feat: support pie, radar and funnel chart

radar_chart.go

@@ -0,0 +1,245 @@
+// 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 (
+	"errors"
+
+	"github.com/golang/freetype/truetype"
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
+
+type radarChart struct {
+	p   *Painter
+	opt *RadarChartOption
+}
+
+type RadarIndicator struct {
+	// Indicator's name
+	Name string
+	// The maximum value of indicator
+	Max float64
+	// The minimum value of indicator
+	Min float64
+}
+
+type RadarChartOption struct {
+	Theme ColorPalette
+	// The font size
+	Font *truetype.Font
+	// The data series list
+	SeriesList SeriesList
+	// The padding of line chart
+	Padding Box
+	// The option of title
+	Title TitleOption
+	// The legend option
+	Legend LegendOption
+	// The radar indicator list
+	RadarIndicators []RadarIndicator
+	// background is filled
+	backgroundIsFilled bool
+}
+
+func NewRadarChart(p *Painter, opt RadarChartOption) *radarChart {
+	if opt.Theme == nil {
+		opt.Theme = NewTheme("")
+	}
+	return &radarChart{
+		p:   p,
+		opt: &opt,
+	}
+}
+
+func (r *radarChart) render(result *defaultRenderResult, seriesList SeriesList) (Box, error) {
+	opt := r.opt
+	indicators := opt.RadarIndicators
+	sides := len(indicators)
+	if sides < 3 {
+		return BoxZero, errors.New("The count of indicator should be >= 3")
+	}
+	maxValues := make([]float64, len(indicators))
+	for _, series := range seriesList {
+		for index, item := range series.Data {
+			if index < len(maxValues) && item.Value > maxValues[index] {
+				maxValues[index] = item.Value
+			}
+		}
+	}
+	for index, indicator := range indicators {
+		if indicator.Max <= 0 {
+			indicators[index].Max = maxValues[index]
+		}
+	}
+
+	radiusValue := ""
+	for _, series := range seriesList {
+		if len(series.Radius) != 0 {
+			radiusValue = series.Radius
+		}
+	}
+
+	seriesPainter := result.seriesPainter
+	theme := opt.Theme
+
+	cx := seriesPainter.Width() >> 1
+	cy := seriesPainter.Height() >> 1
+	diameter := chart.MinInt(seriesPainter.Width(), seriesPainter.Height())
+	radius := getRadius(float64(diameter), radiusValue)
+
+	divideCount := 5
+	divideRadius := float64(int(radius / float64(divideCount)))
+	radius = divideRadius * float64(divideCount)
+
+	seriesPainter.OverrideDrawingStyle(Style{
+		StrokeColor: theme.GetAxisSplitLineColor(),
+		StrokeWidth: 1,
+	})
+	center := Point{
+		X: cx,
+		Y: cy,
+	}
+	for i := 0; i < divideCount; i++ {
+		seriesPainter.Polygon(center, divideRadius*float64(i+1), sides)
+	}
+	points := getPolygonPoints(center, radius, sides)
+	for _, p := range points {
+		seriesPainter.MoveTo(center.X, center.Y)
+		seriesPainter.LineTo(p.X, p.Y)
+		seriesPainter.Stroke()
+	}
+	seriesPainter.OverrideTextStyle(Style{
+		FontColor: theme.GetTextColor(),
+		FontSize:  labelFontSize,
+		Font:      opt.Font,
+	})
+	offset := 5
+	// 文本生成
+	for index, p := range points {
+		name := indicators[index].Name
+		b := seriesPainter.MeasureText(name)
+		isXCenter := p.X == center.X
+		isYCenter := p.Y == center.Y
+		isRight := p.X > center.X
+		isLeft := p.X < center.X
+		isTop := p.Y < center.Y
+		isBottom := p.Y > center.Y
+		x := p.X
+		y := p.Y
+		if isXCenter {
+			x -= b.Width() >> 1
+			if isTop {
+				y -= b.Height()
+			} else {
+				y += b.Height()
+			}
+		}
+		if isYCenter {
+			y += b.Height() >> 1
+		}
+		if isTop {
+			y += offset
+		}
+		if isBottom {
+			y += offset
+		}
+		if isRight {
+			x += offset
+		}
+		if isLeft {
+			x -= (b.Width() + offset)
+		}
+		seriesPainter.Text(name, x, y)
+	}
+
+	// 雷达图
+	angles := getPolygonPointAngles(sides)
+	maxCount := len(indicators)
+	for _, series := range seriesList {
+		linePoints := make([]Point, 0, maxCount)
+		for j, item := range series.Data {
+			if j >= maxCount {
+				continue
+			}
+			indicator := indicators[j]
+			percent := (item.Value - indicator.Min) / (indicator.Max - indicator.Min)
+			r := percent * radius
+			p := getPolygonPoint(center, r, angles[j])
+			linePoints = append(linePoints, p)
+		}
+		color := theme.GetSeriesColor(series.index)
+		dotFillColor := drawing.ColorWhite
+		if theme.IsDark() {
+			dotFillColor = color
+		}
+		linePoints = append(linePoints, linePoints[0])
+		seriesPainter.OverrideDrawingStyle(Style{
+			StrokeColor: color,
+			StrokeWidth: defaultStrokeWidth,
+			DotWidth:    defaultDotWidth,
+			DotColor:    color,
+			FillColor:   color.WithAlpha(20),
+		})
+		seriesPainter.LineStroke(linePoints).
+			FillArea(linePoints)
+		dotWith := 2.0
+		seriesPainter.OverrideDrawingStyle(Style{
+			StrokeWidth: defaultStrokeWidth,
+			StrokeColor: color,
+			FillColor:   dotFillColor,
+		})
+		for _, point := range linePoints {
+			seriesPainter.Circle(dotWith, point.X, point.Y)
+			seriesPainter.FillStroke()
+		}
+	}
+
+	return r.p.box, nil
+}
+
+func (r *radarChart) Render() (Box, error) {
+	p := r.p
+	opt := r.opt
+	renderResult, err := defaultRender(p, defaultRenderOption{
+		Theme:      opt.Theme,
+		Padding:    opt.Padding,
+		SeriesList: opt.SeriesList,
+		XAxis: XAxisOption{
+			Show: FalseFlag(),
+		},
+		YAxisOptions: []YAxisOption{
+			{
+				Show: FalseFlag(),
+			},
+		},
+		TitleOption:        opt.Title,
+		LegendOption:       opt.Legend,
+		backgroundIsFilled: opt.backgroundIsFilled,
+	})
+	if err != nil {
+		return BoxZero, err
+	}
+	seriesList := opt.SeriesList.Filter(ChartTypeRadar)
+	return r.render(renderResult, seriesList)
+}