Navigation viewport camera

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Navigation viewport camera system is a set of APIs, that allow developers to combine full-screen navigation experiences with UI overlays and animate the map through changing location-related data. The viewport is defined by edge insets that allow the user to frame important features on the map in areas of the screen that don’t conflict with UI elements.

By default navigation viewport camera allows control of camera viewport system frames based on various properties, such as current location, some or all of the remaining route line coordinates, upcoming maneuvers, etc. It provides a camera viewport system, which is optimal for visualization and animation in navigation applications.

The navigation viewport camera is also customizable, it allows you to change certain camera-related options if the need arises.

Navigation viewport camera APIs are available both on iOS (when using NavigationMapView or NavigationViewController) and on CarPlay (when using CarPlayMapViewController or CarPlayNavigationViewController).

How to use navigation viewport camera

Navigation viewport camera functionality is exposed via NavigationMapView.navigationCamera property.

NavigationCamera provides such APIs to control camera behavior:

• NavigationCamera.update(cameraState:) - transitions the camera to a different state.
• NavigationCamera.stop() - moves the NavigationCamera to NavigationCameraState.idle state at once and stops all pending transitions.

By default navigation viewport camera listens to the location updates, provided by the location publisher, passed to the initializer, during free-drive navigation and active-guidance navigation.

Default navigation viewport camera options

NavigationViewportDataSourceOptions struct provides multiple ways of changing navigation viewport camera behavior. Here are some of them:

Bearing smoothing

Bearing smoothing allows control of how much the navigation camera bearing can deviate from the course of the location, in degrees. The navigation camera bearing will be affected by the course of the current location and the direction of the upcoming framed geometry. This allows to maximize the viewable area. This option is enabled by default.

To change bearing smoothing behavior you can use BearingSmoothing struct.

For example, here's the viewable area when bearing smoothing is disabled:

Viewable area when bearing smoothing is enabled and BearingSmoothing.maximumBearingSmoothingAngle is equal to 45.0 degrees:

This code snippet can be used to change default bearing smoothing on iOS:

if let viewportDataSource = navigationViewController.navigationMapView?.navigationCamera.viewportDataSource as? MobileViewportDataSource {
    viewportDataSource.options.followingCameraOptions.bearingSmoothing.maximumBearingSmoothingAngle = 30.0
}

Geometry framing after maneuver

Geometry framing after the maneuver option extends the view by appending additional coordinates after the upcoming maneuver. This option is enabled by default.

For example, here's the viewable area when the geometry framing after the maneuver option is disabled:

Viewable area when geometry framing after the maneuver is enabled and GeometryFramingAfterManeuver.distanceToFrameAfterManeuver is equal to 1000.0 meters:

This code snippet can be used to change geometry framing after the maneuver on iOS:

if let viewportDataSource = navigationViewController.navigationMapView?.navigationCamera.viewportDataSource as? MobileViewportDataSource {
    viewportDataSource.options.followingCameraOptions.geometryFramingAfterManeuver.distanceToCoalesceCompoundManeuvers = 160.0
    viewportDataSource.options.followingCameraOptions.geometryFramingAfterManeuver.distanceToFrameAfterManeuver = 110.0
}

Pitch near maneuver

Pitch near maneuver option allows to control whether CameraOptions.pitch will update to 0.0 near upcoming maneuver. This option is enabled by default.

For example, here's viewable area when pitch near maneuver option is disabled:

Viewable area when pitch near maneuver is enabled and PitchNearManeuver.triggerDistanceToManeuver is equal to 180.0 meters:

This code snippet can be used to change pitch near maneuver on iOS:

if let viewportDataSource = navigationViewController.navigationMapView?.navigationCamera.viewportDataSource as? MobileViewportDataSource {
    viewportDataSource.options.followingCameraOptions.pitchNearManeuver.triggerDistanceToManeuver = 200.0
}

Custom navigation viewport camera options

Navigation viewport camera provides the ability to use custom CameraOptions parameters on iOS and CarPlay. To change such CameraOptions use:

• ViewportDataSource.currentNavigationCameraOptions.followingCamera
• ViewportDataSource.currentNavigationCameraOptions.overviewCamera

If you create a map view for CarPlay, specify NavigationCameraType.carPlay while creating NavigationMapView:

let navigationMapView = NavigationMapView(
    location: mapboxNavigation.navigation()
        .locationMatching.map(\.mapMatchingResult.enhancedLocation)
        .eraseToAnyPublisher(),
    routeProgress: mapboxNavigation.navigation()
        .routeProgress.map(\.?.routeProgress)
        .eraseToAnyPublisher(),
    navigationCameraType: .carPlay,
    predictiveCacheManager: mapboxNavigationProvider.predictiveCacheManager
)

To provide custom zoom level during active-guidance navigation, consider such example:

if let viewportDataSource = carPlayManager.carPlayNavigationViewController?.navigationMapView?.navigationCamera.viewportDataSource as? MobileViewportDataSource {
    viewportDataSource.options.followingCameraOptions.zoomUpdatesAllowed = false
    viewportDataSource.currentNavigationCameraOptions.followingCamera.zoom = 10.0
}

Make sure that CarPlayManager and other dependent properties are valid at the time of CameraOptions modification. If you are using free-drive navigation, do this check in the CPTemplateApplicationSceneDelegate.templateApplicationScene(_:didConnect:to:) delegate method. Otherwise, CarPlayManager and CarPlayNavigationViewController should be valid within the CarPlayManagerDelegate.carPlayManager(_:didPresent:) delegate method.

Custom navigation viewport camera

Navigation viewport camera provides the ability to fully override default camera behavior. To do this you can conform to CameraStateTransition and ViewportDataSource protocols to implement custom camera transitions and CameraOptions data source, respectively.

EXAMPLE

Custom navigation camera

Demonstrates how to add a custom data source and transition to the navigation camera.

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