feat: add support for maneuver images

android/src/main/kotlin/com/google/maps/flutter/navigation/Convert.kt

@@ -45,6 +45,7 @@ import com.google.android.libraries.navigation.DisplayOptions
 import com.google.android.libraries.navigation.ForceNightMode
 import com.google.android.libraries.navigation.NavigationRoadStretchRenderingData
 import com.google.android.libraries.navigation.NavigationTrafficData
+import com.google.android.libraries.navigation.NavigationUpdatesOptions
 import com.google.android.libraries.navigation.Navigator
 import com.google.android.libraries.navigation.Navigator.AudioGuidance
 import com.google.android.libraries.navigation.Navigator.TaskRemovedBehavior
@@ -857,10 +858,16 @@ object Convert {
     }
   }
 
-  fun convertNavInfo(navInfo: NavInfo): NavInfoDto {
+  fun convertNavInfo(
+    navInfo: NavInfo,
+    imageDescriptors: Map<String, ImageDescriptorDto?>,
+  ): NavInfoDto {
     return NavInfoDto(
-      currentStep = navInfo.currentStep?.let { convertNavInfoStepInfo(it) },
-      remainingSteps = navInfo.remainingSteps.map { convertNavInfoStepInfo(it) },
+      currentStep = navInfo.currentStep?.let { convertNavInfoStepInfo(it, imageDescriptors) },
+      remainingSteps =
+        navInfo.remainingSteps.mapIndexed { index, item ->
+          convertNavInfoStepInfo(item, imageDescriptors)
+        },
       routeChanged = navInfo.routeChanged,
       distanceToCurrentStepMeters = navInfo.distanceToCurrentStepMeters?.toLong(),
       distanceToNextDestinationMeters = navInfo.distanceToNextDestinationMeters?.toLong(),
@@ -882,7 +889,15 @@ object Convert {
     }
   }
 
-  private fun convertNavInfoStepInfo(stepInfo: StepInfo): StepInfoDto {
+  fun convertManeuverToKey(maneuver: Int): String {
+    return "maneuver_$maneuver"
+  }
+
+  private fun convertNavInfoStepInfo(
+    stepInfo: StepInfo,
+    imageDescriptors: Map<String, ImageDescriptorDto?>,
+  ): StepInfoDto {
+    val key = convertManeuverToKey(stepInfo.maneuver)
     return StepInfoDto(
       distanceFromPrevStepMeters = stepInfo.distanceFromPrevStepMeters?.toLong() ?: 0L,
       timeFromPrevStepSeconds = stepInfo.timeFromPrevStepSeconds?.toLong() ?: 0L,
@@ -906,6 +921,7 @@ object Convert {
           )
         },
       maneuver = convertManeuver(stepInfo.maneuver),
+      image = imageDescriptors[key],
     )
   }
 
@@ -1132,10 +1148,25 @@ object Convert {
         registeredImage.imagePixelRatio,
         registeredImage.width,
         registeredImage.height,
+        registeredImageType(registeredImage.type),
       )
     } else {
       // For default marker icon
-      ImageDescriptorDto()
+      ImageDescriptorDto(type = RegisteredImageTypeDto.REGULAR)
+    }
+  }
+
+  fun registeredImageType(type: RegisteredImageTypeDto): RegisteredImageType {
+    return when (type) {
+      RegisteredImageTypeDto.REGULAR -> RegisteredImageType.REGULAR
+      RegisteredImageTypeDto.MANEUVER_ICON -> RegisteredImageType.MANEUVER_ICON
+    }
+  }
+
+  fun registeredImageType(type: RegisteredImageType): RegisteredImageTypeDto {
+    return when (type) {
+      RegisteredImageType.REGULAR -> RegisteredImageTypeDto.REGULAR
+      RegisteredImageType.MANEUVER_ICON -> RegisteredImageTypeDto.MANEUVER_ICON
     }
   }
 
@@ -1148,4 +1179,14 @@ object Convert {
       else -> TaskRemovedBehavior.CONTINUE_SERVICE
     }
   }
+
+  fun generatedStepImagesTypeDtoToGeneratesStepImages(
+    type: GeneratedStepImagesTypeDto?
+  ): @NavigationUpdatesOptions.GeneratedStepImagesType Int {
+    return when (type) {
+      GeneratedStepImagesTypeDto.NONE -> NavigationUpdatesOptions.GeneratedStepImagesType.NONE
+      GeneratedStepImagesTypeDto.BITMAP -> NavigationUpdatesOptions.GeneratedStepImagesType.BITMAP
+      else -> NavigationUpdatesOptions.GeneratedStepImagesType.NONE
+    }
+  }
 }

android/src/main/kotlin/com/google/maps/flutter/navigation/GoogleMapsImageRegistryMessageHandler.kt

