Documentation ¶
Index ¶
- Variables
- func Color2Hex(c color.Color) string
- func GetImageType(bytes []byte) (ext string, mimetype string, decoder func(r io.Reader) (image.Image, error), ...)
- func Image2RGBA(img image.Image) *image.RGBA
- func LoadFontFace(path string, points float64) (font.Face, error)
- func Radians(degrees float64) float64
- type Align
- type Context
- func (dc *Context) AsMask() *image.Alpha
- func (dc *Context) Clear()
- func (dc *Context) ClearPath()
- func (dc *Context) Clip()
- func (dc *Context) ClipPreserve()
- func (dc *Context) ClosePath()
- func (dc *Context) CubicTo(x1, y1, x2, y2, x3, y3 float64)
- func (dc *Context) DrawArc(x, y, r, angle1, angle2 float64)
- func (dc *Context) DrawCircle(x, y, r float64)
- func (dc *Context) DrawEllipse(x, y, rx, ry float64)
- func (dc *Context) DrawEllipticalArc(x, y, rx, ry, angle1, angle2 float64)
- func (dc *Context) DrawImage(im image.Image, x, y int)
- func (dc *Context) DrawImageAnchored(im image.Image, x, y int, ax, ay float64)
- func (dc *Context) DrawLine(x1, y1, x2, y2 float64)
- func (dc *Context) DrawPoint(x, y, r float64)
- func (dc *Context) DrawRectangle(x, y, w, h float64)
- func (dc *Context) DrawRegularPolygon(n int, x, y, r, rotation float64)
- func (dc *Context) DrawRoundedRectangle(x, y, w, h, r float64)
- func (dc *Context) DrawString(s string, x, y float64)
- func (dc *Context) DrawStringAnchored(s string, x, y, ax, ay float64)
- func (dc *Context) DrawStringWrapped(s string, x, y, ax, ay, width, lineSpacing float64, align Align)
- func (dc *Context) Fill()
- func (dc *Context) FillPreserve()
- func (dc *Context) FontHeight() float64
- func (dc *Context) GetCurrentPoint() (Point, bool)
- func (dc *Context) Height() int
- func (dc *Context) Identity()
- func (dc *Context) Image() image.Image
- func (dc *Context) InvertMask()
- func (dc *Context) InvertY()
- func (dc *Context) LineTo(x, y float64)
- func (dc *Context) LoadFontFace(path string, points float64) error
- func (dc *Context) MeasureMultilineString(s string, lineSpacing float64) (width, height float64)
- func (dc *Context) MeasureString(s string) (w, h float64)
- func (dc *Context) MoveTo(x, y float64)
- func (dc *Context) NewSubPath()
- func (dc *Context) Pop()
- func (dc *Context) Push()
- func (dc *Context) QuadraticTo(x1, y1, x2, y2 float64)
- func (dc *Context) ResetClip()
- func (dc *Context) Rotate(angle float64)
- func (dc *Context) RotateAbout(angle, x, y float64)
- func (dc *Context) Scale(x, y float64)
- func (dc *Context) ScaleAbout(sx, sy, x, y float64)
- func (dc *Context) SetColor(c color.Color)
- func (dc *Context) SetDash(dashes ...float64)
- func (dc *Context) SetDashOffset(offset float64)
- func (dc *Context) SetFillRule(fillRule FillRule)
- func (dc *Context) SetFillRuleEvenOdd()
- func (dc *Context) SetFillRuleWinding()
- func (dc *Context) SetFontFace(fontFace font.Face)
- func (dc *Context) SetLineCap(lineCap LineCap)
- func (dc *Context) SetLineCapButt()
- func (dc *Context) SetLineCapRound()
- func (dc *Context) SetLineCapSquare()
- func (dc *Context) SetLineJoin(lineJoin LineJoin)
- func (dc *Context) SetLineJoinBevel()
- func (dc *Context) SetLineJoinRound()
- func (dc *Context) SetLineWidth(lineWidth float64)
- func (dc *Context) SetMask(mask *image.Alpha) error
