Function getDistance

docs/tests/v2/es6/js/sanddance.js:52084–52092

* calculate the absolute distance between two points * @param {Object} p1 {x, y} * @param {Object} p2 {x, y} * @param {Array} [props] containing x and y keys * @return {Number} distance

(p1, p2, props)

  function getDistance(p1, p2, props) {
    if (!props) {
      props = PROPS_XY;
    }

    var x = p2[props[0]] - p1[props[0]],
        y = p2[props[1]] - p1[props[1]];
    return Math.sqrt(x * x + y * y);
  }
  /**
   * calculate the angle between two coordinates
   * @param {Object} p1