feat: support painter for chart draw function

alias.go

@@ -0,0 +1,33 @@
+// MIT License
+
+// Copyright (c) 2022 Tree Xie
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package charts
+
+import (
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
+
+type Box = chart.Box
+type Renderer = chart.Renderer
+type Style = chart.Style
+type Color = drawing.Color

line.go

@@ -24,18 +24,17 @@ package charts
 
 import (
 	"github.com/wcharczuk/go-chart/v2"
-	"github.com/wcharczuk/go-chart/v2/drawing"
 )
 
 type LineStyle struct {
 	ClassName       string
 	StrokeDashArray []float64
-	StrokeColor     drawing.Color
+	StrokeColor     Color
 	StrokeWidth     float64
-	FillColor       drawing.Color
+	FillColor       Color
 	DotWidth        float64
-	DotColor        drawing.Color
+	DotColor        Color
-	DotFillColor    drawing.Color
+	DotFillColor    Color
 }
 
 func (ls *LineStyle) Style() chart.Style {

painer.go

@@ -0,0 +1,394 @@
+// MIT License
+
+// Copyright (c) 2022 Tree Xie
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package charts
+
+import (
+	"bytes"
+	"errors"
+	"math"
+
+	"github.com/golang/freetype/truetype"
+	"github.com/wcharczuk/go-chart/v2"
+)
+
+type Painter struct {
+	render        Renderer
+	box           Box
+	font          *truetype.Font
+	parent        *Painter
+	style         Style
+	previousStyle Style
+}
+
+type PainterOptions struct {
+	// Draw type, "svg" or "png", default type is "svg"
+	Type string
+	// The width of draw canvas
+	Width int
+	// The height of draw canvas
+	Height int
+	// The font for painter
+	Font *truetype.Font
+}
+
+type PainterOption func(*Painter)
+
+// PainterPaddingOption sets the padding of draw canvas
+func PainterPaddingOption(padding Box) PainterOption {
+	return func(p *Painter) {
+		p.box.Left += padding.Left
+		p.box.Top += padding.Top
+		p.box.Right -= padding.Right
+		p.box.Bottom -= padding.Bottom
+	}
+}
+
+// PainterBoxOption sets the box of draw canvas
+func PainterBoxOption(box Box) PainterOption {
+	return func(p *Painter) {
+		if box.IsZero() {
+			return
+		}
+		p.box = box
+	}
+}
+
+// PainterFontOption sets the font of draw canvas
+func PainterFontOption(font *truetype.Font) PainterOption {
+	return func(p *Painter) {
+		p.font = font
+	}
+}
+
+// PainterStyleOption sets the style of draw canvas
+func PainterStyleOption(style Style) PainterOption {
+	return func(p *Painter) {
+		p.SetDrawingStyle(style)
+	}
+}
+
+// NewPainter creates a new Painter
+func NewPainter(opts PainterOptions, opt ...PainterOption) (*Painter, error) {
+	if opts.Width <= 0 || opts.Height <= 0 {
+		return nil, errors.New("width/height can not be nil")
+	}
+	font := opts.Font
+	if font == nil {
+		f, err := chart.GetDefaultFont()
+		if err != nil {
+			return nil, err
+		}
+		font = f
+	}
+	fn := chart.SVG
+	if opts.Type == ChartOutputPNG {
+		fn = chart.PNG
+	}
+	width := opts.Width
+	height := opts.Height
+	r, err := fn(width, height)
+	if err != nil {
+		return nil, err
+	}
+	p := &Painter{
+		render: r,
+		box: Box{
+			Right:  opts.Width,
