Anchor Types

Attribution is associated with road segments as described in the following anchor types:

Segment directionality is published to identify in which segment direction the specific attribute applies. Forward segment direction is defined as the direction from the segment start node to the segment end node.

This attribute applies to the whole segment in both directions.

For example, access characteristics of a segment (AccessAttribute) identify which vehicles are allowed on the specific road segment, and apply to the whole segment regardless of the direction of travel.

This attribute applies to the whole segment in one direction only. In this case, only in the forward direction.

For example, the lane count (LaneCountAttribute) of a given segment applies to the whole segment and is specified based on the segment direction, as lane count might be different per segment side.

In this situation the attribute applies only to a subset of the segment. The sub-segment is identified by a Start and an End Offset. Therefore, the attribute applies only to the portion of the segment identified by the start and end ranges.

For example, a functional class value (FunctionalClasssAttribute) might vary along a segment. The example in the following illustration represents a Functional Class value applicable on the sub-segment identified by the Start and End Offsets in both segment directions.

The attribute applies to the segment starting from a specific offset and in one direction only.

For example, a traffic light is located along the segment at an offset identified by a red dot. The red arrows indicate in which segment direction the traffic light applies to.

This attribute applies to segment A and segment B in the forward direction, implying a condition, such as a restriction, that applies going from one segment to the other.

For example, the condition going from segment A to B represented in the following figure is a gate, restricting access from segment A to segment B.

This attribute applies to a segment node.

For example, an elevation value is associated to a segment of a node.

The following table identifies attributes, their anchor type, and the associated possible segment direction combinations.