The user shall not set from, to, via. Locus shall set to and from points according to the programming interface brouter offers.
The user shall set points in Locus as for other routing services.
Example: Route and measure: User defines four points p1, p2, p3, p4 and selects the routing profile.
Locus takes p1 and p2 and calls brouter with from=p1, to=p2 routing profile and gets back the calculated route1.
Then Locus calls brouter with from=p2, to=p3 and again gets back route2.
Then the same with p3, p4 and route3.
Locus concatenates route 1, 2, 3 and saves this as the result of route and measure.