xyzshop/data/resource/mobile/qixi/js/point.js

function Point() {
  this.el = $('.item_game .points');
  this.classNames = ['point_1', 'point_2', 'point_3', 'point_4'];
  this.html = '';

  for(var i = 0; i < 20; i++) {
    this.html += this.create(i);
  }
  this.el.html(this.html);
}

Point.prototype = {
  getRandom: function(min, max) {
    return Math.round(Math.random() * (max - min) + min);
  },
  randomLeft: function() {
    return this.getRandom(260, 420);
  },
  randomIndex: function() {
    return this.getRandom(0, 3);
  },
  create: function(i) {
    var left = "left: " + this.randomLeft() + "px";
    var delay = "animation-delay:" + (i * 0.5).toFixed(2) + "s" ;
    var style = left + ";" + delay;
    var str = '<div class="' + this.classNames[this.randomIndex()] +  '" style="' + style + '"></div>'
    return str;
  }
}