Abstract
Feature lines of an object represent its surface characteristics along a specific plane or direction. They are essential for understanding and analysing the object's shape, geometry, and features. Depending upon the details stored in an object or data, feature line extraction can be a complex task. In terrain data, these details can be slopes for ridges and valleys, artefacts or some other forms of noise. If the data for analysis consists of point clouds with only positional values, one of the most common methods to detect patterns is to rely on the Euclidean distance between neighbouring points. In this paper, a method to extract terrain feature lines on point clouds has been presented that relies only on coordinate values. The feature line points are initially identified with the help of a projection of point clouds on 2D grids, and then these are used to extract feature lines or breaklines with the help of a spanning tree algorithm. The method can generate output with high accuracy for data with less noise and moderate accuracy for data with more noise.