Added Android Support for Make display of snapped location configurab…

android/core/src/main/java/com/stadiamaps/ferrostar/core/NavigationViewModel.kt

@@ -19,24 +19,45 @@ import uniffi.ferrostar.UserLocation
 import uniffi.ferrostar.VisualInstruction
 
 data class NavigationUiState(
+    /** The user's location as reported by the location provider. */
+    val location: UserLocation?,
+    /** The user's location snapped to the route shape. */
     val snappedLocation: UserLocation?,
+    /**
+     * The last known heading of the user.
+     *
+     * NOTE: This is distinct from the course over ground (direction of travel), which is included
+     * in the `location` and `snappedLocation` properties.
+     */
     val heading: Float?,
+    /** The geometry of the full route. */
     val routeGeometry: List<GeographicCoordinate>,
+    /** Visual instructions which should be displayed based on the user's current progress. */
     val visualInstruction: VisualInstruction?,
+    /**
+     * Instructions which should be spoken via speech synthesis based on the user's current
+     * progress.
+     */
     val spokenInstruction: SpokenInstruction?,
+    /** The user's progress through the current trip. */
     val progress: TripProgress?,
+    /** If true, the core is currently calculating a new route. */
     val isCalculatingNewRoute: Boolean?,
+    /** Describes whether the user is believed to be off the correct route. */
     val routeDeviation: RouteDeviation?,
+    /** If true, spoken instructions will not be synthesized. */
     val isMuted: Boolean?
 ) {
   companion object {
     fun fromFerrostar(
         coreState: NavigationState,
         isMuted: Boolean?,
-        userLocation: UserLocation?
+        location: UserLocation?,
+        snappedLocation: UserLocation?
     ): NavigationUiState =
         NavigationUiState(
-            snappedLocation = userLocation,
+            snappedLocation = snappedLocation,
+            location = location,
             // TODO: Heading/course over ground
             heading = null,
             routeGeometry = coreState.routeGeometry,
@@ -60,22 +81,22 @@ interface NavigationViewModel {
 class DefaultNavigationViewModel(
     private val ferrostarCore: FerrostarCore,
     private val spokenInstructionObserver: SpokenInstructionObserver? = null,
-    locationProvider: LocationProvider
+    private val locationProvider: LocationProvider
 ) : ViewModel(), NavigationViewModel {
 
-  private var lastLocation: UserLocation? = locationProvider.lastLocation
+  private var userLocation: UserLocation? = locationProvider.lastLocation
 
   override val uiState =
       ferrostarCore.state
           .map { coreState ->
-            lastLocation =
+            val location = locationProvider.lastLocation
+            userLocation =
                 when (coreState.tripState) {
                   is TripState.Navigating -> coreState.tripState.snappedUserLocation
                   is TripState.Complete,
                   TripState.Idle -> locationProvider.lastLocation
                 }
-
-            uiState(coreState, spokenInstructionObserver?.isMuted, lastLocation)
+            uiState(coreState, spokenInstructionObserver?.isMuted, location, userLocation)
             // This awkward dance is required because Kotlin doesn't have a way to map over
             // StateFlows
             // without converting to a generic Flow in the process.
@@ -85,7 +106,10 @@ class DefaultNavigationViewModel(
               started = SharingStarted.WhileSubscribed(),
               initialValue =
                   uiState(
-                      ferrostarCore.state.value, spokenInstructionObserver?.isMuted, lastLocation))
+                      ferrostarCore.state.value,
+                      spokenInstructionObserver?.isMuted,
+                      locationProvider.lastLocation,
+                      userLocation))
 
   override fun stopNavigation() {
     ferrostarCore.stopNavigation()
@@ -99,6 +123,10 @@ class DefaultNavigationViewModel(
     spokenInstructionObserver.isMuted = !spokenInstructionObserver.isMuted
   }
 
