide the bitmap horizontally. Array entries must be unique, increasing, greater than or equal to fBounds top edge, and less than fBounds bottom edge. Set the first element to fBounds top to collapse the top row of fixed grid entries.
const RectType*	`fRectTypes`	Optional array of fill types, one per rectangular grid entry: array length must be `(fXCount + 1) * (fYCount + 1)`. Each RectType is one of: kDefault, kTransparent, kFixedColor. Array entries correspond to the rectangular grid entries, ascending left to right and then top to bottom.
int	`fXCount`	Number of entries in fXDivs array; one less than the number of horizontal divisions.
int	`fYCount`	Number of entries in fYDivs array; one less than the number of vertical divisions.
const SkIRect*	`fBounds`	Optional subset IRect source to draw from. If nullptr, source bounds is dimensions of Bitmap or Image.
const SkColor*	`fColors`	Optional array of colors, one per rectangular grid entry. Array length must be `(fXCount + 1) * (fYCount + 1)`. Array entries correspond to the rectangular grid entries, ascending left to right, then top to bottom.

void drawBitmapLattice(const SkBitmap& bitmap, const Lattice& lattice, const SkRect& dst,
                       const SkPaint* paint = nullptr)

Draws Bitmap bitmap stretched proportionally to fit into Rect dst.

Lattice lattice divides bitmap into a rectangular grid. Each intersection of an even-numbered row and column is fixed; like the corners of drawBitmapNine, fixed lattice elements never scale larger than their initial size and shrink proportionately when all fixed elements exceed the bitmap dimension. All other grid elements scale to fill the available space, if any.

Additionally transform draw using Clip, Matrix, and optional Paint paint. If Paint paint is supplied, apply Color_Filter, Color_Alpha, Image_Filter, Blend_Mode, and Draw_Looper. If bitmap is kAlpha_8_SkColorType, apply Shader. If paint contains Mask_Filter, generate mask from bitmap bounds. If paint Filter_Quality set to kNone_SkFilterQuality, disable pixel filtering. For all other values of paint Filter_Quality, use kLow_SkFilterQuality to filter pixels. Any SkMaskFilter on paint is ignored as is paint Anti_Aliasing state. If generated mask extends beyond bitmap bounds, replicate bitmap edge colors, just as Shader made from SkShader::MakeBitmapShader with SkShader::kClamp_TileMode set replicates the bitmap edge color when it samples outside of its bounds.

Parameters

`bitmap`	Bitmap containing pixels, dimensions, and format
`lattice`	division of bitmap into fixed and variable rectangles
`dst`	destination Rect of image to draw to
`paint`	Paint containing Blend_Mode, Color_Filter, Image_Filter, and so on; or nullptr

Example

The two leftmost bitmap draws has four corners and sides to the left and right of center. The leftmost bitmap draw scales the width of corners proportionately to fit. The third and fourth draw corners are not scaled; the sides are scaled to fill the remaining space; the center is transparent. The rightmost bitmap draw has four corners scaled vertically to fit, and uses sides above and below center to fill the remaining space.

Parameters

`image`	Image containing pixels, dimensions, and format
`lattice`	division of bitmap into fixed and variable rectangles
`dst`	destination Rect of image to draw to
`paint`	Paint containing Blend_Mode, Color_Filter, Image_Filter, and so on; or nullptr

Example

The leftmost image is smaller than center; only corners are drawn, all scaled to fit. The second image equals the size of center; only corners are drawn without scaling. The remaining images are larger than center. All corners draw without scaling. The sides are scaled if needed to take up the remaining space; the center is transparent.

Parameters

`text`	character code points or glyphs drawn
`byteLength`	byte length of text array
`x`	start of text on x-axis
`y`	start of text on y-axis
`paint`	text size, blend, color, and so on, used to draw

Example

The same text is drawn varying Paint_Text_Size and varying Matrix.

Parameters

string character code points or glyphs drawn,

ending with a char value of zero

Parameters

`x`	start of string on x-axis
`y`	start of string on y-axis
`paint`	text size, blend, color, and so on, used to draw

Example

Parameters

string character code points or glyphs drawn,

ending with a char value of zero

Parameters

`x`	start of string on x-axis
`y`	start of string on y-axis
`paint`	text size, blend, color, and so on, used to draw

Example

Parameters

`text`	character code points or glyphs drawn
`byteLength`	byte length of text array
`pos`	array of glyph origins
`paint`	text size, blend, color, and so on, used to draw

Example

Parameters

`text`	character code points or glyphs drawn
`byteLength`	byte length of text array
`xpos`	array of x-axis positions, used to position each glyph
`constY`	shared y-axis value for all of x-axis positions
`paint`	text size, blend, color, and so on, used to draw

Example

Parameters

`text`	character code points or glyphs drawn
`byteLength`	byte length of text array
`xform`	SkRSXform rotates, scales, and translates each glyph individually
`cullRect`	SkRect bounds of text for efficient clipping; or nullptr
`paint`	text size, blend, color, and so on, used to draw

Example

Parameters

`blob`	Glyphs, positions, and their paints' text size, typeface, and so on
`x`	horizontal offset applied to blob
`y`	vertical offset applied to blob
`paint`	blend, color, stroking, and so on, used to draw

Example

Parameters

`blob`	Glyphs, positions, and their paints' text size, typeface, and so on
`x`	horizontal offset applied to blob
`y`	vertical offset applied to blob
`paint`	blend, color, stroking, and so on, used to draw

Example

Paint attributes related to text, like text size, have no effect on paint passed to drawTextBlob.

