Poutnik the Wanderer <[email protected]> writes: > If the value is higher than the average way cost per straight line length, > It becomes very fast and wrong. As it starts to prefer route > evaluations with their progress getting the closest to the > destination, with less caring about the cost. > > Statistically, if all roads have ideal 1.0 rating, > ratio of way cost(=way length) / straight line length is 1.2-1.3, > given by the average way prolonging because of curvature. > > So 1.4 is still quite safe, > because ways are not ideal and have their average rating >1.0.
Thanks to you and Harry for a very clear explanation! It made me think of something else I don't quite follow: You are talking about 1.0 for ideal, and as I see the world there is no ideal way, just ways with different speeds. So is there some assumed max speed that the 1.0 or 1.4 rating is realtive to? As in 1.0 would correspond to a straight motorway from the in-process route point to the destination? I wonder, if the developers are unwilling to change the heuristic by default, if the UI could simply have a value for it in an advanced menu. An alternative would be to bump it up automatically when route calculation takes too long, and remember heuristic by distance bin. -- You received this message because you are subscribed to the Google Groups "Osmand" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
