Topological arc layers

In addition to the topological metadata information, a topological arc layer must contain the following attributes:

• StartNodeId: Contains the GDBShapeId of the starting node.
• EndNodeId: Contains the GDBShapeId of the ending node for this arc.
• LeftAreaId: Contains the GDBShapeId of the left-area polygon or GDBNullShapeId if there is no such area.
• RightAreaId: Contains the GDBShapeId of the right-area polygon or GDBNullShapeId if there is no such area.

An arc must have at least two vertices.

An arc layer must have NODE_REF and AREA_REF metadata that points to the related node and area layers. It must also have a LAYER_TYPE of TOPO_ARCS indicator in metadata.