; (function ($) {
  $.path = {};
  var V = {
    rotate: function (p, degrees) {
      var radians = degrees * 3.141592654 / 180
      var c = Math.cos(radians), s = Math.sin(radians)
      return [c * p[0] - s * p[1], s * p[0] + c * p[1]]
    },
    scale: function (p, n) { return [n * p[0], n * p[1]] },
    add: function (a, b) { return [a[0] + b[0], a[1] + b[1]] },
    minus: function (a, b) { return [a[0] - b[0], a[1] - b[1]] }
  }
  $.path.bezier = function (params) {
    params.start = $.extend({ angle: 0, length: 0.3333 }, params.start);
    params.end = $.extend({ angle: 0, length: 0.3333 }, params.end);
    this.p1 = [params.start.x, params.start.y];
    this.p4 = [params.end.x, params.end.y];
    var v14 = V.minus(this.p4, this.p1);
    var v12 = V.scale(v14, params.start.length);
    v12 = V.rotate(v12, params.start.angle);
    this.p2 = V.add(this.p1, v12);
    var v41 = V.scale(v14, -1);
    var v43 = V.scale(v41, params.end.length);
    v43 = V.rotate(v43, params.end.angle);
    this.p3 = V.add(this.p4, v43);
    this.f1 = function (t) { return (t * t * t); }
    this.f2 = function (t) { return (3 * t * t * (1 - t)); }
    this.f3 = function (t) { return (3 * t * (1 - t) * (1 - t)); }
    this.f4 = function (t) { return ((1 - t) * (1 - t) * (1 - t)); }
    /* p from 0 to 1 */
    this.css = function (p) {
      var f1 = this.f1(p), f2 = this.f2(p), f3 = this.f3(p), f4 = this.f4(p);
      var x = this.p1[0] * f1 + this.p2[0] * f2 + this.p3[0] * f3 + this.p4[0] * f4;
      var y = this.p1[1] * f1 + this.p2[1] * f2 + this.p3[1] * f3 + this.p4[1] * f4;
      return { top: y + "px", left: x + "px" };
    }
  }
  $.path.arc = function (params) {
    for (var i in params) this[i] = params[i];
    this.dir = this.dir || 1;
    //while (this.start >= this.end && this.dir > 0) this.start -= 360
    //while (this.start <= this.end && this.dir < 0) this.start += 360
    this.css = function (p) {
      var a = this.start * (p) + this.end * (1 - (p));
      a = a * 3.1415927 / 180; // to radians
      var x = Math.sin(a) * this.radius + this.center[0];
      var y = Math.cos(a) * this.radius + this.center[1];
      return { top: y + "px", left: x + "px" };
    }
  }
  $.path.circle_arc = function (params) {
    for (var i in params) this[i] = params[i];
    this.dir = this.dir || 1;
    this.end = this.start + (this.dir * 360);
    this.css = function (p) {
      var a = this.start * (p) + this.end * (1 - (p));
      a = a * 3.1415927 / 180; // to radians
      var x = Math.sin(a) * this.radius + this.radius;
      var y = Math.cos(a) * this.radius + this.radius;
      return { top: y + "px", left: x + "px" };
    }
  }
  $.fx.step.path = function (fx) {
    var css = fx.end.css(1 - fx.pos);
    for (var i in css) fx.elem.style[i] = css[i];
  }
})(jQuery);