- func (dc *Context) SetPixel(x, y int)
- func (dc *Context) SetRGB(r, g, b float64)
- func (dc *Context) SetRGB255(r, g, b int)
- func (dc *Context) SetRGBA(r, g, b, a float64)
- func (dc *Context) SetRGBA255(r, g, b, a int)
- func (dc *Context) SetStrokeStyle(pattern Pattern)
- func (dc *Context) Shear(x, y float64)
- func (dc *Context) ShearAbout(sx, sy, x, y float64)
- func (dc *Context) Stroke()
- func (dc *Context) StrokePreserve()
- func (dc *Context) TransformPoint(x, y float64) (tx, ty float64)
- func (dc *Context) Translate(x, y float64)
- func (dc *Context) Width() int
- func (dc *Context) WordWrap(s string, w float64) []string
- type FillRule
- type FlipType
- type Image
- func Canvas(width, height int, fillColor ...color.Color) *Image
- func Load(source interface{}) *Image
- func LoadFromBase64(base64Str string) (i *Image)
- func LoadFromFile(file *os.File) (i *Image)
- func LoadFromImage(img image.Image) (i *Image)
- func LoadFromImgo(i *Image) *Image
- func LoadFromPath(path string) (i *Image)
- func LoadFromUrl(url string) (i *Image)
- func (i *Image) Blur(ksize int) *Image
- func (i *Image) BorderRadius(radius float64) *Image
- func (i Image) Bounds() image.Rectangle
- func (i *Image) Circle(x, y, radius int, c color.Color) *Image
- func (i *Image) Crop(x, y, width, height int) *Image
- func (i *Image) Ellipse(x, y, width, height int, c color.Color) *Image
- func (i Image) Extension() string
- func (i Image) Filesize() int64
- func (i *Image) Flip(flipType FlipType) *Image
- func (i *Image) GaussianBlur(ksize int, sigma float64) *Image
- func (i *Image) Grayscale() *Image
- func (i Image) Height() int
- func (i Image) HttpHandler(w http.ResponseWriter, r *http.Request)
- func (i *Image) Insert(source interface{}, x, y int) *Image
- func (i *Image) Line(x1, y1, x2, y2 int, c color.Color, width ...int) *Image
- func (i *Image) MainColor() (res color.RGBA)
- func (i Image) Mimetype() string
- func (i *Image) Mosaic(size, x1, y1, x2, y2 int) *Image
- func (i Image) PickColor(x, y int) (res color.RGBA)
- func (i *Image) Pixel(x, y int, c color.Color) *Image
- func (i *Image) Pixelate(size int) *Image
- func (i *Image) Rectangle(x, y, width, height int, c color.Color) *Image
- func (i *Image) Resize(width, height int) *Image
- func (i *Image) Rotate(angle int) *Image
- func (i *Image) Save(path string, quality ...int) *Image
- func (i Image) String() string
- func (i *Image) Text(label string, x, y int, fontPath string, fontColor color.Color, ...) *Image
- func (i *Image) TextWordWrap(label string, x, y float64, fontPath string, fontColor color.Color, ...) *Image
- func (i *Image) Thumbnail(width, height int) *Image
- func (i Image) ToBase64() string
- func (i Image) ToImage() image.Image
- func (i Image) Width() int
- type ImageManager
- type LineCap
- type LineJoin
- type Matrix
- func (a Matrix) Multiply(b Matrix) Matrix
- func (a Matrix) Rotate(angle float64) Matrix
- func (a Matrix) Scale(x, y float64) Matrix
- func (a Matrix) Shear(x, y float64) Matrix
- func (a Matrix) TransformPoint(x, y float64) (tx, ty float64)
- func (a Matrix) TransformVector(x, y float64) (tx, ty float64)
- func (a Matrix) Translate(x, y float64) Matrix
- type Pattern
- type Point
- type Radius
- type RepeatOp
Constants ¶
This section is empty.