-  private fun uiState(coreState: NavigationState, isMuted: Boolean?, location: UserLocation?) =
-      NavigationUiState.fromFerrostar(coreState, isMuted, location)
+  private fun uiState(
+      coreState: NavigationState,
+      isMuted: Boolean?,
+      location: UserLocation?,
+      snappedLocation: UserLocation?
+  ) = NavigationUiState.fromFerrostar(coreState, isMuted, location, snappedLocation)
 }

android/core/src/main/java/com/stadiamaps/ferrostar/core/mock/MockNavigationState.kt

@@ -60,7 +60,11 @@ fun NavigationState.Companion.pedestrianExample(): NavigationState {
 }
 
 fun NavigationUiState.Companion.pedestrianExample(): NavigationUiState =
-    fromFerrostar(NavigationState.pedestrianExample(), false, UserLocation.pedestrianExample())
+    fromFerrostar(
+        NavigationState.pedestrianExample(),
+        false,
+        UserLocation.pedestrianExample(),
+        UserLocation.pedestrianExample())
 
 class MockNavigationViewModel(override val uiState: StateFlow<NavigationUiState>) :
     ViewModel(), NavigationViewModel {

android/demo-app/src/main/java/com/stadiamaps/ferrostar/DemoNavigationScene.kt

@@ -115,6 +115,9 @@ fun DemoNavigationScene(
         // Most vendors offer free API keys for development use.
         styleUrl = "https://demotiles.maplibre.org/style.json",
         viewModel = viewModel!!,
+        // This is the default value, which works well for motor vehicle navigation.
+        // Other travel modes though, such as walking, may not want snapping.
+        snapUserLocationToRoute = true,
         onTapExit = { viewModel!!.stopNavigation() }) { uiState ->
           // Trivial, if silly example of how to add your own overlay layers.
           // (Also incidentally highlights the lag inherent in MapLibre location tracking

android/maplibreui/src/main/java/com/stadiamaps/ferrostar/maplibreui/NavigationMapView.kt

@@ -5,7 +5,6 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.MutableState
 import androidx.compose.runtime.State
 import androidx.compose.runtime.collectAsState
-import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
 import com.mapbox.mapboxsdk.geometry.LatLng
@@ -30,6 +29,8 @@ import com.stadiamaps.ferrostar.maplibreui.runtime.navigationMapViewCamera
  * @param viewModel The navigation view model provided by Ferrostar Core.
  * @param locationRequestProperties The location request properties to use for the map's location
  *   engine.
+ * @param snapUserLocationToRoute If true, the user's displayed location will be snapped to the
+ *   route line.
  * @param onMapReadyCallback A callback that is invoked when the map is ready to be interacted with.
  *   You must set your desired MapViewCamera tracking mode here!
  * @param content Any additional composable map symbol content to render.
@@ -43,13 +44,19 @@ fun NavigationMapView(
     viewModel: NavigationViewModel,
     locationRequestProperties: LocationRequestProperties =
         LocationRequestProperties.NavigationDefault(),
+    snapUserLocationToRoute: Boolean = true,
     onMapReadyCallback: (Style) -> Unit = { camera.value = navigationCamera },
     content: @Composable @MapLibreComposable() ((State<NavigationUiState>) -> Unit)? = null
 ) {
   val uiState = viewModel.uiState.collectAsState()
 
   val locationEngine = remember { StaticLocationEngine() }
-  locationEngine.lastLocation = uiState.value.snappedLocation?.toAndroidLocation()
+  locationEngine.lastLocation =
+      if (snapUserLocationToRoute) {
+        uiState.value.snappedLocation?.toAndroidLocation()
+      } else {
+        uiState.value.location?.toAndroidLocation()
+      }
 
   MapView(
       modifier = Modifier.fillMaxSize(),

android/maplibreui/src/main/java/com/stadiamaps/ferrostar/maplibreui/views/DynamicallyOrientingNavigationView.kt