+			Bottom: opts.Height,
+		},
+		font: font,
+	}
+	p.setOptions(opt...)
+	return p, nil
+}
+func (p *Painter) setOptions(opts ...PainterOption) {
+	for _, fn := range opts {
+		fn(p)
+	}
+}
+
+func (p *Painter) Child(opt ...PainterOption) *Painter {
+	child := &Painter{
+		render:        p.render,
+		box:           p.box.Clone(),
+		font:          p.font,
+		parent:        p,
+		style:         p.style,
+		previousStyle: p.previousStyle,
+	}
+	child.setOptions(opt...)
+	return child
+}
+
+func (p *Painter) SetStyle(style Style) {
+	p.previousStyle = p.style
+	p.style = style
+	style.WriteToRenderer(p.render)
+}
+
+func (p *Painter) SetDrawingStyle(style Style) {
+	p.previousStyle = p.style
+	p.style = style
+	style.WriteDrawingOptionsToRenderer(p.render)
+}
+
+func (p *Painter) SetTextStyle(style Style) {
+	p.previousStyle = p.style
+	p.style = style
+	style.WriteTextOptionsToRenderer(p.render)
+}
+
+func (p *Painter) RestoreStyle() {
+	p.style = p.previousStyle
+}
+
+// Bytes returns the data of draw canvas
+func (p *Painter) Bytes() ([]byte, error) {
+	buffer := bytes.Buffer{}
+	err := p.render.Save(&buffer)
+	if err != nil {
+		return nil, err
+	}
+	return buffer.Bytes(), err
+}
+
+// MoveTo moves the cursor to a given point
+func (p *Painter) MoveTo(x, y int) {
+	p.render.MoveTo(x+p.box.Left, y+p.box.Top)
+}
+
+func (p *Painter) ArcTo(cx, cy int, rx, ry, startAngle, delta float64) {
+	p.render.ArcTo(cx+p.box.Left, cy+p.box.Top, rx, ry, startAngle, delta)
+}
+
+func (p *Painter) LineTo(x, y int) {
+	p.render.LineTo(x+p.box.Left, y+p.box.Top)
+}
+
+func (p *Painter) Pin(x, y, width int) {
+	r := float64(width) / 2
+	y -= width / 4
+	angle := chart.DegreesToRadians(15)
+	box := p.box
+
+	startAngle := math.Pi/2 + angle
+	delta := 2*math.Pi - 2*angle
+	p.ArcTo(x, y, r, r, startAngle, delta)
+	p.LineTo(x, y)
+	p.Close()
+	p.FillStroke()
+
+	startX := x - int(r)
+	startY := y
+	endX := x + int(r)
+	endY := y
+	p.MoveTo(startX, startY)
+
+	left := box.Left
+	top := box.Top
+	cx := x
+	cy := y + int(r*2.5)
+	p.render.QuadCurveTo(cx+left, cy+top, endX+left, endY+top)
+	p.Close()
+	p.Fill()
+}
+
+func (p *Painter) arrow(x, y, width, height int, direction string) {
+	halfWidth := width >> 1
+	halfHeight := height >> 1
+	if direction == PositionTop || direction == PositionBottom {
+		x0 := x - halfWidth
+		x1 := x0 + width
+		dy := -height / 3
+		y0 := y
+		y1 := y0 - height
+		if direction == PositionBottom {
+			y0 = y - height
+			y1 = y
+			dy = 2 * dy
+		}
+		p.MoveTo(x0, y0)
+		p.LineTo(x0+halfWidth, y1)
+		p.LineTo(x1, y0)
+		p.LineTo(x0+halfWidth, y+dy)
+		p.LineTo(x0, y0)
+	} else {
+		x0 := x + width
+		x1 := x0 - width
+		y0 := y - halfHeight
+		dx := -width / 3
+		if direction == PositionRight {
+			x0 = x - width
+			dx = -dx
+			x1 = x0 + width
+		}
+		p.MoveTo(x0, y0)
+		p.LineTo(x1, y0+halfHeight)
+		p.LineTo(x0, y0+height)
+		p.LineTo(x0+dx, y0+halfHeight)
+		p.LineTo(x0, y0)
+	}
+	p.FillStroke()
+}
+
+func (p *Painter) ArrowLeft(x, y, width, height int) {
+	p.arrow(x, y, width, height, PositionLeft)
