This is already a discussion running since 2012 (or so). At that time
Victor decided to go use a heuristic coefficient of 1.0 for car navigation.
This makes the calculations extremely slow and requiring a huge load of
memory. Hence the fact that you can't calculate longer routes.

On my 2GB phone and 2GB android head unit (in my car) I can calculate
routes to 400-500 km.
Using a heuristic coefficient of 1.4 in Osmand, i can easily calculate
routes >1400 km AND faster then the original route of 400-500 km with a HC
value of 1.0

90% of the nav-apps use the A* algorithm, with or without some tweaks. Most
use it with an HC between 1.3 -1.5.
OsmAnd is the only one using 1.0 to always calculate the 100% optimal route.

This is of course overkill, and not true either as a theoretical approach
is never 100% correct in practice (, if only due to incorrect/incomplete
tagging of roads). On long routes you drive 95% on motorways and 5% on
secondary or city roads. The first and last 10 minutes, would in that case
perhaps  be12 minutes on a full day trip. so what?
On smaller routes in cities it is not worth it either. We all know that
waiting for a traffic light might take more time than a slightly longer
parallel road, and when the traffic light is green, you are lucky.

All nav-app builders use this pragmatic, common-sense approach for route
calculation except OsmAnd.

last weeks this was also discussed with examples. Simply search for
heuristic coefficient.

Harry

Op wo 10 apr. 2019 om 08:50 schreef Poutnik Fornntp <[email protected]
>:

> The best route does not exist. More exactly, there is almost as many best
> routes as is the number of the different criteria how to evaluate routes.
>
> Therefore one cannot expect OsmAnd best route must match your best route.
>
> I will not speak about speed of route calculation, that has a lot of space
> for improvement even in context of the used A-star routing algorithm (e.g.
> search the group history about setting the heuristic coefficient)
>
> I do not speak for OsmAnd, using rather dedicated car navigating apps and
> LocusMap for biking/hiking.
>
>
> Dne 10. dubna 2019 7:08:05 alpine14011970 <[email protected]>
> napsal:
>
> > What is the use of a navigation where I want the route to be best chosen
> > for me, yet now we have to choose waypoints so that the routes can
> > calculate my route. The route should be chosen by Osmand maps better
> than I
> > can and quicker than I can do.  It is time consuming and difficult to
> know
> > which direction to choose and calculate routes without never have heen
> > there before. I raced both my Samsung Galaxy tab S2 and my Galaxy S8
> plus,
> > calculating the exact same route, the tab S2 won, while my Galaxy S8plus
> > just hung there.
>
>
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