Offset polyline with Clipper

I am using the Clipper library, which is quite easy to do polygonal displacement, BUT MY PROBLEM IS ONLY TO PERFORM POLYLAN, preferably using Clipper.

While searching on the internet, I found a function named OffsetPaths

, but the function is biased, i.e. only a positive argument is required as the offset distance.

I can understand that unlike closed polygons, where it is easy to indicate direction by magnifying positive and deflating as negative, polylines do not have the same luxury. But this is my demand.