+}
+
+func (p *Painter) ArrowRight(x, y, width, height int) {
+	p.arrow(x, y, width, height, PositionRight)
+}
+
+func (p *Painter) ArrowTop(x, y, width, height int) {
+	p.arrow(x, y, width, height, PositionTop)
+}
+func (p *Painter) ArrowBottom(x, y, width, height int) {
+	p.arrow(x, y, width, height, PositionBottom)
+}
+
+func (p *Painter) Circle(radius float64, x, y int) {
+	p.render.Circle(radius, x+p.box.Left, y+p.box.Top)
+}
+
+func (p *Painter) Stroke() {
+	p.render.Stroke()
+}
+
+func (p *Painter) Close() {
+	p.render.Close()
+}
+
+func (p *Painter) FillStroke() {
+	p.render.FillStroke()
+}
+
+func (p *Painter) Fill() {
+	p.render.Fill()
+}
+
+func (p *Painter) LineStroke(points []Point, style LineStyle) {
+	s := style.Style()
+	if !s.ShouldDrawStroke() {
+		return
+	}
+	defer p.RestoreStyle()
+	p.SetDrawingStyle(s.GetStrokeOptions())
+	for index, point := range points {
+		x := point.X
+		y := point.Y
+		if index == 0 {
+			p.MoveTo(x, y)
+		} else {
+			p.LineTo(x, y)
+		}
+	}
+	p.Stroke()
+}
+
+func (p *Painter) SetBackground(width, height int, color Color) {
+	r := p.render
+	s := chart.Style{
+		FillColor: color,
+	}
+	defer p.RestoreStyle()
+	p.SetStyle(s)
+	// 设置背景色不使用box，因此不直接使用Painter
+	r.MoveTo(0, 0)
+	r.LineTo(width, 0)
+	r.LineTo(width, height)
+	r.LineTo(0, height)
+	r.LineTo(0, 0)
+	p.FillStroke()
+}
+func (p *Painter) MarkLine(x, y, width int) {
+	arrowWidth := 16
+	arrowHeight := 10
+	endX := x + width
+	p.Circle(3, x, y)
+	p.render.Fill()
+	p.MoveTo(x+5, y)
+	p.LineTo(endX-arrowWidth, y)
+	p.Stroke()
+	p.render.SetStrokeDashArray([]float64{})
+	p.ArrowRight(endX, y, arrowWidth, arrowHeight)
+}
+
+func (p *Painter) Polygon(center Point, radius float64, sides int) {
+	points := getPolygonPoints(center, radius, sides)
+	for i, item := range points {
+		if i == 0 {
+			p.MoveTo(item.X, item.Y)
+		} else {
+			p.LineTo(item.X, item.Y)
+		}
+	}
+	p.LineTo(points[0].X, points[0].Y)
+	p.Stroke()
+}
+
+func (p *Painter) FillArea(points []Point, s Style) {
+	if !s.ShouldDrawFill() {
+		return
+	}
+	defer p.RestoreStyle()
+	var x, y int
+	p.SetDrawingStyle(s.GetFillOptions())
+	for index, point := range points {
+		x = point.X
+		y = point.Y
+		if index == 0 {
+			p.MoveTo(x, y)
+		} else {
+			p.LineTo(x, y)
+		}
+	}
+	p.Fill()
+}
+
+func (p *Painter) Text(body string, x, y int) {
+	p.render.Text(body, x+p.box.Left, y+p.box.Top)
+}
+
+func (p *Painter) TextFit(body string, x, y, width int) chart.Box {
+	style := p.style
+	textWarp := style.TextWrap
+	style.TextWrap = chart.TextWrapWord
+	r := p.render
+	lines := chart.Text.WrapFit(r, body, width, style)
+	p.SetTextStyle(style)
+	var output chart.Box
+
+	for index, line := range lines {
+		x0 := x
+		y0 := y + output.Height()
+		p.Text(line, x0, y0)
+		lineBox := r.MeasureText(line)
+		output.Right = chart.MaxInt(lineBox.Right, output.Right)
+		output.Bottom += lineBox.Height()
+		if index < len(lines)-1 {
+			output.Bottom += +style.GetTextLineSpacing()
+		}
+	}
+	p.style.TextWrap = textWarp
+	return output
+}

