Circumference = function (ellipse)
{
    var rx = ellipse.width / 2;
    var ry = ellipse.height / 2;
    var h = Math.pow((rx - ry), 2) / Math.pow((rx + ry), 2);

    return (Math.PI * (rx + ry)) * (1 + ((3 * h) / (10 + Math.sqrt(4 - (3 * h)))));
}
Returns the circumference of the given Ellipse.

@function Phaser.Geom.Ellipse.Circumference
@since 3.0.0

@param {Phaser.Geom.Ellipse} ellipse - The Ellipse to get the circumference of.

@return {number} The circumference of th Ellipse.