Adjust routing preferences

Route calculations (including rerouting) return the route that takes the least amount of time to navigate as the default best route. But you can change the routing strategy so that the shorter of the route alternatives is returned instead.

The term shorter means the route that is the shortest among optimal route based on our default cost model. The shorter route might not be the absolute shortest route, since that option might be a poor alternative. For example, if the absolute shortest route is 10 km and takes 50 minutes to navigate and another route is 15 km, but only takes 20 minutes to navigate, the second choice is optimal, because spending 30 mins to reduce five km isn't a good trade-off.

Once you set the routing strategy for a trip, it won't change until the trip completes. To change the routing strategy for an existing trip, you must clear the destinations and reset them again with the new routing strategy.

Note: The feature mentioned above is intended for Rideshare providers that operate in regulated markets (such as Europe), who are often required by law to price their services based on the same principles as traditional taxis—which charge based primarily on the distance traveled.

Getting route details

To determine which route strategy is the optimal choice for a given waypoint, call getRouteInfoForDestination() to get route details for both the default best route and the absolute shorter route. Details include the duration and the distance to a destination waypoint.

These details come from GMSNavigationRouteInfo in the callback.

Example

The following code example demonstrates how to get route details for each of the two routing strategies.

Swift

let routingOptions = GMSNavigationRoutingOptions()
navigator?.getRouteInfoForDestination(destination,
                                      routingOptions: routingOptions) { routeInfo in
  ...
}

Objective-C

GMSNavigationRoutingOptions *routingOptions =
    [[GMSNavigationRoutingOptions alloc] init];
[navigator getRouteInfoForDestination:destination
                   withRoutingOptions:routingOptions
                             callback:^(GMSNavigationRouteInfo *routeInfo){...}];

Setting the routing strategy

You can configure the routing strategy by using GMSNavigationRoutingOptions, and setting the routingStrategy when calling setDestinations().

routingStrategy takes one of the following enumeration values:

Enumeration Value	Description
GMSNavigationRoutingStrategyDefaultBest	Ranks routes by the Navigation SDK default cost model. This is the default routing strategy.
GMSNavigationRoutingStrategyShorter	Ranks routes by distance. The highest ranking route is the shortest of those returned.

Warning: This feature is incompatible with the Hiding Alternate Route feature. Using these two features at the same time will produce unexpected results.

Example

The following code example demonstrates how to set the shorter route routing strategy.

Swift

let routingOptions = GMSNavigationRoutingOptions(routingStrategy: .shorter)
navigator?.setDestinations(destinations,
                           routingOptions: routingOptions) { routeStatus in
  ...
}

Objective-C

GMSNavigationRoutingOptions *routingOptions = [[GMSNavigationRoutingOptions alloc] initWithRoutingStrategy:GMSNavigationRoutingStrategyShorter];
[navigator setDestinations:destinations
            routingOptions:routingOptions
                  callback:^(GMSRouteStatus routeStatus){...}];

Routes that include ferries

By default, the Navigation SDK for iOS excludes routes that include ferries. If you prefer to include ferry options as part of your routes, you can adjust this routing preference to expose the trip to ferry segments by setting avoidsFerries to false.

Example

Swift

self.mapView.navigator?.avoidsFerries = false

Objective-C

self.mapView.navigator.avoidsFerries = NO

The route callout format

Under the shorter route routing strategy, callouts along the route display distance details. But you can use the ETA callouts instead.

Configuring the route callout format

You can change the route callout format by setting routeCalloutFormat in GMSMapView. routeCalloutFormat takes one of the following enumeration values:

Enumeration Value	Description
GMSNavigationRouteCalloutFormatDefault	Displays time remaining when using the default best route routing strategy. Displays distance remaining when using the shorter route routing strategy
GMSNavigationRouteCalloutFormatTime	Displays time remaining.
GMSNavigationRouteCalloutFormatDistance	DDisplays distance remaining.

Example

The following code example demonstrates how to configure the route callout format.

Swift

self.mapView.routeCalloutFormat = .time

Objective-C

_mapView.routeCalloutFormat = GMSNavigationRouteCalloutFormatTime;