src/index.js
function polygonAt(polygon, i){
    var s = polygon.length;
    return polygon[i < 0 ? i % s + s : i % s];
}
function polygonAt(polygon, i){
    var s = polygon.length;
    return polygon[i < 0 ? i % s + s : i % s];
}
function polygonAt ( polygon , i ) { var s = polygon . length ; return polygon [ i < 0 ? i % s + s : i % s ] ; }
Get a vertex at position i. It does not matter if i is out of bounds, this function will just cycle.
@method at
@param  {Number} i
@return {Array}
Get a vertex at position i . It does not matter if i is out of bounds this function will just cycle .