SegmentGeoPoint
Describes the geographic point on the segment and the direction of the segment. Route geometry is a sequence of points that form segments in pairs. All functions working with route geometry consider that the first point of the pair forming the segment is included in this segment, and the second point is not: [point_1, point_2),[point_2, point_3),...,[point_n-1, point_n)[point_last]. The last point forms a segment of zero length with itself. Thus, each point of the path belongs to exactly one segment. The direction of point_last is undefined.