@@ -36,6 +36,8 @@ import com.stadiamaps.ferrostar.maplibreui.views.overlays.PortraitNavigationOver
  * @param viewModel The navigation view model provided by Ferrostar Core.
  * @param locationRequestProperties The location request properties to use for the map's location
  *   engine.
+ * @param snapUserLocationToRoute If true, the user's displayed location will be snapped to the
+ *   route line.
  * @param config The configuration for the navigation view.
  * @param landscapeOverlayModifier The modifier to apply to the overlay view.
  * @param portraitOverlayModifier The modifier to apply to the overlay view.
@@ -51,6 +53,7 @@ fun DynamicallyOrientingNavigationView(
     viewModel: NavigationViewModel,
     locationRequestProperties: LocationRequestProperties =
         LocationRequestProperties.NavigationDefault(),
+    snapUserLocationToRoute: Boolean = true,
     config: VisualNavigationViewConfig = VisualNavigationViewConfig.Default(),
     landscapeOverlayModifier: Modifier = Modifier.fillMaxSize().padding(16.dp),
     portraitOverlayModifier: Modifier = Modifier.fillMaxSize().padding(16.dp),
@@ -68,6 +71,7 @@ fun DynamicallyOrientingNavigationView(
         navigationCamera,
         viewModel,
         locationRequestProperties,
+        snapUserLocationToRoute,
         onMapReadyCallback = { camera.value = navigationCamera },
         content)
 

android/maplibreui/src/main/java/com/stadiamaps/ferrostar/maplibreui/views/LandscapeNavigationView.kt

@@ -38,6 +38,8 @@ import kotlinx.coroutines.flow.asStateFlow
  * @param viewModel The navigation view model provided by Ferrostar Core.
  * @param locationRequestProperties The location request properties to use for the map's location
  *   engine.
+ * @param snapUserLocationToRoute If true, the user's displayed location will be snapped to the
+ *   route line.
  * @param config The configuration for the navigation view.
  * @param overlayModifier The modifier to apply to the overlay view.
  * @param onTapExit The callback to invoke when the exit button is tapped.
@@ -52,6 +54,7 @@ fun LandscapeNavigationView(
     viewModel: NavigationViewModel,
     locationRequestProperties: LocationRequestProperties =
         LocationRequestProperties.NavigationDefault(),
+    snapUserLocationToRoute: Boolean = true,
     config: VisualNavigationViewConfig = VisualNavigationViewConfig.Default(),
     overlayModifier: Modifier = Modifier.fillMaxSize().padding(16.dp),
     onTapExit: (() -> Unit)? = null,
@@ -65,6 +68,7 @@ fun LandscapeNavigationView(
         navigationCamera,
         viewModel,
         locationRequestProperties,
+        snapUserLocationToRoute,
         onMapReadyCallback = { camera.value = navigationCamera },
         content)
 

android/maplibreui/src/main/java/com/stadiamaps/ferrostar/maplibreui/views/PortraitNavigationView.kt

@@ -39,6 +39,8 @@ import kotlinx.coroutines.flow.asStateFlow
  * @param viewModel The navigation view model provided by Ferrostar Core.
  * @param locationRequestProperties The location request properties to use for the map's location
  *   engine.
+ * @param snapUserLocationToRoute If true, the user's displayed location will be snapped to the
+ *   route line.
  * @param config The configuration for the navigation view.
  * @param overlayModifier The modifier to apply to the overlay view.
  * @param onTapExit The callback to invoke when the exit button is tapped.
@@ -53,6 +55,7 @@ fun PortraitNavigationView(
     viewModel: NavigationViewModel,
     locationRequestProperties: LocationRequestProperties =
         LocationRequestProperties.NavigationDefault(),
+    snapUserLocationToRoute: Boolean = true,
     config: VisualNavigationViewConfig = VisualNavigationViewConfig.Default(),
     overlayModifier: Modifier = Modifier.fillMaxSize().padding(16.dp),
     onTapExit: (() -> Unit)? = null,
@@ -66,6 +69,7 @@ fun PortraitNavigationView(
         navigationCamera,
         viewModel,
         locationRequestProperties,
+        snapUserLocationToRoute,
         onMapReadyCallback = { camera.value = navigationCamera },
         content)