@@ -32,8 +32,12 @@ class GoogleMapsImageRegistryMessageHandler(private val imageRegistry: ImageRegi
     imageDescriptor.registeredImageId?.let { imageRegistry.unregisterImage(it) }
   }
 
-  override fun clearRegisteredImages() {
-    imageRegistry.clearRegisteredImages()
+  override fun clearRegisteredImages(filter: RegisteredImageTypeDto?) {
+    imageRegistry.clearRegisteredImages(filter)
+  }
+
+  override fun getRegisteredImageData(imageDescriptor: ImageDescriptorDto): ByteArray? {
+    return imageRegistry.getRegisteredImageData(imageDescriptor)
   }
 
   override fun getRegisteredImages(): List<ImageDescriptorDto> {

android/src/main/kotlin/com/google/maps/flutter/navigation/GoogleMapsNavigationPlugin.kt

@@ -68,7 +68,8 @@ class GoogleMapsNavigationPlugin : FlutterPlugin, ActivityAware {
     // Setup navigation session manager
     val app = binding.applicationContext as Application
     val navigationSessionEventApi = NavigationSessionEventApi(binding.binaryMessenger)
-    sessionManager = GoogleMapsNavigationSessionManager(navigationSessionEventApi, app)
+    sessionManager =
+      GoogleMapsNavigationSessionManager(navigationSessionEventApi, app, imageRegistry!!)
 
     // Setup platform view factory and its method channel handlers
     viewEventApi = ViewEventApi(binding.binaryMessenger)

android/src/main/kotlin/com/google/maps/flutter/navigation/GoogleMapsNavigationSessionManager.kt

@@ -24,11 +24,13 @@ import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.Observer
 import com.google.android.gms.maps.model.LatLng
 import com.google.android.libraries.mapsplatform.turnbyturn.model.NavInfo
+import com.google.android.libraries.mapsplatform.turnbyturn.model.StepInfo
 import com.google.android.libraries.navigation.CustomRoutesOptions
 import com.google.android.libraries.navigation.DisplayOptions
 import com.google.android.libraries.navigation.GpsAvailabilityChangeEvent
 import com.google.android.libraries.navigation.NavigationApi
 import com.google.android.libraries.navigation.NavigationApi.NavigatorListener
+import com.google.android.libraries.navigation.NavigationUpdatesOptions
 import com.google.android.libraries.navigation.Navigator
 import com.google.android.libraries.navigation.Navigator.TaskRemovedBehavior
 import com.google.android.libraries.navigation.RoadSnappedLocationProvider
@@ -54,6 +56,7 @@ class GoogleMapsNavigationSessionManager
 constructor(
   private val navigationSessionEventApi: NavigationSessionEventApi,
   private val application: Application,
+  private val imageRegistry: ImageRegistry,
 ) : DefaultLifecycleObserver {
   companion object {
     var navigationReadyListener: NavigationReadyListener? = null
@@ -704,11 +707,18 @@ constructor(
   }
 
   @Throws(FlutterError::class)
-  fun enableTurnByTurnNavigationEvents(numNextStepsToPreview: Int) {
+  fun enableTurnByTurnNavigationEvents(
+    numNextStepsToPreview: Int,
+    type: @NavigationUpdatesOptions.GeneratedStepImagesType Int,
+  ) {
     if (navInfoObserver == null) {
       // Register the service centrally (if not already registered)
       val success =
-        GoogleMapsNavigatorHolder.registerTurnByTurnService(application, numNextStepsToPreview)
+        GoogleMapsNavigatorHolder.registerTurnByTurnService(
+          application,
+          numNextStepsToPreview,
+          type,
+        )
 
       if (!success) {
         throw FlutterError(
@@ -717,9 +727,43 @@ constructor(
         )
       }
 
