# 2.2.4.1 Computing Dynamic Elevations

Elevations of Tracks are computed in following steps. The colors listed in each step are used as the background color of the Track Elevation Markers (if they are enabled (Section 2.10.3)).

- The Shortest Paths between all Defined Elevations are computed. A Path stops at Ignored or Defined endpoints. The Elevation of any Turnouts on these Paths with more than two connections are computed as the average Elevation inversely weighted by distance along the tracks to the Defined Elevation points (Blue).

- The Elevation of any other tracks on the Shortest Paths are computed based on the distance along the tracks from the Turnouts computed in the first step and/or the Defined Elevation points (Purple).

- The Elevation of any remaining tracks is computed based on the average Elevation of the tracks found in the first two steps that they are (directly or indirectly) connected to, inversely weighted by geometric distance (Gold).

- Any remaining tracks are not connected to a Defined Elevation and do not have an Elevation.

The elevation computation is performed incrementally every time the layout is changed to keep all elevations in sync. The performance of the computation is affected by the placement of the Defined Elevation endpoints and the number of Paths between them. Place the Defined Elevations at points where tracks begin to branch (such as the throat of a yard or at the ends of a siding). Also, use Defined Elevations to break the layout into areas so recomputation has fewer tracks and Paths to deal with.