Area.svelte component

<!--
  @component
  Generates an SVG area shape using the `area` function from [d3-shape](https://github.com/d3/d3-shape).
 -->
<script>
  import { getContext } from 'svelte';

  const { data, xGet, yGet, xScale, yScale, extents } = getContext('LayerCake');

  /**  @type {String} [fill='#ab00d610'] The shape's fill color. This is technically optional because it comes with a default value but you'll likely want to replace it with your own color. */
  export let fill = '#ab00d610';

  $: path = 'M' + $data
    .map(d => {
      return $xGet(d) + ',' + $yGet(d);
    })
    .join('L');

  let area;

  $: {
    const yRange = $yScale.range();
    area = path + (
      'L' + $xScale($extents.x ? $extents.x[1] : 0) + ',' + yRange[0] +
      'L' + $xScale($extents.x ? $extents.x[0] : 0) + ',' + yRange[0] +
      'Z'
    );
  }
</script>

<path class='path-area' d='{area}' {fill}></path>