+      fun getManeuverIconImageDescriptor(maneuver: Int): ImageDescriptorDto? {
+        val registeredImage =
+          imageRegistry.findRegisteredImage(Convert.convertManeuverToKey(maneuver))
+        if (registeredImage == null) return null
+        return Convert.registeredImageToImageDescriptorDto(registeredImage)
+      }
+
+      fun getImageDescriptorForStepInfo(stepInfo: StepInfo): ImageDescriptorDto? {
+        val bitmap = stepInfo.maneuverBitmap ?: return null
+        val imageDescriptor = getManeuverIconImageDescriptor(stepInfo.maneuver)
+        if (imageDescriptor != null) {
+          return imageDescriptor
+        }
+        return imageRegistry.registerManeuverIcon(
+          Convert.convertManeuverToKey(stepInfo.maneuver),
+          bitmap,
+          bitmap.width.toDouble() / bitmap.height.toDouble(),
+          bitmap.width.toDouble(),
+          bitmap.height.toDouble(),
+        )
+      }
+
       // Create observer for this session manager
       navInfoObserver = Observer { navInfo ->
-        navigationSessionEventApi.onNavInfo(Convert.convertNavInfo(navInfo)) {}
+        // Map to store all the unique images for each maneuver
+        val imageDescriptors: MutableMap<String, ImageDescriptorDto?> = mutableMapOf()
+
+        (navInfo.remainingSteps + navInfo.currentStep).forEach {
+          val key = Convert.convertManeuverToKey(it.maneuver)
+          val existingImageDescriptor = imageDescriptors[key]
+          if (existingImageDescriptor == null) {
+            val imageDescriptor = getImageDescriptorForStepInfo(it)
+            imageDescriptors[key] = imageDescriptor
+          }
+        }
+
+        navigationSessionEventApi.onNavInfo(Convert.convertNavInfo(navInfo, imageDescriptors)) {}
       }
 
       // Add observer using observeForever (works without lifecycle owner)

android/src/main/kotlin/com/google/maps/flutter/navigation/GoogleMapsNavigationSessionMessageHandler.kt

@@ -254,8 +254,14 @@ class GoogleMapsNavigationSessionMessageHandler(
     sessionManager.disableRoadSnappedLocationUpdates()
   }
 
-  override fun enableTurnByTurnNavigationEvents(numNextStepsToPreview: Long?) {
-    sessionManager.enableTurnByTurnNavigationEvents(numNextStepsToPreview?.toInt() ?: Int.MAX_VALUE)
+  override fun enableTurnByTurnNavigationEvents(
+    numNextStepsToPreview: Long?,
+    type: GeneratedStepImagesTypeDto?,
+  ) {
+    sessionManager.enableTurnByTurnNavigationEvents(
+      numNextStepsToPreview?.toInt() ?: Int.MAX_VALUE,
+      Convert.generatedStepImagesTypeDtoToGeneratesStepImages(type),
+    )
   }
 
   override fun disableTurnByTurnNavigationEvents() {

android/src/main/kotlin/com/google/maps/flutter/navigation/GoogleMapsNavigatorHolder.kt

@@ -78,7 +78,11 @@ object GoogleMapsNavigatorHolder {
   }
 
   @Synchronized
-  fun registerTurnByTurnService(application: Application, numNextStepsToPreview: Int): Boolean {
+  fun registerTurnByTurnService(
+    application: Application,
+    numNextStepsToPreview: Int,
+    type: @NavigationUpdatesOptions.GeneratedStepImagesType Int,
+  ): Boolean {
     val nav = navigator ?: return false
 
     if (!turnByTurnServiceRegistered) {
@@ -90,7 +94,7 @@ object GoogleMapsNavigatorHolder {
       val options =
         NavigationUpdatesOptions.builder()
           .setNumNextStepsToPreview(numNextStepsToPreview)
-          .setGeneratedStepImagesType(GeneratedStepImagesType.NONE)
+          .setGeneratedStepImagesType(type)
           .setDisplayMetrics(displayMetrics)
           .build()
 

android/src/main/kotlin/com/google/maps/flutter/navigation/ImageRegistry.kt

@@ -20,6 +20,7 @@ import android.content.res.Resources
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import com.google.android.gms.maps.model.BitmapDescriptorFactory
+import java.io.ByteArrayOutputStream
 