Variables ¶
var ( ErrSourceImageIsNil = errors.New("source image is nil") ErrSourceNotSupport = errors.New("source not support") ErrSourceStringIsEmpty = errors.New("source string is empty") ErrSourceImageNotSupport = errors.New("source image not support") ErrSaveImageFormatNotSupport = errors.New("save image format not support") )
Functions ¶
func GetImageType ¶
func GetImageType(bytes []byte) (ext string, mimetype string, decoder func(r io.Reader) (image.Image, error), err error)
GetImageType returns the extension, mimetype and corresponding decoder function of the image. It judges the image by its first few bytes called magic number.
func Image2RGBA ¶
Image2RGBA converts an image to RGBA.
func LoadFontFace ¶
LoadFontFace is a helper function to load the specified font file with the specified point size. Note that the returned `font.Face` objects are not thread safe and cannot be used in parallel across goroutines. You can usually just use the Context.LoadFontFace function instead of this package-level function.
Types ¶
type Context ¶
type Context struct {
// contains filtered or unexported fields
}
func NewContext ¶
NewContext creates a new image.RGBA with the specified width and height and prepares a context for rendering onto that image.
func NewContextForImage ¶
NewContextForImage copies the specified image into a new image.RGBA and prepares a context for rendering onto that image.
func NewContextForRGBA ¶
NewContextForRGBA prepares a context for rendering onto the specified image. No copy is made.
func (*Context) AsMask ¶
AsMask returns an *image.Alpha representing the alpha channel of this context. This can be useful for advanced clipping operations where you first render the mask geometry and then use it as a mask.
func (*Context) Clear ¶
func (dc *Context) Clear()
Clear fills the entire image with the current color.
func (*Context) ClearPath ¶
func (dc *Context) ClearPath()
ClearPath clears the current path. There is no current point after this operation.
func (*Context) Clip ¶
func (dc *Context) Clip()
Clip updates the clipping region by intersecting the current clipping region with the current path as it would be filled by dc.Fill(). The path is cleared after this operation.
func (*Context) ClipPreserve ¶
func (dc *Context) ClipPreserve()
ClipPreserve updates the clipping region by intersecting the current clipping region with the current path as it would be filled by dc.Fill(). The path is preserved after this operation.
func (*Context) ClosePath ¶
func (dc *Context) ClosePath()
ClosePath adds a line segment from the current point to the beginning of the current subpath. If there is no current point, this is a no-op.
func (*Context) CubicTo ¶
CubicTo adds a cubic bezier curve to the current path starting at the current point. If there is no current point, it first performs MoveTo(x1, y1). Because freetype/raster does not support cubic beziers, this is emulated with many small line segments.
func (*Context) DrawCircle ¶
func (*Context) DrawEllipse ¶
func (*Context) DrawEllipticalArc ¶
func (*Context) DrawImageAnchored ¶
DrawImageAnchored draws the specified image at the specified anchor point. The anchor point is x - w * ax, y - h * ay, where w, h is the size of the image. Use ax=0.5, ay=0.5 to center the image at the specified point.
func (*Context) DrawPoint ¶
DrawPoint is like DrawCircle but ensures that a circle of the specified size is drawn regardless of the current transformation matrix. The position is still transformed, but not the shape of the point.
func (*Context) DrawRectangle ¶
func (*Context) DrawRegularPolygon ¶
func (*Context) DrawRoundedRectangle ¶
func (*Context) DrawString ¶
DrawString draws the specified text at the specified point.
func (*Context) DrawStringAnchored ¶
DrawStringAnchored draws the specified text at the specified anchor point. The anchor point is x - w * ax, y - h * ay, where w, h is the size of the text. Use ax=0.5, ay=0.5 to center the text at the specified point.
func (*Context) DrawStringWrapped ¶
func (dc *Context) DrawStringWrapped(s string, x, y, ax, ay, width, lineSpacing float64, align Align)
DrawStringWrapped word-wraps the specified string to the given max width and then draws it at the specified anchor point using the given line spacing and text alignment.
func (*Context) Fill ¶
func (dc *Context) Fill()
Fill fills the current path with the current color. Open subpaths are implicity closed. The path is cleared after this operation.
func (*Context) FillPreserve ¶
func (dc *Context) FillPreserve()
FillPreserve fills the current path with the current color. Open subpaths are implicity closed. The path is preserved after this operation.
func (*Context) FontHeight ¶
func (*Context) GetCurrentPoint ¶
GetCurrentPoint will return the current point and if there is a current point. The point will have been transformed by the context's transformation matrix.
