Use of imported .gpx files
  • I was surprised today by a 'fastest' route chosen by Navigator FREE.  I have tried to force it to take another route by introducing waypoints, without success.  AA, Google Maps, OSRM and RAC, while not all taking the same route precisely, produce routes of no more than 19.3 miles.  I have looked at OSM data in JOSM and there does not seem to be a reason for Navigator FREE to avoid the route I would take but drives me eight miles further in a longer time.  I do hope this is a rare aberration.  My question, however, is this: is it possible, in the light of what I have written, to import a .gpx file that is a route of my choice and navigate to that route?
    The coordinates, if anyone is interested, are start = 51.50085, -0.92511; destination = 51.31118, -1.08518.
  • 6 Comments sorted by
  • with TomTom maps I get 18 miles with default car settings
    with OSM I need to switch small local roads on in settings/vehicle profiles/car/road restriction to get 18 miles

  • tomas
    I thank you for your prompt reply.  'Small Local Road' was not switched on, indeed.  Navigator matches OSRM when it is on.  The route chosen remains something of a mystery, however, because the straightforward route, on better classes of road, would proceed directly to the roundabout at 51.31678, -1.024569.  I guess it all comes down to the speeds allocated to all the links involved.
    Incidentally, I do not understand 'Preference' and 'Use speed restrictions' yet in ROAD RESTRICTIONS.  Would you explain, please, or refer me to an explanation?  And is it unwise for users in general to fiddle with 'Extraurban' and 'Urban' speed values?
  • I always recommend to leave it in default
    if you untick Use speed restrictions, then speed restrictions will be ignored - routing may choose 30mph road where it would not with speed restrictions on
    preference is to set preferred type of road, e.g. motorways
  • "Turn on Small local roads"


    I've heard that advice from tomas and PrzemekSupak given
    several times to newbies in the past  2 months or so myself included  They must
    get tired of saying it

    Why does Navigator Free by default not switch it on anyway?  I
    suspect there may be people who download from Playstore do a short local route
    as a trial and get a poor route so bin NF without giving it a rating  Only some
    will persist and perhaps come to the forum


    Of the 9 road categories in NF (1=Motorway 9=Other roads)
    Small local roads(=8) appears to include the OSM "unclassified" and
    "residential" roads which in most rural and urban areas are the only roads
    available to leave the start point and access a destination   So obviously NF in
    the default set-up selects some strange routes

    In silvermapper's route some roads are rural 60mph roads that
    are neglected by NF because they are 8th order Small local roads - in fact these
    ones are important local link roads  They are Local roads at the very least -
    perhaps they should be selected as such by maxspeed?

    Tomas says that Tomtom selected the right route first
      OSRM did it too   That can only mean that these route
    selectors are smarter some way  - or the road categories are handled

    This is a topic I see has been well discussed in the past



    However I've never seen a really good explanation by NF people
    about the reason for retaining the large number of road categories  Perhaps I've
    just missed the thread somewhere?

  • W.r.t. the "small local roads": It's mentioned in way more topics and lately again by me here. So yes, I fully agree with you that they should be switched on by default.

    W.r.t. to the number of road categories: That has not been chosen by MapFactor. It is how OSM is setup, equally for TomTom. 
    Also look at a "normal" paper map: If you look at the legend of the map you also see a lot of road types.

  • hvdwolf

    Thanks for your comments
    On road categories/classification
    My use of the term "category" has perhaps been misleading I agree that the classification (primary, residential etc) for each road comes from OSM In my link#1 above mdx listed the OSM classifications:
    mdx August 2014
    well, yes I am avoiding this topic . I think that wrote somewhere currently used conversions:
    dict = {
    'motorway': (0,130),
    'motorway_link': (0,110),
    'trunk': (1,110),
    'trunk_link': (2,90),
    'primary': (3,90),
    'primary_link': (3,80)
    There are around 18 road types in the list that can be used by motor vehicle And mdx indicates that MF has put these in 9 groups (0 to 8) which match the 9 road categories in the vehicle profile The top 8 groups have speed and preference numerical settings that can be adjusted by the user All of this gives an impression that the algorithm that selects a route and makes a time estimate is probably fairly refined However all the postings on route selections and time to destination suggest the impression is not totally correct
    Having played with the speed and preference settings in the NF app I consider that reducing the 9 road groups/categories to a smaller number like 5 or 6 will have very little detrimental effect on route selection but have the advantage of simplification for the user
    As an example below If we take hvdwolf settings as in my link#1 local conn and lcl rd oh imp are the same any way Then combine/average primary and major (these are trunk and trunk link) and we have reduced to 7 - we are almost there without even trying and likely little or no effect on route selections And time estimates were already quite bad

    default MFNF mine (hvdwolf)

    motorway 130 80 50 110 70 70
    primary 90 50 50 90 50 65
    major 85 50 50 80 50 60
    secondary 80 50 50 70 50 50
    local conn 70 50 50 60 50 50
    lcl rd oh imp 60 50 50 60 50 50
    local road 60 40 50 50 40 50

    Having said all that I note in the mdx list there are different speeds for roads in the same road group How does all this work with user-set speed settings as in the app?
    For the future I would like to think that improvements will somehow provide better time estimates based on smarter use of maxspeed (where listed) urban/ex-urban road location and time-of day and day-of-week data
    Sympathies to poor developers who still have a great basic app!

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