CODEWITHSUNDEEP
iosswiftmapboxmapbox-gldirections
113408
113408

Reputation: 3444

Avoid coordinates when generating a route using Mapbox Direction API

I have been using Mapbox for my app to generate route and turn-by-turn navigation and it's working well. However I would like to avoid to go through some coordinates of the route but I can't figure it out.

The code to get the route :

Directions.shared.calculate(options) { [unowned self] (waypoints, routes, error) in
        // Take first route and customize it in a way to get around some coordinates
    }

Here is a scenario :

1- User location is latitude = 37.332331410000002, longitude = -122.0312186

2- The user is going to Santa Clara Unified School located on latitude = 37.354100000000003,longitude = -121.9552

3- The Api generates the following route :

 [0] = {
latitude = 37.332329999999999
longitude = -122.03118000000001
}
  [1] = {
    latitude = 37.332619999999999
    longitude = -122.03118000000001
  }
  [2] = {
    latitude = 37.332609999999995
    longitude = -122.03097000000001
  }
  [3] = {
    latitude = 37.332609999999995
    longitude = -122.03076000000001
  }
  [4] = {
    latitude = 37.332199999999993
    longitude = -122.03076000000001
  }
  [5] = {
    latitude = 37.331689999999995
    longitude = -122.03076000000001
  }
  [6] = {
    latitude = 37.331689999999995
    longitude = -122.03190000000002
  }
  [7] = {
    latitude = 37.331719999999997
    longitude = -122.03199000000002
  }
  [8] = {
    latitude = 37.331759999999996
    longitude = -122.03205000000003
  } ...

4- Suppose the generated route goes through East Homestead Rd, I would like to be able to avoid this road and generate a new route even if it's a longer one.In the screen below avoid the route in red because going through East Homestead Rd and take the next fastest route not going through East Homestead Rd enter image description here

Any help would be appreciated !

EDIT : Here is the query for finding if a route has points to avoid in it

// $linestring is the array of coordinates from the route in the string format of (lng lat,lng2 lat2,lng3 lat3,lng4 lat4....)
$query = $this->em->createQuery('
            SELECT   count(i) as counter
            FROM     HitsBundle:Hit i
            WHERE i.datetime BETWEEN :lastMonth AND :now 
                  AND 
                  MBRCovers(
                    ST_Buffer( 
                        ST_GeomFromText(\'LineString('.$linestring.')\') ,
                        0.00001
                    ),
                    i.coordinates
                  ) = 1
            GROUP BY i.coordinates
            HAVING  counter > 1
        ')
            ->setParameter('lastMonth', $lastMonth)
            ->setParameter('now', new \DateTime())
            ->setMaxResults(1);

EDIT: Related issue on Github

Upvotes: 6

Views: 2723

Answers (2)

113408
113408

Reputation: 3444

After few months dealing with the MapBox Direction API we've come to the conclusion that it's not reliable for this specific use case. When calculating routes from Point A to Point B using the Direction API, MapBox offers an option includesAlternativeRoutes if set to true it provides alternative routes. However this is not consistent and in most cases it returns only the preferred route.

According to MapBox :

If the value of this property is true, the server attempts to find additional reasonable routes that visit the waypoints. Regardless, multiple routes are only returned if it is possible to visit the waypoints by a different route without significantly increasing the distance or travel time.

So we will switch to Google Maps as this feature is crucial to our business logic.

Upvotes: 0

gp42
gp42

Reputation: 545

I may be rough-guessing here, but looking through Mapbox API it does not have any options to avoid while generating routes, therefore you need to implement some route-selection logic on client-side.

Basically you need to have an algorithm which gets a set of points to avoid and checks if your Route geometry GeoJSON or Polyline are within some threshold range from given points. If it is - discard the route (or lower route priority).

Of course it may fail to find a route if all routes provided by Mapbox are discarded - Mapbox does not know about your restrictions, therefore using weight for routes could be one option of solving this.

These posts might give you some hints:

Upvotes: 3

Related Questions