Parameters

picture recorded drawing commands to play

Example

Parameters

picture recorded drawing commands to play

Example

Parameters

`picture`	recorded drawing commands to play
`matrix`	SkMatrix to rotate, scale, translate, and so on; may be nullptr
`paint`	SkPaint to apply transparency, filtering, and so on; may be nullptr

Example

Parameters

`picture`	recorded drawing commands to play
`matrix`	SkMatrix to rotate, scale, translate, and so on; may be nullptr
`paint`	SkPaint to apply transparency, filtering, and so on; may be nullptr

Example

Parameters

`vertices`	triangle mesh to draw
`mode`	combines vertices colors with SkShader, if both are present
`paint`	specifies the SkShader, used as SkVertices texture; may be nullptr

Example

Parameters

`vertices`	triangle mesh to draw
`mode`	combines vertices colors with SkShader, if both are present
`paint`	specifies the SkShader, used as SkVertices texture, may be nullptr

Example

Parameters

`vertices`	triangle mesh to draw
`bones`	bone matrix data
`boneCount`	number of bone matrices
`mode`	combines vertices colors with SkShader, if both are present
`paint`	specifies the SkShader, used as SkVertices texture, may be nullptr

Parameters

`vertices`	triangle mesh to draw
`bones`	bone matrix data
`boneCount`	number of bone matrices
`mode`	combines vertices colors with SkShader, if both are present
`paint`	specifies the SkShader, used as SkVertices texture, may be nullptr

Parameters

`cubics`	SkPath cubic array, sharing common points
`colors`	color array, one for each corner
`texCoords`	SkPoint array of texture coordinates, mapping SkShader to corners;

may be nullptr

Parameters

`mode`	SkBlendMode for colors, and for SkShader if paint has one
`paint`	SkShader, SkColorFilter, SkBlendMode, used to draw

Example

Parameters

`cubics`	SkPath cubic array, sharing common points
`colors`	color array, one for each corner
`texCoords`	SkPoint array of texture coordinates, mapping SkShader to corners;

may be nullptr

Parameters

paint SkShader, SkColorFilter, SkBlendMode, used to draw

Example

Parameters

`atlas`	SkImage containing sprites
`xform`	SkRSXform mappings for sprites in atlas
`tex`	SkRect locations of sprites in atlas
`colors`	one per sprite, blended with sprite using SkBlendMode; may be nullptr
`count`	number of sprites to draw
`mode`	SkBlendMode combining colors and sprites
`cullRect`	bounds of transformed sprites for efficient clipping; may be nullptr
`paint`	SkColorFilter, SkImageFilter, SkBlendMode, and so on; may be nullptr

Example

Parameters

`atlas`	SkImage containing sprites
`xform`	SkRSXform mappings for sprites in atlas
`tex`	SkRect locations of sprites in atlas
`colors`	one per sprite, blended with sprite using SkBlendMode; may be nullptr
`count`	number of sprites to draw
`mode`	SkBlendMode combining colors and sprites
`cullRect`	bounds of transformed sprites for efficient clipping; may be nullptr
`paint`	SkColorFilter, SkImageFilter, SkBlendMode, and so on; may be nullptr

Example

Parameters

`atlas`	SkImage containing sprites
`xform`	SkRSXform mappings for sprites in atlas
`tex`	SkRect locations of sprites in atlas
`count`	number of sprites to draw
`cullRect`	bounds of transformed sprites for efficient clipping; may be nullptr
`paint`	SkColorFilter, SkImageFilter, SkBlendMode, and so on; may be nullptr

Example

Parameters

`atlas`	SkImage containing sprites
`xform`	SkRSXform mappings for sprites in atlas
`tex`	SkRect locations of sprites in atlas
`count`	number of sprites to draw
`cullRect`	bounds of transformed sprites for efficient clipping; may be nullptr
`paint`	SkColorFilter, SkImageFilter, SkBlendMode, and so on; may be nullptr

Example

Parameters

`drawable`	custom struct encapsulating drawing commands
`matrix`	transformation applied to drawing; may be nullptr

Example

Parameters

`drawable`	custom struct encapsulating drawing commands
`x`	offset into SkCanvas writable pixels on x-axis
`y`	offset into SkCanvas writable pixels on y-axis

Example

Parameters

`rect`	SkRect extent of canvas to annotate
`key`	string used for lookup
`value`	data holding value stored in annotation

Example

Parameters

`rect`	SkRect extent of canvas to annotate
`key`	string used for lookup
`value`	data holding value stored in annotation

Example

Return Value

true if clip is empty

Example

Example Output

clip is not empty
clip is empty

Return Value

true if clip is SkRect and not empty

Example

Example Output

clip is rect
clip is not rect

402 KiB Raw Blame History

SkCanvas Reference

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