echarts拐点样式修改

echarts的拐点可以是'circle', 'rect', 'roundRect', 'triangle', 'diamond', 'pin', 'arrow', 'none'

还可以是'image://url'

如果是svg. 那么可以这么展示：

option = {
  xAxis: {
    type: 'category',
    data: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
  },
  yAxis: {
    type: 'value'
  },
  series: [
    {
      data: [120, 200, 150, 80, 70, 110, 130],
      type: 'line',
      symbol: 'path://M170.688 128h682.624c23.616 0 42.688 19.072 42.688 42.688v682.624a42.688 42.688 0 0 1-42.688 42.688H170.688A42.688 42.688 0 0 1 128 853.312V170.688C128 147.072 147.072 128 170.688 128z m42.624 85.312v597.376h597.376V213.312H213.312z',
      symbolSize: 20,
      lineStyle: {
        color: '#5470C6',
        width: 1,
        type: 'solid'
      },
      itemStyle: {
        borderWidth: 3,
        borderColor: '#EE6666',
        color: 'yellow'
      }
    }
  ]
};