Feat: add polar bar

[susiwen8]

New Feature

• Polar bar

New API

• EablePolarType
• WithPolarOps
• WithAngleAxisOps
• WithRadiusAxisOps

Example

package main

import (
	"math/rand"
	"os"

	"github.com/go-echarts/go-echarts/v2/charts"
	"github.com/go-echarts/go-echarts/v2/opts"
	"github.com/go-echarts/go-echarts/v2/types"
)

// generate random data for bar chart
func generateBarItems() []opts.BarData {
	items := make([]opts.BarData, 0)
	for i := 0; i < 7; i++ {
		items = append(items, opts.BarData{Value: rand.Intn(300)})
	}
	return items
}

func main() {
	bar := charts.NewBar()
	bar.SetGlobalOptions(
		charts.WithInitializationOpts(opts.Initialization{Theme: "white"}),
		charts.WithTitleOpts(opts.Title{
			Title: "Polar Bar",
		}),
		charts.WithPolarOps(opts.Polar{
			Radius: [2]string{"0", "100"},
			Center: [2]string{"50%", "50%"},
			Tooltip: opts.Tooltip{
				Show: true,
			},
		}),
		charts.WithAngleAxisOps(opts.AngleAxis{
			PolarAxisBase: opts.PolarAxisBase{
				// Max:        2,
				// StartAngle: 30,
			},
		}),
		charts.WithRadiusAxisOps(opts.RadiusAxis{
			PolarAxisBase: opts.PolarAxisBase{
				Type: "category",
			},
		}),
	)
	bar.EnablePolarType().
		AddSeries("Category A", generateBarItems()).
		AddSeries("Category B", generateBarItems()).
		SetSeriesOptions(charts.WithBarChartOpts(opts.BarChart{
			Stack:          "stackA",
			ShowBackground: true,
			CoordSystem:    "polar",
			RoundCap:       true,
			Type:           types.ChartBar,
		}))
	// Where the magic happens
	f, _ := os.Create("bar.html")
	bar.Render(f)
}

TODO

update go-echarts-asset

PS

• Apache ECharts upgrade to 5.0, I think It's time to upgrade go-echarts to v3.(no need a big upgrade, Apache ECharts has backward compatibility )

[chenjiandongx]

LGTM

[susiwen8]

@chenjiandongx just little reminder go-echarts-asset haven't update. TODO.