 class ImageRegistry {
   val registeredImages = mutableListOf<RegisteredImage>()
@@ -32,7 +33,14 @@ class ImageRegistry {
   fun mapViewInitializationComplete() {
     isMapViewInitialized = true
     bitmapQueue.forEach {
-      addRegisteredImage(it.imageId, it.bitmap, it.imagePixelRatio, it.width, it.height)
+      addRegisteredImage(
+        it.imageId,
+        it.bitmap,
+        it.imagePixelRatio,
+        it.width,
+        it.height,
+        RegisteredImageTypeDto.REGULAR,
+      )
     }
     bitmapQueue.clear()
   }
@@ -53,9 +61,46 @@ class ImageRegistry {
       // Add to queue to make it later.
       bitmapQueue.add(QueuedBitmap(imageId, bitmap, imagePixelRatio, width, height))
     } else {
-      addRegisteredImage(imageId, bitmap, imagePixelRatio, width, height)
+      addRegisteredImage(
+        imageId,
+        bitmap,
+        imagePixelRatio,
+        width,
+        height,
+        RegisteredImageTypeDto.REGULAR,
+      )
     }
-    return ImageDescriptorDto(imageId, imagePixelRatio, width, height)
+    return ImageDescriptorDto(
+      imageId,
+      imagePixelRatio,
+      width,
+      height,
+      RegisteredImageTypeDto.REGULAR,
+    )
+  }
+
+  fun registerManeuverIcon(
+    imageId: String,
+    bitmap: Bitmap,
+    imagePixelRatio: Double,
+    width: Double?,
+    height: Double?,
+  ): ImageDescriptorDto {
+    addRegisteredImage(
+      imageId,
+      bitmap,
+      imagePixelRatio,
+      width,
+      height,
+      RegisteredImageTypeDto.MANEUVER_ICON,
+    )
+    return ImageDescriptorDto(
+      imageId,
+      imagePixelRatio,
+      width,
+      height,
+      RegisteredImageTypeDto.MANEUVER_ICON,
+    )
   }
 
   private fun addRegisteredImage(
@@ -64,9 +109,20 @@ class ImageRegistry {
     imagePixelRatio: Double,
     width: Double?,
     height: Double?,
+    type: RegisteredImageTypeDto,
   ) {
+    val imageType = Convert.registeredImageType(type)
     val bitmapDescriptor = BitmapDescriptorFactory.fromBitmap(bitmap)
-    val registeredImage = RegisteredImage(imageId, bitmapDescriptor, imagePixelRatio, width, height)
+    val registeredImage =
+      RegisteredImage(
+        imageId,
+        bitmapDescriptor,
+        imagePixelRatio,
+        width,
+        height,
+        imageType,
+        if (imageType == RegisteredImageType.MANEUVER_ICON) bitmap else null,
+      )
     registeredImages.add(registeredImage)
   }
 
@@ -117,7 +173,26 @@ class ImageRegistry {
     registeredImages.removeAll { it.imageId == imageId }
   }
 
-  fun clearRegisteredImages() {
-    registeredImages.clear()
+  fun clearRegisteredImages(filter: RegisteredImageTypeDto?) {
+    if (filter == null) {
+      registeredImages.clear()
+      return
+    }
+    registeredImages.removeAll { Convert.registeredImageType(filter) == it.type }
+  }
+
+  private fun convertBitmapToPNGByteArray(bitmap: Bitmap): ByteArray {
+    return ByteArrayOutputStream().use { stream ->
+      bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream)
+      stream.toByteArray()
+    }
+  }
+
+  fun getRegisteredImageData(imageDescriptor: ImageDescriptorDto): ByteArray? {
+    return imageDescriptor.registeredImageId?.let {
+      findRegisteredImage(imageDescriptor.registeredImageId)?.maneuverIconBitmap?.let {
+        convertBitmapToPNGByteArray(it)
+      }
+    }
   }
 }

android/src/main/kotlin/com/google/maps/flutter/navigation/RegisteredImage.kt

@@ -16,6 +16,7 @@
 
 package com.google.maps.flutter.navigation
 
+import android.graphics.Bitmap
 import com.google.android.gms.maps.model.BitmapDescriptor
 
 data class RegisteredImage(
@@ -24,4 +25,13 @@ data class RegisteredImage(
   val imagePixelRatio: Double,
   val width: Double?,
   val height: Double?,
+  val type: RegisteredImageType,
+  val maneuverIconBitmap: Bitmap?,
 )
+
+enum class RegisteredImageType(val raw: Int) {
+  /** Default type used when custom bitmaps are uploaded to registry */
+  REGULAR(0),
+  /** Maneuver icon generated from NavInfo data */
+  MANEUVER_ICON(1),
+}