Calculate the distance between two points

/**
 * This function will calculate the distance between two provided points.
 * This is useful in game development when calculating paths of motion for sprites.
 * The function expects two points to be provided. A point is defined as an object
 * with an "x" and a "y" property. The result is a numeric value of the distance.

 * @param {Number} point1
 * @param {Number} point2

 * @returns Number The result is a numeric value of the distance.
 * @type Number
 */
function lineDistance(point1, point2) {
  var xs = 0;
  var ys = 0;

  xs = point2.x - point1.x;
  xs = xs * xs;

  ys = point2.y - point1.y;
  ys = ys * ys;

  return Math.sqrt(xs + ys);
}