drawing

type Color struct {
	R uint8
	G uint8
	B uint8
	A uint8
}

type ContextStack struct {
	Tr          Matrix
	Path        *Path
	LineWidth   float64
	Dash        []float64
	DashOffset  float64
	StrokeColor color.Color
	FillColor   color.Color
	FillRule    FillRule
	Cap         LineCap
	Join        LineJoin

	FontSizePoints float64
	Font           *truetype.Font

	Scale float64

	Previous *ContextStack
}

type DashVertexConverter struct {
	// contains filtered or unexported fields
}

type DemuxFlattener struct {
	Flatteners []Flattener
}

type FillRule int

type Flattener interface {
	// MoveTo Start a New line from the point (x, y)
	MoveTo(x, y float64)
	// LineTo Draw a line from the current position to the point (x, y)
	LineTo(x, y float64)
	// LineJoin add the most recent starting point to close the path to create a polygon
	LineJoin()
	// Close add the most recent starting point to close the path to create a polygon
	Close()
	// End mark the current line as finished so we can draw caps
	End()
}

type FontExtents struct {
	// Ascent is the distance that the text
	// extends above the baseline.
	Ascent float64

	// Descent is the distance that the text
	// extends below the baseline.  The descent
	// is given as a negative value.
	Descent float64

	// Height is the distance from the lowest
	// descending point to the highest ascending
	// point.
	Height float64
}

type FtLineBuilder struct {
	Adder raster.Adder
}

type GraphicContext interface {
	// PathBuilder describes the interface for path drawing
	PathBuilder
	// BeginPath creates a new path
	BeginPath()
	// GetMatrixTransform returns the current transformation matrix
	GetMatrixTransform() Matrix
	// SetMatrixTransform sets the current transformation matrix
	SetMatrixTransform(tr Matrix)
	// ComposeMatrixTransform composes the current transformation matrix with tr
	ComposeMatrixTransform(tr Matrix)
	// Rotate applies a rotation to the current transformation matrix. angle is in radian.
	Rotate(angle float64)
	// Translate applies a translation to the current transformation matrix.
	Translate(tx, ty float64)
	// Scale applies a scale to the current transformation matrix.
	Scale(sx, sy float64)
	// SetStrokeColor sets the current stroke color
	SetStrokeColor(c color.Color)
	// SetFillColor sets the current fill color
	SetFillColor(c color.Color)
	// SetFillRule sets the current fill rule
	SetFillRule(f FillRule)
	// SetLineWidth sets the current line width
	SetLineWidth(lineWidth float64)
	// SetLineCap sets the current line cap
	SetLineCap(cap LineCap)
	// SetLineJoin sets the current line join
	SetLineJoin(join LineJoin)
	// SetLineDash sets the current dash
	SetLineDash(dash []float64, dashOffset float64)
	// SetFontSize sets the current font size
	SetFontSize(fontSize float64)
	// GetFontSize gets the current font size
	GetFontSize() float64
	// SetFont sets the font for the context
	SetFont(f *truetype.Font)
	// GetFont returns the current font
	GetFont() *truetype.Font
	// DrawImage draws the raster image in the current canvas
	DrawImage(image image.Image)
	// Save the context and push it to the context stack
	Save()
	// Restore remove the current context and restore the last one
	Restore()
	// Clear fills the current canvas with a default transparent color
	Clear()
	// ClearRect fills the specified rectangle with a default transparent color
	ClearRect(x1, y1, x2, y2 int)
	// SetDPI sets the current DPI
	SetDPI(dpi int)
	// GetDPI gets the current DPI
	GetDPI() int
	// GetStringBounds gets pixel bounds(dimensions) of given string
	GetStringBounds(s string) (left, top, right, bottom float64)
	// CreateStringPath creates a path from the string s at x, y
	CreateStringPath(text string, x, y float64) (cursor float64)
	// FillString draws the text at point (0, 0)
	FillString(text string) (cursor float64)
	// FillStringAt draws the text at the specified point (x, y)
	FillStringAt(text string, x, y float64) (cursor float64)
	// StrokeString draws the contour of the text at point (0, 0)
	StrokeString(text string) (cursor float64)
	// StrokeStringAt draws the contour of the text at point (x, y)
	StrokeStringAt(text string, x, y float64) (cursor float64)
	// Stroke strokes the paths with the color specified by SetStrokeColor
	Stroke(paths ...*Path)
	// Fill fills the paths with the color specified by SetFillColor
	Fill(paths ...*Path)
	// FillStroke first fills the paths and than strokes them
	FillStroke(paths ...*Path)
}

type Halign int

type ImageFilter int

type ImageScaling struct {
	// Horizontal Alignment of the image
	Halign Halign
	// Vertical Alignment of the image
	Valign Valign
	// Width Height used by scaling policy
	Width, Height float64
	// ScalingPolicy defines the scaling policy to applied to the image
	ScalingPolicy ScalingPolicy
}

type LineCap int

type LineJoin int

type LineStroker struct {
	Flattener     Flattener
	HalfLineWidth float64
	Cap           LineCap
	Join          LineJoin
	// contains filtered or unexported fields
}

type Liner interface {
	// LineTo Draw a line from the current position to the point (x, y)
	LineTo(x, y float64)
}

type Matrix [6]float64

type Painter interface {
	raster.Painter
	SetColor(color color.Color)
}

type Path struct {
	// Components is a slice of PathComponent in a Path and mark the role of each points in the Path
	Components []PathComponent
	// Points are combined with Components to have a specific role in the path
	Points []float64
	// contains filtered or unexported fields
}

type PathBuilder interface {
	// LastPoint returns the current point of the current sub path
	LastPoint() (x, y float64)
	// MoveTo creates a new subpath that start at the specified point
	MoveTo(x, y float64)
	// LineTo adds a line to the current subpath
	LineTo(x, y float64)
	// QuadCurveTo adds a quadratic Bézier curve to the current subpath
	QuadCurveTo(cx, cy, x, y float64)
	// CubicCurveTo adds a cubic Bézier curve to the current subpath
	CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64)
	// ArcTo adds an arc to the current subpath
	ArcTo(cx, cy, rx, ry, startAngle, angle float64)
	// Close creates a line from the current point to the last MoveTo
	// point (if not the same) and mark the path as closed so the
	// first and last lines join nicely.
	Close()
}

type PathComponent int

type RasterGraphicContext struct {
	*StackGraphicContext

	DPI float64
	// contains filtered or unexported fields
}

type ScalingPolicy int

type SegmentedPath struct {
	Points []float64
}

type SolidFillStyle struct {
	// Color defines the line color
	Color color.Color
	// FillRule defines the file rule to used
	FillRule FillRule
}

type StackGraphicContext struct {
	// contains filtered or unexported fields
}

type StrokeStyle struct {
	// Color defines the color of stroke
	Color color.Color
	// Line width
	Width float64
	// Line cap style rounded, butt or square
	LineCap LineCap
	// Line join style bevel, round or miter
	LineJoin LineJoin
	// offset of the first dash
	DashOffset float64
	// array represented dash length pair values are plain dash and impair are space between dash
	// if empty display plain line
	Dash []float64
}

type TextStyle struct {
	// Color defines the color of text
	Color color.Color
	// Size font size
	Size float64
	// The font to use
	Font *truetype.Font
	// Horizontal Alignment of the text
	Halign Halign
	// Vertical Alignment of the text
	Valign Valign
}

type Transformer struct {
	Tr        Matrix
	Flattener Flattener
}

type Valign int