Available with Location Referencing license.
Routes are PolylineZM features that store measure values on their vertices to model linear distance. The measure values are stored on the vertices because, in many cases, the geometry of a feature is not as accurate as the measured lengths maintained for the feature. This can be the case for roads and other linear features. The routes maintain measures to support locating linear referenced events.
In the linear referencing system (LRS), the LRS editor associates centerline features to routes and provides measure inputs using tools to create or modify routes. The tools to create or modify route features also calculate and store the measure values on the route’s vertices. The centerlines are managed in a separate polyline feature class and are associated with routes by the tools in the centerline sequence table.
The centerline sequence table allows the same centerlines to be associated with different routes in the same LRS Network (as is the case with concurrent routes) or with routes in different LRS Networks. This allows you to use the same polyline geometry (centerline) to create different measure systems (route features). Examples of measure systems include continuous, state mile point, and county mile point, all of which can be built on the same centerlines.
It is important to note that only LRS editors need to work with centerline features to build and edit routes. Locating linear referenced events on routes or measure or spatial analysis on routes does not require centerlines. In addition, the LRS editor need not work with the centerline sequence table explicitly. The tools implicitly populate this table.
Centerline feature class
The centerline feature class is the geometry source from which routes are created. The table must include the CenterlineID field, the RouteID field, the NetworkID field, and FromDate and ToDate fields. The centerline feature class can be given a name that is appropriate to your business, but you may have only one centerline feature class per LRS.
Centerline sequence table
The centerline sequence table is a cross-reference table for the many-to-many relationships between centerlines and routes. The table must include the CenterlineID field, the RouteID field, the LRSNetworkID field, and FromDate and ToDate fields.