/**
 * Swap page x and y when screen orientation is portrait.
 * Method: 
 * pageX = pageY
 * pageY = -pageX
 * @param e
 * @returns {[{pageY, pageX}]}
 */
getTouches(e) {
  const isPortrait = window.matchMedia('(orientation: portrait)').matches;
  const touches = [
    {
      pageX: e.touches[0].pageX,
      pageY: e.touches[0].pageY,
    },
  ];
  if (isPortrait) {
    [touches[0].pageX, touches[0].pageY] = [
      touches[0].pageY,
      -touches[0].pageX,
    ];
  }
  return touches;
},