feat: support series label for horizontal bar

bar_chart.go

@@ -186,6 +186,7 @@ func (b *barChart) render(result *defaultRenderResult, seriesList SeriesList) (B
 				// 旋转
 				Radians:   radians,
 				FontColor: fontColor,
+				Offset:    series.Label.Offset,
 			})
 		}
 

horizontal_bar_chart.go

@@ -99,11 +99,25 @@ func (h *horizontalBarChart) render(result *defaultRenderResult, seriesList Seri
 		DivideCount: defaultAxisDivideCount,
 		Size:        seriesPainter.Width(),
 	})
+	seriesNames := seriesList.Names()
 
+	rendererList := []Renderer{}
 	for index := range seriesList {
 		series := seriesList[index]
 		seriesColor := theme.GetSeriesColor(series.index)
 		divideValues := yRange.AutoDivide()
+
+		var labelPainter *SeriesLabelPainter
+		if series.Label.Show {
+			labelPainter = NewSeriesLabelPainter(SeriesLabelPainterParams{
+				P:           seriesPainter,
+				SeriesNames: seriesNames,
+				Label:       series.Label,
+				Theme:       opt.Theme,
+				Font:        opt.Font,
+			})
+			rendererList = append(rendererList, labelPainter)
+		}
 		for j, item := range series.Data {
 			if j >= yRange.divideCount {
 				continue
@@ -130,7 +144,34 @@ func (h *horizontalBarChart) render(result *defaultRenderResult, seriesList Seri
 				Right:  right,
 				Bottom: y + barHeight,
 			})
+			// 如果label不需要展示，则返回
+			if labelPainter == nil {
+				continue
 			}
+			x := right
+			var fontColor Color
+			if series.Label.Position == PositionLeft {
+				x = 0
+				if isLightColor(fillColor) {
+					fontColor = defaultLightFontColor
+				} else {
+					fontColor = defaultDarkFontColor
+				}
+			}
+			labelPainter.Add(LabelValue{
+				Orient:    OrientHorizontal,
+				Index:     index,
+				Value:     item.Value,
+				X:         x,
+				Y:         y + barHeight>>1,
+				FontColor: fontColor,
+				Offset:    series.Label.Offset,
+			})
+		}
+	}
+	err := doRender(rendererList...)
+	if err != nil {
+		return BoxZero, err
 	}
 	return p.box, nil
 }

series.go

@@ -81,6 +81,8 @@ type SeriesLabel struct {
 	Distance int
 	// The position of label
 	Position string
+	// The offset of label's position
+	Offset Box
 }
 
 const (

series_label.go

@@ -45,6 +45,8 @@ type LabelValue struct {
 	Radians float64
 	// 字体颜色
 	FontColor Color
+	Orient    string
+	Offset    Box
 }
 
 type SeriesLabelPainter struct {
@@ -103,10 +105,18 @@ func (o *SeriesLabelPainter) Add(value LabelValue) {
 	renderValue := labelRenderValue{
 		Text:    text,
 		Style:   labelStyle,
-		X:       value.X - textBox.Width()>>1,
-		Y:       value.Y - distance,
+		X:       value.X,
+		Y:       value.Y,
 		Radians: value.Radians,
 	}
+	if value.Orient != OrientHorizontal {
+		renderValue.X -= textBox.Width() >> 1
+		renderValue.Y -= distance
+	} else {
+		renderValue.X += distance
+		renderValue.Y += textBox.Height() >> 1
+		renderValue.Y -= 2
+	}
 	if rotated {
 		renderValue.X = value.X + textBox.Width()>>1 - 1
 		p.ClearTextRotation()
@@ -115,6 +125,8 @@ func (o *SeriesLabelPainter) Add(value LabelValue) {
 			renderValue.X++
 		}
 	}
+	renderValue.X += value.Offset.Left
+	renderValue.Y += value.Offset.Top
 	o.values = append(o.values, renderValue)
 }