[Bug]: LocationMatching return delay, time uncertain

[iOSQiaoBusi]

Mapbox Navigation SDK version

The version of Mapbox I am using is Map: 11.25.0, Navigation: 3.25.0, Search: 2.25.0

Steps to reproduce

The version of Mapbox I am using is Map: 11.25.0, Navigation: 3.25.0, Search: 2.25.0. After initiating real navigation, I found that self. mapboxNavigation? .navigation().routeProgress
.sink { status in
let matching = self.mapboxNavigation? .navigation().currentLocationMatching
print("routeProgress: (status != nil), locationMatching: (matching != nil)")
// . ..
}The callback surface of. store (in:&cancellable) will show that after real navigation is enabled, locationMatching is nil. After a period of time (time is not fixed, a few seconds for fast navigation and a few minutes for slow navigation), it returns a value. Is this related to GPS positioning? Or is it related to the internet? Is there any way to deal with this return delay?

Expected behavior

The version of Mapbox I am using is Map: 11.25.0, Navigation: 3.25.0, Search: 2.25.0. After initiating real navigation, I found that self. mapboxNavigation? .navigation().routeProgress
.sink { status in
let matching = self.mapboxNavigation? .navigation().currentLocationMatching
print("routeProgress: (status != nil), locationMatching: (matching != nil)")
// . ..
}The callback surface of. store (in:&cancellable) will show that after real navigation is enabled, locationMatching is nil. After a period of time (time is not fixed, a few seconds for fast navigation and a few minutes for slow navigation), it returns a value. Is this related to GPS positioning? Or is it related to the internet? Is there any way to deal with this return delay?

Actual behavior

The version of Mapbox I am using is Map: 11.25.0, Navigation: 3.25.0, Search: 2.25.0. After initiating real navigation, I found that self. mapboxNavigation? .navigation().routeProgress
.sink { status in
let matching = self.mapboxNavigation? .navigation().currentLocationMatching
print("routeProgress: (status != nil), locationMatching: (matching != nil)")
// . ..
}The callback surface of. store (in:&cancellable) will show that after real navigation is enabled, locationMatching is nil. After a period of time (time is not fixed, a few seconds for fast navigation and a few minutes for slow navigation), it returns a value. Is this related to GPS positioning? Or is it related to the internet? Is there any way to deal with this return delay?

Is this a one-time issue or a repeatable issue?

one-time

[iOSQiaoBusi]

Once locationMatching is nil, I find that all navigation information is not returned, and the funcnavigationViewController（
_ navigationViewController: MapboxNavigationUIKit.NavigationViewController,
didUpdate progress: MapboxNavigationCore.RouteProgress,
with location: CLLocation,
rawLocation: CLLocation
）The proxy callback is not executed. What is the reason for this? Theoretically, after the route is planned, the proxy callback should be executed. Wow

[ArtemStepuk]

Hi @iOSQiaoBusi, thanks for the report.

currentLocationMatching is expected to be nil until the navigator has processed at least one location update.

To receive map-matching updates you need an active session: either active guidance (startActiveGuidance) or free drive (startFreeDrive). Once that session is running and the system receives a location, the SDK processes it and emits on the locationMatching stream.

Could you please double-check that the system is emitting location updates? A short delay of a few seconds while waiting for the first GPS fix is normal; a multi-minute delay is not expected. If you still see a long delay, could you share whether this is on a real device outdoors/indoors or the simulator, whether free drive is started before active guidance, and approximate delay / how consistently it reproduces?

[kried]

Hi @iOSQiaoBusi

I can add that a small amount of time is expected to be needed to map-match the current location to the known road network.This is why, even after the system provides a location update, the locationMatching publishes an event only after that location has been processed.

[iOSQiaoBusi]

Thank you for your help. I found that setting utilizeSensorData to false in CoreConfig at the beginning of navigation can increase the probability of successful locationMatching in real navigation, thereby enabling navigation and significantly reducing waiting time. My problem will be greatly improved. I would like to ask what this parameter mainly affects? Increase the efficiency of sensors/GPS?