func (*Context) Identity ¶
func (dc *Context) Identity()
Identity resets the current transformation matrix to the identity matrix. This results in no translating, scaling, rotating, or shearing.
func (*Context) InvertMask ¶
func (dc *Context) InvertMask()
InvertMask inverts the alpha values in the current clipping mask such that a fully transparent region becomes fully opaque and vice versa.
func (*Context) InvertY ¶
func (dc *Context) InvertY()
InvertY flips the Y axis so that Y grows from bottom to top and Y=0 is at the bottom of the image.
func (*Context) LineTo ¶
LineTo adds a line segment to the current path starting at the current point. If there is no current point, it is equivalent to MoveTo(x, y)
func (*Context) MeasureMultilineString ¶
func (*Context) MeasureString ¶
MeasureString returns the rendered width and height of the specified text given the current font face.
func (*Context) MoveTo ¶
MoveTo starts a new subpath within the current path starting at the specified point.
func (*Context) NewSubPath ¶
func (dc *Context) NewSubPath()
NewSubPath starts a new subpath within the current path. There is no current point after this operation.
func (*Context) Pop ¶
func (dc *Context) Pop()
Pop restores the last saved context state from the stack.
func (*Context) Push ¶
func (dc *Context) Push()
Push saves the current state of the context for later retrieval. These can be nested.
func (*Context) QuadraticTo ¶
QuadraticTo adds a quadratic bezier curve to the current path starting at the current point. If there is no current point, it first performs MoveTo(x1, y1)
func (*Context) Rotate ¶
Rotate updates the current matrix with a anticlockwise rotation. Rotation occurs about the origin. Angle is specified in radians.
func (*Context) RotateAbout ¶
RotateAbout updates the current matrix with a anticlockwise rotation. Rotation occurs about the specified point. Angle is specified in radians.
func (*Context) Scale ¶
Scale updates the current matrix with a scaling factor. Scaling occurs about the origin.
func (*Context) ScaleAbout ¶
ScaleAbout updates the current matrix with a scaling factor. Scaling occurs about the specified point.
func (*Context) SetDash ¶
SetDash sets the current dash pattern to use. Call with zero arguments to disable dashes. The values specify the lengths of each dash, with alternating on and off lengths.
func (*Context) SetDashOffset ¶
SetDashOffset sets the initial offset into the dash pattern to use when stroking dashed paths.
func (*Context) SetFillRule ¶
func (*Context) SetFillRuleEvenOdd ¶
func (dc *Context) SetFillRuleEvenOdd()
func (*Context) SetFillRuleWinding ¶
func (dc *Context) SetFillRuleWinding()
func (*Context) SetFontFace ¶
func (*Context) SetLineCap ¶
func (*Context) SetLineCapButt ¶
func (dc *Context) SetLineCapButt()
func (*Context) SetLineCapRound ¶
func (dc *Context) SetLineCapRound()
func (*Context) SetLineCapSquare ¶
func (dc *Context) SetLineCapSquare()
func (*Context) SetLineJoin ¶
func (*Context) SetLineJoinBevel ¶
func (dc *Context) SetLineJoinBevel()
func (*Context) SetLineJoinRound ¶
func (dc *Context) SetLineJoinRound()
func (*Context) SetLineWidth ¶
func (*Context) SetMask ¶
SetMask allows you to directly set the *image.Alpha to be used as a clipping mask. It must be the same size as the context, else an error is returned and the mask is unchanged.
func (*Context) SetRGB ¶
SetRGB sets the current color. r, g, b values should be between 0 and 1, inclusive. Alpha will be set to 1 (fully opaque).
func (*Context) SetRGB255 ¶
SetRGB255 sets the current color. r, g, b values should be between 0 and 255, inclusive. Alpha will be set to 255 (fully opaque).
func (*Context) SetRGBA ¶
SetRGBA sets the current color. r, g, b, a values should be between 0 and 1, inclusive.
func (*Context) SetRGBA255 ¶
SetRGBA255 sets the current color. r, g, b, a values should be between 0 and 255, inclusive.
func (*Context) SetStrokeStyle ¶
SetStrokeStyle sets current stroke style
func (*Context) Shear ¶
Shear updates the current matrix with a shearing angle. Shearing occurs about the origin.
