Specifications

General

heading

track point heading

The heading of a track point is the nautical or geographical azimuth, the clockwise in degrees measured angle between the north and the heading direction.

Fig. 38 Heading

street segment origin ID

To a street segment corresponding ID from the original data source.

street segment origin offset

It can be necessary to split a street given by a data source into multiple street segments, e.g. because of junctions. We explain the idea of the offset by the following example.

Fig. 39 Original street map

By splitting the original street segment 3 at the junctions with the original street segments 1 and 2 we created three street segments corresponding to the original street segment 3, all starting at a different offset.

Fig. 40 Created street segments

In the end we have (street ID, offset) tuples. Such a tuple defines the beginning of a street segment. While the end of the street segment can be reconstructed implicit by adding the coordinate count of the street segment to the offset.