////////////////////////////////////////////////////////////////////////////////////////////////////
/// <summary> Returns our estimate of the distance to nearest target from start node. </summary>
///
/// <remarks>
/// This is the classic computation for "dist from start" + "est dist to target" and forms the
/// heart of the A* algorithm.
/// </remarks>
///
/// <returns> Distance estimate. </returns>
////////////////////////////////////////////////////////////////////////////////////////////////////
private double DistToNearestTarget()
{
// This is the classic computation for <dist from start> + <est dist to target>
// and forms the heart of the A* algorithm
return(_distanceFromStart + _targets.Select(t => StateData.EstDistance(t)).Min());
}
