# Polyline to PolyArc

![](https://1430428134-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-Ld8QK19sjP1I9rhLouo%2F-MZM7SZkt5hXIu_8tiT4%2F-MZM8B-7yI76iwntO7iT%2FoffsetPolyLineAsPolyarc.png?alt=media\&token=bfcc7087-ded3-488b-9148-bb4fd6c4da27)

```d
def lnToAr(pl:var[]..[], of:double)
{
	pc1 = List.FirstItem(pl.Curves());
	//First Arc
	ac1 = List.FirstItem(pc1);
	ac2 = ac1.Offset(of).PointAtParameter(0.5);
	ar1 = Arc.ByThreePoints(ac1.StartPoint,ac2,ac1.EndPoint);
	ac3 = List.RestOfItems(pc1);

	ar5 = [Imperative]
	{
		cnt = 1;
		pc2 = [ar1];

		for (cr in ac3)
		{
			pc2[cnt] = Arc.ByStartPointEndPointStartTangent(cr.StartPoint,cr.EndPoint,ar1.TangentAtParameter(1));
			ar1 = pc2[cnt];
			cnt = cnt + 1;
		}
		return pc2;
	}
	return ar5;
```