func (*Context) ShearAbout ¶
ShearAbout updates the current matrix with a shearing angle. Shearing occurs about the specified point.
func (*Context) Stroke ¶
func (dc *Context) Stroke()
Stroke strokes the current path with the current color, line width, line cap, line join and dash settings. The path is cleared after this operation.
func (*Context) StrokePreserve ¶
func (dc *Context) StrokePreserve()
StrokePreserve strokes the current path with the current color, line width, line cap, line join and dash settings. The path is preserved after this operation.
func (*Context) TransformPoint ¶
TransformPoint multiplies the specified point by the current matrix, returning a transformed position.
type Image ¶
type Image struct { Error error // contains filtered or unexported fields }
func Load ¶
func Load(source interface{}) *Image
Load an image from source. source can be a file path, a URL, a base64 encoded string, an *os.File, an image.Image or a byte slice.
func LoadFromBase64 ¶
LoadFromBase64 loads an image from a base64 encoded string.
func LoadFromFile ¶
LoadFromFile loads an image from a file.
func LoadFromImage ¶
LoadFromImage loads an image from an instance of image.Image.
func LoadFromImgo ¶
LoadFromImgo loads an image from an instance of Image.
func LoadFromPath ¶
LoadFromPath loads an image from a path.
func LoadFromUrl ¶
LoadFromUrl loads an image when the source is an url.
func (*Image) Blur ¶
Blur returns a blurred image. ksize is filter kernel size, it must be a odd number.
func (*Image) BorderRadius ¶
BorderRadius draws rounded corners on the image with given radius.
func (*Image) Circle ¶
Circle draws a circle at given center coordinate (x, y) with given radius and color.
func (*Image) Crop ¶
Crop Cut out a rectangular part of the current image with given width and height.
func (*Image) Ellipse ¶
Ellipse draws an ellipse at given center coordinate (x, y) with given width and height and color.
func (Image) Filesize ¶
Filesize returns the filesize of the image, if instance is initiated from an actual file.
func (*Image) GaussianBlur ¶
GaussianBlur returns a blurred image. ksize is Gaussian kernel size sigma is Gaussian kernel standard deviation.
func (Image) HttpHandler ¶
func (i Image) HttpHandler(w http.ResponseWriter, r *http.Request)
HttpHandler responds the image as an HTTP handler.
func (*Image) Insert ¶
Insert inserts source into the image at given (x, y) coordinate. source can be a file path, a URL, a base64 encoded string, an *os.File, an image.Image, a byte slice or an *Image.
func (*Image) Line ¶
Line draws a line from (x1, y1) to (x2, y2) with given color. TODO: width is not working yet.
func (*Image) Mosaic ¶
Mosaic apply mosaic filter to the image in given rectangle that (x1, y1) and (x2, y2) are the top-left and bottom-right coordinates of the rectangle. size is the size of the pixel.
func (*Image) Pixelate ¶
Pixelate apply pixelation filter to the image. size is the size of the pixel.
func (*Image) Rectangle ¶
Rectangle draws a rectangle at given coordinate (x, y) with given width and height and color.
func (*Image) Save ¶
Save saves the image to the specified path. Only png, jpeg, jpg, tiff and bmp extensions are supported. path is the path the image will be saved to. quality is the quality of the image, between 1 and 100, default is 100, and is only used for jpeg images.
func (*Image) Text ¶
func (i *Image) Text(label string, x, y int, fontPath string, fontColor color.Color, fontSize float64, dpi float64) *Image
Text write a text string to the image at given (x, y) coordinate.
func (*Image) TextWordWrap ¶
func (i *Image) TextWordWrap(label string, x, y float64, fontPath string, fontColor color.Color, fontSize float64, align string) *Image
TextWordWrap write a text string to the image at given (x, y) coordinate.
type ImageManager ¶
type ImageManager struct { }
type Matrix ¶
type Matrix struct {
XX, YX, XY, YY, X0, Y0 float64
}
func (Matrix) TransformPoint ¶
func (Matrix) TransformVector ¶
type Pattern ¶
func NewSolidPattern ¶
type Radius ¶
type Radius struct {
// contains filtered or unexported fields
}