Function rotate

libraries/p5.js:30055–30059

(x, y, rad)

  var PI = Math.PI, _120 = PI * 120 / 180, f1, f2, cx, cy,
    rad = PI / 180 * (+angle || 0), res = [], xy,
    rotate = function (x, y, rad) {
      var X = x * Math.cos(rad) - y * Math.sin(rad),
        Y = x * Math.sin(rad) + y * Math.cos(rad);
      return { x: X, y: Y };
    };
  if (!recursive) {
    xy = rotate(x1, y1, -rad);
    x1 = xy.x;