Abstract
This research paper proposes a new method for smoothing polylines on a map, using B-splines iteratively moving away from the vertices. Splines are a popular tool used to smooth data. Unfortunately, natural objects represented by polylines, usually have an irregular shape and unevenly spaced vertices. For such data, splines may have a distorted course. The presented method changes an approach to polylines on the map. The smoothed line is no longer just a line connecting a set of vertices on the map but becomes a path that a hypothetical hiker must follow. The hiker attempts to optimise (simplify) the route so that, it requires the least amount of effort. The hiker will therefore avoid the vertices at a certain distance, leaving dense and even traces. These traces constitute a data set for which the unfavourable properties of splines are eliminated. The vertices of the polyline will be smoothed (bypassed) by the B-spline control point function, which, spread over a dense set of tracks, will perform the first, slight smoothing. Subsequent smoothing iterations will be performed on a modified, increasingly sparse, but still uniform set of traces from the previous iterations. This will allow for even smoothing of any polyline.