function linearRingContainsXY(
  flatCoordinates,
  offset,
  end,
  stride,
  x,
  y,
) {
  // https://web.archive.org/web/20210504233957/http://geomalgorithms.com/a03-_inclusion.html
  // Copyright 2000 softSurfer, 2012 Dan Sunday
  // This code may be freely used and modified for any purpose
  // providing that this copyright notice is included with it.
  // SoftSurfer makes no warranty for this code, and cannot be held
  // liable for any real or imagined damage resulting from its use.
  // Users of this code must verify correctness for their application.
  let wn = 0;
  let x1 = flatCoordinates[end - stride];
  let y1 = flatCoordinates[end - stride + 1];
  for (; offset < end; offset += stride) {
    const x2 = flatCoordinates[offset];
    const y2 = flatCoordinates[offset + 1];
    if (y1 <= y) {
      if (y2 > y && (x2 - x1) * (y - y1) - (x - x1) * (y2 - y1) > 0) {
        wn++;
      }
    } else if (y2 <= y && (x2 - x1) * (y - y1) - (x - x1) * (y2 - y1) < 0) {
      wn--;
    }
    x1 = x2;
    y1 = y2;
  }
  return wn !== 0;
}
@param {Array<number>} flatCoordinates Flat coordinates.
@param {number} offset Offset.
@param {number} end End.
@param {number} stride Stride.
@param {number} x X.
@param {number} y Y.
@return {boolean} Contains (x, y).