雷达图的 line、area 在 smooth 的时候不重叠

[hustcc]

import { Chart } from '@antv/g2';

const chart = new Chart({
  container: 'container',
  height: 400,
});

chart.coordinate({ type: 'polar' });

chart
  .data([
    { item: 'Design', type: 'a', score: 70 },
    { item: 'Design', type: 'b', score: 30 },
    { item: 'Development', type: 'a', score: 60 },
    { item: 'Development', type: 'b', score: 70 },
    { item: 'Marketing', type: 'a', score: 50 },
    { item: 'Marketing', type: 'b', score: 60 },
    { item: 'Users', type: 'a', score: 40 },
    { item: 'Users', type: 'b', score: 50 },
    { item: 'Test', type: 'a', score: 60 },
    { item: 'Test', type: 'b', score: 70 },
    { item: 'Language', type: 'a', score: 70 },
    { item: 'Language', type: 'b', score: 50 },
    { item: 'Technology', type: 'a', score: 50 },
    { item: 'Technology', type: 'b', score: 40 },
    { item: 'Support', type: 'a', score: 30 },
    { item: 'Support', type: 'b', score: 40 },
    { item: 'Sales', type: 'a', score: 60 },
    { item: 'Sales', type: 'b', score: 40 },
    { item: 'UX', type: 'a', score: 50 },
    { item: 'UX', type: 'b', score: 60 },
  ])
  .scale('x', { padding: 0.5, align: 0 })
  .scale('y', { tickCount: 5 })
  .axis('x', { grid: true })
  .axis('y', { zIndex: 1, title: false });

chart
  .area()
  .encode('x', 'item')
  .encode('y', 'score')
  .encode('color', 'type')
  .encode('shape', 'smooth')
  .style('fillOpacity', 0.5);

chart
  .line()
  .encode('x', 'item')
  .encode('y', 'score')
  .encode('color', 'type')
  .encode('shape', 'smooth')
  .style('lineWidth', 2);

chart.render();