painer_test.go

@@ -0,0 +1,371 @@
+// MIT License
+
+// Copyright (c) 2022 Tree Xie
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package charts
+
+import (
+	"math"
+	"testing"
+
+	"github.com/golang/freetype/truetype"
+	"github.com/stretchr/testify/assert"
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
+
+func TestPainterOption(t *testing.T) {
+	assert := assert.New(t)
+
+	font := &truetype.Font{}
+	d, err := NewPainter(PainterOptions{
+		Width:  800,
+		Height: 600,
+	},
+		PainterBoxOption(Box{
+			Right:  400,
+			Bottom: 300,
+		}),
+		PainterPaddingOption(Box{
+			Left:   1,
+			Top:    2,
+			Right:  3,
+			Bottom: 4,
+		}),
+		PainterFontOption(font),
+		PainterStyleOption(Style{
+			ClassName: "test",
+		}),
+	)
+	assert.Nil(err)
+	assert.Equal(Box{
+		Left:   1,
+		Top:    2,
+		Right:  397,
+		Bottom: 296,
+	}, d.box)
+	assert.Equal(font, d.font)
+	assert.Equal("test", d.style.ClassName)
+}
+
+func TestPainter(t *testing.T) {
+	assert := assert.New(t)
+
+	tests := []struct {
+		fn     func(*Painter)
+		result string
+	}{
+		// moveTo, lineTo
+		{
+			fn: func(p *Painter) {
+				p.MoveTo(1, 1)
+				p.LineTo(2, 2)
+				p.Stroke()
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 6 11\nL 7 12\" style=\"stroke-width:0;stroke:none;fill:none\"/></svg>",
+		},
+		// circle
+		{
+			fn: func(p *Painter) {
+				p.Circle(5, 2, 3)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<circle cx=\"7\" cy=\"13\" r=\"5\" style=\"stroke-width:0;stroke:none;fill:none\"/></svg>",
+		},
+		// text
+		{
+			fn: func(p *Painter) {
+				p.Text("hello world!", 3, 6)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<text x=\"8\" y=\"16\" style=\"stroke-width:0;stroke:none;fill:none\">hello world!</text></svg>",
+		},
+		// line stroke
+		{
+			fn: func(p *Painter) {
+				p.LineStroke([]Point{
+					{
+						X: 1,
+						Y: 2,
+					},
+					{
+						X: 3,
+						Y: 4,
+					},
+				}, LineStyle{
+					StrokeColor: drawing.ColorBlack,
+					StrokeWidth: 1,
+				})
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 6 12\nL 8 14\" style=\"stroke-width:1;stroke:rgba(0,0,0,1.0);fill:none\"/></svg>",
+		},
+		// set background
+		{
+			fn: func(p *Painter) {
+				p.SetBackground(400, 300, chart.ColorWhite)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 0 0\nL 400 0\nL 400 300\nL 0 300\nL 0 0\" style=\"stroke-width:0;stroke:none;fill:rgba(255,255,255,1.0)\"/></svg>",
+		},
+		// arcTo
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.ColorBlack,
+					FillColor:   drawing.ColorBlue,
+				})
+				p.ArcTo(100, 100, 100, 100, 0, math.Pi/2)
+				p.Close()
+				p.FillStroke()
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 205 110\nA 100 100 90.00 0 1 105 210\nZ\" style=\"stroke-width:1;stroke:rgba(0,0,0,1.0);fill:rgba(0,0,255,1.0)\"/></svg>",
+		},
+		// pin
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.Pin(30, 30, 30)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 32 47\nA 15 15 330.00 1 1 38 47\nL 35 33\nZ\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/><path  d=\"M 20 33\nQ35,70 50,33\nZ\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// arrow left
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.ArrowLeft(30, 30, 16, 10)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 51 35\nL 35 40\nL 51 45\nL 46 40\nL 51 35\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// arrow right
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.ArrowRight(30, 30, 16, 10)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 19 35\nL 35 40\nL 19 45\nL 24 40\nL 19 35\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// arrow top
