feat: support bar margin

bar_chart.go

@@ -23,6 +23,7 @@
 package charts
 
 import (
+	"fmt"
 	"math"
 
 	"github.com/golang/freetype/truetype"
@@ -63,6 +64,8 @@ type BarChartOption struct {
 	// The legend option
 	Legend   LegendOption
 	BarWidth int
+	// Margin of bar
+	BarMargin int
 }
 
 func (b *barChart) render(result *defaultRenderResult, seriesList SeriesList) (Box, error) {
@@ -88,6 +91,10 @@ func (b *barChart) render(result *defaultRenderResult, seriesList SeriesList) (B
 		margin = 5
 		barMargin = 3
 	}
+	if opt.BarMargin > 0 {
+		barMargin = opt.BarMargin
+	}
+	fmt.Println(barMargin)
 	seriesCount := len(seriesList)
 	// 总的宽度-两个margin-(总数-1)的barMargin
 	barWidth := (width - 2*margin - barMargin*(seriesCount-1)) / seriesCount

chart_option.go

@@ -67,6 +67,8 @@ type ChartOption struct {
 	LineStrokeWidth float64
 	// The bar with of bar chart
 	BarWidth int
+	// The margin of each bar
+	BarMargin int
 	// The bar height of horizontal bar chart
 	BarHeight int
 	// Fill the area of line chart

charts.go

@@ -375,10 +375,11 @@ func Render(opt ChartOption, opts ...OptionFunc) (*Painter, error) {
 	if len(barSeriesList) != 0 {
 		handler.Add(func() error {
 			_, err := NewBarChart(p, BarChartOption{
-				Theme:    opt.theme,
-				Font:     opt.font,
-				XAxis:    opt.XAxis,
-				BarWidth: opt.BarWidth,
+				Theme:     opt.theme,
+				Font:      opt.font,
+				XAxis:     opt.XAxis,
+				BarWidth:  opt.BarWidth,
+				BarMargin: opt.BarMargin,
 			}).render(renderResult, barSeriesList)
 			return err
 		})
@@ -391,6 +392,7 @@ func Render(opt ChartOption, opts ...OptionFunc) (*Painter, error) {
 				Theme:        opt.theme,
 				Font:         opt.font,
 				BarHeight:    opt.BarHeight,
+				BarMargin:    opt.BarMargin,
 				YAxisOptions: opt.YAxisOptions,
 			}).render(renderResult, horizontalBarSeriesList)
 			return err

horizontal_bar_chart.go

@@ -50,6 +50,8 @@ type HorizontalBarChartOption struct {
 	// The legend option
 	Legend    LegendOption
 	BarHeight int
+	// Margin of bar
+	BarMargin int
 }
 
 // NewHorizontalBarChart returns a horizontal bar chart renderer
@@ -81,6 +83,9 @@ func (h *horizontalBarChart) render(result *defaultRenderResult, seriesList Seri
 		margin = 5
 		barMargin = 3
 	}
+	if opt.BarMargin > 0 {
+		barMargin = opt.BarMargin
+	}
 	seriesCount := len(seriesList)
 	// 总的高度-两个margin-(总数-1)的barMargin
 	barHeight := (height - 2*margin - barMargin*(seriesCount-1)) / seriesCount