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.ArrowTop(30, 30, 10, 16)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 30 40\nL 35 24\nL 40 40\nL 35 35\nL 30 40\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// arrow bottom
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.ArrowBottom(30, 30, 10, 16)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 30 24\nL 35 40\nL 40 24\nL 35 30\nL 30 24\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// mark line
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+					StrokeDashArray: []float64{
+						4,
+						2,
+					},
+				})
+				p.MarkLine(0, 20, 300)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<circle cx=\"5\" cy=\"30\" r=\"3\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/><path stroke-dasharray=\"4.0, 2.0\" d=\"\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/><path stroke-dasharray=\"4.0, 2.0\" d=\"M 10 30\nL 289 30\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/><path  d=\"M 289 25\nL 305 30\nL 289 35\nL 294 30\nL 289 25\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+		// polygon
+		{
+			fn: func(p *Painter) {
+				p.SetStyle(Style{
+					StrokeWidth: 1,
+					StrokeColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+				p.Polygon(Point{
+					X: 100,
+					Y: 100,
+				}, 50, 6)
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 105 60\nL 148 85\nL 148 134\nL 105 160\nL 62 135\nL 62 86\nL 105 60\" style=\"stroke-width:1;stroke:rgba(84,112,198,1.0);fill:none\"/></svg>",
+		},
+		// FillArea
+		{
+			fn: func(p *Painter) {
+				p.FillArea([]Point{
+					{
+						X: 0,
+						Y: 0,
+					},
+					{
+						X: 0,
+						Y: 100,
+					},
+					{
+						X: 100,
+						Y: 100,
+					},
+					{
+						X: 0,
+						Y: 0,
+					},
+				}, Style{
+					FillColor: drawing.Color{
+						R: 84,
+						G: 112,
+						B: 198,
+						A: 255,
+					},
+				})
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<path  d=\"M 5 10\nL 5 110\nL 105 110\nL 5 10\" style=\"stroke-width:0;stroke:none;fill:rgba(84,112,198,1.0)\"/></svg>",
+		},
+	}
+	for _, tt := range tests {
+		d, err := NewPainter(PainterOptions{
+			Width:  400,
+			Height: 300,
+		}, PainterPaddingOption(chart.Box{
+			Left: 5,
+			Top:  10,
+		}))
+		assert.Nil(err)
+		tt.fn(d)
+		data, err := d.Bytes()
+		assert.Nil(err)
+		assert.Equal(tt.result, string(data))
+	}
+}
+
+func TestPainterTextFit(t *testing.T) {
+	assert := assert.New(t)
+	p, err := NewPainter(PainterOptions{
+		Width:  400,
+		Height: 300,
+	})
+	assert.Nil(err)
+	f, _ := chart.GetDefaultFont()
+	style := Style{
+		FontSize:  12,
+		FontColor: chart.ColorBlack,
+		Font:      f,
+	}
+	p.SetStyle(style)
+	box := p.TextFit("Hello World!", 0, 20, 80)
+	assert.Equal(chart.Box{
+		Right:  45,
+		Bottom: 35,
+	}, box)
+
+	box = p.TextFit("Hello World!", 0, 100, 200)
+	assert.Equal(chart.Box{
+		Right:  84,
+		Bottom: 15,
+	}, box)
+
+	buf, err := p.Bytes()
+	assert.Nil(err)
+	assert.Equal(`<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="400" height="300">\n<text x="0" y="20" style="stroke-width:0;stroke:none;fill:rgba(51,51,51,1.0);font-size:15.3px;font-family:'Roboto Medium',sans-serif">Hello</text><text x="0" y="40" style="stroke-width:0;stroke:none;fill:rgba(51,51,51,1.0);font-size:15.3px;font-family:'Roboto Medium',sans-serif">World!</text><text x="0" y="100" style="stroke-width:0;stroke:none;fill:rgba(51,51,51,1.0);font-size:15.3px;font-family:'Roboto Medium',sans-serif">Hello World!</text></svg>`, string(buf))
+}